Venture: Your Best Thick Copper PCB Supplier in China

As a professional supplier and manufacturer, Venture is able to produce high-quality Thick Copper PCB that will suit your needs. We are an expert when it comes to manufacturing different types of Thick Copper PCB. Our Thick Copper PCB includes:

• 1 oz copper PCB
• 2 oz copper PCB
• 3 oz copper PCB
• 4 oz copper PCB
• 6 oz copper PCB
• 10 oz copper PCB
• 20 oz copper PCB

Venture Thick Copper PCB can provide you a maximum possibility to establish complex switches even in a limited space to combine with circuitry, especially for high current levels.

Mainly, Venture thick copper PCB is commonly used for power electronic devices and central power systems. Our thick copper PCB can conduct a higher current while decreasing the product size.

Our Thick Copper PCB is also suitable for high current applications. These are also perfect for thermal distribution for better thermal management. It is also best for heat dissipation to provide components with huge power loss.

If you want to request a thick copper PCB and have detailed specifications in mind, the Venture Electronics Design Team is much willing to help you.

We also have well-trained Layout Engineers to help you match your design drawings and schematic files. We are committed to enhancing prototyping by the production process to quote and delivery.

Whether you are a maker, system integrator, product designer, or electrical engineer looking for a cost-effective Thick Copper PCB, Venture Electronics is your best manufacturer in China!

We have more than 10 years of being a turnkey thick Copper PCB solution provider in China. As a professional manufacturer, we can provide unmatched customer services.

Feel free to contact us if you have more inquiries about our Thick Copper PCB!

Thick Copper PCB: The Ultimate FAQ Guide

This guide will take you through the basic and advanced concepts about thick copper PCBs.

So, before you fabricate, or import thick copper printed circuit boards from China, read this guide.

It will help you become an expert in the thick copper PCB industry.

Let’s dive right in:

What is the PCB?

PCB stands for a printed circuit board.

A printed circuit board accommodates electric components on a single platform while providing structural support and electrical connection to said components.

The PCB decreased the complexity of wire connections and increased the reliability of the established circuits.

 Thick copper PCB

This allowed for the creation of large circuits with the ability to connect multiple electronic components with different functions.

The PCB eliminates wire complexity by connecting components internally through etched conductive lines/paths.

You will find PCBs in electrical equipment used in various:

• Industries electrical appliances
• Medical equipment
• Lighting features
• Industrial machines
• Automotive industry

What is the Thick Copper PCB?

The thick copper PCB is a PCB that contains more than three ounces per square foot of copper material and used in carrying high current loads.

You find that the thickness of the copper material used in this PCB type is between 105 to 400 µm.

The thick copper PCB also can sustain high-temperature dissipation while providing firmer connections.

Also, the thermal management property enables the thick copper PCB to alleviate thermal stress.

Thick copper PCB

What are the Advantages of using Thick Copper PCB?

You find thick copper PCB with the following desirable characteristics.

This allows the thick copper PCB use in certain unique applications.

· Thick Copper PCB can Conduct Large Current Amounts

This feature enables the thick copper PCB to be used in equipment or machinery with large current capabilities such as heavy industrial machinery.

· Thick Copper PCB has an Impressive Distribution of Dissipated Heat

With this feature, the thick copper PCB is highly efficient in its management of thermal energy enabling reliability of performance.

You find the thick copper PCB can be used in elevated temperature conditions without slack in performance levels.

Additionally, this feature enables the use of the thick copper PCB in high power machinery and equipment.

Such machines are characterized by their large heat production which can be well managed by the thick copper PCB.

You also find the admirable heat distribution allows the thick copper PCB to double up as some form of a heat sink.

This allows a cheaper and efficient way of dissipating heat.

Cost is reduced by eliminating the need to attach an actual heat sink construction to the PCB.

· Thick Copper PCB has Admirable Mechanical Strength

You find the printed circuit board offers foundational support for the components contained within it.

The PCB, therefore, has to offer a good support structure.

The thick copper PCB provides good mechanical support for the components making them firm and functionally dependable.

· Thick Copper PCB is Highly Compatible with other Materials

When making a printed circuit board, other materials may be used in the fabrication process.

Using different materials may result in compatibility issues which bring about failure in select components.

Using a thick copper PCB minimizes instances of such failures due to their high material compatibility.

· Simplifies Connection

Thick copper PCB does away with the use of wires as connection paths for the printed circuit board.

This simplifies the circuit board infrastructure allowing easy identification of parts and board navigation.

· Reduces the need for Multiple Layers

The thick copper PCB allows the use of several ounces of copper in a single layer.

This lessens the distribution of circuitry across multiple layers.

What are the Design Elements of Thick Copper PCB?

 Thick copper PCB design

A thick copper PCB is used as the most efficient alternative of printed circuit boards when it comes to managing heat generated in the process.

This is because the thick copper PCB can accommodate the transfer of large currents while also safely dissipating excess heat.

Consequently, you find that the design of the thick copper PCB has to deliberate on the needs of the applied system.

As a result, the following design elements are to be emphasized.

• The required dimensions for the PCB.
• The spacing of components on the PCB
• The component types to be accommodated on the PCB.

How do you Fabricate Thick Copper PCB?

 Thick copper printed circuit board

A printed circuit board of thick copper is fabricated by applying copper layers into a substrate.

Since copper is electrically conductive, it provides a conductive path for electric transfer between components.

Depending on the application, the design elements of size, spacing, and component type are considered before the fabrication process begins.

There are two approaches to fabricating a printed circuit board with thick copper:

1. Etching

Etching is a process where a pattern is cut into a surface before the pattern itself being highlighted.

