On-machine measurement technique for dicing blade wear monitoring

Abstract

On-machine measurement technique for dicing blade wear monitoring. technique for dicing blade wear (attrition, abrasive and chipping) by using knife-edge interferometry (KEI) in a simple, high-accuracy, low-cost and convenient way. The proposed KEI utilizes interference between a transmitted wave and a diffracted wave at the edge of circular tool. In this study, a laser beam is incident on the dicing blade edge and the photodetector measured the interference fringes by scanning every 30 degree of the dicing blade. The relationship of difference roundness of the dicing blade established using the cross-correlation of the interference fringe. The difference roundness of the tool produces the phase shift (roundness difference) and the decay of oscillation (tool edge roughness) in the interferometric fringe. As a result, the difference roundness of dicing blade and lag of the KEI fringes between every angles showed a linear relationship 23.6 lag/um, and maximum roundness difference is 128 um (lag 3030). Cross-correlation R is shown from -0.06 to 0.11 each angles, but it should be defined the value of meanings. The dicing blade was scanned by rotating the tool using an interference fringe slope (1-9V, 0-140 um) for dynamic characteristics. The difference between dynamic and static state is about 16 um. It is possible to include spindle dynamic and shaft tilting motion error.