The reasons for the above phenomenon and the improvement methods are as follows:

1. Open circuit caused by exposed substrate:

1. The CCL is scratched before storage;

2. The copper clad laminate is scratched during the cutting process;

3. The copper clad laminate is scratched by the drill bit when drilling;

4. The copper clad laminate is scratched during the transfer process;

5. The copper foil on the surface is bruised due to improper operation when stacking the board after copper sinking;

6. The copper foil on the surface of the production board is scratched when passing through the leveling machine.

ways to improve:

1. Before the copper clad laminate is put into storage, IQC must conduct random inspection to check whether the board surface is scratched or exposed on the substrate. If so, contact the supplier in time and handle it appropriately according to the actual situation.

2. The copper clad laminate is scratched during the cutting process. The main reason is that there are hard sharp objects on the cutting machine table. The friction between the copper clad laminate and the sharp object causes the copper foil to be scratched, resulting in the phenomenon of exposed bottom. Before using the material, the countertop must be carefully cleaned to ensure that the countertop is flat and free of hard objects.

3. The copper clad laminate is scratched by the drill tip when drilling. The main reason is that the spindle clamping nozzle is worn, or there are debris in the clamping nozzle that have not been cleaned up. Slightly longer than the length of the set drill tip, the height of the lifting is not enough when drilling, and the tip of the drill tip scratches the copper foil when the machine tool moves, resulting in the phenomenon of exposing the substrate.

4. The plate is scratched during the transfer process:

One. When carrying, the carrier lifts too many boards at one time, and the weight is too large. During the handling process, the board was not lifted, but was pulled up by the trend, causing friction between the board corners and the board surface and scratching the board surface;

5. After the copper is immersed, the board is scratched due to improper operation when the board is stacked after electroplating:

When the board is immersed in copper and the whole board is stored after electroplating, because the boards are stacked together, when there is a certain number, the weight is not small, and when the board is put down again, the corner of the board is downward, and there is a gravitational acceleration, forming a strong impact on the board surface. The impact will cause scratches on the board surface, exposing the substrate.

6. The production board is scratched when passing through the leveling machine:

One. The baffle of the template machine sometimes touches the board surface, the edge of the baffle is generally uneven and there are objects protruding, and the board surface is scratched when passing the board; the stainless steel drive shaft is damaged into sharp objects, and the copper surface is scratched when passing through the board. Expose the substrate.