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What is Pour Board? What is Copper Pour in PCB?
Monday, September 9th, 2024

What is Copper Pour in PCB Design?

Copper pour, also known as copper coating, refers to filled solid copper on PCB where without trace layout area or idle space. Instead of leaving unused areas bare, copper is poured over them, connecting it to the ground or other designated signals. The main purpose of this process is to reduce the ground impedance, improve the anti-interference ability, reduce the voltage drop. Thereby improving the power supply efficiency, and connect with the ground wire to reduce the loop area. By covering large sections of the board with copper, it also minimizes signal interference and adds a layer of protection to the PCB. Copper pour are essential for designers to maintain signal integrity and reduce unwanted noise.

What is Pour Board? What is Copper Pour in PCB?

The process of copper coating is not only very important for digital circuits, because it can effectively reduce the ground impedance, which is particularly important for digital circuits with a large number of spiking pulse currents. However, for analog circuits, the ground wire loop formed by laying copper may cause electromagnetic coupling interference.

Why Use Copper Pours on Circuit Boards?

Copper pours offer several advantages that make them an essential part of circuit board design. When creating PCBs, some engineers tend to leave many copper-free areas on the board. But a high percentage of copper-free areas on the PCB can negatively affect the product, making it vulnerable to early damage, when copper pouring comes in handy.

There are some novices who think that less copper pouring means that the cost will be lower and lower, which is wrong. It is true that the plating area is small, which can save copper, but there is no way to guarantee the quality, and the appropriate amount of copper pouring can improve the quality of the product.

When the PCB board is placed in the plating tank and the appropriate current is applied, the PCB will show the physical state after dry film coverage. After passing a current, the circuit lines exposed to the outside of the dry film will be plated with copper from the plating tank. The total area of the part of the circuit exposed outside the dry film will affect the value of the current distribution during the plating process, if the bare copper area is large, the current input is uniform, and the current received is more uniform. Therefore, a large area of copper plane must be laid in the design to prevent this from happening. If the total plating area of copper is too small or the pattern distribution is very uneven, the received current will not be uniform. In this way, when powered on, the greater the current, the thicker the copper plating layer (so designed, if only 1OZ is required, then the finished copper thickness can reach 2OZ).

What is Pour Board? What is Copper Pour in PCB?

If the gap between current traces is too small, for example about 3mil to 3.5mil, a “clip film” will form between the traces. In other words, the dry film is caught in the middle of the gap, which causes the subsequent base to start the copper in the middle, which can lead to a short circuit if the etching process is not cleaned. In order to maintain the high quality of PCB manufacturing, independent lines must be avoided as much as possible in PCB design and layout. In addition, it is recommended to use a large amount of copper on the entire PCB, if there is a separate line that cannot be covered with copper, then the continuation between the lines must be as wide as possible.

Advantages of Copper Pour Board

1. For EMC (electromagnetic compatibility) requirements, a large area of ground or power supply needs to be covered with copper, which will play a shielding role. For some special area, such as protective ground, it plays a protective role.

    What is Pour Board? What is Copper Pour in PCB?

    2. From PCB manufacturing perspective, generally in order to ensure an uniform copper plating, or avoid lamination deformation and bending, manufacturers always pour copper for those less trace layout PCB board.

    What is Pour Board? What is Copper Pour in PCB?

    3. For signal integrity PCB, pour copper gives the high-frequency digital signal a complete return path, and reduce the wiring of the DC network. In another way, pour copper can help to heat dissipation.

    What is Pour Board? What is Copper Pour in PCB?

    Disadvantages of Copper Pour

    1. If the pins of the components are fully covered with copper, the heat dissipation may be too fast, resulting in difficulties in dismantling and repairing the components. Therefore, sometimes in order to avoid this situation, cross connections are used for components (pin contact and pad contact are shown in “+”).

      What is Pour Board? What is Copper Pour in PCB?

      2. Pouring copper in the area around the antenna is easy to cause weak signal, interfered acquisition signal, and the impedance of copper will affect the performance of the amplifier circuit. So the area around the antenna section is usually not covered with copper.

      What is Pour Board? What is Copper Pour in PCB?

      Copper Pour vs Ground Plane

      There’s often confusion between copper pours and ground planes. While both serve similar purposes, they are not the same. A ground plane is a layer dedicated entirely to the ground signal, covering the entire surface of a board layer. It ensures a low-impedance path for electrical signals, minimizing interference.

      Copper pours, on the other hand, are not necessarily tied to the ground. Designers can connect copper pours to any net, including power lines or signal traces. The primary goal of a copper pour is to fill in empty spaces, whereas a ground plane is dedicated exclusively to providing a ground connection.

      Implementation of PCB Copper Pours

      When designing a PCB with copper pours, a few best practices help in optimizing its performance. Here are some useful tips:

      • Assign Copper Pours to Ground First

      When designing, prioritize assigning continuous copper to ground layers over power planes. A solid ground plane improves overall performance, providing a reliable reference for signals and reducing noise. Every PCB should have strong, consistent ground connections.

      • Monitor Trace Currents

      Although reducing inductance is advantageous, flooding the board with copper can sometimes interfere with circuit tuning. Be mindful of traced paths, especially in high-current areas, to maintain proper load control.

      • Maintain Symmetry in Copper Pours

      Ensure copper pours are symmetrical on both sides of the PCB. This balance helps prevent issues like board warping due to uneven expansion or moisture absorption. Symmetrical copper distribution is essential for the board’s structural integrity.

      • Avoid Acute Angles

      Keep copper pours free from long, narrow protrusions or angles sharper than 45 degrees. Such shapes can become weak points, breaking off or acting as antennas during vibration or shock, potentially causing functional failures.

      • Incorporate Relief Features

      Adding slots, anti-pads, and thermal spokes can relieve stress caused by material expansion, especially for large copper pours used on power planes. These features ensure mechanical stability and ease soldering.

      • Carefully Review Design Masks

      Automated copper pour shapes may need manual adjustments to remove artifacts or undesirable patterns around complex components. Always review and fine-tune these masks to achieve optimal results.

      When copper pours are correctly connected to appropriate nets, designers can enhance both the electrical and physical properties of the circuit by distributing copper strategically across the board.

      Copper Pour Clearances and Settings

      When designing a PCB with copper pours, clearances and settings play a crucial role in ensuring proper functionality and avoiding issues like short circuits. Here are PCB copper pour suggestions based on standard PCB board: 

      1. Trace to Copper Pour Clearance

      • Standard clearance: 0.2 mm (200 µm) or 8 mils
      • High-voltage applications: 1 mm (1000 µm) or 40 mils (or more, depending on voltage levels)

      2. Pad to Copper Pour Clearance

      • SMD pads: 0.2 mm to 0.3 mm (8-12 mils)
      • Through-hole pads: 0.3 mm to 0.5 mm (12-20 mils)

      You can adjust these values based on the pad size and the net to which the copper pour is connected.

      3. Copper Pour Width and Thickness

      The width and thickness of the copper pour should be chosen based on the current-carrying capacity of the board:

      • Minimum width: 1.5 mm (60 mils) for low-current signals
      • Power lines: At least 2-3 mm (80-120 mils), depending on current
      • Copper thickness: 35 µm (1 oz/ft²) is standard, but for higher currents, you can use thicker copper like 70 µm (2 oz/ft²) or more.

      4. Via Clearance in Copper Pours

      • Standard via clearance: 0.2 mm (8 mils)
      • High-current via clearance: 0.5 mm (20 mils)

      Clearance should be adapted to the board’s layer stack-up and current needs.

      5. Thermal Relief Spokes

      • Spoke width: 0.3 mm to 0.5 mm (12-20 mils)
      • Spoke count: Typically 4 thermal relief spokes per pad
      • Clearance to pad center: 0.5 mm (20 mils)

      6. Copper Pour to Board Edge Clearance

      • Standard clearance: 0.5 mm (20 mils) from the board edge
      • High-voltage boards: 1 mm (40 mils) or more

      Layer Placement of Copper Pours

      Copper pours can be placed on any layer of a PCB. In multi-layer PCBs, copper pours are often added on internal layers to maximize performance. For example, ground and power pours are frequently found on internal layers to reduce noise and improve thermal dissipation.

      On outer layers, copper pours serve to enhance thermal management. They distribute heat from high-power components and help maintain an even temperature across the board. It’s important to balance the placement of copper pours with other components to ensure overall board stability and functionality.

      What is Pour Board? What is Copper Pour in PCB?

      Copper Pour PCB Design Considerations

      1. The open areas in the design must be minimized and the open Spaces filled with copper.

      2. It’s important to assess the current-carrying capacity. Make sure the copper pour is thick enough to handle the expected current loads, especially in power applications.

      3. If there is no room for the copper, the two wires, the two pads, and the distance between the wires and the pads are designed to be 2 ounces thick with a minimum spacing of 8 mil.

      4. When pouring copper, keep a certain distance from the ordinary touch pad. The distance between the track, the common plane and the drilled area should be greater than 0.5 mm. The copper must be poured as firmly as possible. Avoid pouring copper on small grids.

      5. The inner layer of the gold finger must be all poured copper to avoid thinning of the board at the gold finger. Avoid choosing laminated structures with thin plates.

      6. Those thin long, poorly grounded ground copper will have an antenna effect, which will cause poor EMC problems. Therefore, we should try to avoid causing broken copper when coating copper, such as causing broken copper can be removed.

      7. Isolated (dead zone) copper problem, isolated copper if relatively small equivalent to broken copper can be deleted. If it is large, it can be defined as a place to add through the hole treatment, at this time there is no isolated copper.

      8. Refer to the product design manual and apply copper coating near the antenna. Any interference or interference with the antenna must be avoided when pouring fake copper.

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      How to Calculate Current Carrying Capacity in PCB Vias?
      Thursday, September 5th, 2024

      What are vias in PCB design?

      Via hole is one of the important components of multi-layer PCB, and the cost of drilling usually accounts for 30% to 40% of the PCB board cost. Simply put, every hole on the PCB can be called a pass hole. From the function point of view, the hole can be divided into two categories: one is used as an electrical connection between the layers. The second is used as the fixing or positioning of the device.