In this instance, the design for the conductive path is patterned onto the substrate.

Molten copper is then filled up into the cut pattern.

2. Plating

Plating describes the process of depositing a surface of some material with another.

This process is also applied in the fabrication of thick copper PCB.

In this case, the copper is deposited on to a substrate in line with the conductive path design.

Both the mentioned processes above are performed on the substrate by using sidewalls and also holes utilizing printing screens.

What is Undercutting in Thick Copper PCB Fabrication?

When the conductive pattern for the thick copper being engraved via etching is made, it is called undercutting.

This process adjusts downward the width of the circuit path while accentuating its thickness.

Through undercutting, the path’s obverse view takes more of a trapezoidal appearance than being squared.

Undercut in PCB

What are the Specifications of the Thick Copper PCB?

The following are some important specifications useful in advising your selection of the thick copper PCB.

These specifications are imperative with the design elements and application needs.

They include:

· Thickness of the Copper on the Printed Circuit Board

You find that to qualify as a thick copper PCB, the thickness has to be between 105 to 400 µm.

Beyond this thickness requirement, your application needs will determine how thick of a PCB you will require.

Thickness is directly related to the current-carrying ability.

· Width of the Copper

While the thickness is a vertical dimension aspect, the width provides its horizontal aspect.

The amount of current to be conducted will also determine the width of the thick copper.

Large currents will require relatively larger widths.

· Thick Copper PCB’s Current Handling Capability

The current value to be conducted by the thick copper PCB is essential in determining your selection.

Applications requiring larger current needs will require thick copper PCBs of larger thickness.

· Tolerance of the Thick Copper

The tolerance value of the thick copper in the thick copper PCB will depend on the fabrication method used and the copper thickness.

Tolerance values will also be affected by the application conditions.

· Number of Layers

Thick copper PCBs can come in multiple layers.

Once again you need to consider the area of use of the thick copper PCB.

With more layers, so are the ounces of thick copper used per square feet.

· Voltage and Power Requirements

Voltage, power, and current are related through Ohm’s law.

You find that thick copper PCBs are used for large currents transfer.

It follows that voltage and power requirements need to be low for performance efficiency.

· Surface Finish used

The surface finish applied for the thick copper PCB is dependent on the application of the PCB.

Different applications will require different surface finalities.

For internal usage, polished finishes are common.

Where are Thick Copper PCBs used?

You find the thick copper PCB has multiple usages across various industries.

Current transfer and thermal management are the biggest strong points of the thick copper PCB.

You, therefore, find the two aspects providing the guiding tenets of usage.

The thick copper PCB finds application in the automotive industry, the computer industry, and the household and services appliances industry.

Some specific applications include:

• Use in signaling systems and torque controls
• Use in converters such as power converters and traction converters for railways, and solar converters.
• Power systems such as line monitors and reactors
• Power regulators and rectifiers
• Use in grid switching and backup
• Nuclear power and hydro-electric plant use thick copper PCBs.
• Charging systems for electric vehicles and uninterrupted power supplies rely on thick copper PCBs.
• Thick copper PCBs also find use in military and civil applications such as weapon control and radio detection and ranging.

How are Components Mounted on the Thick Copper PCB?

Printed circuit boards are used to provide a simple, convenient, and reliable path for electrical conductance between components.

These components have to be attached to the thick copper trace on the board.

The following approaches are used to mount components on the thick copper PCB.

·  Through-hole Mounting Technology

The through-hole thick copper PCB has holes emblazoned on it through which components’ leads are fitted.

The leads are then attached to the landing pads on the PCB’s reverse by a process such as soldering.

This provides an electrical connection for the components.

The through-hole thick copper PCB design provides a firmer foundation for the accommodated components.

This ensures the stability of the electrical components and as a result, dependable performance as intended.

For a through-hole thick copper PCB, the cost of fabrication is higher.

This is because the holes are made by drilling which requires additional equipment and time resources.

Additionally, it is a process that commands high precision.

The cost of drilling is directly related to the thickness of the thick copper.

Therefore, thick copper PCBs of through-hole identification with larger thickness will cost more than those with smaller thickness.

· Surface-mounted Technology

Thick copper PCBs that are surface mounted typically indulge in the use of tiny components.

Usually, these components lack leads or have very small ones limited to the size restrictions of through-hole mountings.

With the surface-mounted technology, the components are attached to landing pads or contacts on the PCB.

Surface mount technology

The pads are placed on the conductive path of the thick copper allowing for the electrical connection of the components.

The components are usually attached to the pads through soldering.

This tends to provide a more permanent connection between the components and the PCB.

What are the Parts of Thick Copper PCB?

You will find the thick copper PCB with the following different parts.

· Contact Pads/ Holes

Depending on the type of thick copper PCB, you will either find holes or pads.

Through-hole thick copper PCBs have holes while surface mounted PCBs have pads.

The holes and pads are used to provide an electrical attachment to the PCB’s conductive path.

Additionally, you find that holes and pads are useful in providing structural support to the components assembled on the PCB.

Holes are used for components with leads that are long enough.

Pads are specifically used for small electrical components with small leads or with the leads absent.

· Conductive Trace

Rather than use wires, the thick copper PCB utilizes a pattern made of copper to provide electrical conductivity.

This copper pattern is referred to as a conductive trace or simply as a trace.

The trace provides an electrical connection for the connected components on the PCB.

· Layers

The thick copper PCB is embedded in a layer formation of the overall printed circuit board construction.

Just like the thickness of the thick copper will vary according to the application, so will the number of layers.

