Single-sided flexible circuit board on both sides of the manufacturing method

At present, many single-sided flexible circuit board manufacturing process, there are pre-punching method, mechanical scraping method, laser method, plasma etching method and chemical etching method.

1, prepared in advance:

Is the first place on the flexible film substrate required mechanical drilling or die punching way to open the window, and then laminated copper foil, making circuit graphics, etching circuit to form, and then laminated with a hole in the cover film, In this way, a flexible circuit board with double-sided conductor paths can be obtained.

2, mechanical scraping method:

The cover film which is to be partially exposed on the upper surface of the conductor layer covered with the insulating protective film is removed by mechanical scraping. The specific process is the use of mechanical processing methods, the glass fiber rods made of a certain geometry as a rotating grinding scraping tool is the conductor above the cover film to remove the exposed conductor copper made.

3, laser method:

This process is the use of laser drilling of tiny holes in high-density PCBs, common co2 or YAG and excimer lasers, and the removal of the cover film to expose the copper to form a single-sided board with double-sided vias. However, such as the use of co2 laser because it belongs to the infrared heat caused by the conditions, it is easy to make the edge is not clean, will be carbonized, the need to remove the carbonized part of the plasma, it is recommended that the best use of excimer laser, because it can produce very good cleaning edge.

4, plasma etching method:

That is, the cover film on the flexible printed circuit board is removed by plasma etching. However, it is necessary to protect the cover metal layer that is not necessary to be removed and to expose only the area of the cover film to be removed.

5, chemical etching method:

Is to use the chemical properties of materials, the use of acid, alkali method to remove the film. Such as the use of polyimide film substrate. Due to the very poor chemical properties of polyimide films, they generally do not dissolve under strongly corrosive or alkaline conditions and are immersed in hot corrosive solutions to dissolve them.

In the chemical process of making single-sided flexible circuit board with double-sided connection, in addition to the selection of a good etching solution, it is necessary to strictly control the etching without PI of the conductor portion to minimize the side etching because the etching accuracy of the opening window is very high High, otherwise it will directly affect the supporting effect of the lead