Multi-beam technology for defect inspection of wafer and mask

Abstract

Pattern defects and uninvited particles (residuals) probably appear on Mask and Wafer in any manufacturing process of integrated circuits (ICs) and impact the final yield of IC chips. To ensure a high yield, defect inspection of Mask and Wafer has been broadly adopted for monitoring many processes in high volume manufacturing (HVM) and shortening development cycle-times of critical processes in R&D. In HVM optical inspection tools have played a major role, and in R&D e-beam inspection tools have been a critical role. For the 7nm technology node and beyond, minimum size killer defects are going to be invisible for optical inspection tools, and e-beam inspection tools are too slow to capture smaller killer defects in an acceptable throughput. Accordingly, enhancing e-beam inspection tools in throughput has become an issue demanding prompt attention, and one promising solution is multi-beam inspection (MBI) technology. We are developing a MBI tool, which combines our cutting edge technologies in multi-beam electron optics, sample stage, scanning strategy and computational architecture. In this paper we will introduce MBI technology and development progress of our MBI tool, and will discuss future application of MBI technology.