In the pcb circuit board industry, more than commonly used glass fiber double-sided circuit boards will need to sink copper in the hole, so that the via hole has copper and becomes a via hole. However, pcb manufacturers will occasionally find that there is no copper or copper is not saturated in the holes after sinking copper after inspection during the production process. Now Sen Yan Xiaobian will briefly introduce several reasons for you. The reason for the hole without copper is nothing more than:
1. Drilling dust plugs the hole or the hole is thick.
2. There are bubbles in the potion when copper is deposited, and copper is not deposited in the hole.
3. Improper operation, staying too long in the micro-etching process.
4. There is line ink in the hole, no protective layer is applied, and there is no copper in the hole after etching.
5. The punching pressure is too high, (the designed punching hole is too close to the conductive hole) and the middle is neatly disconnected.
6. After sinking copper or after electroplating, the acid-base potion in the hole is not cleaned, and the parking time is too long, resulting in slow corrosion.
7. Poor penetration of electroplating chemicals (tin, nickel).
Thick copper circuit board
Improve the cause of the problem of no copper in the hole.
1. Add high-pressure water washing and desmearing processes to the holes that are prone to dust (such as 0.3mm or less hole diameter including 0.3mm). 2. Set the timer.
3. Change the printing screen and alignment film.
4. Improve the potion activity and shock effect.
5. Extend the washing time and stipulate how many hours to complete the graphics transfer.
6. Increase explosion-proof holes. Reduce the stress on the board.
7. Do regular penetration testing. Then, knowing that there are so many reasons that will lead to no copper open circuit in the hole, do we need to analyze each section? Should we go for preventive supervision in advance.
