Immersion silver and immersion tin are two different types of surface finished in PCB. They share some similarities. Here, flexible PCB supplier china will take you to look at the similarities and differences between these two PCB surface finishes.

Similarities

Immersion silver and immersion tin adopt the same process. These two surface finishes are environmentally friendly and budget-friendly. The cost of immersion tin PCB is very close to that of immersion silver.

Also, Immersion silver and immersion tin don’t have black pads. The process of immersion tin and immersion silver processes require micro-etching.

Both surface finishes require manufacturers to wear protective gloves during handling. This is because immersion silver and immersion tin can tarnish due to poor handling.

Immersion silver and immersion tin both experience whiskering. Therefore, this results in short circuits. Also, these two surface finishes need to be kept under good storage conditions. This is because they are prone to tarnishing.

Differences

Immersion silver has a longer shelf life than immersion tin. It can last for 12 months while immersion tin can only last for 6 months.

Immersion silver is more environmentally friendly than immersion thin. The presence of Thiourea during the immersion tin process makes it toxic. Also, Thiourea is carcinogenic.

Immersion silver consumes more power and water and power during its processing. However, immersion tin requires less power and water during its processing.

Also, immersion silver can withstand multiple reflows, unlike immersion tin. This makes it a preferred option for manufacturers. Immersion tin has a strong affinity to copper, which makes it react with copper. Therefore, the tin diffuses into copper. This reduces the solderability of the PCB surface. However, immersion silver doesn’t react with copper. This makes it have a longer shelf life.