      How to Calculate Current Carrying Capacity in PCB Vias?

      From a manufacturing process perspective, vias can be divided into three types: blind vias, buried vias, and through vias:

      • Blind vias: These connect the surface layer to an internal layer, without going through the entire board. Their depth is typically related to the hole diameter.
      • Buried vias: Located inside the PCB, they don’t reach the surface.
      • Through vias: These pass through the entire board and are the most common due to their lower manufacturing cost and simpler process.

      How to make PCB vias?

      Typically, PCB vias are produced following the IPC-2 standard, where the copper thickness in the hole is around 0.8 mil to 1 mil. However, in practice, the copper plating might not be uniform, and the thinnest part could be as narrow as 0.7 mil, affecting the current-carrying capacity.

      Generally, the conventional PCB board is produced according to IPC-2 standard, where the copper thickness in the hole is around 0.8 mil to 1 mil (you can check the specific content of the IPC-2 standard). The hole that we think is produced during production is this ideal situation (as shown below), the size of the hole is regular, and the thickness of the hole copper is very symmetrical:

      How to Calculate Current Carrying Capacity in PCB Vias?

      However, in practice, the copper plating might not be uniform. As you can see, the copper plating thickness of the perforated wall of the PCB produced in general may be wide up and down, and narrow in the middle, so the narrowest limit may be 0.7mil. It can be imagined that if the current carrying situation is evaluated, it should be calculated according to the smallest and smallest cross-sectional area, but the smallest cross-sectional area is deviated from the actual design value. But actually, a good PCB manufacturer can help to save much time and money for you, you can see the via holes cross-sectional made by Best Technology and others.

      How to Calculate Current Carrying Capacity in PCB Vias?

      What Is the Current Carrying Capacity of a Via?

      The current-carrying capacity of a via refers to the maximum current it can safely handle. In PCB design, vias are essential components that connect traces between layers, and their size and shape directly impact how much current they can carry. Factors affecting current capacity include via diameter, number of vias, and placement.

      The current carrying capacity of a via hole refers to the current that can be safely carried by the hole. In PCB design, the hole is a key component connecting the layers of printed wires. Their size and shape directly affect the ability of current to pass through. The current carrying capacity of the hole is not only related to the diameter of the hole, but also affected by the uneven current distribution. That is, when multiple holes are actually placed, the current distribution is not equal, which is related to the distribution, quantity and location of the hole. Therefore, evaluating the current carrying capacity of the holes requires consideration of a variety of factors, including the size and number of holes, and their layout on the board.

      For instance, a 12 mil via can safely carry around 1.2A of current. However, increasing the via size (e.g., to 16 mil, 20 mil, or 24 mil) doesn’t necessarily yield a proportional increase in current capacity. A recommended via size for optimal current handling is 10-12 mil.

      In some cases, the current carrying capacity of the through hole can be evaluated by DC simulation software, such as using tools such as Allegro’s IR Drop. These tools can help designers more accurately predict and optimize the performance of the board.

      How to Calculate Current Carrying Capacity in PCB Via?

      The current-carrying capacity of a via can be simplified by using a trace model calculation. The formula is:

      I = 0.048 * T^0.44 * A^0.75

      Where:

      I is the maximum allowable current in amperes (A).

      T is the maximum temperature rise in degrees Celsius.

      A is the cross-sectional area of the via, measured in square mils.

      For the cross-sectional area of the via: A = π * (D + Tk) * Tk

      Where:

      D is the via’s diameter.

      Tk is the copper thickness, typically around 20 μm (0.8 mil) according to IPC-2 or IPC-3 standards.

      In high-density interconnect (HDI) boards, due to manufacturing constraints, the copper thickness may be reduced to as low as 10 μm.

      PCB Via Current Calculator Per IPC 2152

      IPC-2152 replaces the 50-year-old IPC-2221B standard. IPC-2221B identifies in a series of diagrams the connection between the PCB’s temperature rise, the current in the track, and the cross-sectional area of the track without multilayer boards.

      IPC-2152 outlines the relationship of thermal conductivity, through hole, board material, and thickness to current, trace cross section, copper weight, and temperature. It can also determine the exact values of external and internal traces. IPC-2152 is not only a real-time protection program, but it also helps PCB designers model safe and appropriate designs. The Best Technology Wire Width and current Capacity calculator is based on this standard. You can calculate the trace area and current capacity for a given temperature rise.

      The figure below is the calculation chart of the cross-sectional area of the through-hole given by IPC 2152. The formula of the cross-sectional area of the through-hole wall in the above figure is transformed, where D is the empty outer diameter, D is the inner diameter of the hole, and (d-d)/2 is the thickness of the hole wall, also known as the through-hole copper thickness. Where D is the empty outer diameter, D is the inner diameter of the hole, and (d-d)/2 is the thickness of the hole wall, also known as the thickness of copper through the hole. The copper thickness through the hole is not determined, and the copper thickness of each PCB manufacturer may be different. If you want to pass a larger current through the hole, it may be better to punch several more through the hole.

      How to Calculate Current Carrying Capacity in PCB Vias?

      Then you can get a new formula of calculating cross sectional area of hole wall:

      How to Calculate Current Carrying Capacity in PCB Vias?

      A typical example is calculating the via size based on a 20°C temperature rise and a 1A current.

      Given:

      Copper thickness of 1 oz (1.38 mil)

      Current carrying capacity of 1A

      Maximum temperature rise of 20°C

      From the IPC-2152 Conservative Chart, the cross-sectional area corresponding to these conditions is 28 mil². Using the equation for the via’s cross-sectional area, you can calculate the via’s diameter.

      From the chart, the required cross-sectional area is 28 mil².

      The copper thickness is 1.38 mil.

      Solving for the via diameter, we get:

      d = 7.28 mil (0.185 mm)

      Thus, a via with an internal diameter of 0.185 mm will safely carry a 1A current with a 20°C temperature rise.

      Best Technology’s Via Current Capacity Calculator

      Best Technology offers a current capacity calculator for PCB vias to ensure that designs meet specific current-carrying needs. The tool allows designers to input their parameters, such as via diameter and copper thickness, and outputs the current-carrying capacity value. Clik below image to use or click here: via current capacity calculator

      How to Calculate Current Carrying Capacity in PCB Vias?

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      What are the types of PCB boards?
      Monday, August 26th, 2024

      PCB (Printed Circuit Board) boards can be classified according to their constituent materials and characteristics. PCBs are classified into single-sided boards, double-sided boards, and multi-layer boards according to board applications. They are classified into flexible PCB boards (flexible boards), rigid PCB boards, rigid-flexible PCB boards (rigid-flexible boards) according to materials, etc.

      PCB is an important electronic component, a support for electronic components, and a provider of electrical connections for electronic components. Since it is made using electronic printing technology, it is also called a printed circuit board. PCB is simply a thin board with integrated circuits and other electronic components.

      1. Single-sided board:

      On the most basic printed circuit board, parts are concentrated on one side and wires are concentrated on the other side. Because wires only appear on one side, this type of printed circuit board is called a single-sided board. Because single-sided boards have many strict restrictions on designing circuits (because there is only one side, wiring cannot cross and must go around a separate path), early circuits used this type of circuit board.

      2. Double-sided board

      What are the types of PCB boards?

      This type of circuit board has wiring on both sides. In order to connect the wires on both sides, there must be a proper circuit connection between the two sides. This connection between the circuits is called a guide hole. A guide hole is a small hole filled or coated with metal on a printed circuit board, which can be connected to the wires on both sides. Because the area of a double-sided board is doubled that of a single-sided board, and the wiring can be interlaced (can go around to the other side), double-sided boards can be used on more complex circuits than single-sided boards.

      3. Multilayer board:

      In order to increase the area that can be wired, multilayer boards use more single- or double-sided wiring boards. Multilayer boards use several double-sided boards, and put an insulating layer between each layer of boards and glue them firmly. The number of layers of the circuit board represents how many independent wiring layers there are, usually an even number of layers, and includes the two outermost layers.

      4. Flexible PCB board

      Flexible PCB board is a printed circuit board made of a flexible substrate. Its advantage is that it can be bent, which is convenient for the assembly of electrical components. Flexible circuit board, flexible PCB, flexible circuit and multi-function printed circuit are other names for these circuit boards. These printed circuit boards are made using the same components as rigid printed circuit boards. The main difference is that the circuit board is designed to bend to the desired shape throughout the application process. These PCBs are available in single-sided, double-sided, and multi-layer configurations. This helps reduce the complexity of unit assembly.

      5. Rigid PCB Board

      Rigid PCB is a circuit board that cannot be twisted or folded. The base material of the board is a rigid substrate, which gives the board rigidity and strength. They are composed of multiple layers, including substrate layers, copper layers, solder mask layers, and silk screen layers, which are bonded together by adhesives and heat. While some circuit boards are single-sided, double-sided, or multi-layered, rigid PCBs can be any of these as needed. However, once made, they cannot be modified or changed.

      6. Rigid-Flex Board

      Rigid-Flex Board is a hybrid circuit board that combines elements of flexible and rigid circuit boards to form a foldable or continuously bendable circuit board, which is usually molded into a curved shape or curve during the manufacturing process.

      What are the types of PCB boards?

      The flexible portion of the circuit board is often used for interconnections between rigid circuit boards, allowing narrower wires to take up less space, thereby reducing the size of the circuit board. Using flexible PCBs for interconnections often eliminates the need for bulky and heavy connectors, making rigid-flex boards lighter. The design of rigid-flex boards is slightly more complicated because these boards are 3D constructed, allowing the board to be folded or twisted to produce the shape required for the product.

      7. High-frequency PCB board

      High-frequency circuits refer to the overall circuit board design, not the other types of circuit board structures we described earlier. These PCBs are designed to conduct signals over 1 GHz.

      High-frequency boards mostly use FR4-grade glass-reinforced epoxy boards, polyphenylene ether (PPO) resins, and Teflon, but Teflon has a low and stable Dk value, low dielectric loss, low hygroscopicity, and is slightly more expensive.

      When designing high-frequency circuits, various factors must be considered, such as Dk value, dissipative loss, and dielectric thickness. The DK value of the substrate is an important factor to remember. Substrates with a higher probability of Dk value changes usually experience impedance changes, which affects the harmonics that make up the electrical signal, resulting in poor signal integrity.

