Patent ID: 8193493
Filing Date: 2012-06-05
Classification: G01N,H01J

Abstract:
1. A multi-beam type electron beam inspection apparatus comprising: a primary optical system that separates a plurality of primary electron beams of a radiated electron beam from an electron source, and scans the plurality of primary electron beams on a sample: a detection system that detects secondary electron beams by the scanning of the plurality of primary electron beams, and outputs the detected secondary electron beams; a secondary optical system that directs the secondary electron beams corresponding to the plurality of primary electron beams to the detection system; a sample stage to move the sample table; and a control unit to control the primary optical system, the detection system, the secondary optical system, and the sample stage, wherein the control unit selects a number of the primary electron beams to irradiate the sample on the basis of the electric field intensity on the sample surface.