Metal half hole (groove) refers to the second drilling and shape process after the first drilling hole is perforated, and finally the metallized hole is retained (slot) half, that is, the metallized hole on the board edge is cut in half. In the PCB industry, it is also called stamp hole. The hole edge can be directly welded with the main edge to save connector and space. It often appears in the signal circuit. What is the production process flow of half hole PCB?

The production process flow of half hole PCB includes the following steps:

1. Outer circuit design;

2. Base plate pattern electroplating copper;

3. Electro tinning of substrate pattern;

4. Half hole treatment;

5. Film removal;

6. Etching.

Process interpretation:

(1) How to control the product quality after forming the semi metallized hole on the plate edge, such as the warping and residue of copper thorn on the hole wall, has always been a difficult problem in the processing process.

(2) For this kind of PCB with a whole row of semi metallized holes on the edge of the board, the hole diameter is relatively small. Most of them are used for the daughter board of the motherboard, and are welded with the pins of the motherboard and components through these holes. If there are copper thorns left in these semi metallized holes, when the manufacturer carries out welding, it will lead to loose welding feet and false welding, and seriously lead to bridge short circuit between the two pins.