      8. Copper substrate

      Copper substrate is a metal substrate with high thermal conductivity, suitable for high-frequency circuits and areas with large high and low temperature changes and heat dissipation and architectural decoration industries for precision communication equipment.

      The copper substrate circuit layer requires a large current carrying capacity, and a thicker copper foil should be used, with a thickness of generally 35μm~280μm. The thermal conductive insulation layer is the core technology of the copper substrate. It is composed of core thermal conductive components and high molecular polymers, with low thermal resistance (0.15), excellent viscoelastic properties, resistance to thermal aging, and the ability to withstand mechanical and thermal stress.

      The copper substrate metal base is the supporting member of the copper substrate, which is required to have high thermal conductivity. It is generally a copper plate, and a copper plate can also be used (where the copper plate can provide better thermal conductivity). It is suitable for conventional mechanical processing such as drilling, punching and cutting.

      9. Aluminum-based PCB board

      The design of aluminum-based PCB circuits is similar to that of copper-based PCBs, but the substrate material of aluminum-based PCBs is aluminum metal, rather than the standard glass fiber used in most circuits.

      What are the types of PCB boards?

      The aluminum layer is reinforced with the least heat-resistant insulation material, which means less heat is transferred from the insulation material to the backing. After applying the insulation layer, another layer of copper is required.

      10. High Density Interconnect (HDI) PCB

      Among the many types of PCBs, HDI PCB is a circuit with multiple interconnections that takes up very little space. HDI components are mounted close to each other, minimizing PCB space while maintaining high functionality. Boards containing 120-160 pins per square inch are classified as HDI PCBs.

      HDI designs integrate dense device mounting and multi-purpose wiring. With the help of microvias, buried vias, and blind vias, compact circuits can be made, minimizing drilling to copper. For the electrical requirements of high-speed signals, HDI PCBs must have high-frequency conduction capabilities, impedance control, and minimal redundant radiation.

      11. Thick Copper PCB

      Thick copper PCB is also called heavy copper PCB. Basically, it contains more than 2 ounces of copper in the inner and outer layers of the board. Heavy copper transmitters significantly increase the overall thickness of the board; thick copper boards are known for supporting high currents, high temperatures, and cyclical thermal cycles.

      12. High TG PCB

      Among various types of PCBs, high Tg PCBs are circuit boards designed to work at high temperatures. Glass transition temperature (Tg) is an essential element of any epoxy resin. It is basically the temperature point at which the polymer changes from a hard glass substrate to a soft rubber substrate. The substrates used to make high Tg circuit boards must be flame retardant, which means that they soften instead of burning at the glass transition point (Tg).

      The higher the Tg value, the higher the temperature requirement during lamination. Under such conditions, the PCB will become hard and brittle, affecting the aperture size and related electrical properties. Standard boards will soften, deform and melt under such conditions, and their mechanical and electrical properties will be significantly reduced.

      Standard FR-4 Tg is between 130-1400C, medium Tg is between 150-1600C, and high Tg is above 1700C. The higher the Tg value, the better the board’s heat, moisture and chemical resistance.

      Conclusion:

      PCB board types are updated and iterated with the rapid development of the industry, and various types of PCB boards have gradually evolved to cope with various application scenarios, adding corresponding materials according to the required performance. BEST Technology has various PCB types of manufacturing technology, which can meet your any type of PCB needs.

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      What are the factors that affect the price of PCB boards?
      Tuesday, August 20th, 2024

      There are many factors that affect pcb board price. The diversity of PCB processing prices has its inherent inevitable factors, which are closely related to materials, processes and other aspects. As an important part of electronic components, PCB boards play a very important role in the electronics industry. One of the important problems is that prices fluctuate greatly, which brings great uncertainty to the production and operation of enterprises.

      How much do pcb board price?

      The price of PCB is determined by many factors, including board cost, processing cost, quality inspection cost, etc. ‌

      ‌Board cost‌ is the main component of PCB cost, accounting for about half of the total cost. The cost of boards depends on factors such as material, thickness, size and quality. For example, the prices of different types of plates such as FR4, CEM-1, and aluminum substrates vary significantly. The cost of panels will be affected by multiple factors such as market supply and demand, raw material price fluctuations, and the complexity of the production process.

      What are the factors that affect pcb board price?

      ‌Processing costs‌ include cutting, drilling, electroplating, lamination and other links. The equipment and process requirements of each link will affect the final cost. The depreciation costs of high-end equipment, workers’ operational proficiency and the degree of optimization of the production process are all key factors that affect processing costs.

      ‌Quality inspection cost‌ is also an important part of PCB cost. Strict quality testing is required during the production process, including environmental adaptability testing, electrical performance testing, etc. The number and stringency of these testing items will also affect production costs.

      In addition, the cost of PCB also includes indirect costs, such as equipment depreciation expenses, labor costs, management expenses, R&D expenses, etc. Batch size and yield control are also important factors that affect cost. Large-volume production usually reduces unit costs, and high yield means lower costs. Therefore, the specific cost of PCB needs to be comprehensively evaluated based on factors such as specific board type, processing requirements, testing standards, and production batches.

      Why is PCB so expensive?

      ‌The price of PCB is high mainly because its production involves multiple cost factors and complex processes. ‌

      The production cost of PCB is affected by the cost of materials.

      PCB boards are mainly made of materials such as copper, fiberglass, and epoxy resin. The cost of these materials directly affects the final price of the PCB board. In addition, the complexity of PCB design and manufacturing is also an important factor affecting the price. The design and manufacturing process requires precise tools and specialized skills. The more complex the design, the higher the fees paid to the designer. The complexity of the manufacturing process will also lead to increased costs.

      Accuracy and quality are also key factors in determining pcb board price.

      High-precision PCBs require higher manufacturing costs because they require more precise tools and more rigorous manufacturing processes. High-quality PCBs usually need to go through more quality control steps, which also increases costs.

      Supply chain and regional differences are also factors that affect pcb board price.

      Changes in the global supply chain and differences in production costs in different regions will be reflected in pcb board price.

      In terms of production process.

      PCB production includes multiple stages, such as pre-processing, image transfer, electroplating, etching, inspection and trimming, and post-processing. Each stage requires specific technology and equipment, which also increases production costs.

      In addition, the price of PCB is also affected by a variety of other factors, including surface treatment technology, copper foil thickness, customer’s quality acceptance standards, mold fees and test rack fees, payment methods and order volume/delivery time, etc. For example, different surface treatment processes (such as OSP, leaded tin spraying, lead-free tin spraying, etc.) and copper foil thickness will lead to price differences; the higher the customer’s quality acceptance standards, the higher the price; mass production may require Molds and test racks, which also add cost.

      To sum up, the high price of PCB is mainly due to the fact that its production involves a variety of materials, complex processes, high precision and quality requirements, and a variety of factors that affect cost.

      How much gold is in a PCB board?

      ‌PCB boards contain a certain amount of gold, but the exact amount varies depending on the type and application of the PCB board.

      What are the factors that affect pcb board price?

      PCB board (printed circuit board) is an indispensable component of most electronic products and is used to interconnect circuits. With the development of technology, some special electronic copper-clad laminates can even be used directly to manufacture electronic components.

      In the manufacturing process of PCB boards, gold is often used as a material for surface treatment, especially in some high-end or special application PCB boards. For example, components such as motherboards, CPUs, random access memory chips (RAM), internal modems, PCI boards, Ethernet ports, etc. often contain gold on their connection pins and surface layers. The use of this gold not only increases the value of the product, but also improves its performance and reliability‌.

      As for the specific gold content, although there is no fixed ratio, data shows that 1 ton of circuit boards contains at least 80 grams of gold, and chip packaging also contains gold and other precious metals such as silver. This shows that recycling precious metals such as gold from electronic waste has considerable economic value‌. In addition, the application of gold in PCB boards is usually achieved by electroplating. Sometimes a layer of nickel is added between gold and copper as a barrier layer to prevent electron migration and diffusion reactions between them.

      To sum up, although the gold content in PCB boards is not high, its existence is crucial to improving the performance and reliability of electronic products, and it also has certain economic value in electronic waste recycling.

      How much does it cost to replace a PCB board?

      Cost estimation method in PCB processing factory The cost of PCB is composed of many factors. Most of the cost comes from the number of layers, material, drilling volume, surface treatment process, etc. of the board. Generally speaking, the cost of the board is about 1% of the total cost. About half.

      According to speculation, the processing cost of PCB with more than 6 layers of material per square centimeter can be estimated as follows:

      (1) For every two additional layers of the line, the cost increases by 0. 05 yuan, that is, 0. 05 yuan/cm2;

      (2) Screen printing layer and solder mask layer, film cost, 300 yuan;

      (3) The circuit layer film fee is 100 yuan per layer.

      Actual costs should be inquired from the manufacturer.

      Design requirements (1) Among the PCB processing costs, the board cost accounts for about half. Therefore, the smaller and thinner the board size, the higher the utilization rate, and the lower the cost.

      (2) In terms of surface treatment, based on spray tin spraying, the surface treatment cost OSP is about 20% lower, ENIG is about 20% higher, and Im-Sn and Im-Ag are basically the same as spray tin spraying.

      (3) The number of laminations has a greater impact on the cost. Each additional time will increase the total cost by about 3%.

      (4) Special processes, such as buried copper, are relatively expensive and require separate communication with the manufacturer.

      (5) The cost of line width/line spacing less than or equal to 3mil/3mil is about 6% higher than the cost of greater than 3mil/3mil.

      (6) Adding one stage to the HDI board will increase the cost by about 18%. Therefore, the use of HDI needs to be carefully considered.

      Are old PCBs worth anything?

      Old PCBs not only have economic value, but also have important significance and value in environmental protection, art, etc.

      pcb board price?

      There are a lot of gold elements on old PCBs, because circuit interfaces are often plated with gold to increase contact performance and prevent corrosion. In addition, waste printed circuit boards also contain a variety of valuable metals. The main direction of recycling waste circuit boards is the recycling of metals.

