Efficient Copper Foil PCB Manufacturer in China

Your Business Will Soar with PCBMay Copper Foil PCB

We don’t compromise quality for affordability with your Copper Foil PCB. Because we are PCBMay, we guarantee that your order pleases you.

Our authentic, world-class Copper Foil PCB ticks all the right boxes.

• Accurate utilization as PCB Copper Clad Laminate
• Precision-control application of electrolytic copper foil
• Adjust copper foil thickness according to specs
• Use High-strength or High TG copper foil if needed
• Capability to attach very thin copper foil for Flex PCB

You are a smart consumer, with many things in mind. The performance of your PCBs should not worry you. That is why you need to rely on a PCB manufacturer that has a long track record of satisfying customers. In our company, we are not happy if our customer is not happy.

When you contact us about your order, we immediately answer to get your details. You can ask us anything about Copper Foil PCB manufacture, design, or assembly. If you need help with Prototype PCB or Custom PCB, those can be facilitated with ease.

Do you need ultra-light Flex PCB? How about PCBs for miniaturized gadgets? PCBMay has it all. We even make Transparent PCBs and PCBs for advanced medical applications. This is how confident we are as PCB fabricators. Whatever PCB you wish to be constructed, our skilled engineers can handle it.

PCBMay is transparent and honest. We can furnish a weekly Work-in-Progress report for your orders if you need it. Since we are a global brand, we follow ISO: 9001 and ISO 14001. Expect no less from an international supplier of PCBs with thousands of customers.

So, what are you waiting for? Call us now!

Copper Foil PCB: The Ultimate FAQ Guide

Have you ever been amused thinking about the wiring and conduction in printed circuit boards?

Copper foil PCB ensures high-level current conduction in electronic applications. The reliable electric properties of copper foil make it an excellent solution for different problems in PCB.

PCBMay accommodates customized designs and quality assembly service for different printed circuit boards. Our copper foil circuit boards conform to all of your demands. This FAQ guide will inform you of the ins and outs of copper foils in PCB manufacturing. Let’s start.

What Is Copper Foil PCB?

A copper foil PCB is a highly functional circuit board. It contains copper foil in the external and internal layers. PCB copper foil is used as base thickness in the inner PCB layers. But an additional coating is applied to the outer copper foil during PCB manufacturing.

Usually, PCB copper foils have contact with the core of PCB base material. Again, you can find copper foils in multilayer circuit boards.

This PCB ensures a secured signal transmission in electronic appliances. Besides, there is no interruption due to the high conductivity of copper materials. It is compatible with different designs, materials, etc.

Copper foil is reputable for its low surface oxygen level. It provides outstanding performance while connected to various substrates. Moreover, this circuit board offers excellent durability because of the protective features of copper foils.

Various copper foil PCBs have extensive applications in many electronic projects. Such as

• Multilayer copper foil PCB (4, 8, 14 layers)
• Rigid copper foil PCB
• Flexible copper foil PCB
• Rigid-flex copper foil PCB

PCB copper foil sheets can make reliable bonds with insulating layers. That’s why this PCB remains functional in conditions. That means copper foil improves the overall performance of printed circuit boards.

Copper Foil For Printed Circuit Boards

What Types Of Materials Used In Copper Foil PCBs?

Copper foil PCBs are supportive of various high-quality materials. These PCB materials ensure electrical and mechanical properties in different electronic appliances. The most common materials of this circuit board include-

Substrate

PCB substrate is the glass-reinforced part of copper foil circuit boards. This is the base of the circuit board placed on plastic. This portion consists of composite epoxy materials and glasses.

These materials maintain necessary properties like transition temperature, decomposition temperature, dielectric strength, etc. You can also find 4 Grade fire retardant materials in this section of PCB copper foil.

Solder Mask

PCB solder mask presents the color of circuit laminate. Though color has no significant impact on PCB function, it can vary due to the client’s choice. Usually, copper foil circuit boards are green, but you can customize the color concerning your preference.

