What are the production difficulties in the process of circuit board proofing?

 pcb printed circuit board in communications, medical, industrial control, security, automotive, electric power, aviation, military, computer and other fields occupy an important position; with the increase in product features, the line is more and more dense, the production is also increasingly difficult. PCB in mass production before, are required to proof, to determine the sample there is no problem after the production. Then PCB proofing will encounter what difficulties? Let's look at it together.

1, the inner layer of the line production difficulties

Multilayer board lines have high speed, thick copper, high frequency, high Tg value of various special requirements for the inner layer wiring and graphics size control requirements are increasingly high, the inner layer signal lines, the line width and spacing are basically about 4mil or less, the board layer, the core board thin production is easy to wrinkle, these factors will increase the production costs of the inner layer.

2, alignment difficulties between the inner layer

The number of layers of multi-layer board is increasing, and the alignment requirements of the inner layer are getting higher and higher; the film will rise and shrink under the influence of temperature and humidity of the workshop environment, and the core board will be produced with the same rise and shrinkage, which makes the alignment accuracy between the inner layers more difficult to control.

3、Difficulties of pressing and laminating process

The stacking of multiple core boards and PP (semi-cured sheet) is prone to delamination, slippage and vapor pack residue problems when pressing. If the number of layers is large, the control of rise and shrinkage and the compensation of size coefficient cannot be kept consistent; if the insulation layer between layers is thin, it will easily lead to the problem of inter-layer reliability test failure.

4、Difficulties of drilling production

Multilayer board using high Tg or other special plates, the roughness of different materials drilling is not the same, increasing the difficulty of removing the slag in the hole. High density multilayer board hole density, low production efficiency, easy to break the knife, different network over the hole between the hole, the hole edge too close will lead to CAF effect problems. Therefore, in order to ensure the high reliability of the final product, it is necessary for the multilayer board manufacturer to control the production process accordingly.