Analysis of Backscattered Electron Signals in X-Ray Mask Inspection

Abstract

The backscattered electron signals from X-ray masks are studied by a Monte Carlo simulation of electron scattering. 0.1 µm Au double steps on a Si substrate are chosen as sample structures of the X-ray mask. Two types of simple defect structures are assumed and the variations of the backscattered electron signals due to these defects are analyzed. Incident energy and detection angle dependences of the backscattered electron signals are studied by the simulation in order to discuss the optimum conditions required to inspect the X-ray masks precisely and efficiently.