The development of circuit boards has been derived from a lot of types, but most of them can be divided into two kinds, respectively, rigid and flexible circuit boards, and today we will talk about the structure of flexible circuit boards.
General circuit boards are in accordance with the number of layers and thickness of conductive copper foil to divide the layers, they can be divided into single-layer board, double-layer board, multi-layer board and double panel, their structure is also different, the following to introduce their different properties where.
Single-layer plate structure: this is the simplest structure of the flexible plate, usually substrate + transparent adhesive + copper foil a set of purchased raw materials, and protective film + transparent adhesive is another purchased raw material; First of all, the copper foil should be etched and other processes to get the required circuit, the protective film should be drilled to expose the corresponding pad, and then the rolling method is used to combine the two, and then the exposed pad part of the electric gold plating or tin protection, so that the big board is done, and then it needs to be stamped into the corresponding shape of the small circuit board.
Double-layer board structure: When the line is too complex, single-layer board can not be wired or copper foil is required for grounding shielding, it is necessary to choose double-layer board or multi-layer board.
Multi-layer board structure: The most typical difference between multi-layer board and single-layer board is the addition of a perforated structure to connect each layer of copper foil, the first processing process of the general substrate + transparent adhesive + copper foil is to make perforated; First, the substrate and copper foil are drilled, and then a certain thickness of copper is plated after cleaning, so that the hole is done, and the production process is almost the same as that of the single layer plate.
Double panel structure: both sides of the double panel have pads, which are mainly used for connecting with other circuit boards. Although it is similar to the single-layer plate structure, but the production process is very different, its raw materials are copper foil, protective film + transparent adhesive, first of all, according to the welding pad position requirements in the protective film drilling, and then paste the copper foil, and then corrode the welding pad and lead after pasting another drilled hole protective film can be.
Although these types of flexible circuit board structure are different, many production processes have the same place, but in some basic places to increase different processes, used to correspond to different fields.