System for high resolution imaging and measurement of topographic and material features on a specimen

A particle beam apparatus for charge-free high-resolution imaging and measurement of topographic and material features on a specimen, the particle beam apparatus comprising:

• (a) a particle source for providing a primary beam along a primary beam axis, said primary beam impinging on the specimen so as to release electrons therefrom, said electrons including secondary electrons and backscattered electrons;
• (b) an objective lens for focussing said electrons so as to provide a radial dispersion of said electrons relative to said primary beam axis, said radial dispersion of electrons including an inner annulus of backscattered electrons and an outer annulus of secondary electrons;
• (c) a backscattered electron detector for detecting said inner annulus of backscattered electrons, said backscattered electron detector being located between said particle source and said objective lens;
• (d) a secondary electron detector for detecting said outer annulus of secondary electrons, said secondary electron detector being located between said particle source and said objective lens;
• and
• (e) an evacuated chamber for housing the specimen.