With the rapid development of electronic products, PCBs (printed circuit boards) have become a core component of electronic devices. But did you know that a seemingly minor parameter—copper thickness—actually determines the performance and lifespan of the entire circuit board?

Today, let's delve deeper into the crucial role of copper thickness in PCB manufacturing!

What is PCB copper thickness?

In PCB manufacturing, copper thickness refers to the thickness of the copper foil, commonly measured in ounces (oz), which is the weight of copper foil per square foot. Common specifications include:

17.5μm (0.5oz)

35μm (1oz)

70μm (2oz)

Different copper thicknesses are suitable for different electrical performance requirements and application scenarios. Below, using Figures 1-3, we'll examine its three main roles in PCBs!

Copper is the primary conductive material on PCBs, and variations in copper thickness directly affect the overall conductivity of the board.

If the copper layer is too thin, the current-carrying capacity decreases, leading to signal attenuation and voltage instability.

If the copper layer is too thick, while it improves conductivity, it also increases cost and processing difficulty. It can also cause defects due to severe adhesive bleed.

Design Recommendation: 1oz copper thickness is the mainstream choice for conventional PCBs. For special requirements (such as high current), 2oz can be considered, but process compatibility should be considered.

In devices with increasing power consumption, good heat dissipation is crucial.

Copper not only conducts electricity but also conducts heat. Thicker copper layers distribute heat more quickly and evenly, helping to reduce component surface temperatures and extend component life.

In addition to selecting the appropriate copper thickness, copper can be added to unused areas to create additional heat dissipation paths, improving overall board heat dissipation efficiency.

PCBs are not only conductive networks but also crucial mechanical structures.

✔ A reasonable copper thickness improves the board's resistance to bending and reduces cracking and solder joint loss over time.
✔ It also enhances the strength of the solder pads, improving solder joint reliability and reducing cold and false solder joints.

For products requiring strong mechanical strength (such as automotive and industrial control), copper thickness is crucial!

In summary: Copper thickness may be a small factor, but it has a huge impact!

A high-quality PCB must have a copper thickness design that's just right.

For stable conductivity, the copper shouldn't be too thin.
For fast heat dissipation, the copper shouldn't be cut corners.
For high strength, the copper shouldn't be skimped on.

During design, it's crucial to consider various factors, including functional requirements, current flow, heat dissipation requirements, and manufacturing costs, to determine the optimal copper thickness.