Additionally, it follows that the more the layers in a thick copper PCB, the higher the cost of constructing the PCB.

The number of layers is also subject to the requirements of space allowed for the PCB.

For applications requiring large current values and with sophisticated circuit developments, multiple layers will be necessary.

Furthermore, thick copper PCBs with larger thickness sizes accommodate more than a single layer.

The use of multiple layers requires the provision of an electrical path between the layers.

Providing such a path allows for the fixation of several components on the PCB.

There can be a top layer and a bottom layer.

You find the electrical components placed on the top layer of a thick copper PCB.

The bottom layer is characteristic of the through-hole thick copper PCB.

It provides a surface for attachment to the leads of the electrical components on the top layer.

The top layer, the solder mask, is commonly colored green with solder joints used in connecting the components to the trace.

An insulating layer is provided to isolate electrical components from each other.

This prevents unintended electrical contact between components.

What Dielectric Materials are used on the Thick Copper PCB?

The thick copper is usually embedded within a dielectric material that could be made to some degree of flexibility and rigidness.

Epoxies derived from glass substrates and materials composed of mixed elements are commonly used as a dielectric.

These materials include:

i. Fire Retardant (FR)

The fire retardant is a class of material based on glass, epoxy, paper, and phenol compounds.

We have different variants of fire retardant materials including FR 1, FR 2, and FR 4.

The FR 1 and FR 2 are derived from paper compounds and phenol substances.

They are uncommon for the thick copper PCB but are present in other PCB types such as the single layer.

FR 1 Material

You can find the FR 1 and FR 2 with options of water-resistant and free of halogen compounds.

The temperature of the glass transition provides the major difference between FR 1 and FR 2.

You find the FR 1 having a higher temperature value than the FR 2.

The FR 4 is glass-based with elements of epoxy.

This material is rigid and mechanically stable finding the most common use among fire-retardant materials.

It also has a high glass transition temperature.

The FR 4 is free of halogen traces and can be used in technological endeavors where lead is absent.

Additionally, you find the FR 4 material is most affordable of the fire-retardant materials.

ii. Composite Epoxy Material (CEM)

Composite epoxy materials are derived from glass, phenol, and epoxy compounds.

You find two variants of composite epoxy material; CEM 1 and CEM 2.

CEM 1 Material

CEM 1 is commonly used for surface mounted PCBs whereas CEM 3 can be used as well for through-hole PCBs.

The CEM 3 is usually provided in white and can be used instead of the FR 4 in thick copper PCBs.

However, it has the limitations of being costlier with lower mechanical stability.

iii. Prepreg Material

Prepeg material for PCB

Prepreg is a wordplay on pre-impregnated which explains the material composition of this compound.

The prepreg consists of fiberglass material that has been infused with resin material.

Before impregnating the resin with the fiberglass, it is dried to allow it to have a sticky flow when melted.

The molten resin is then infused with the fiberglass.

Prepeg is made with a layer that exhibits strength property akin to the FR 4.

You find the prepreg material is classified in line with the resin amount contained therein.

Therefore, you will find prepreg material with high resin content, standard resin content, or medium resin content.

The resin content in the prepreg material helps determine its use in a thick copper PCB of defined thickness, structure, or impedance.

Furthermore, prepreg material has a high transition temperature of glass and free of halogen compound.

How can you Design Thick Copper PCB?

Yes, you can.

Designing a printed circuit board has been made possible with the use of computer-aided software available in the market.

These PCB design softwares are user-friendly finding use in both academic halls and industrial labs.

They allow you to elaborately develop customized PCB designs.

These softwares can be OS-based or web-based. You can use the software to design the circuit diagrams and edit them schematically.

Some software also provides simulation while allowing you to import and export the desired features to your PCB layout.

Additionally, some allow 3D design visualization while also letting you incorporate all circuit components in your design.

All this can be done by anyone across the universe with the softwares supporting different languages.

What Design Approaches are Available in Thick Copper PCB?

Designing is coming up with a plan or approach on how to successfully execute an objective.

Concerning the thick copper PCB, designing entails approaches to create a functionally stable and reliable PCB.

The following approaches to design are considered.

PCB Layout design

· Designing for Manufacture

Design for manufacture elaborates on the strategies to be used in the making of the PCB.

It is while designing for manufacture that the use of robots is put down.

Additionally, materials for use in the different processes are determined at this point.

Designing for manufacture seeks to increase productivity while reducing costs.

Strategies for cost reduction can be using fewer layers, less heavy copper, and having a low component count.

Efforts can also be made to increase the space between components.

Considerations for system compatibility and standardization are also discussed at the design for manufacture.

Standardization of hardware allows them to fit in other systems.

The order of components on the PCB is also provided for while designing for manufacture.

Designing for Testability

While designing the thick copper PCB, consideration has to be provided to allow for feasible testing procedures.

This enables the creation of a PCB that can be tested with a variant of methods to establish its performance reliability.

For example, if components are subject to test procedures, then the design ensures easy access for the component leads.

Additionally, when components need to individually tested, systems are put in place to allow for isolation within the design.

Design for testability is a useful approach that allows for increased efficiency levels and product reliability.

Designing for Ease of Repair

For any given product, it is expected at some stage to fall into damage or unexpected fault.

When this happens rather than replace the product, it is prudent to carry out repairs.

However, this can only be feasible if the product was designed to allow repair works to be carried out.

Designing a product for repair allows you to rehabilitate a product upon failure after purchase.

For the thick copper PCB, designing for repair can include interventions such as providing extra slots for easily damaged components.

