Many engineers or customers have not seen the PCB processing process at the PCB processing plant site. Today, I will briefly describe the PCB processing process for you, so that you can have a general impression of the PCB processing process.
1, The cutting
The raw material of copper clad laminate, cut to the size we need, is called cutting.The process of opening materials is to improve the utilization rate of raw materials and reduce the price of veneer.
Remove contaminants from the copper surface, increase the roughness of the copper surface, and facilitate the subsequent film pressing process.
3, Pressure film
The copper surface of the treated substrate is coated with an anticorrosive dry film by hot pressing.
To transfer an image from the original plate to a photosensitive substrate by irradiation.
The dry film without chemical reaction is washed away by lye action, and the dry film with chemical reaction is left on the surface of the plate as a protective layer against corrosion during etching.
The copper exposed after development is etched off by using liquid medicine to form the inner circuit pattern.
7, To film
A strong alkali is used to peel off the corrosion resistant layer of the copper surface to reveal the line pattern.
CCD is used to flush out the positioning hole and rivet hole.
9. AOI inspection
Through automatic optical inspection, compare with sample or original data to find defects.
Drill through holes for connecting lines between layers on the PCB surface.
11, Heavy copper
Remove burr on edge of hole to prevent poor plating hole.
Prevent metal oxidation by electrolysis, and improve wear resistance and electrical conductivity.
13, Resistance welding
Set aside the parts on the PCB that need to be welded, and cover the other lines and copper surface to improve the electrical performance.
14, Screen printing
Convenient for circuit maintenance and installation, logo design and code words for annotation.
15. Surface treatment
PCB surface treatment for better welding reliability, thermal stability, and surface evenness.
16, V - CUT
To facilitate the smooth cutting of the original board into a veneer process.
17. Electrical testing
Perform bare board test for PCB electrical performance to meet customer requirements.
All PCB boards will have the above processing flow, but the number of processing flow will be different depending on the number of layers of PCB.