Do you know the process requirements of flexible circuit board?

Do you know the relevant knowledge of flexible flexible circuit board process requirements?

According to the combination of base material and copper foil, flexible circuit boards are divided into two types: adhesive flexible boards and non-adhesive flexible boards. Among them, the flexibility of the non-adhesive flexible circuit board, the bonding force between the copper foil and the substrate, and the flatness of the pad are better than those with the glued pcb single-layer board design , so the price of the non-adhesive flexible circuit board is more flexible than that of the glued one. Boards are more expensive.

We know that flexible PCBs can be bent, and are usually used in occasions that require bending. If the design or process is unreasonable, defects such as micro-cracks and open welding are prone to occur. Today, I will discuss with you the relevant knowledge about the process requirements of flexible circuit boards. Considering the price, most of the flexible PCBs on the market still use glued flexible PCBs.

According to the number of layers of conductive copper foil, flexible PCB can be divided into: single-layer board, double-layer board, multi-layer board and double-sided board, etc. The following takes single-layer flexible PCB as an example to explain the process requirements of flexible circuit boards.

After cleaning, combine the two with the rolling method. Then, the exposed pad part is electroplated with gold or tin for protection. In this way, the big board is ready. Generally, it is also punched into a small circuit board of the corresponding shape .

Single-layer flexible pcb belongs to the simplest flexible circuit board pcb single-layer board design . The raw materials are purchased in two types: substrate + transparent glue + copper foil and protective film + transparent glue. The required circuit is obtained by etching the copper foil and other processes; the protective film needs to be drilled to expose the corresponding pad. After the two are cleaned, the two are combined by the rolling method, and the exposed pad part is protected by electroplating gold or tin, and the large board is made in this way. Generally, it is also punched into a small circuit board of the corresponding shape.

Of course, there are also those who do not need a protective film to directly print the solder resist layer on the copper foil. The mechanical strength of the circuit board produced in this way will be deteriorated, but the production cost is relatively lower. This method is generally used for those who do not require high strength. Occasions where the price requirement is low. But the editor still recommends that you should use the method of sticking a protective film.

The above is the relevant knowledge about the process requirements of single-layer flexible circuit boards, and I hope it will be helpful to you.