This allows you to replace them.

Additionally, the design for ease of repair can provide expansion slots for improving the system for performance.

You can also find increased space between components on the circuit board for easy maneuverability.

Can a Thick Copper PCB be used as a Motherboard?

Yes, it can.

A motherboard is a name given to the major circuit board for an elaborate system such as a computer.

Depending on the application, a motherboard can have components built on it and others connected to it.

A thick copper PCB is used in applications requiring large current transferals and efficient thermal management.

Many supercomputers and server systems consume such large currents requiring proper thermal management.

In such systems, the main circuit boards can be built on thick copper PCBs.

What Construction can Thick Copper PCB take?

You find there are three different forms of construction of the thick copper PCB.

The construction is dependent on the number of components and the mounting method used.

· Single-sided Boards

With this board type, all the components are on one side.

You find single-sided construction in applications where the circuit components are few.

Additionally, many surface-mounted components are typically placed on a single side of the substrate.

· Double-sided Board

This board type is useful when there is a high component count that makes placing them all on one side impossible.

With this construction, some components are placed on one side of the board while the others are fitted in the reverse.

Electrical connections between the two sides of the board are provided via drilled holes.

The holes are made conductive or attached with conductive paths to connect the two surfaces.

This ensures no interruption in the intended circuit.

· Multi-layered Board

This construction type has the substrate divided into layers.

These layers consist of printed thick copper circuits and insulation layers.

The arrangement is such that the circuits are separated from each other by the insulating layers.

Like the double-sided board, the layers in the multi-layered board are connected.

Holes are drilled through the substrate layers and conductive paths created.

The benefit of this configuration is the simplification of the circuitry and accommodation of several components.

How do you Determine Appropriate Thickness for a Thick Copper PCB?

Thick copper PCB

When deciding the thickness of your thick copper PCB, you need to consider the current amount to be conducted.

This should be able to reflect how much a thermal energy change the PCB can bear.

Furthermore, an inquiry into the level of structural support that can be provided by the selected thickness is important.

This will also be influenced by the size of the drilled holes and the multilayer connected sustained.

You will also find the material choice for the thick copper PCB influential in determining copper thickness.

Some materials possess strong structural stability at elevated temperatures.

This will require much less thickness than those that easily succumb to such extremities.

Can an Integrated Circuit be Placed on a Thick Copper PCB?

Yes, it can.

An integrated circuit is composed of miniaturized electrical components that are built-up on a semiconductor substrate.

These components are connected in a way to achieve a certain defined function.

Integrated circuit chips are fitted with leads allowing them to be placed on a printed circuit board.

Integrated circuit chips can be surface mounted or connected through the hole on a thick copper PCB.

What is the Difference between the Thick Copper PCB and the Integrated Circuit?

 5 Oz PCB

You find that the thick copper printed circuit board is a panel providing conductive paths for connected components.

It simplified the connection process by eliminating the use of wires.

Wires provided a complex path and their entanglement made their management difficult.

The integrated circuit serves to improve functional aspects of processes by integrating relevant electronic components into a single network.

This is done by growing the components in a die and connecting them.

Therefore, you find that integrated circuits have miniaturized components built-up on them.

Contrarily, the thick copper printed circuit board lacks grown components instead of providing for a connecting mechanism to the desired components.

What are Laminates on Thick Copper PCBs?

Laminates are used to firm up the thick copper PCB layers.

They are useful in influencing the structural property of the thick copper PCB.

Laminates derive their properties from the materials used in making them.

Laminates are made by subjecting pieces of cloth or paper with resin to elevated temperatures and pressure conditions.

This process is undertaken to derive a singular piece with an even thickness.

Dielectric properties can be adjusted by varying the materials used.

Laminates should be resistant to fire to some level, have tensile and shear strength aspects.

Additionally, they should have a low loss factor concerning its dielectric and thermal properties.

Common materials used in the making of laminates include epoxy, polyimide, Teflon, copper cladding, and FR-4.

How is the Substrate for the Thick Copper PCB made?

You find the following steps in the making of the substrate for a thick copper PCB.

These steps are true for prepreg material.

• A glass-epoxy compound of a woven structure is infused with resin. This is done either by spraying the resin onto the fiber roll or dipping.
• The resulting fiber-resin combination is taken through a rolling chamber where the appropriate thickness is determined. Here, the superfluous resin is also removed.
• The rolled material compound of the required thickness is heated in an oven in a process called semi-curing. The semi-cured composite is thereafter cut into panels.
• The panels are arranged vertically with layers of copper foil sandwiched in between. This is done according to the number of desired layers.
• The resultant layer of alternating substrate panel and copper foil is pressed at a temperature of over 150 °C. This is done for about an hour at a high pressure of over 1400 pounds per square inch.

The step above forms the final curing process for the resin providing a tight bond between the substrate and the copper layer.

What are some of the Substrate Parameters for Thick Copper PCB?

Thick copper PCB

The substrate for the thick copper PCBs is usually material compounds with dielectric properties.

These compounds typically contain a reinforced medium usually epoxy and glass fibers, phenol, or paper.

The common substrate parameters are usually derivatives of their thermo-mechanical or electrical properties.

Some parameters are as follows:

· Glass Transition Temperature

The glass transition is the process where glass fiber particles turn to a molten state when the temperature is increased.

This transition is reversible.

The temperature range at which point this occurs is called the glass transition temperature.

For the substrate composite knowing the glass transition temperature is important since it could result in an expansion and overload of components.

The glass transition temperature of the substrate should be high to prevent transition when under temperature extremities.

