SCANNING ELECTRON MICROSCOPE AND SECONDARY ELECTRON DETECTION METHOD

PROBLEM TO BE SOLVED: To make it possible to detect secondary electrons resulting from low angle reflected electrons or high angle reflected electrons while making discrimination with a simple construction.SOLUTION: A scanning electron microscope according to the present invention includes a specimen voltage source 36 and, when obtaining an observation image of a surface of a specimen 13, irradiates the specimen 13 with primary electron lines 2 by applying a positive electrode voltage (300 V, for instance) from the specimen voltage source 36 to the specimen 13. When doing so, secondary electrons 33 and reflected electrons 31 are emitted from the surface of the specimen 13 but the secondary electrons 33 are pulled back to the specimen 13 due to the applied positive electrode voltage and only the reflected electron 31 are substantially emitted from the specimen 13. Also, high angle reflected electrons 31a, out of the reflected electrons 31, pass through an object lens 12 and reach an upper part thereof. Accordingly, at a secondary electron detector 22, only the secondary electrons 32 emitted when low angle reflected electrons 31b collide with the object lens or the like, in other words, the secondary electrons 32 resulting from the low angle reflected electrons 31b are detected.