Abstract: A method of operating a charged particle beam device is disclosed, including focusing a charged particle beam onto a sample with an objective lens assembly; passing a reflected light beam through a bore of the objective lens assembly to an interferometer; and interferometrically determining a z-position of the sample with the interferometer. A charged particle beam device is disclosed, including a charged particle beam generator which has a charged particle source. A charged particle path for the charged particle beam extends through a bore of an objective lens assembly toward a sample stage. An interferometer is arranged to receive a reflected light beam which passes through the bore of the objective lens assembly.

Abstract: A method of operating a charged particle beam device is disclosed, including focusing a charged particle beam onto a sample with an objective lens assembly; passing a reflected light beam through a bore of the objective lens assembly to an interferometer; and interferometrically determining a z-position of the sample with the interferometer. A charged particle beam device is disclosed, including a charged particle beam generator which has a charged particle source. A charged particle path for the charged particle beam extends through a bore of an objective lens assembly toward a sample stage. An interferometer is arranged to receive a reflected light beam which passes through the bore of the objective lens assembly.

Abstract: A particle beam column for high-resolution imaging and measurement of topographic and material features on a specimen. The particle beam column includes a particle source for providing a primary beam along a primary beam axis for impinging on the specimen so as to release secondary electrons and backscattered electrons therefrom. The particle beam column also includes an objective lens for focussing the electrons so as to provide a radial dispersion of electrons relative to the primary beam axis, the radial dispersion of electrons including an inner annulus of backscattered electrons and an outer annulus of secondary electrons. The particle beam column still further includes a backscattered electron detector for detecting the inner annulus of backscattered electrons and a secondary electron detector for detecting the outer annulus of secondary electrons.

Abstract: An electron detector for use in particle beam apparatus, providing particularly high acceptance of backscattered electrons. The electron detector includes an electron multiplier for detecting electrons and an electrode deployed between the electron multiplier and a specimen. The electrode is biased at a negative potential with respect to the specimen and also with respect to the electron multiplier.