Observation of cathodoluminescence at single dislocations by STEM

Abstract

A cathodoluminescence detector on a V.G. Microscopes HB5 STEM has been used to form high-resolution cathodoluminescence images of single dislocations in natural type-IIb diamond. The cartridge and light-collection systems are described and stray-electron effects are discussed. The cathodoluminescence and transmitted-electron signals are obtained simultaneously, which allows the direct correlation of the cathodoluminescence image with the transmitted-electron image. Almost all the luminescence was emitted from dislocations, but not all dislocations were luminescent. Examples of both 60° and screw dislocations were found to be luminescent, and both types were also seen to be non-luminescent.