· Tensile Strength

The tensile strength of a material describes the highest stress value that a material can be subjected to through stretching before breaking.

Material with low tensile strength is said to be brittle while those with higher strength values are ductile.

The substrate material should have good tensile strength.

Also, the substrate material can be tested for its tensile strength by subjecting it to pulling forces.

· Shear Strength

The shear strength of a material refers to its ability to withstand an exerted sheer force.

A shear force is a force that draws a reaction along a parallel plane when the material fails.

The failure is usually in a descending approach from the point of application of shear load.

Substrate material offers mechanical support to components.

These components exert different load values at their precise location points.

Substrates may fail when components exert a force exceeding their sheer value.

· Thermal Expansion

Thermal expansion is the property of a material that results in a change in its structure when subjected to different temperature values.

This change could be in its shape through expansion, as well as size and area.

Thermal expansion can be expressed as a coefficient when the strain resulting from the expansion is determined over a defined temperature change.

Substrate materials need low coefficients of thermal expansion to allow performance consistency over a wider temperature range.

Additionally, the components on board should have a coefficient of expansion equal to or close to the substrates.

This ensures uniform responses to temperature changes.

·  Dielectric Constant

The dielectric constant of the substrate is determined by its material composition.

The dielectric constant is a factor that describes the particle charge effect in a material relative to a vacuum.

You find the dielectric constant decreases when the frequency is increased.

Therefore, the substrate choice in making thick copper PCB will depend on its application.

· Loss Tangent

Loss tangent is another substrate parameter that is influenced by frequency.

Loss tangent describes the rate of absorption of electromagnetic energy emitted by conductors, in this case, the substrate.

Absorbing this energy interferes with the board structure and when used with sensitive components, their function as well.

Materials with low loss tangent are admirable but come at a premium.

· Dielectric Breakdown Voltage

The breakdown voltage for a dielectric describes the highest gradient voltage value that a dielectric can withstand before breakdown occurs.

For a substrate, this point results in the ability of the substrate to allow electrical energy transfer.

Substrates carry the thick copper circuit path on PCBs allowing connection of components.

A breakdown can result in massive component failure and circuit interruptions.

Materials used for substrates should, therefore, have a high dielectric breakdown voltage value.

· Tracking Resistance

The tracking resistance of a substrate is determined by the material used.

It highlights the resistance to elevated voltage presence on the circuit board by the material.

A high tracking resistance is commendable to prevent charge disruptions on the board.

· Moisture Absorption

Moisture content increases with highly humid environments or the presence of water particles.

Also, the moisture absorption is the uptake of this water content by the substrate.

The rate of absorption will be determined by the materials used in the substrate.

For substrate compounds with epoxy, teflon, and glass, the moisture absorption rate is low.

Compounds with polyimides, paper, and cyanate ester are highly absorbent.

Therefore, careful selection of material based on the application will help control absorption.

Increased moisture content in the substrate will affect other parameters.

Dielectric parameters, the tracking resistance, and voltage of breakdown are some of the parameters that can be affected.

Moisture absorption is less prevalent in dry areas.

Measures such as fanning and heat distribution can work to mitigate the moisture levels of the substrate.

How are Holes Drilled on the Substrate of Thick Copper PCB?

 Drilling PCB

You find the use of a CNC (Computer Numerical Control) machine ubiquitous in the drilling of holes on the substrate.

Since thick copper PCBs are mass-produced, the substrates are stack together and fastened for simultaneous drilling action.

The CNC machine is fed instructions on the precise points where the holes are to be drilled.

The holes are then cleared of inordinate material resulting from the drilling process in a process called de-burring.

How are the Layers Connected Electrically?

To not break the circuit, a conductive path has to be created from one layer to another.

This is enabled by plating the drilled holes with a conductive material.

Also, this allows the layers to create a continuous path for electrical conductivity.

Drilled holes not intended for conductivity purposes are plugged.

They may also be drilled later when the panels are cut down to individual circuit boards.

How is the Circuit Pattern made on Thick Copper PCB?

The circuit pattern on the thick copper PCB provides the electrical path for the components.

In the thick copper PCB, this path is made of copper with a heavy weight-bearing.

There are two approaches to the creation of the circuit pattern.

The thick copper can be plated on the substrate surface in a precise manner as envisioned by the pattern.

This is referred to as an additive procedure as non-integral parts absent in the pattern are ignored.

Besides, the thick copper can also be blankly plated on the whole substrate surface and then the parts not in the pattern removed.

This process is called subtractive and it leaves only the desired pattern of thick copper.

Using the additive approach, the following steps are followed.

• Degreasing is carried out on the substrate surface’s foil.
• The panels are then vacuumed to combine them with a layer of material with high photo-resistivity. This eliminates air particles between the surfaces and allows the surface molecules to diffuse on exposure to ultraviolet radiation.
• A mask with the circuit pattern is placed over the surface before UV radiation exposure. This light illuminates the pattern diffusing the photo-resistive molecules there.
• A basic solution used as a developer is added to the surface on the removal of the mask. This solution dissolves the irradiated particles exposing the copper layer underneath in the circuit pattern.
• Using electroplating procedure and with the foil acting as a cathode, copper is filled up over the exposed pattern. Since the other panel surface is still with photo-resistive material, plating does not occur there. The thickness of the copper is determined by the plating procedure.
• The plated copper is also plated with a coating for protective purposes dissuading against oxidation and other fabrication processes. A tin-lead compound can be used for this coating.
• The rest of the photo-resistive layer is removed through dissolution. The remainder of the copper film is dissolved in acid. The plated coating over the copper prevents the copper plating from acidic corrosion.
• Contact extensions that provide a connection to the thick copper PCB are added at the substrate edge.

