Proposal of tool path generation for recycle pad in Chemical Mechanical Polishing based on piecewise linear interpolation method

Today, semiconductor structures have become multi-stratified in order to offer technical advantages and miniaturize electronic devices. The number of processes required to produce an integrated circuit chip is increased with the miniaturization of the chips. The increased consumption of polishing pads for CMP (Chemical Mechanical Polishing) has led to interest in recycling technology for CMP pads. In order to recycle worn CMP pads, we have to recut the grooves of the pad along the remaining grooves. However, the shape error of each pad must be taken into account, because the CMP pad has a margin of error caused in the manufacturing and CMP process. Moreover, burrs caused in the recutting process must be removed manually. In this study, we measured the circular and lattice grooves on the surface of the CMP pad using a 2D laser scanner.We modified the cutting-tool trajectory depending on the change of grooves, proposing a path-planning method that is applicable to the recycling of individual polishing pads.