Structure of flexible circuit board
In accordance with the number of layers of copper foil, divided into single board, double layer board, multilayer board, double-sided board, etc.. The structure of the single layer board: the structure of the flexible plate is the most simple structure of the flexible plate. Usually substrate + transparent glue + copper foil is a set of raw materials to buy, protective film + transparent plastic is another kind of raw materials to buy. First of all, copper foil etching process to get the required circuit, the protective film to be drilled to expose the corresponding pad.
General substrate + transparent adhesive + copper foil is the first process of making holes. First in the base material and copper foil drilling, cleaning after plating on a certain thickness of copper, the hole is done. The production process is almost the same as that of a single plate. The structure of the double sided board: both sides of the two sides of the board, mainly used to connect with other circuit boards. Although it is similar to the single plate structure, the manufacturing process is very different. Its raw materials are copper foil, protective film + transparent adhesive. First, according to the requirements of the position of the pad on the protective film on the hole, and then put on the copper foil, the corrosion of the pad and the lead and then paste another hole drilled protective film can be.
The structure of the double deck: when the circuit is too complex, single layer plate can not be wiring or the need for copper foil to shield the ground, it is necessary to select the use of double deck or even multilayer board. The most typical difference between multilayer and monolayer is the increase of the hole structure to connect the copper foil.
In this way, the board is ready. General stamping into the corresponding shape of the small circuit board. There is also no need to protect the film directly on the copper foil printed solder layer, so that the cost will be lower, but the mechanical strength of the circuit board will be poor. Unless the strength requirements are not high but the price needs to be as low as possible, it is best to use the method of sticking protective film.
After cleaning and rolling method to combine the two together. And then in the exposed part of the pad, such as gold-plated or tin protection.