These extensions are then plated in a triple action where tin-lead is added before overlaying with nickel and eventually gold.

• The protective coating over the thick copper is finally removed via oxidation exposing the thick copper circuit pattern.

The tin-lead composition can also be removed via a reflow technique. Here, an oven or hot bath is used to melt the tin-lead.

How are the Components Attached to the Thick Copper PCB?

Before the attachment of the components, the panels with the thick copper pattern print are enclosed in epoxy.

This offers protection to the circuit during attachment of the components.

Furthermore, they are marked for component positioning and instructions before chopping them up into singular boards.

During component attachment, automated machines are used in attaching the components to their marked positions.

Typically, a single machine will be used to place a single component. This way, several robotic arms are used for different components.

For surface mounted thick copper PCBs, a process to smear the component contacts with a paste for solder is undertaken.

This will be followed by the component placement.

Smaller components are placed by a rapid shooter while some larger ones can be placed manually.

Component placement is succeeded by the fastening of the components to the thick copper PCB by soldering.

For through-hole components, the soldering process is for individual components.

You find this takes a longer time.

Where the board components are surface mounted, the components are simultaneously attached by a heat treatment called reflow.

Here, the solder paste is melted and as it sets, it attaches the component to the printed circuit.

Excess solder dregs are removed by solvents which will be selected contingent to the solder used.

For thick copper PCBs not intended for immediate use, single packaging is undertaken in plastic packages. They are then boxed for shipping purposes or storage.

How do you Control Quality of Thick Copper PCB?

Yes, they are.

The manufacture of thick copper PCBs is undertaken in a controlled environment free of dust and other particles.

This is because the presence of such particles could hamper the effectiveness of the processes undertaken during the manufacturing process.

You also find that at every step, inspection is carried out to identify any visible flaws.

Simple electrical procedures are also carried out to identify electrical flaws.

Due to the highly automated processes, a single error can result in great loss.

Some notable faults include:

 Components on thick copper PCB

• Misalignment of the panels which may result in the erroneous drilling of holes or placement of components.
• Movement of components out of the required position could encroach on adjacent circuit paths and neighboring components.
• Inadequate and/or inaccurate application of solder paste which can lead to a loose component or one attached at the wrong position.
• Overheating or under heating at the ovens.

Ignoring quality control during the reflow process to attach components, for example, can result in a loose component.

This may ultimately result in the eventual detachment of the component and failure of the circuit system where the board is used.

What is the Best Approach for Thick Copper PCB Testing?

Testing is important in determining the quality and reliability of your product.

Therefore, testing should be planned for with considerations made for the methodology to be used and the apparatus to help in the process.

Using computer test programs, you can simulate and predict areas of fault.

Additionally, this will help in reducing the actual occurrence of an error and mitigating it in advance.

However, these programs may themselves fail to require actual tests to serve as back-ups.

The following approaches are useful in testing a thick copper PCB.

• In selecting a test method, one that is implemented on one side is favorable.

This is because testing both sides of the board is a costly venture and without extra benefit.

• When carrying out the test procedure, there should be different points of focus.

These points should be exclusive of the leads to components and/or solder pads.

• You should identify test points by creating grids of not less than a millimeter. Making test grids smaller can be damaging to the test points.
• Since testing might involve the creation of a test apparatus, you have to identify components by height. This helps in the design
• of the fixture.
• For reliability ion the conductivity of the board, the test point needs to be covered by solder. You need to avoid having points covered with the solder mask as test points.

How are Thick Copper PCBs Tested?

The testing of thick copper PCBs is important.

Testing helps determine whether they meet the functional requirements and whether they will achieve the desired performance levels.

By testing PCBs you can confidently inform on what to benefit to derive from their use.

Tests are made to determine the response of the PCBs at different extreme conditions such as temperature and humidity.

Tests can also elaborate on the functionality of the PCB when under certain factors such as heavy vibrations and impact.

Some common tests undertaken on thick copper PCB are as follows.

· Bare-board Test

This test is also called the electrical test or e-test.

It is carried out just before the components are placed on the thick copper PCB.

This test checks for spots that open the circuit or those that could short the circuit.

A short circuit is a circuit connection that joins two points that are not supposed to be connected.

Contrarily, an open circuit identifies a lack of connection between two points that are supposed to be connected.

A computer-aided system is used in controlling a tester as it checks point voltages of all contacts.

Some contacts are expected to show voltage values and those that are not.

For contacts not expected to show voltage and they do, this indicates a short; otherwise, it’s an open circuit.

· Functional Test

This test seeks to determine the correctness of a thick copper PCB’s functional ability.

It is carried out upon placing the components on the circuit trace of the thick copper PCB.

Here, the thick copper PCB is connected as it would to an electrical source.

The connectors are checked to determine their responses upon receipt of electrical impulses.

Also, the impulses are recorded and then compared to the expected responses.

A thick copper PCB passes this test when its determined responses are close or similar to the expected responses.

The functional test has the advantage of testing the working of components as they would in operation.

You also find that this test unearths errors in the design in addition to timing difficulties.

However, this test is faced with shortcomings such as the time it takes to develop relevant software.

Additionally, performing this task takes time and requires individuals with advanced know-how.

Also, while establishing faults might be a good thing, it means a necessary overhaul of the thick copper PCB.

An overhaul can be credited to the non-localization of errors.

This creates a large coverage that needs to be re-examined.

· In-circuit Test

This test is carried out on a complete thick copper PCB.

With this test, components are individually examined through probing.