      These circuit boards contain a large amount of precious metals and rare materials. According to data, the metal contains about 20% copper, 8% iron, 2% nickel, 4% tin, 2% zinc and other common metals, and about 0.1 % gold, 0.2% silver, 0.005% palladium and other precious metals, and also contains many toxic and harmful heavy metals, such as lead, hexavalent chromium, mercury, cadmium, etc. With the right recycling techniques and processes, these valuable materials can be extracted and used to produce new electronic products.

      This can not only save resources and reduce damage to the natural environment, but also effectively reduce production costs. Therefore, discarded PCB circuit boards should not be simply regarded as garbage, but should be regarded as a valuable resource.

      With a combination of technology and creativity, electronics enthusiasts and artists have discovered a variety of ways to transform discarded circuit boards into unique pieces of art, home décor, or functional items. Through careful disassembly and reassembly, these discarded circuit boards are given a new life.

      How can I make PCB cheaper?

      1. ‌Optimized design‌: Correct component placement and layout design can significantly reduce PCB costs and improve circuit performance‌.

      2. ‌Choose the right material‌: Choose the right PCB material according to the application scenario.

      3. Optimize line spacing: By optimizing line width and line spacing, you can avoid additional adding.

      4. Optimize the process‌: Use more efficient manufacturing processes such as the V-cut process to reduce material waste and improve sheet utilization.

      5. ‌Mass production and panelization‌: Carry out mass production according to demand, enjoy batch discounts and discounts, and reduce unit prices‌.

      6. ‌Technical improvement‌: Introduce advanced equipment and processes to improve production efficiency and reduce error rates, thereby reducing production costs‌.

      Through the comprehensive application of the above strategies, the cost of PCB can be effectively reduced while ensuring product quality and production efficiency.

      Conclusion:

      Understanding the factors that affect pcb board price during the production and processing stages can help you make cost-effective decisions to ensure the quality of your products while saving money. BEST Technology has extensive design and production experience in PCB manufacturing and can effectively help you solve pcb board price issues.

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      What is a heavy copper PCB?
      Monday, August 19th, 2024

      With the development of society, the demand for heavy copper PCBs in different industries has become increasingly greater. At present, heavy copper PCBs have been widely used in various electronic industries. Generally speaking, heavy copper technology can realize complex switches in a limited space, combine circuits with high current levels, and is conducive to heat dissipation. Multilayer and double-sided are the most common designs we know. More importantly, heavy copper PCB technology makes it possible to combine good layout structures on the outer layer and Heavy copper layers on the inner layer.

      What is a heavy copper PCB?

      Heavy copper PCB is a special printed circuit board (PCB) characterized by a very high concentration of copper, usually up to 200 ounces per square foot, and the copper content of the inner and outer layers of the circuit board is above 3 ounces (oz), which enables heavy copper PCBs to conduct extremely high currents, achieve good heat distribution, and realize complex circuit layouts in a limited space.

      What is a heavy copper PCB?

      In the design and manufacturing process of heavy copper PCBs, thermal stress handling is an important consideration. Engineers need to eliminate thermal stress as much as possible to maintain the circuit while minimizing the power budget, while taking into account environmentally friendly design.

      With the development of PCB manufacturing process, modern manufacturing technology such as the use of aluminum PCB can better handle thermal stress problems.

      The heat dissipation capacity of Heavy copper PCB is better than the traditional solution of using external heat sink, because it prints the heat sink directly on the circuit board during the manufacturing process, and achieves rapid heat transfer through conductive through-holes, thereby improving heat dissipation performance.

      In general, Heavy copper PCB is a high-performance electronic component carrier, which provides an ideal solution for applications requiring high power and high reliability through its high copper content and optimized thermal management characteristics.

      What is the difference between PCB and Heavy copper PCB?

      Copper board and Heavy copper board look similar in name, and people tend to think that they are the same PCB, but in fact they refer to different things.

      1. PCB:

      PCB refers to a copper-based PCB. The use of copper as a substrate is to better dissipate heat and extend the life of components on the PCB. The copper substrate is to allow heat to be quickly transferred from the PCB to the outside, such as a heat sink or a metal casing. Because the thermal conductivity of copper is several times that of aluminum or other metals, up to 401W/MK.

      What is a heavy copper PCB?

      2. Heavy copper PCB:

      Heavy copper PCB refers to PCB with copper thickness exceeding 3OZ. The substrate can be aluminum or FR4. Heavy copper is to enable PCB to carry large current. Please note that Heavy copper here does not refer to the thickness of PCB, but the thickness of copper foil on PCB. Both aluminum PCB and FR4 PCB can thicken the copper foil.

      What is the maximum copper thickness on Heavy copper PCB?

      ‌The maximum thickness of copper on Heavy copper PCB can reach 20oz. ‌

      In circuit board design and manufacturing, copper thickness is an important parameter, which directly affects the electrical performance, heat dissipation capacity and mechanical strength of the circuit board. For applications that need to carry large currents, it is necessary to choose a thicker copper layer.

      The copper layer thickness of Heavy copper ultra-thick PCB is generally between 2oz and 20oz. This range of copper layer thickness can ensure the stability and reliability of the circuit board while providing good heat dissipation performance.

       In practical applications, according to international standards, the copper thickness of PCB boards can be divided into standard copper thickness and non-standard copper thickness. Standard copper thickness includes 1oz (35um) and 2oz (70um), while non-standard copper thickness covers 0.5oz (17um), 3oz (105um) and 4oz (140um). For some special applications, such as high-power LED lights, electronic high-frequency circuits, etc., a higher copper thickness may be required. At this time, non-standard copper thickness will be selected, up to 20oz.

      During the manufacturing process, a Heavy copper foil is first adhered to the substrate, and then the circuit pattern is transferred to the copper foil through a photolithography process. Then chemical etching is performed to remove excess copper, and finally the thickness of the copper layer is further increased through an electroplating process to ensure that the Heavy copper PCB can meet the requirements of high current and high power applications.

      Finally, surface treatment is performed to protect the copper circuit from oxidation and corrosion. Common surface treatment methods include hot air leveling (HASL), lead-free tin spraying, nickel gold (ENIG), etc. During the entire manufacturing process, process parameters must also be strictly monitored to ensure the uniformity and thickness consistency of the copper layer.

      What are the advantages of Heavy copper PCBs?

      1. Heavy copper PCBs have better current conductivity and can withstand excessive current loads. Because thicker copper wires have higher current carrying capacity, their current carrying capacity can be increased by increasing the copper wire width.

      2. Heavy copper inner layers are ideal power distribution layers in multi-layer PCBs, which minimize ground bounce and power supply noise

      3. Improve thermal performance and increase heat dissipation. Can withstand repeated thermal cycles during manufacturing and assembly.

      4. Provide high mechanical strength in connector locations and plated through holes.

      5. Due to the presence of copper layers, the size of the circuit board is reduced.

      What are the disadvantages of Heavy copper PCBs?

      1. Heavy copper PCBs are more expensive to manufacture than standard PCBs because more specialized equipment and richer expertise are required.

      2. Heavy copper PCBs are more difficult to process because the PCBs may be heavier and bulkier than other PCBs.

      What are the properties of Heavy copper PCBs?

      High mechanical strength: After Heavy copper is applied to the circuits and vias of the board, the printed circuit board has super high mechanical strength, and the weather resistance of the circuit board and electrical system is more stable and has a high melting point. Hot melt welding methods such as oxygen blowing can be used, and it is not easy to become brittle at low temperatures. Even in an extremely corrosive atmospheric environment, Heavy copper PCBs can form a strong, non-toxic passivation protective layer.

      Excellent weather resistance: Because Heavy copper PCB boards support the selection of a variety of dielectric materials. It improves the overall weather resistance of the board and can ensure the stability of circuit transmission signals under certain high temperature or extreme special environments.

      Thermal management: With the advancement of modern technology, PCBs are becoming more and more complex, and high-density currents increase the difficulty of thermal management. Excessive temperature will affect the normal operation of electronic equipment and even cause damage. Heavy copper PCB boards can provide stronger heat dissipation capabilities. With heat sinks and copper plating on through holes, the heat generation of the board can be greatly reduced.

      Excellent current conductivity: In the operation of electronic equipment, Heavy copper printed circuit boards are excellent current conductors that can connect and transmit power between various boards.

      Diversity: Plating of Heavy copper circuits allows Heavy copper PCB manufacturers to increase the copper weight of via sidewalls and plated holes, thereby reducing the number of layers and occupied space.

      Ductility: Heavy copper PCBs have the best ductility and are not limited by processing temperature.

      High performance: Heavy copper plating integrates high current and control circuits, allowing high density with a simple board structure.

      Where are Heavy copper PCBs used?

      1. Automotive electronics

      What is a heavy copper PCB?

      2. Grid switching systems

      3. Power line monitors

      4. Security and signal systems

      5. Radar monitoring systems

      6. Industrial control

      7. Aerospace

      8. Telecommunications

      9. Medical devices

      Conclusion:

      In PCB production, Heavy copper PCBs require special processes, are difficult to operate, and have certain technical barriers, so the production cost of Heavy copper PCBs is higher than other ordinary circuit boards. Although the price is not cheap, the quality and service are the best.

      BEST Technology has more than 18 years of PCB manufacturing experience. Focusing not only on fast PCB prototyping and PCB assembly, but also on small and medium batch PCB manufacturing, customer satisfaction is our goal, we will do our best to manufacture your circuit boards in the highest quality to meet your needs, and are committed to complying with the most stringent standards in PCB manufacturing and assembly. ‌

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      The influence of copper thickness on PCB
      Monday, August 19th, 2024

      Copper thickness has a very important impact on the performance of PCB, and PCBs with different copper thicknesses also have very different applications. The fundamental reason why copper is widely used in circuit board manufacturing is its electrical conductivity, so different copper thicknesses correspond to different electrical conductivities. In addition, copper also has low resistance and thermal stability.

      Why fill PCB with copper?

      The main purpose of using copper to fill PCB (Printed Circuit Board) is to improve the electrical conductivity of the circuit board, enhance mechanical strength and stability, protect the circuit board from oxidation or corrosion, and improve heat dissipation capabilities. ‌

      The influence of copper thickness on PCB

      As an excellent conductive material, copper plays a vital role in PCB design. By covering the surface of the PCB with copper foil, the conductive performance of the circuit board can be significantly improved and the connection between various components can be ensured to be more stable and reliable.

