Monthly Archives: December 2010

PCB development trends of advanced manufacturing technology

Posted by on December 28, 2010 No comments

Summary of domestic and international manufacturing technology for the future development trends of PCB production is basically the same discourse: namely high-density, high precision, small hole diameter, fine wire, fine pitch, high reliability,multi-layered, high-speed transmission, lightweight, thin thickness development, and in production to improve productivity, reduce costs, reduce pollution and meet the many varieties and small batch production direction.
As printed circuit boards level of technological development, we often use the line width, diameter, thickness / diameter ratio as the representative. Please see the level of PCB development process as follows:

Level of development of printed circuit boards technology:

Years
 1970
 1975
 1980
 1985
 1990
 1995
 2000

Aperture (mm)
 1.0
 0.8
 0.6
 0.4
 0.3
 0.15

Width (mm)
 0.25
 0.17
 0.13
 0.10.
 0.08
 0.05

Thickness / aperture ratio
 1.5
 2.5
 5
 10
 20
 40

 Hole density, number of holes / CM2
 4
 7.5
 15
 25
 40
 55

CMD Circuits is engaging in manufacturing the high quality and competitive cost printed circuit boards and flexible pcb for our customers.

Outline processing of flexible cirxuits

Posted by on December 9, 2010 No comments

Outline processing of flexible circuits usually use punching method. The tooling we have two kinds: simple tooling and hard tooling for punching.  Please see below the differences between these two molds:

Stripping of Flexible circuits

Posted by on December 3, 2010 No comments

Stripping of flexible circuits is intended to clear resist layer to expose the copper on the board after etching. Does operation of stripping of flexible circuits going smoothly, dependent on equipment design and preparation of the liquid two main parts.

Stripping is relative simple compare to etching of flex circuit with the complex machine. But the “film residue” filtering, and recycling waste shall be disposed properly.

The chemical liquid of stripping, generally use the traditional NaOH(based),solution concentration is about 1-3% in weight, and temperature of the solution between about 40-55 ℃. The major reasons to use the NaOH in our industry: for dry film with good solubility, low prices and easy got. However, according to the actual use of that low concentration of NaoH work not very well, so now the mostly use KoH instead of NaoH as the solution for stripping.
The chemical properties of KoH and NaoH are very similar, but because of the dissolution of K for the dry film with excellent performance, and enhance the effect of stripping. This way don’t need to change the existing production equipments and the filtering effect of the film residue are improved.