A high-resolution cathodoluminescence analysis system

Abstract

An efficient system for the collection and analysis of cathodoluminescence (CL) excited by the electron beam of a scanning electron microscope has been developed, employing an ellipsoidal mirror with its major axis parallel to the beam direction, 45 degrees plane mirror, fibre optic light guide and grating spectrometer. The optical transfer efficiency from sample to detector is 5% at 500 nm. Spectra from areas a few micrometres across can be recorded using beam currents as low as 1 nA with a spectral resolution of 1 nm. Monochromatic CL micrographs can be displayed on the screen. Some applications of the instrument in the field of compound semiconductors are illustrated.