With the improvement of product performance, PCB is also constantly updated and developed. The circuits are becoming more and more dense, and more and more components need to be placed. However, the size of PCB will not only not increase, but become smaller and smaller. Therefore, if you want to drill holes in the board at this time, you need considerable technology.
There are many PCB drilling technologies. The traditional method is to make inner layer blind holes. When laminating multi-layer boards one by one, two double-sided boards with through holes are first used as the outer layer, and then pressed with the inner layer boards without holes, and then the blind holes filled with glue will appear. The blind holes on the outer layer are drilled mechanically. However, when making machine-drilled blind holes, it is not easy to set the drilling depth of the drill bit, and the tapered hole bottom affects the copper plating effect. In addition, the process of making inner layer blind holes is too lengthy and wastes too much cost. The traditional method is becoming less and less suitable.
In addition to the carbon dioxide drilling and laser drilling we introduced earlier, the commonly used PCB microvia technologies now include mechanical drilling, photosensitive drilling, laser drilling, plasma etching and chemical etching.
Mechanical drilling is made by high-speed mechanical processing, among which the most important is the drill bit. The drill bit is generally made of tungsten-cobalt alloy. The alloy is based on tungsten carbide powder and cobalt as a binder. It is sintered at high temperature and high pressure. It has high hardness and high wear resistance and can smoothly drill the required holes.
Laser drilling is the process of cutting with carbon dioxide or ultraviolet lasers. The gas or light forms a beam with strong thermal energy, which can burn through the copper foil to create the required holes. The principle is the same as cutting, mainly controlling the beam.
Plasma is also called plasma. The particles that make up plasma are relatively far apart and are in a state of continuous collision at random. Its thermal motion is similar to that of ordinary gas. Plasma etching is mainly used for PCBs with resin copper layers. It uses oxygen-containing gas as plasma. After contacting copper, it will produce an oxidation reaction, thereby removing the resin material to form holes.
Jinbaize has previously introduced that if the objects left on the PCB cannot be cleaned by general methods, they can be removed by chemical cleaning, which allows the chemical agent to react with the residue. The same is true for drilling. Using chemical agents, dripping them on the place where the hole needs to be drilled, the copper foil, resin, etc. can be corroded, and finally a hole is formed.
提升卡
变色卡
千斤顶
The one upstairs is so handsome
京公网安备 11010802033920号