To carry out individual tests on components, other components have to be isolated.

For analog circuits, adjacent components to that being tested are guarded whereas digital circuits entail the use of latching for isolation.

This test type has the major advantage of providing an exact fault point and of not creating faults as a result.

You also find the in-circuit test can unearth several faults at the same time while requiring no complex development of software.

Additionally, the test can be carried out on an unpowered thick copper PCB.

You, however, find this test is limited by its use of costly apparatus to carry out the test.

Then again, having to individually test components takes a long time.

You also cannot establish the interrelation of components with the need for access to all circuit nodes.

What are the Safety Considerations in the Manufacture of Thick Copper PCB?

When making thick copper PCBs, safety measures are taken to protect the workers and the environment.

You find that making the thick copper PCB requires a lot of soldering procedures at different levels.

Solder contains lead which is an element with high toxicity.

To protect workers lead which is poisonous, thick copper PCB manufacturers provide personal protective equipment.

Such equipment includes gas masks to protect from the lead-induced fumes, gloves for use when handling solder and overcoats.

Additionally, you find that thick copper manufacturing is carried out in controlled environments.

Apart from ensuring quality, this helps in controlling emissions such as fumes containing lead.

As lead is a hazardous element, releasing the fumes into the atmosphere is dangerous.

The controlled environment ensures the fumes are filtered and cleaned before release.

Filtration ensures traces of lead are extracted from the discharge and only fumes meeting environmental thresholds released.

Beyond manufacture, thick copper PCBs are recycled when they become outdated.

Materials used in the manufacture of thick copper PCB are not biodegradable and pose a hazard to the environment.

Recycling ensures the threat to the environment is eliminated or reduced.

Are Thermal Interventions necessary for Thick Copper PCB?

Yes, they are.

The thick copper PCB is used in applications requiring large currents.

This feature is accompanied by large thermal energy dissipation which needs interventions for effective management.

You also find different materials used in the manufacture of the thick copper PCB with different coefficients of expansion.

The problem is exacerbated by the use of materials with wider variances in the CTE and different quantities.

Furthermore, external temperature changes will affect the functionality of the thick copper PCB if left unchecked.

Not to mention, the effect of individual components that can contribute to the power dissipated through heat loss.

Thermal interventions are necessary to prevent building up of strain that could result in mechanical stress.

Stress could be damaging to the thick copper PCB resulting in breakage that could create open circuits.

How are Leadless Ceramic Chips attached to the Thick Copper PCB?

Ceramic compounds have a low coefficient of thermal expansion that allows them compatibility with several materials.

This is because a change in temperature conditions does not adversely affect their structural composition.

For small leadless ceramic chips, attachment to the thick copper PCB can be achieved through soldering.

You find this approach feasible due to the low response rate to thermal changes.

Large leadless ceramics can be attached in the following ways.

• They can be mounted on sockets present on the PCB
• These chips can also be attached to leads that can be soldered to the thick copper PCB.
• You can also attach an organic surface to the thick copper PCB
• By fabricating a thick copper PCB with a metal base of a low coefficient of thermal expansion
• Furnish a substrate composed of ceramic compounds.

What Strategies can I use to Combat Rising Temperatures in Thick Copper PCB?

When temperatures are kept high in electrical components, their actual life cycle is greatly shortened.

High temperatures hamper the devices’ performance levels negatively affecting their reliability.

To mediate on temperatures that could result in thermal buildup, the following strategies can be useful to you.

• You can use components that have low power dissipation.
• The thick copper PCB design should be such that components that release large amounts of heat are ideally placed. This can be close to heat outlets or fans.
• Components can be modified by attaching cooling fins on them.
• The thick copper PCB substrate can be affixed with a heat sink or be made with materials with good thermal properties.
• A cooling fan can be integrated into the thick copper PCB to assist with air cooling.
• Direct or indirect intervention by liquid cooling can be used on the thick copper PCB.

What are some of the Features of Thick Copper PCB?

In manufacturing thick copper PCBs the following features can be identified.

These features dictate the use of the thick copper PCB.

• Thick copper PCBs can be made with a layer count of up to 16.
• A silkscreen width of at least 8 millimeters can be used for thick copper PCB.
• The weight of copper will be no less than 3 ounces per square foot.
• The thick copper PCB will be subject to impedance tolerance of 0.1.
• The laminates provided for thick copper PCVBS can be teflon based, ceramic, or made of glass-epoxy compounds.
• Drilled holes are typically made to at least 0.3 millimeters
• The width of the solder pad can have a measurement limit of five millimeters.
• The leveling of the solder can be done by using hot air.
• The solder mask clearance can be put to at least six millimeters.
• Gold and silver metals can be used for immersion.
• Thick copper PCBs can have a varying thickness between 105 to 400 µm.
• The solder masks can be provided in a variety of color options. Green, red, black, and blue are some of the color options available.
• The holes can be made with an aspect ratio of 10:1

How can you Fix a Trace on a Thick Copper PCB?

You can use the following steps to fix a trace on a thick copper PCB.

 Trace in thick copper PCB

• You will need to rid the thick copper trace of its coating. To do this, you can use a metal stick to gently scrub away the surface.

Scrubbing will reveal the copper underneath.

• Before you begin any work on the copper, you need to clean it. You can use abrasive clothe for this purpose.
• You can use different materials with similar properties instead of copper such as tin.

To prepare the copper before the recoating process, the application of flux is necessary.

• Solder wire can still be used instead of tin or copper. Recoat the trace by melting the wire over it. You can also attach a wire at both ends of the trace in repair.
• To provide a clean finish, use a remover to remove excess flux.