Silkscreen

Being a vital material of copper foil PCB, silkscreen holds different logos, numbers, etc. The silkscreen contains all texts of copper foil circuit boards. Engineers usually write some necessary information about the PCB functions on this part.

Materials Of Copper Foil PCB Laminate

Copper foils provide sufficient insulation in electronic devices that protect the PCB while handling high current loads. These PCB materials help the PCB copper foil function properly and maintain its features. You should ensure reliable component sourcing during PCB manufacturing. Otherwise, it will be a disaster for your projects.

What Are The Copper Foil PCB Features?

The most noteworthy features of a copper foil PCB are-

• A low surface oxygen rate.
• The purity of PCB copper foils is around 99.7%.
• High glass transition
• Low moisture absorption rate.
• The copper foil thicknesses for inner PCB layers are the same in the initial and final stages.
• Additional copper coating is required for outer layers.
• High decomposition rate.
• Pre-attachment ability with a metal core, FR4, etc.
• Compatible with multilayer stacks.
• Low CTE (Coefficient of Thermal Expansion)
• Lead-free compatible.

Notable Features Of Copper Foil PCB

Check this video about copper foils in PCB designs:

What Types Of Copper Foils Are Available In PCB Manufacturing?

Copper foil sheets play significant roles in the signal propagation of printed circuit boards. High-quality PCB copper foils offer worthwhile adhesion to dielectric layers that improve the efficiency of flexible and rigid-flex PCBs.

That’s why knowing about the copper foil types has great importance in PCB manufacturing. Usually, you can find two classes of copper foils in most circuit board assemblies. They are-

Rolled-Annealed Copper Foil

Rolled-Annealed (RA) copper foils are found in Yellow color. These copper foils offer almost the same roughness on both surfaces. Their surface roughness is not very high (0.35 microns). That’s why RA PCB copper foils are widely used in high-frequency PCB applications.

The most significant properties of these copper sheets include-

• High resistance against the cracking due to thermal stresses.
• Commendable elastic elongation.
• Reliable etching facilities for high-frequency and RF circuit boards.

So, you can depend on RA copper foil sheets at extreme thermal pressures. Besides, their elasticity improved the stability of electronic devices based on a copper foil PCB.

Electrodeposited Copper Foil

Being a Reddish sheet, electrodeposited (ED)think copper foil provides superb robustness in electronic appliances. If you are worried about the mechanical stability of your devices, you should think of ED copper foils.

Its significant features are-

• The surface roughness is very high (0.40 micron) compared to RA copper foils.
• High mechanical rigidity.
• Thermal cycling is high-speed. That’s why conductor cracking is widespread in the case of ED copper foils.
• Excellent tensile strength.
• Improved elongation due to elasticity.
• High loss of conductors because of increased surface roughness.
• The insertion loss is also very high.

It is essential to be aware of both PCB copper foils to optimize the circuit board designs. The surface roughness, thermal cycling, elasticity, etc are vital factors in choosing a suitable copper foil. In the case of any difficulty, consult a trustworthy manufacturer to take care of Copper foils in PCBs.

Flexible Copper Foil PCB

What Is A Copper Foil Used For In PCB?

A copper foil is used for printed circuit boards because of multiple reasons. The most significant causes are-

• Impressive electrical conduction of copper is the foremost cause of using copper foils in PCB.
• Coper foils have high thermal conduction in electronic applications.
• The mechanical stability of PCB copper foils is excellent.
• It offers outstanding insulation in PCB applications.
• Copper foil circuit boards last for a significant time due to the superb functionality of copper foils.
• PCB copper foil price is affordable.
• PCB copper foil repair service is not very complicated and expensive.

Uses Of Copper Foil PCB

How Do You Repair Broken Copper Foil PCB Traces?

