Why are individual vias blocked after the circuit board is mounted?

This may be a problem that many circuit board companies will have. Let me analyze the specific reasons for everyone.

After the customer plug-in test, it is found that the via (through hole) is not connected, and the normal conduction test can be performed before the plug-in. There is no drilling deviation in the appearance, which is mainly caused by the following five reasons:

First: insufficient hole copper;

Second: the hole wall is too rough

Third: Drill the dust plug hole

Fourth: Drilling a broken tool to make up the hole

Fifth: Poor solder mask plug hole

In the control of the problem of unconnected vias, the copper hole is the most important link. The automatic sinking copper wire of Honglian Circuit is not small:

Maintenance: The maintenance department will maintain the equipment regularly every week

Analysis: The copper sinking department works in two shifts. It works 24 hours a day. Every shift will analyze and adjust the concentration of the potion to reach the best value. The copper sinking tank uses computer numerical control to automatically add potion.

Inspection: The inspection method of copper sinking wire is mainly the backlight level inspection, and the level greater than 9 is qualified to ensure the quality of copper sinking and holeization

The detection methods include deposition speed test (the thickness of the copper layer in the standard time); glue removal speed (this is mainly for multi-layer boards that need to be glued); hole wall roughness detection