What are some of the Components on a Thick Copper PCB?

The thick copper PCB provides a path or trace for the connection of components.

It provides a simpler conductive channel as opposed to the previously used wire connections.

Each component has a significant role to play in pursuit of a general objective.

Some of the components that you will find on a thick copper PCB include:

· A battery Source

A battery is a voltage source on a thick copper PCB. A battery provides electrical energy to power the components.

This energy can be derived from an external source and stored in the battery.

 Electronic Resistor

The electronic resistor regulates the flow of current in the circuit of a thick copper PCB.

The electronic resistor is marked to identify its resistance value.

You can find several electronic resistors on a thick copper board.

· Electronic Diodes

Electronic diodes allow unidirectional flow of current.

Current flowing in the reverse direction is blocked.

There are many electronic diodes. Some common diodes on the thick copper PCB include the light-emitting diode which ignites with an electrical charge flow.

· Electronic Transistors

Electronic transistors are useful in switching applications.

You also find these components useful in amplifying electric charge.

Thick copper PCBs are used in different applications where switching or amplifying operation can be needed.

· Electronic Capacitors

Some operations do not require a full-time supply of electrical charges.

In these instances, an electronic capacitor suffices as it is used to store charge in small quantities.

Electronic capacitors will supply the charge stored in them and accept more from a voltage source.

What are the Reasons for the Failure of a Thick Copper PCB?

Thick copper PCBs can fail and measures are to be placed to intervene.

Intervention measures are only possible if you can identify the potential causes and act in preventing them.

The thick copper PCB can fail due to design issues, environmental factors, and component related failings.

Some reasons for failure include:

• Failure to correctly place the components
• Providing reduced tolerance between components at the design stage resulting in close packing of components
• Creating thick copper traces that are too close to each other creating room for shorts
• Issues related to solder processed including padding and landing
• Leakage of components that could have adverse effects on the board structure
• Using poor quality components or having components damaged on board
• Inefficiencies in connecting layers if the circuit boards
• Having a board thickness that cannot support the intended application
• Physical degradation of the board though cracking and breakage
• Accumulation of dust particles on the board
• Increased moisture content
• Sustained operation at high temperatures
• Electrostatic discharge of the substrate
• The mechanical strain that could result from thermal stress
• Serving out an extended life cycle

Why is Thick Copper PCB Green?

Thick copper PCB

The green color is usually due to the solder mask used to cover the thick copper PCB’s traces.

This is useful in preventing interaction with dust particles and moisture content.

Furthermore, the solder mask is available in other colors such as red, blue, black, orange, and even white.

Green solder masks are mostly used due to the research accepted findings that our eyes are more sensitive to the green color.

This way, visual inspection of the thick copper PCB can be easily carried out due to higher contrast.

Additionally, you find that over time research has been carried out on solder masks with green color pigments.

This way, pigments of other colors have lagged in the research process resulting in their limited use.

How are the Markings on a Thick Copper PCB made?

The markings on a thick copper PCB are useful in offering user information related to parts of the thick copper PCB.

They identify components, various settings, points of test, and serial information.

The markings on a thick copper aboard are printed by the use of a legend.

This legend is made with the complete information dose of the thick copper board and attached to the surface layer.

Legend printing can be done via silkscreen printing, photo imaging, or using an inkjet.

Silkscreen printing uses inks resistant to etching and was once the undisputed methodology.

Photoimaging uses a liquid medium to provide images more accurate than that of silk screen printing.

Inkjet printing allows variability that provides unique information.

What are Vias in Thick Copper PCBs?

 Different kinds of vias

Vias in thick copper PCB design provides electrical and thermal conductivity between PCB layers.

Vias are components located in drilled holes of the PCB that connect layers.

The thickness of the via contributes to its conductivity.

Copper terminations are provided for small holes and called via pads.

The vias are preventing from creating connections with adjacent traces by insulating them with anti-pads.

There are three types of vias available; the blind vias, the buried vias, and the through vias. Where there is more energy dissipation, more vias are used.

The blind vias are used in connecting an outer layer to an inner layer.

This is true for multilayer through copper PCBs.

Buried vias are used in PCBs with multiple layers providing a connection between two inner layers.

The through vias is relegated for connecting a pair of outer layers.

Is Soldering in Thick Copper PCB Harmful?

Soldering in a thick copper PCB is harmful only when the solder wire used contains harmful elements such as lead.

Otherwise, standard care still has to be taken when carrying out the soldering process.

The lead dust and fumes resulting from melting it can pose health hazards such as respiratory difficulties, digestive issues, and pains.

Care should be taken to avoid interaction with lead dust and inhalation of lead-induced fumes.

You can use gloves to handle lead-based solder to prevent from rubbing lead dust particles onto the skin.

Using gas masks will also help prevent the ingestion of lead-induced fumes.

To prevent irritation in the eyes, you can wear safety glasses.

What is the Difference Between a Solder Mask and a Paste Mask in Thick Copper PCB?

A solder mask is a protective coating in the thick copper PCB that has two major functions.

It covers the thick copper traces and prevents the formation of solder bridges.

A solder bridge is a connection between two solders that allows unintended conductivity.

A paste mask assists the soldering operation by covering parts missed by the solder mask.

The paste mask is especially useful when handling surface mounted components connecting them to pads.

It can also be applied for through-holes by masking the inside or covering the holes.

There you have it – all information you have been looking for about thick copper PCB.

At Venture Electronics, we design and fabricate a range of printed circuit boards.

For questions and inquiries, contact our technical staff.