A: Copper is commonly used to make PCB traces on printed circuit boards due to its excellent electrical conductivity, ease of fabrication, and other advantageous properties. Here are some reasons why copper is the preferred material for making PCB traces:

  1. Electrical Conductivity: Copper is an excellent conductor of electricity, allowing signals to flow with minimal resistance. This is crucial for maintaining the integrity of signals and minimizing losses as they travel along the traces.
  2. Low Resistance: Copper’s low electrical resistance ensures minimal voltage drop across the traces. This is important for maintaining signal quality and minimizing power loss.
  3. Thermal Conductivity: Copper has high thermal conductivity, which helps dissipate heat generated by electronic components and traces. This property is crucial for preventing overheating and ensuring the reliability of the circuit.
  4. Ease of Etching: PCB traces are created through chemical etching. Copper’s susceptibility to etching processes makes it easy to remove excess copper from the substrate and leave behind the desired trace pattern.
  5. Adhesion: Copper adheres well to most common PCB substrates, ensuring good mechanical stability and reducing the risk of delamination or detachment during manufacturing and use.
  6. Solderability: Copper is easily solderable, making it suitable for attaching components to the PCB through solder joints. This property is essential for assembling electronic circuits.
  7. Availability and Cost: Copper is abundant and relatively affordable, making it a cost-effective choice for use in PCB manufacturing.
  8. Compatibility with Other Materials: Copper is compatible with many other materials commonly used in PCB manufacturing, including solder masks, protective coatings, and finishes.
  9. Fine Tracing and High Density: Copper’s malleability and ductility allow it to be formed into fine traces with high precision, creating densely packed circuitry on modern PCBs.
  10. Electromagnetic Shielding: Copper traces can act as electromagnetic shields, reducing electromagnetic interference (EMI) between different parts of the circuit or neighboring circuits.

While copper is the preferred choice for PCB traces, it’s worth noting that there are alternatives, such as silver and gold, which also have excellent conductivity properties. However, these metals are generally more expensive than copper and may have other limitations that make them less suitable for widespread use in PCB manufacturing.

Copper Cladding on Substrate before Etching PCB Traces
Copper Cladding on Substrate before Etching PCB Traces