Printed circuit board micro hole processing method

A PC board micro hole processing method adapted to make micro holes on a PC board, wherein said PC board comprising a substrate of glass fiber resin compound and at least one metal covering layer covered on at least one of top and bottom surfaces of said substrate, the method comprising the steps of:

• a) Removal of metal covering layer, where a chemical etching procedure is employed to remove metal material from predetermined areas of said substrate, enabling the predetermined areas of said substrate to be exposed to the outside;
• b) Plasma Via, where the PC board is put in a low-tension electric field of predetermined strength, and then a gas is filled into the low-tension electric field for enabling the filled gas to be decomposed into electrons, ions, or radical to cause a chemical reaction with the resin of said substrate at said predetermined areas, so that the chemical reaction lowers the molecules of the resin material and causes the resin material to be released in the form of vapor, and at the same time vaporized molecules thus produced are drawn away, causing the resin material to be etched layer by layer at said predetermined areas;
• and
• c) Chemical etching, where a chemical solution is applied to said substrate to remove the residual glass fibers left after the process of Plasma Via, finishing the desired micro holes.