Newly developed mask observation scanning electron microscope (SEM) JWS-7800

Scanning electron microscopes (SEMs) are now coming into use as mask observation, metrology and defect inspection tools. Phase shift masks and X-ray masks are fabricated with several thin membranes on a substrate. In order to get 3D information about the membranes' structure, high tilt observation with high resolution is necessary. This paper describes a newly developed mask observation SEM (JWS-7800) which is intended for observation of various types of masks with high resolution, 10 nm at 1 kV acceleration, even at 60 degree(s) tilt angle.