PCB surface finishing is a crucial manufacturing process. To ensure the reliability, solderability, and long-term performance of the PCB, surface finishing must be performed. With the development of environmental protection requirements, the demands are becoming increasingly stringent. Nowadays, more and more products and countries require lead-free and halogen-free solutions.

What is PCB Surface Finishing?

Typically, the circuit layer of a PCB is made of copper, but copper is prone to oxidation, therefore we will apply a layer of solder mask on the copper circuit layer to protect it. However, when we need to solder components onto the PCB,  solder pads must be built. To protect the pads from oxidation while maintaining their solderability, we perform surface finishing on the PCB.

Why is PCB Surface Finishing Necessary?

Firstly, we need to protect the copper circuit layer from oxidation and mechanical damage. Secondly, we need to maintain the solderability and electrical performance of the copper.

What are the Common PCB Surface Finishing Methods?

Depending on different requirements, we can use various surface finishing methods to meet different needs. The diagram below shows the surface finishing options provided by PCBWay.

When selecting a surface finish between HASL with lead and HASL lead free for your PCBs, we highly recommend HASL Lead-Free over traditional HASL with lead, as it aligns with global environmental standards and long-term reliability goals.

Why Choose HASL Lead-Free?

✔ RoHS & REACH Compliant – Meets strict international regulations (EU/China/US)

✔ Eco-Friendly & Safer – Eliminates toxic lead exposure in manufacturing and recycling

✔ Future-Proof – Avoids redesign costs if lead-free compliance becomes mandatory

✔ Comparable Performance – Maintains strong solderability with minor process adjustments

While we still offer HASL with lead for legacy applications, lead-free is the sustainable choice for most modern electronics.

Please click here to learn more about the types of surface finish.