      Copper foil itself has high mechanical strength and stability, which can effectively prevent PCB from being damaged or deformed due to the influence of the external environment. The corrosion resistance of copper foil can also protect the circuit board from oxidation or corrosion, thereby extending the service life of the circuit board and ensuring its stability and reliability during work.

      Since metal has good electrical and thermal conductivity, copper coating can increase the heat dissipation surface area of the PCB, help distribute heat evenly, and prevent the generation of local high-temperature areas. This can not only reduce local heat concentration, but also reduce the temperature gradient of the heat source and improve heat dissipation efficiency.

      To sum up, the role of copper-filled PCB is multi-faceted. It can not only improve the conductivity and mechanical stability of the circuit board, but also protect the circuit board from environmental influences, while enhancing the heat dissipation capacity and ensuring the stable operation of electronic equipment. and long-term use‌.

      Is a thicker PCB copper better?

      The copper thickness of PCB is not as thick as possible, but the appropriate copper thickness needs to be selected according to the design requirements and actual application of the circuit board. ‌

      The importance of copper thickness in PCB manufacturing cannot be ignored because it directly affects the conductive performance, heat dissipation performance, mechanical strength and signal integrity of the circuit board. Proper copper thickness can provide good electrical and thermal conductivity while ensuring the reliability and stability of the circuit board.

      Although an excessively thick copper layer can improve current carrying capacity and heat dissipation performance, it will also increase cost and weight, which may lead to serious glue flow and increased processing difficulty. Therefore, when selecting copper thickness, factors such as circuit board design requirements, application environment, and cost need to be comprehensively considered.

      During the PCB design and manufacturing process, the optimal copper thickness should be selected based on specific application requirements and cost considerations to achieve optimal circuit performance, heat dissipation, and mechanical strength‌.

      How thick is the copper on a 1 ounce copper PCB?

      The thickness of 1 ounce of copper on a PCB is 35 microns. ‌

      The influence of copper thickness on PCB

      In the PCB industry, ounces (oz) are the unit used to express copper foil thickness, not weight. Specifically, the thickness of 1oz of copper refers to the thickness achieved by spreading 1oz of copper evenly over an area of 1 square foot.

      According to different information, the thickness of 1oz copper can be obtained by different calculation methods, but the generally accepted value is that 1oz copper is equal to 1.4mil (milliinch), which is equivalent to 35 microns. Therefore, whether in international standards or practical applications, the thickness of 1oz copper on PCB is usually considered to be 35 microns.

      In addition, the copper thickness of the PCB has a direct impact on the circuit board’s current carrying capacity, heat dissipation, reliability and other performance indicators. Commonly used PCB copper thickness specifications include 1oz, 2oz, 3oz, 4oz, 5oz, 6oz, etc., which correspond to different copper layer thicknesses. The copper layer thickness of 1oz is 35 microns, 2oz is 70 microns, and so on, 6oz is 210 microns. . These specifications provide the basis for selecting different copper thicknesses based on specific application needs to meet different electrical performance and physical requirements.

      What is the conventional PCB copper thickness?Thick copper plate, FPC

      ‌Regular PCB copper thickness is 1oz (35μm). When the thickness of the copper foil reaches or exceeds 2oz, such a PCB board is defined as a thick copper board; for flexible circuit boards (FPC), the copper thickness also has different specifications, for example, 0.5oz copper thickness is used for flexible circuit boards is being manufactured. ‌

      The influence of copper thickness on PCB

      In PCB manufacturing, the choice of copper thickness is determined based on specific application requirements. Common copper thickness classifications include:

      1. ‌1oz copper thickness: ‌

      This is the most common and standard copper foil thickness and is widely used in everyday electronic devices and general applications. 1oz (ounce) means 1 ounce of copper foil weighs 1 square foot. In the PCB manufacturing process, 1 ounce corresponds to a copper foil thickness of approximately 35 microns, which has good electrical and thermal conductivity.

      2. ‌2oz copper thickness: ‌

      Copper foil of this thickness is usually used in circuits that require higher current carrying capabilities, such as power amplifiers, high-power LEDs, etc. 2oz copper thickness corresponds to a copper foil thickness of approximately 70 microns, which has better performance in electrical conductivity and heat dissipation than 1oz copper thickness.

      3. ‌0.5oz copper thickness: ‌

      This thinner copper foil thickness is suitable for some light and small electronic products, such as electronic watches, mobile phones, etc. 0.5oz (18μm) copper foil is suitable for equipment that has strict requirements on circuit board size and weight.

      How to choose PCB copper thickness?

      Choosing PCB copper thickness depends primarily on the board’s purpose, current requirements, signal integrity requirements, cost budget, and manufacturing process capabilities.

      1. ‌Circuit board usage and current requirements‌: For circuit boards that need to handle large currents, such as power boards, it is recommended to use thicker copper foil, such as 2oz (about 70μm) or 3oz (about 105μm). For signal transmission, a copper thickness of 1oz (~35μm) is usually sufficient. Ordinary double-sided boards generally use 1oz copper thickness, while multi-layer boards generally use 1/2oz, 1/3oz copper thickness for the inner layer, and 1oz, 1/2oz, 1/3oz copper thickness for the outer layer.

      2. Signal integrity requirements: For high-density interconnect (HDI) boards or high-frequency circuits, thinner copper foil may be required to reduce parasitic effects and ensure signal integrity.

      3. ‌Cost considerations‌: The thicker the copper foil, the higher the cost is usually.

      4. Environmental factors: For PCBs in extreme working environments (such as high temperature, high humidity or high vibration environments), the thickness of the copper foil may need to be adjusted to enhance the stability and durability of the circuit.

      In summary, selecting PCB copper thickness is a process that comprehensively considers multiple factors and needs to be determined based on specific application scenarios and design requirements.

      What is the difference between different copper thicknesses on PCB?

      ‌The main differences between different copper thicknesses on PCBs are their conductive properties, load-bearing capacity, anti-interference performance, cost and manufacturing difficulty. ‌

      The influence of copper thickness on PCB

      ‌Outer copper thickness‌ is commonly used for circuit board routing and connections, and its selection depends on the application requirements and design needs of the circuit board. The outer copper thickness range is generally between 1-5oz, and the more common ones are 1oz, 2oz, 3oz and 4oz. The thicker the outer copper layer, the stronger the circuit board’s load-bearing capacity, and the better its anti-interference performance and electrical conductivity. But at the same time, the increase in the thickness of the outer copper layer will also lead to an increase in cost and manufacturing difficulty.

      ‌Inner layer copper thickness‌ is used for internal connections and signal transmission of the circuit board, and its selection also depends on the application requirements and design needs of the circuit board. The thickness of the inner copper layer generally ranges from 0.5-2oz, with the more common ones being 0.5oz, 1oz, and 2oz. If the circuit board needs to transmit high-speed signals, a larger inner copper thickness should be selected. The increase in the thickness of the inner copper layer will also lead to an increase in cost and manufacturing difficulty.

      ‌Copper Thickness Standard‌According to international standards, the copper thickness of PCB boards can be divided into standard copper thickness (such as 1oz and 2oz) and non-standard copper thickness (such as 0.5oz, 3oz and 4oz). In practical applications, some special PCB boards may require higher copper thickness, such as high-power LED lights, electronic high-frequency circuits, etc.

      To sum up, the choice of different copper thicknesses is to meet specific circuit board design needs, including conductive performance, anti-interference performance and other requirements. At the same time, the choice of copper thickness also needs to consider aspects such as cost and manufacturing difficulty.

      Conclusion:

      By controlling the thickness of copper on the PCB to meet different usage requirements, applications that require large currents will naturally require PCBs with thicker copper foils. However, PCBs that require thicker copper foils are a great test of the capabilities of PCB manufacturers. BEST Technology has accumulated rich production experience in the PCB manufacturing industry and has many years of manufacturing experience for PCBs with different copper thicknesses. We can meet any PCB copper thickness requirements.

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      Let you know about PCB copper layer thickness
      Friday, August 16th, 2024

      In the printed circuit board industry, the most common way to express the copper layer thickness on a PCB is in ounces (oz). 1oz means 1oz of copper evenly covers an area of 1 square foot, which is about 1.4mil. It uses the weight of the tissue area to express the average thickness of the copper foil. Expressed in terms of formula, 1oz=28.35g/FT2 (FT2 is square feet, 1 square foot = 0.09290304 square meters).

      What is the standard thickness of a copper layer on a PCB?

      In the manufacture of printed circuit boards (PCBs), the thickness of the copper layer is an important parameter that directly affects the electrical performance and reliability of the circuit board. Depending on the application requirements, the thickness of the copper layer can vary within a certain range. Generally speaking, the conventional copper layer thickness is between 1-35μm, with 35μm being the most commonly used thickness. For some applications with high reliability requirements, the copper layer thickness may reach more than 50μm.

      The selection of the thickness of the copper layer is a decision-making process that takes into account a variety of factors, including the conductivity, heat dissipation, mechanical strength, cost and manufacturing difficulty of the circuit board. A larger copper thickness can reduce resistance and improve the conductivity and heat dissipation of the circuit board, but it will also increase material costs and production difficulties. Therefore, when designing PCB boards, engineers need to select a suitable copper thickness standard range based on specific application scenarios and design requirements to ensure the performance and reliability of the circuit board.

      1oz copper thickness in mm = 0.035mm

      0.5 oz copper thickness in mm = 0.0175mm

      1.5 oz copper thickness in mils = 0.0525mm

      2 oz copper thickness in mils =  0.07mm‌

      How thick is PCB copper after plating?

      PCB printed circuit boards are usually bonded to glass epoxy substrates with a layer of copper foil, usually 18, 35, 55 and 70 microns thick. The most commonly used copper foil is 35 microns thick.

