Multiple beam inspection (MBI) for 7nm node and beyond: technologies and applications

EUV lithography has been adopted in most advanced semiconductor manufacture fabs, enabling the next step in design rule scaling. With this progress, minimum critical defect size has become smaller and harder to detect. Defect inspection equipment suppliers must therefore in parallel provide a significant step up in inspection sensitivity at a reasonable throughput. Optical inspection tools are facing an unprecedented challenge because defects less than 10nm are not optically visible. As an alternative, semiconductor manufacturers have turned toward e-beam inspection. E-beam inspection is widely used in R&D to shorten development cycle-time and selectively used in high volume manufacturing (HVM) for process monitoring, however currently it is not fast enough for large-scale replacement of optical inspection. Our approach to address this shortcoming is to combine cutting edge multiple-beam technology with a cutting edge positioning system/computation architecture to create a next generation e-beam inspection system capable of scanning with multiple electron beams at the same time. This paper reports on the progress in developing such a system as well as future multi-beam inspection applications.