Usually, copper foil PCB traces get broken due to high electrical and mechanical pressures. The traditional way for copper foil PCB repair is bypassing an electrical wire around the broken PCB trace. But it is not a reliable and convenient process.

You should use a conductive pen in this case. Usually, conductive pens hold silver and nickel. These materials create a polymer that offers excellent flexibility in redrawing the broken trace on copper foil PCB.

There are some techniques of using conductive pens on a trace. Such as

• First, scrape away an exposed zone of the main trace.
• Clean this area by using isopropyl alcohol. You can also apply a remover pen for this purpose.
• Then, apply the conductive ink through the pen. Don’t forget to shake the pen properly before using it.
• Use an overcoat pen when you repair the broken trace.

Copper Foil Circuit Board Repair

Check this video to know more about the copper foil PCB trace repair:

What Is The PCB Copper Foil Thickness?

PCB copper foil thickness ensures high current conduction during PCB manufacturing. Besides, copper foil thickness affects other features of printed circuit boards.

It varies concerning the board size, requirement of current conduction, number of layers, etc. The most used copper foil thicknesses are 18 micrometers and 35 micrometers.

A copper foil circuit board allows customization in the case of thickness. You can use 2 oz or 3 oz thick copper foils if you require a high flow of charges during the PCB operation.

Thicker copper foils improve the current conduction capacity in the circuit board. But the printed circuit boards having thinner copper foils are easy to etch and less expensive.

Besides, it is challenging to ensure dielectric properties in thick copper foils. So, you have to make a balance while choosing a suitable copper foil thickness for your PCB.

PCB Copper Foil Thickness

How To Remove Conformal Coatings While Repairing A Copper Foil PCB?

It is very tough to remove conformal coating safely while repairing a copper foil PCB. Its process varies concerning the types of conformal coatings you use in PCB.

You can apply three different techniques for the most conformal coatings like Acrylic, Silicon, Epoxy Resin, Ultra-thin coatings, etc. Let’s see.

Hard Coatings

Parylene and epoxy resin coatings are very hard. These conformal coatings have great tolerance to chemical and mechanical forces. That’s why you can’t remove these coatings by applying chemicals. Besides, heat causes damage to the copper foils during the repair.

Micro-abrasive blasting is the most effective removal of Parylene and Epoxy resin coatings. In this case, a device blows the harsh particles from the coated surface.

Using micro-abrasive blasting, you need to follow the necessary instructions to achieve the best outcome. Such as

• Cover the repair zone to avoid unwanted removal of necessary components.
• Select the abrasive medium concerning your PCB components.

Ultra-thin Coatings

Ultra-thin conformal coatings are invisible to a large extent. So, you don’t need to think about their removal.

You can find ultra-thin coatings in advanced electronic devices. Their easy removal while repairing makes them compatible with consumer electronic products.

Soft Coatings

Urethane, Acrylic, Silicon coatings are comparatively softer than Epoxy resin or Parylene coatings. You don’t need to apply any abrasive medium to remove these conformal coatings.

You can rely on the traditional burning method in this case. But some considerations can save you from additional difficulties after removing conformal coatings.

• Ensure sufficient ventilation while removing the conformal coatings.
• A through-burning leaves some hard edges in copper foil circuit board repair services. So, don’t forget to clean these edges before applying the subsequent coating.
• You should choose a coating remover that offers less toxicity. Some solvents like toluene and xylene can dissolve conformal coatings. But these materials can affect the circuit board components connected to the repair area. So, you can use a coating remover pen to avoid such unwanted incidents.
• Wait for some moments after rubbing and wiping the pen on the resin. Usually, silicone coatings take more time than acrylic coatings.
• Wear your protective equipment.

Conformal Coating Removal From Copper Foil PCB

What Are Copper Foil PCB Limitations?

