What are the types of PCB surface treatment processes?

With the quick development of modern digital
information technology, PCB manufacturing technology has actually also transformed greatly, and the
demands for item modern technology are getting greater and higher. Similar to the circuit card in mobile
phones and computers currently, some use gold and copper, that makes the advantages and negative aspects
of motherboard more apparent.

Top quality PCB helps everyone to recognize the surface innovation on printed circuit card and contrasts
the benefits and downsides of different PCB surface treatment processes and applicable scenarios.

From the appearance of the board processed by PCB, its appearance mainly has three colors:
gold-silver-light red. Regarding classification, gold is the most costly, silver is 2nd, and the most
affordable is light red. It is easy to see from the appearance whether the manufacturer has actually cut
edges. The parts of the circuit board are mostly pure copper, described as bare copper board.

1. The advantage of bare copper board is that the cost is fairly low, the surface area is flat, and its
weldability is better without oxidation. However be careful not to be affected by acid and temperature.
Copper is very easy to oxidize in the air after being positioned for a long period of time.

2. The gold on the immersion gold board is gold. Even if only a thin layer of conductor is layered, the
price of this has made up 10% of the expense of the entire circuit card. After immersion in gold
therapy, it is challenging to oxidize, can be stored for a very long time, and has a smoother surface.
It appropriates for welding some fine-gap pins and some gadgets with smaller solder joints, such as
mobile phone boards. Its cost is fairly high and the welding stamina is fairly bad.

3. The tin-spraying circuit board is silver. It sprays a layer of tin on the outside of the copper
circuit. It can help with welding, but it can not have the exact same long-term get in touch with
dependability as gold. It is very easy to oxidize and rust if utilized for a long time, resulting in
inadequate call. It is typically utilized on the circuit boards of some small digital items, and its
rate is cheap.

4. In the SMT manufacturing facility, the OSP process board is also called natural flux movie. Due to
the fact that it is an organic substance, not a steel material, it is less expensive than the
tin-spraying process.

It has all the advantages of bare copper plate welding. Also ended circuit card can be treated once more
on the surface, however they are easily impacted by acid and moisture. If the storage space time is too
long, more than 3 months, the surface treatment need to be done again. OSP is a protecting layer, so the
test point requires to be published with solder paste to get rid of the original OSP layer prior to the
determine can be spoken to for electric testing.