      The copper foil used by PCB manufacturers is generally 35~50 microns thick, and some are thinner than this, such as 10 microns, 18 microns, and thicker such as 70 microns. The thickness of the composite copper foil on a 1~3 mm thick substrate is about 35 microns. The thickness of the composite copper foil on a substrate with a thickness of less than 1MM is about 18 microns, and the thickness of the composite copper foil on a substrate with a thickness of more than 5 mm is about 55 microns.

      The copper layer thickness of PCB (printed circuit board) can be adjusted according to different needs and designs. Common copper layer thicknesses include 1oz (35μm), 2oz (70μm), 3oz (105μm), and other thicker options. For most applications, a copper layer thickness of 1oz is sufficient and suitable for general signal transmission. ‌For circuit boards that need to carry large currents, such as switching power supplies, a copper layer thickness of 2oz or higher is usually used. ‌In addition, there are some special cases where manufacturers provide extremely heavy copper up to 20 oz/ft2 (26.8 mils or 0.34 mm) to meet special needs. ‌

      When choosing the thickness of the copper layer, factors such as the purpose of the circuit board and the magnitude of the signal voltage and current need to be considered. ‌For example, for circuit boards that require excessive current, a copper thickness of 70μm or 105μm may be used. ‌For thin laminates that require ultra-high density patterns, a copper thickness of 12μm may be used. ‌Therefore, the specific thickness of the PCB after copper plating is determined according to design requirements and specific applications.‌

      How thick is 2 oz copper for PCB?

      If 1 ounce (28.35 grams) of copper were flattened to evenly cover a surface area of 1 square foot (0.093 square meters), the resulting thickness would be 1.37mils (0.0348mm). A conversion chart for different units of measurement can be found below.

      PCB copper layer thickness 

      What is the difference between different copper thicknesses in PCB?

      ‌Copper is an excellent conductive material, and the thickness of the copper layer directly affects the conductive effect of the circuit board. ‌Thicker copper layers can provide lower resistance, reduce signal transmission losses, and are particularly suitable for high-frequency and high-speed digital circuits. ‌

      During the operation of electronic equipment, good heat dissipation is a key factor in ensuring the performance and life of components. ‌Thicker copper layers can conduct and dissipate heat more effectively, preventing components from overheating. ‌

      In high-power electronic devices, thicker copper layers can carry larger currents, avoiding burnout or performance degradation caused by excessive current.

      Below is the conductivity corresponding to different copper thicknesses.

      PCB copper layer thickness 

      How thick is high current PCB copper?

      In PCB design, copper thickness (also called copper thickness) is an important parameter, which directly affects the performance indicators of the circuit board such as current carrying capacity, heat dissipation and reliability. For PCBs that need to withstand high currents, such as high-power LED light strips, power circuit boards, high-power motor control boards or high-power inverter control boards, thicker copper layers are usually used to increase current carrying capacity.

      PCB copper layer thickness 

      Different uses have different copper foil thicknesses. Common 0.5oz, 1oz, and 2oz are mostly used in consumer and communication products. Thick copper products above 3oz are mostly used for high currents, such as high-voltage products and power boards.

      The thickness of copper foil (track width) will affect the current size. Although there is a formula that can directly calculate the maximum current carrying capacity of copper foil, it is not so simple when actually designing the circuit. Therefore, the safety factor should be fully considered during the design.

      How thick is the copper in a flex PCB?

      The thickness of copper foil in flexible PCB is generally 18μm, 35μm, 55μm and 70μm. These thickness specifications are suitable for different types of circuit board requirements, among which 35μm is the most commonly used copper foil thickness.

      PCB copper layer thickness 

      For flexible PCB, the choice of copper foil thickness depends on the specific purpose of the circuit board and the size of the signal voltage and current. For example, for PCBs that require excessive current, some parts will use 70μm copper thickness, while for signal transmission, 1oz (35μm) thickness is usually sufficient. In addition, for substrates of different thicknesses, the thickness of copper foil is also different. For example, the thickness of the composite copper foil on a 1mm thick substrate is about 18μm, and on a substrate thicker than 5mm, the thickness of the composite copper foil is about 55μm.

      Conclusion:

      PCBs for different usage scenarios correspond to different thicknesses of copper, and its thickness directly affects the conductive effect of the circuit board. If the copper layer is too thin, the conductivity may decrease, resulting in signal transmission attenuation or current instability. If the copper layer is too thick, although the conductivity will be very good, it will increase the cost and weight of the circuit board and easily lead to serious glue flow. In PCB manufacturing, it is necessary to select the appropriate copper thickness according to the design requirements and actual applications of the circuit board to achieve the best conductive effect.

      BEST Technology is a professional PCB circuit board manufacturer with a large area of site and equipped with useful and experienced production personnel. Corresponding to different thicknesses of copper, we have rich production and processing experience. We can meet the requirements of any circuit board copper layer thickness.‌

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      Drone Circuit Board: What It Is and How to Make a Drone PCB Board?
      Friday, August 16th, 2024

      What is a Drone Circuit Board?

      A drone circuit board refers to the electronic component board installed in a drone that controls and manages its various functions. It serves as the core control system of the drone, similar to how a brain functions in the human body. The drone circuit board controls all operations, including flight, photography, and video recording. It is the central system that coordinates all activities.

      Depending on different functions and application scenarios, drone circuit boards can be classified into various types, such as flight control boards, video transmission boards, and power control boards. Among these, the flight control board can be considered a type of drone circuit board but is not equivalent to it. The flight control board mainly controls parameters such as flight direction, altitude, and speed, and adjusts the drone’s posture to ensure stable flight. The drone circuit board, however, not only controls flight but can also implement auxiliary functions such as GPS positioning and image transmission.

      What Board is Used in Drones?

      In drone design, the two most common types of circuit boards are rigid-flex boards and traditional PCB boards. Rigid-Flex PCB is a hybrid type of PCB that combines rigid and flexible circuit boards. It allows the board to bend and fold in tight spaces, which is particularly useful for compact drones that require a highly integrated design. Moreover, rigid-flex boards are lightweight and thin, which is advantageous for drone designers looking to enhance flight time and stability.

      Traditional PCB Boards are another common type of circuit board used in drone design. These boards have strong mechanical strength, making them suitable for the core control units in drones, such as flight control boards and ESC boards (Electronic Speed Controllers).

      Below are the main types of circuit boards commonly found in drones:

      Control Circuit Board

      The control circuit board is one of the most important boards in a drone. It typically consists of the main control chip, sensors, and electronic speed controllers (ESC). The main control chip acts as the brain of the drone, receiving wireless signals and controlling the flight posture and movement based on user commands. Sensors can detect the drone’s position and motion in real-time, ensuring stable flight control. The ESC adjusts the motor speed and direction, which directly impacts the drone’s flight.

      Power Supply Circuit Board

      The power supply circuit board is responsible for providing power to the drone, ensuring proper voltage and current. It must prevent issues like overcurrent, overvoltage, and overheating to maintain the drone’s performance.

      Navigation Circuit Board

      The navigation circuit board determines the drone’s position and direction, with the GPS module as the core component. GPS helps obtain satellite signals, calculating important information such as latitude, longitude, and altitude, to ensure precise navigation and positioning. The board may also include other sensors like barometers, gyroscopes, and accelerometers to enhance navigation accuracy.

      Communication Circuit Board

      The communication circuit board typically includes WiFi, Bluetooth, and 4G/5G modules, which allow the drone to connect with ground control stations or user devices for data transmission, remote control operations, and video streaming.

      Why Use a Drone Circuit Board?

      Besides the central chip, drone circuit boards serve many critical functions, such as power management and signal transmission. Let’s take a closer look at their functionality:

      Power Management

      The power management chip on a drone circuit board controls and regulates the power supply. Unlike regular circuit boards, the power management module in drones must be efficient, low-power, and lightweight. Since drones often need to fly for hours, improper design of the power management module can severely impact flight time and energy utilization.

      Collecting data

      The sensor chip on the drone circuit board is responsible for collecting data, such as GPS location, barometric pressure, and posture. The sensor chip processes data from wireless sensors and transmits it to the control chip for decision-making.

      Control the drone

      The control chip is the most vital part of the drone circuit board, managing and coordinating all aspects of the drone’s operation, including GPS navigation, servos, and motors. The microprocessor in the control chip uses algorithms to control flight while processing real-time sensor data.

      Data Transmission

      When capturing aerial photos or videos, the drone needs to send the recorded data to ground devices. The data transmission chip on the drone circuit board ensures that this information is transmitted to ground equipment. Many drones also support wireless network connections for seamless communication.

      How to Make a Drone PCB?

      To make a drone PCB, you’ll need to prepare the following materials:

      • STM32F405RGT6 microcontroller, which is stable and suitable for various drone applications.
      • 2.4G CC2500 wireless module based on the UART protocol for data communication with the remote control.
      • Sensors like accelerometers, gyroscopes, magnetometers, barometers, GPS, etc., to provide sensor fusion for precise drone control.
      • Power Module
      • Other components including resistors, capacitors, diodes, voltage regulators, and other basic circuit components.

      Here is the way to create the drone PCB step by step:

      1. Design

      You can use PCB software to design the schematic and PCB layout, determining key parameters like circuit connections and component placement.

      2. Printing and Etching

      Print the designed circuit board pattern onto transparent stickers and attach them to copper sheets. After etching and removing the stickers, the circuit board will be ready.

      3. Soldering

      Solder the components onto the circuit board. It’s essential to leave adequate pads for soldering during the design phase.

      4. Testing

      Test the soldered circuit board to ensure normal functioning of the circuits.

      What Should We Consider When Designing a Drone PCB?

      • Make sure enough power, ground, and data lines are allocated to each component to avoid signal interference and noise.
      • Take measures to protect components from static electricity during soldering.
      • Write clear and standardized comments in your program for easier modifications and debugging later.
      • Double-check that the board’s connections are in the correct order to prevent damage to the control board.

      Is a Fuse Board the Same As a Distribution Board?

      No, a fuse board and a distribution board serve different purposes in a drone’s electrical system.

      Fuse board is designed to protect your components from power surges or short circuits. It contains fuses that blow if too much current flows through them, cutting off power to prevent damage.

      Distribution board is simply distributes power from the battery to different components of the drone, such as the ESCs and flight controller. It doesn’t have the protective features of a fuse board.