Copper foil PCBs have some limitations, along with a lot of positive features. The most notable disadvantages of these circuit boards include-

• Sometimes, a copper foil PCB malfunctions in high-frequency applications due to rough surfaces. Achieving smooth copper foils for PCB manufacturing is a highly challenging task.
• This circuit board requires high-quality maintenance. That means the maintenance of this PCB cost is a little bit high.
• Ensuring desired TG value is not very easy in this case. That’s why its ability to handle thermal pressures is not impressive in some events.

These limitations are minimizable. You just need to select a trustworthy copper foil PCB manufacturer to avoid such adverse effects.

Limitations Of Copper Foil Circuit Board

10. How Does Copper Foil PCB Roughness Affect Impedance And Signal Transmission Loss?

Copper foil roughness significantly impacts impedance control and signal transmission loss in PCB. Usually, PCB impedance in the transmission line depends on four parameters. These parameters include-

• DC Resistance
• Loop Inductance
• Line Capacitance
• Conductance of Substrate

Coffer foil roughness affects all of these parameters. When the roughness of copper is present, signal transmission loss becomes prominent at a specific frequency range. That’s why you can’t get optimum output in high-frequency signal transmission systems.

Besides, copper foil roughness increases the skin effect. It becomes minimum in the case of smooth copper surfaces. The skin effect hampers high-density and high-frequency data propagation to a large extent.

The other effect of copper foil roughness is dispersion. PCB dispersion causes considerable deviation from the controlled impedance. So, you must consider the roughness in copper foil sheets while manufacturing the circuit boards.

Copper Foil Surface Roughness

Is Copper Foil Used In Flexible PCB Manufacturing?

Yes. Copper foil is highly applicable in flexible PCB manufacturing. PCB copper foil provides excellent insulation in FPCs (Flexible Printed Circuits). The insulating properties are necessary to maintain dielectric strength and stretchability in flexible circuits.

Besides, the slim profiles of PCB copper foils are supportive of flexible and rigid-flex PCBs. Usually, copper foils ensure high current carrying capacity in the circuit boards. The PCB copper foil thickness is worthwhile for flexible designs. So, you can use PCB copper foils in flex PCB manufacturing without any hesitation.

Copper Foil In Flexible Circuit Boards

Do Copper Foil PCBs Support Multilayer Designs?

Copper foil PCBs support multilayer designs to a great extent. Their assembling and operating principles are compatible with high layer counts. Usually, a well-structured multilayer stackup requires low dielectric constants in different layers.

Copper foil PCBs consist of FR4 and CEM-3 as base materials. These PCB materials fulfill all requirements for multilayer stacks. Besides, various copper thickness, SMT component mounting, etc are necessary to optimize multilayer designs.

You can apply surface mound devices during the assembly. So, these circuit boards’ soldering, thermal management, and component placement are highly reliable.

Copper Foil In Multilayer Stackup

What Is Electrolytic Copper Foil PCB?

Copper materials promote the conductivity of printed circuit boards. The electrolytic copper foil PCB is a practical circuit board containing rolled copper of around 80m thickness.

Here, the acid dissolves a high-grade copper foil to make it electrolytic. After proper annealing and rolling, you can get electrodeposited copper.

This electrodeposited copper is placed in a rolling drum. Then, manufacturers roll it multiple times. Usually, electrolytic copper foil circuit boards are reputable for their high tensile strength. Besides, their elongation capability is also impressive.

You can use these circuit boards consisting of electrolytic copper foil in flexible and rigid-flex electronic applications. Besides, these PCBs allow you to customize designs as per your demands to a great extent.

Electrolytic Copper Foil For PCB Manufacturing

What Are The Testings Of A Copper Foil PCB?

You can test the functionalities of copper foil PCBs in many ways. There are different visual and automated inspections available to test PCB copper foils. Now, we are going to let you know about these testings. Let’s have a look.

Automated Optical Inspection

The AOI (Automated Optical Inspection) involves comparing 2D and 3D images of your circuit board with an ideal PCB design. Here, an AOI machine, consisting of a high-class camera, takes photographs of PCB copper foil sheets from different angles.

