Tool Wear in a Ceramic Microdrilling Processing Using Image Processing Methods

Abstract

A microhole array is a critical feature on a probe head for microprobe positioning in vertical probe cards. The precision of fabricating microholes affects the final positions of needle tips, and has a significant influence on the correctness of testing results. In the industry, the probe head is made of ceramic and the microhole array is mainly machined by a mechanical microdrilling process. Thus, measuring tool wear and the precision of the microhole is an important task in probe head fabrication. Only then can the functions of probe card be mastered effectively. This study presents a computer vision system that uses image processing methods to evaluate the microdrill wear. Five experiments with different drilling length and two trials of long-drilling were implemented. Wear measurements of the cutting lip and wear land discussed by image methods provide practical references for ceramic microdrilling.