Wiring interval 12 m epoxy flexible PCB appearance

Wiring 12 m interval on production technology of flexible epoxy printed circuit boards before the advent of this technology in Japan in the development of Dongli film board in COF, than the existing production level of the highest level of 30 m and 20 m interval trial level interval, a substantial increase in the density of the package, IC package is mainly used for liquid crystal drive IC small package and mobile phone terminal.

It is reported that the use of the development of the technology to make the wiring width of 5 m, the spacing between the wiring of the M wiring pattern of 7. The company has announced in March 2004, in the COF film circuit board can achieve 25 m wiring interval, the technology shows that further improve the wiring density. According to experts, in order to improve the processing accuracy of the flexible film substrate, we must develop the control of the expansion process. Dongli days ago by the common method has been successfully developed, compared with the past developed interval for the production of polyimide film for wiring circuit board technology of high density package IC 12 M. Through the control of floor expansion, for IC pins and solder bumps can make accurate pattern in a wide area, also by improving the packaging density also developed a circuit between even very close, but also to ensure that the high insulation film surface processing technology.

The invention adopts a semi additive method for making a pattern gradually by using an electrolytic plating. In the flexible circuit board in the production of the existence of such a phenomenon: due to repeated heat treatment and wet process, which led to changes in temperature and water, resulting in the polyimide film floor expansion and contraction are unable to restore the original state. As the manufacturing technology of polyimide film material and in the past, through the improvement and adjustment of the key technologies such as the improvement of the photoresist material, in the manufacturing process to control the expansion of the film substrate. Due to the control of the expansion of the floor, in addition to the accuracy of the local pattern, for the majority of IC welding convex can be in the range of a few 10mm to accurately form a pattern. This position accuracy reached 0.001%, more than in the past to improve the figure of about 1, the highest in the past is probably + + 0.04%. In addition, the fluctuation range of film thickness is controlled to within 10%.