Abstract
The smaller through holes of printed circuit boards (PCBs) are required for the multifunctional information communication devices. This paper describes some experiments on the effect of entry sheet (E/S) on the micro drilling quality of PCB. Especially the effect of the resin painted on E/S on the micro drilling quality was investigated. The effect was examined by performing the micro drilling tests of PCB using the aluminum E/S and the resin painted aluminum E/S. Resin films used were the polyethylene-glycol (PEG) based film and the wax-based film. The effect of the E/S on the position error of hole center was determined by measuring the centripetal action with the non-contact displacement sensor. The effect of the E/S on the hole wall roughness was also determined by examining the relationship between the drill temperature decrease during drilling due to the use of E/S and the adhesion of resin film to the drill. From these experiments, the followings were obtained : (1) On the position error of hole center, the wax-based film is better than the PEG-based film. (2) On the hole wall roughness, the PEG-based film is better than the wax-based film.