      In some designs, both can be combined into one board, but their functions remain distinct.

      How can I Increase my Drone Power?

      Increasing your drone’s power can improve performance, allowing it to carry more weight or fly faster. You can use below ways to increase the power:

      • Upgrade motors
      • Increase battery capacity
      • Use better propellers
      • Optimize power distribution

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      hdi printed circuit board,hdi pcb manufacturer
      Wednesday, August 14th, 2024

      What is hdi pcb?

      HDI stands for High Density Interconnect, which refers to high-density interconnect technology. HDI circuit board is a high-end printed circuit board with very high circuit density and complexity, which can achieve high-speed signal transmission and reliability design. The main features of HDI circuit board are multi-layer circuit, thin plate, small aperture, dense wiring and fine circuit. It is widely used in mobile phones, computers, network communications, automotive electronics and other fields. Bestpcb is a professional HDI manufacturer with 18 years of HDI manufacturing experience.

      What are the advantages of hdi pcb

      1. Higher line density: HDI PCB can support more circuit tracks, arrange more electronic components in a limited space, and achieve high-density interconnection.
      2. Smaller device spacing: The micro-hole technology of HDI PCB allows smaller spacing between components, which is suitable for compact design.
      3. Improve signal integrity: The advanced stacking layer structure is adopted to provide better signal transmission quality and reduce signal interference.
      4. Improve reliability: The manufacturing process of HDI PCB improves the mechanical strength of the board, making it more durable and suitable for demanding application environments.
      5. Improve circuit integration: More line connections and component arrangements are achieved in a limited circuit board space to meet the needs of modern products that are thin and compact.
      6. Enhance signal transmission efficiency: The use of advanced wires and connection methods can increase the operating speed of electronic devices and reduce energy consumption.
      7. Support more complex system design: High-density connection capabilities provide support for complex system design and give full play to the performance of electronic devices. ‌
      8. Promote innovation in the electronics industry: The application of HDI technology has promoted the innovation and development of the electronics industry, making electronic equipment more intelligent and efficient. ‌
      9. Smaller size: It can complete a large number of circuit connections in a smaller space, meeting the needs of electronic products for lightness and portability. ‌
      10. Higher signal transmission speed: The high-density line design allows signals to be transmitted quickly in a short time, improving the system operation speed and response speed.

      Why does HDI PCB need via filling and plating?

      ‌Via filling plating plays a vital role in ‌HDI PCB manufacturing, with the main purpose of improving ‌electrical performance, connection reliability, operating frequency, and avoiding electromagnetic interference. This technology fills the blind holes of HDI PCB with conductive materials through the electroplating process to form a conductive path, which improves the performance and reliability of electronic equipment.

      1. Improve electrical performance: Via filling plating can improve the electrical performance of HDI PCB, especially in high-frequency circuit board design, which is crucial for improving connection reliability, operating frequency and avoiding electromagnetic interference.
      2. Via plugging and electrical interconnection in one step: Via filling plating technology combines via plugging and electrical interconnection, avoiding the defects caused by resin via filling, and also avoiding the CTE difference caused by other materials via filling.
      3. Improve efficiency: Compared with resin via filling or other materials via filling, via filling plating has a simpler process and higher efficiency.
      4. Process flow and technical challenges of via filling plating
      5. Process flow: including steps such as tank preparation, setting of electroplating process control parameters, and analysis of potion addition.
      6. Technical challenges: including positioning accuracy issues and electroplating quality issues, which need to be solved by strictly controlling parameters such as electroplating time and current density.

      Application scenarios of hole filling electroplating

      First-order HDI: Suitable for electronic devices with less complex circuits.
      Second-order and above blind hole electroplating copper filling: Suitable for more complex electronic devices, such as mobile phones, laptops, etc.
      Comparison between hole filling electroplating and full-board electroplating
      Full-board electroplating: Although it can provide a uniform surface copper thickness distribution, it may encounter the problem of residual dry film on the board surface or in the hole during pre-treatment, resulting in some areas unable to be plated with copper. In addition, the etching process after full-board electroplating may cause quality defects such as side etching and fine lines.
      Hole filling electroplating: Compared with full-board electroplating, hole filling electroplating is more accurate in filling blind holes, avoiding the problems that may be encountered in full-board electroplating, while simplifying the process and improving efficiency.

      Materials of HDI PCB

      The materials of HDI PCB mainly include coated copper foil (RCC), prepreg, copper foil, etc.

      Resin-coated copper foil (RCC): This is a material that coats a special resin film layer on electroplated copper foil, used for HDI insulation layer. The characteristics of RCC include no glass dielectric layer, easy laser and plasma micro-hole forming, extremely high peel strength and good toughness, suitable for micro-narrow line etching. Laser drilling is performed on RCC, and the aperture shape formed is an inverted trapezoid, and the general aperture size is 0.076-0.10 mm. The use of RCC makes HDI PCB more widely used in small portable products, such as mobile phones, digital cameras, laptops, etc.

      Prepreg and copper foil: These are basic materials in HDI PCB manufacturing, there are no special requirements, and they are suitable for different types of HDI PCB structures. The inner layer circuits are generally 1 ounce copper thick, while the outer layer circuits are plated with half an ounce of base copper to 1 ounce of finished copper thickness. The thickness of the board is usually thinner to meet the miniaturization requirements of HDI PCB.

      Other materials: In addition to the main materials mentioned above, the manufacture of HDI PCBs may also involve other materials, such as FR4, PI (polyimide), BT, etc. These materials are selected according to specific application requirements. For example, FR4 has good electrical and mechanical properties and is suitable for most general applications; PI has higher heat resistance and chemical corrosion resistance, and is suitable for high temperature, high humidity and strong acid and alkali environments, but it is more expensive and difficult to process; BT combines good electrical properties, mechanical properties and thermal stability, and is suitable for application scenarios that require higher heat resistance.

      Classification of HDI circuit boards

      HDI circuit boards are mainly divided into first-order, second-order, third-order, high-order (including fourth-order and above) and Anylayer HDI. ‌

      1. First-order HDI circuit boards mainly include single-sided or double-sided micro-hole processes, and the circuit layer has only one layer. ‌This type of HDI circuit board is suitable for applications with high requirements on cost and space, such as consumer electronics. ‌
      2. Second-order HDI circuit boards contain two circuit layers, which are more complex but also more powerful than first-order HDI circuit boards. They can handle higher signal frequencies and are suitable for applications that require high performance, such as high-end communication equipment and computer hardware. ‌
      3. Third-order HDI circuit boards contain three circuit layers. They are the most complex type at present. They can handle the highest signal frequency and the maximum data transmission rate. They are usually used in applications that require the highest performance, such as aerospace and military equipment. ‌
      4. High-order HDI (including fourth-order and above) The applications of third-order or fourth-order HDI in electronic terminal products are more, while those above fourth-order are mostly converted to Anylayer structure. ‌
      5. Anylayer HDI refers to HDI of any order/any layer. Compared with PCB boards with traditional lamination processes, HDI can reduce costs to a lower level when the stacking density exceeds eight layers. It also has higher electrical performance and signal accuracy, and significantly improves the performance of electromagnetic waves and radio frequency interference, electrostatic discharge and heat conduction in interconnection and relay transmission.

      HDI PCB Process Flow

      The process flow standards of HDI PCB mainly involve the application and processing technology of high-density interconnection technology (High Density Interconnection Technology, HDI for short), including first-order, second-order and third-order processes. Specifically, the HDI PCB process flow includes the following key steps and characteristics:

      First-order process (1+N+1): This is a basic high-density interconnection technology that manufactures multi-layer boards through build-up and micro-blind via technology.

      Second-order process (2+N+2): Further development on the basic technology, adding more layers and complexity.

      Third-order process (3+N+3): Represents the highest stage of HDI technology, with extremely high layers and interconnection density

      Differences between HDI PCB and ordinary PCBs

      1. Differences in circuit design:
        HDI PCB adopts a more sophisticated circuit design, with smaller line width and spacing, and smaller aperture, which can integrate more electronic components and realize more complex circuit functions. ‌
        The blind, buried and stacked hole designs of HDI PCB greatly improve the utilization rate and signal transmission performance of the circuit board.
      2. Differences in manufacturing process:
        The manufacturing process of HDI PCB is more complicated, requiring high-precision processes such as laser drilling technology, hole filling electroplating technology and photolithography technology.
        The manufacturing cost of HDI PCB is relatively high, but the performance and reliability are also higher. ‌
      3. Differences in application:
        Due to its high density and high performance, HDI PCB is widely used in high-end electronic products, such as smartphones, tablets, high-end communication equipment, etc.
        Ordinary PCB is mainly used in low-end electronic products and general electronic equipment.
      4. Characteristics and application scenarios of HDI PCB:
        HDI PCB has high-density wiring, multi-layer structure, high-precision manufacturing process and excellent electrical performance, which can meet the extremely high requirements of high-end electronic products for size, weight, performance and reliability.
        HDI PCB is widely used in smart phones, tablet computers, high-end communication equipment and other fields, promoting the continuous development and upgrading of electronic products.

      Application of HDI PCB

      HDI PCB (High Density Interconnection Printed Circuit Board) is widely used in multiple industries, including medical equipment, mobile phones, laptops, automotive electronics, computer industry, and future 5G technology fields

      1. Medical equipment: The application of HDI PCB in medical equipment, such as sphygmomanometers and ultrasonic imaging systems, achieves accurate measurement of blood pressure and high-definition imaging of the internal structure of the body, providing patients with timely and accurate diagnosis and treatment information. ‌
      2. Mobile phone industry: With the increasingly miniaturized design of mobile phones, HDI PCB is widely used in transceiver modules, motherboards, SIM card interfaces, fingerprint recognition modules and other parts of mobile phones due to its high density, high quality and high reliability. ‌
      3. Computer industry: In the computer industry, the application of HDI PCB improves the performance of computers, especially in the fields of high-speed algorithms and multimedia applications, and adapts to the miniaturization trend of computer equipment2. ‌
      4. Automotive electronics: HDI PCB has broad application prospects in the field of automotive electronics. In addition to the dominant mobile phone market, it also involves multiple fields such as automobiles, modules and artificial intelligence, demonstrating its key role in complex electronic systems. ‌
      5. Future development trends: With the advent of 5G technology, the demand for HDI PCB will continue to increase, requiring higher speeds and frequencies while adapting to smaller and thinner device designs. Research new micro HDI PCB boards to adapt to future development trends. ‌

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      HASL Lead Free vs ENIG: Understanding Their Differences
      Tuesday, August 13th, 2024

      When it comes to PCB surface finishes, choosing the right one is essential for the longevity and performance of your circuit board. Among the many options available, two of the most popular are Hot Air Solder Leveling (HASL) and Electroless Nickel Immersion Gold (ENIG). These two methods offer distinct advantages depending on the application, and understanding their differences can help you select the best finish for your project.