Then, the inspector analyses these images through an automated system. If your PCB doesn’t match the ideal design to a certain extent, it is considered defective.

This test is very fast. It delivers reliable results on catastrophic failures and quality defects of PCB. It is not highly applicable in small-scale PCB manufacturing due to its high expense. So, you can rely on this inspection for high-volume copper foil circuit board testings.

Automated X-ray Inspection

This test detects the dimensional defects of copper foil circuit boards. Here, an inspector applies an X-ray, a highly penetrable ray. Then, this ray effectively finds faults in solder joints, drilled holes, press-fit, etc.

But this inspection is not very popular to detect missing components, faulty wire connections, current ratings, etc.

Flying Probe Test

The FPT (Flying Probe Test) is optimal for testing a wide range of high-density copper foil PCBs. Various electrical probes are involved and set at the X, Y, and Z axes in these cases.

The inspector supplies a signal during the test and makes contact between the circuit board and these probes. Then, you can find out electrical features like the current, voltage, power ratings, wire connections, etc.

There is no need for extra fixtures. That’s why the FPT is a low-cost inspection for copper foil circuit boards. Besides, you can control the pressure while the probes touch the PCB surface. That means this test enables you to leave the PCB free from any mark.

Except for these inspections, you can conduct environmental tests, functional tests, tensile strength tests for this PCB. Then, you can be sure of your circuit board’s functional properties and durability.

PCB Copper Foil Testing

What is Surface Conductor Thickness In Copper Foil PCB?

The surface conductor thickness has excellent importance in Copper foil PCB manufacturing. This feature should be compatible with the requirements of the IPC standards.

The minimum surface conductor thickness is the sum of copper foil and copper plating. It depends on vital factors, like copper weight, processing allowance reduction, etc.

In the case of 1 oz copper of Class 1 and 2, the minimum surface conductor thickness is around 35 micrometers after processing. Here,

Minimum copper foil= 18 micrometers

Minimum copper plating= 35micrometers

Variable processing allowance reduction= 3 micrometers

Again, for 4 oz copper,

Minimum copper foil= 123.5 micrometers

Minimum copper plating= 143.5 micrometers

Variable processing allowance reduction= 4 micrometers

So, the minimum surface conductor thickness is around 139.5 micrometers after processing.

Besides, the minimum surface conductor thickness for internal layers of 1 oz copper is around 24.9 micrometers. This value varies concerning the copper thickness in PCB copper foils.

How Do You Choose A Trustworthy Copper Foil PCB Manufacturer?

Copper foil PCB manufacturing requires close attention to achieve optimum results. That’s why choosing a trustworthy copper foil circuit board manufacturer is crucial. But how do you be sure about the reliability of this PCB?

You need to consider the following issues that help you make a perfect choice.

• The ability to use high-quality raw materials for PCB assembly.
• Use of high TG copper foils during manufacturing.
• Skilled technicians to utilize copper-clad laminate of printed circuit boards.
• The capability of applying thin copper foils for manufacturing flexible PCBs.
• Long experience in adjusting copper foil thickness based on the client’s requirement.
• Precision control and testing facilities.
• Customization facilities.
• Reliable sourcing for PCB materials.
• Affordable product costs.
• Certifications from IPC and RoHS.
• Smart customer and sales service.

We offer IPC class 2 and 3 copper foil circuit boards at reasonable costs. Besides, we have a firm reputation for client satisfaction. Inquire us to boost your business based on PCB copper foils.

PCB Copper Foil Manufacturing

Conclusion

Copper foil PCB provides a smooth continuation of electron flow in versatile designs. A high-quality integration with insulating layers makes PCB copper foils more effective. Due to its features, you can be free from tension about EMI, signal flow, etc.

If you want to optimize copper foils in your PCB projects, PCBMay is the best option for you. We deliver high-class manufacturing services for different copper foil flexible and high TG circuit boards. Contact us to improve your PCB experience.