Kazuhide Isaji

Concurrent in-line inspection system for CO2 laser drilling machine

We describe the concurrent in-line inspection system, which controls the CO2 laser drilling machine for printed wiring boards. The performance of a CO2 laser drilling process was improved drastically by the introduction of this inspection system. The principle of this inspection systems is based on the relationship between the exposed bottom area of the inner layer copper foil in via hole and the intensity of the reflected laser beam. The end of drilling process is detectable by the saturation of the reflected laser beam intensity generate at the copper foil surface of the blind via hole. We have carried out the drilling process for glass-cored epoxy substrate and have observed that the productivity of the drilling process i increased by 30 percent due to this inspection system.

Development of CO2 laser drilling system controlled by concurrent in-line inspection monitoring for printed wiring boards

The performance of a CO2 laser drilling system was improved by real-time process control with concurrent in-line inspection monitoring for printed wiring boards. The principle of the concurrent in-line inspection monitoring method was based on the relationship between the exposed bottom area of the inner layer copper foil in the via hole and the intensity of the reflected laser light. The end of the drilling process was detectable by the saturation of the reflected laser light intensity generated at the copper foil surface of the blind via hole.In this paper, the development of the CO2 laser drilling system for printed wiring boards, which is controlled by concurrent in-line inspection monitoring, is described. We carried out the drilling process for glass-cored epoxy substrate and observed that the productivity of the drilling process was increased by about 30 % due to control by concurrent in-line inspection monitoring.The performance of a CO2 laser drilling system was improved by real-time process control with concurrent in-line inspection monitoring for printed wiring boards. The principle of the concurrent in-line inspection monitoring method was based on the relationship between the exposed bottom area of the inner layer copper foil in the via hole and the intensity of the reflected laser light. The end of the drilling process was detectable by the saturation of the reflected laser light intensity generated at the copper foil surface of the blind via hole.In this paper, the development of the CO2 laser drilling system for printed wiring boards, which is controlled by concurrent in-line inspection monitoring, is described. We carried out the drilling process for glass-cored epoxy substrate and observed that the productivity of the drilling process was increased by about 30 % due to control by concurrent in-line inspection monitoring.

Development of the enhanced concurrent in-line inspection system for CO2 laser drilling machine

The performance of the concurrent in-line inspection system in CO2 laser drilling process has improved by the defect pattern estimation algorithm. The optical detection principle of the system is based on the relationship between the reflected laser intensity from the bottom copper foil in via-hole and the area size of the exposed copper surface. The principle and the advantage of the enhance concurrent inspection system was described. Using the improved concurrent inspection system, the etched hole diameter and defect of PWB can be examined. This function has a capability to substitute AOI function. As a result, reliability and throughput in PWB drilling process has been improved.