      HASL Lead Free vs ENIG: Understanding Their Differences

      What Does HASL Stand For?

      HASL stands for Hot Air Solder Leveling. It is a surface finish process used in PCB manufacturing. The term describes the method where solder is applied to the copper pads on a PCB and then leveled using hot air to ensure even coating. HASL is widely used because of its simplicity and effectiveness in providing a reliable solderable surface.

      What Is HASL in PCB?

      In PCB manufacturing, HASL is a surface finish applied to the exposed copper pads to protect them from oxidation and to provide a good surface for soldering components. The HASL process involves dipping the PCB into molten solder, typically composed of a lead-free alloy, and then using hot air to remove excess solder, ensuring a smooth and even layer. This finish is particularly valued for its excellent solderability and cost-effectiveness.

      HASL Lead Free vs ENIG: Understanding Their Differences

      Characteristics of Hot Air Solder Leveling

      Hot Air Solder Leveling is a widely used surface finish in PCB manufacturing due to its unique set of characteristics that make it suitable for various applications. Below are the key attributes that define HASL:

      1. HASL provides one of the most solderable surfaces available for PCB assembly. The molten solder applied during the HASL process creates a coating that is highly receptive to soldering, making it easy to attach components.

      2. Compared to other surface finishes like ENIG or OSP, HASL is generally more affordable.

      3. The solder coating provided by HASL serves as a protective layer for the copper pads on the PCB. This layer helps prevent oxidation and corrosion.

      4. Variability in coating thickness. The hot air leveling process can result in uneven distribution of solder, leading to variations in thickness across the PCB. While this might be a drawback for designs requiring fine-pitch components or precise tolerances, it is often acceptable in less demanding applications where slight variations are not critical.

      5. Thermal resistance. The solder layer provided by HASL can withstand multiple thermal cycles during the PCB assembly process, such as during solder reflow.

      6. The HASL process creates a strong bond between the solder and the underlying copper pads.

      What Is the HASL Method?

      The HASL coating process is a critical step in PCB manufacturing, designed to protect the exposed copper pads and good solderability during the assembly of electronic components. The process is under several steps, each carefully controlled to achieve a uniform and reliable coating. Here’s a detailed look at how HASL is applied to a PCB:

      1. Pre-Cleaning the PCB

      The HASL process begins with thoroughly cleaning the PCB to remove any contaminants such as oxidation, oils, or residues from previous manufacturing steps. This is typically done using a combination of chemical cleaning agents and mechanical scrubbing.

      2. Flux Application

      After cleaning, a layer of flux is applied to the PCB. Flux is a chemical agent that serves multiple purposes: it removes any remaining oxidation from the copper pads, improves the wetting of the solder, and helps the solder adhere more effectively to the copper. The type of flux used can vary, but it must be compatible with the solder alloy to ensure a reliable coating.

      3. Solder Bath Dipping

      The PCB is then dipped into a bath of molten solder. For lead-free HASL, the solder typically consists of a tin-silver-copper (SAC) alloy, which is heated to a temperature between 240°C and 260°C (464°F to 500°F). The molten solder covers the entire surface of the PCB, including the copper pads and through-holes, forming a protective layer.

      4. Hot Air Leveling

      Once the PCB is removed from the solder bath, it immediately undergoes the leveling process. The board is passed through a pair of hot air knives positioned on either side. These knives blow high-pressure, heated air across the surface of the PCB, removing any excess solder and ensuring a uniform layer remains on the pads.

      5. Cooling

      After leveling, the PCB is cooled to solidify the solder coating. This cooling is typically done using an air or water-based cooling system, depending on the specific requirements of the manufacturing process. Rapid cooling can sometimes introduce stresses into the solder layer, so the cooling rate must be carefully controlled to avoid defects like cracking or warping.

      6. Post-Process Cleaning

      In some cases, the PCB may undergo a final cleaning step to remove any flux residues or other contaminants that might remain after the HASL process. And then testing and inspection.

      What Is the Difference Between HASL and ENIG Finish?

      While both HASL and ENIG are popular PCB surface finishes, they differ significantly in their composition, application, and performance:

      CharacteristicHASLENIG
      CostLower cost, suitable for budget-sensitive projectsHigher cost, but justifiable for high-reliability needs
      SolderabilityExcellent, but may vary with coating thicknessConsistent, even for fine-pitch components
      DurabilityReasonable, but less effective in harsh environmentsSuperior, with excellent corrosion resistance
      Thermal PerformanceGood, but uneven surface might cause issuesExcellent, with consistent performance in high-heat scenarios
      Best Suited ForGeneral-purpose electronics, consumer productsHigh-reliability applications, aerospace, medical, and high-density PCBs
      Surface FlatnessMay have uneven surface, less ideal for fine-pitch componentsExtremely flat surface, ideal for precise component placement
      Environmental ImpactLead-free HASL is environmentally safer, but traditional HASL uses lead which is harmfulEnvironmentally friendly, as it doesn’t use lead or other harmful materials
      Shelf LifeShorter shelf life due to potential oxidation over timeLonger shelf life due to gold’s resistance to oxidation
      ReworkabilityEasier to rework due to the nature of solderMore challenging to rework due to hard nickel layer

      HAL vs. HASL

      HAL (Hot Air Leveling) and HASL (Hot Air Solder Leveling) are terms often used interchangeably, but they can refer to slightly different processes. HAL is a broader term that encompasses any method of leveling solder using hot air. In contrast, HASL specifically refers to using solder to coat the PCB’s surface. Essentially, all HASL processes are HAL, but not all HAL processes are HASL.

      What Is the Composition of HASL?

      At present, the solder of lead-free solder alloy hot air leveling is mainly Sn-Cu-Ni+Ge (germanium) or Sn-Cu-Ni+Co (cobalt). The components of Sn-Cu-Ni+Ge (Germanium) in the OPA2544T are Sn, 0.7% Cu, 0.05% Ni and Ge with a nominal content of 65×10-6. Germanium can not only prevent the growth of oxides, but also prevent the solder joints on the PCB pad coating surface from yellowing and tarnishing during the HASL process and subsequent reflow welding and wave soldering processes. In addition, germanium can also inhibit the formation of slag in lead-free wave soldering.

      The biggest problem in the lead-free HASL process is the problem of sinking copper in the tin tank during the use of the equipment.

      The typical operating temperature range of the HASL process is 265 to 275 ° C, and this temperature range can be used for almost all actual manufactured laminates. At this temperature, even CEM1, there is no problem of delamination and degradation. However, the actual process temperature increases with the increase of copper composition in the tin tank. When the copper composition is 0.3% higher than the optimal value of 1.2%, then the welding temperature must be increased to 285 ° C, which is not the laminate can withstand. Although a copper-free solder alloy can be added to reduce the copper content in the tin tank, it is difficult to control the proportion.

      The so-called “freeze-drying” method can also be used. When the tin lead eutectic solder (63Sn-37Pb) temperature drops to about 190℃, the melting tin copper intermetallic compound (Cri6Sn5) will be “freeze-dried”. In high-density lead solders, Cu6Sn5 floats on the surface of the molten solder and can be skimmed out using a slotted spoon. However, in lead-free solder, Ct16SIl5 is denser than lead-free solder, and CLJ6Sn5 will settle to the bottom of the tin tank. There is a mechanism to reduce the temperature to about 235 ° C (about 8 ° C higher than the melting point temperature), the tin tank shut down for at least two hours, preferably all night, at this time, most of the alloy is still in a molten state, you can design special tools, from the bottom of the tin tank out of the precipitation of Cr16Sn5, but it is still very difficult.

      What Is the Minimum Pitch for HASL?

      The minimum pitch for HASL refers to the smallest distance between two adjacent pads that can be reliably soldered using the HASL process. Due to the nature of the hot air leveling process, which can create uneven surfaces, HASL is generally not recommended for very fine-pitch components. The minimum pitch is typically around 0.65mm, but it can vary depending on the specific requirements and the quality of the HASL process used.

      Does HASL Oxidize?

      One of the main concerns with any PCB finish is oxidation, which can affect solderability and reliability. While HASL provides a protective solder layer that helps prevent oxidation, it is not entirely immune. Over time, especially in harsh environments, the solder can oxidize, leading to potential issues during assembly. However, proper storage and handling can minimize this risk, making HASL a reliable choice for many applications.

      How Thick Is the HASL Coating?

      The thickness of the HASL coating can vary depending on the process parameters and the type of solder used. Typically, the thickness ranges from 1 to 25 microns. This variability can be a drawback for applications requiring precise and consistent thickness, especially for fine-pitch components. However, for many general-purpose applications, the thickness provided by HASL is more than sufficient.

      What Is the Black Pad Syndrome?

      Black pad syndrome is a phenomenon associated with the ENIG finish, not HASL. It occurs when there is an issue with the nickel layer during the ENIG process, leading to poor solder joints and potential failures. The term “black pad” refers to the appearance of the affected nickel layer, which turns black due to oxidation and contamination. While this issue is unrelated to HASL, it’s important to note that HASL does not suffer from black pad syndrome, making it a more straightforward and reliable finish in this regard.

      When choosing between lead-free HASL and ENIG surface finishes for your PCB, it’s important to consider the specific needs of your project. For reliable and high-quality PCB manufacturer, consider working with Best Technology, a leader in the field. With our expertise and advanced technology, we ensure that your PCBs meet the highest standards of quality and performance. Whether you choose HASL or ENIG, we have the experience and capability to deliver the best results for your project.

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