spectrometer, method for spectroscopic analysis and method for combined topographic and spectroscopic study of a surface

摘要

A combined surface topography and spectroscopic analysis instrument comprises a scanning tunnelling microscope tip (12); and a sample carrier (58) which supports a sample (10) so that a surface thereto to be analyzed is presented towards the tip (12). The sample carrier (58) and the tip (12) are relative movable to enable the distance between the tip (12) and the surface to be varied in use and the sample surface to be scanned in two dimensions by the tip (12). An electronic analyzer is positioned to detect electrons from the tip (12) which have been back-scattered off the sample surface. A voltage controller (59) enables selective operation of the tip (12) in a first voltage range in scanning tunnelling mode, to enable spatial resolution imaging of the sample surface, and in a second, higher, voltage range in electron field emission mode whereby to permit the electron analyzer to analyze the back-scattered electrons. The electron analyzer is positioned so as to detect back-scattered electrons travelling at an angle of less than 20° with respect to the sample surface.