PCB News - Explanation of relevant knowledge about single-layer flexible circuit board process requirements

Explanation of relevant knowledge about single-layer 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 adhesive-free flexible circuit board, the bonding force of the copper foil and the substrate, and the flatness of the pad are better than those with adhesive. Therefore, the price of the adhesive-free flexible circuit board is more expensive than the adhesive flexible board.

We know that flexible PCBs can be bent, and they are usually used in occasions that need to be bent. If the design or process is unreasonable, defects such as micro-cracks and open welding are prone to occur. Today, the editor of PCB factory will discuss with you the relevant knowledge of flexible circuit board process requirements. Considering the issue of price, most flexible PCBs currently on the market still use flexible PCBs with glue.

Flexible PCBs can be divided into single-layer boards, double-layer boards,multilayer boards and double-sided boards according to the number of layers of conductive copper foil. The following takes single-layer flexible PCBs as an example to explain the process requirements for flexible circuit boards.

After cleaning, use the rolling method to combine the two. Then the exposed pad part is electroplated with gold or tin for protection. In this way, the slab is ready. Generally, small circuit boards of corresponding shapes are also stamped.

Single-layer flexible PCB is the simplest flexible circuit board. The raw materials can be purchased in two types: base material + transparent glue + copper foil and protective film + transparent glue. Wait for the required circuit by etching the copper foil and other processes; the protective film needs to be drilled to expose the corresponding pads. After cleaning the two, use the rolling method to combine the two, and use electroplating gold or tin to protect the exposed pad part. This is how the large board is made. Generally, small circuit boards of corresponding shapes are also stamped.

Of course, there are also solder masks that directly print the solder mask on the copper foil without a protective film. The mechanical strength of the circuit board will be worse, but the production cost is relatively low. This method is generally used for those who do not require high strength. Occasions with low price requirements. But the editor still recommends that everyone use the method of sticking a protective film.

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