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Cathodoluminescence Study Of Defects In Iii-V Substrates And Structures, M. Cocito, P. Franzosi, G. Salviati, F. Taiariol

Scanning Electron Microscopy

Solid state detector cathodoluminescence studies of semiconducting and semi-insulating GaAs and InP crystals, were performed. The origin of the dislocation contrast in GaAs:Si doped substrates, in the carrier concentration range from 10¹⁶ to 6 · 10¹⁸ cm^-3, were discussed. The image contrast was explained on the basis of the emission efficiency versus carrier concentration curve, obtained in the transmission mode. Single dislocations and dislocation arrangements in addition to growth striations, clusters and precipitate-like microdefects were evidenced. The above mentioned microdefects were detected in GaAs: Te, S and Si doped and InP: Sn doped specimens. Commercial InP:Sn …

A High Efficiency Cathodoluminescence System And Its Application To Optical Materials, A. D. Trigg

Scanning Electron Microscopy

A high collection efficiency spectroscopic cathodoluminescence (CL) system based on an in-line ellipsoidal mirror has been constructed for use on a Cambridge S250 scanning electron microscope (SEM). It can be fitted to or removed from the SEM in about 30 minutes and requires no significant modification of the instrument. It can be used to obtain total CL images, monochromatic CL images or CL spectra with an ultimate spectral resolution of 1 nm.

The system has been applied to the study of doped synthetic quartz crystals, optical fibres and optical fibre preforms, and to yttrium aluminium garnet, bismuth silicon oxide and …

The Cathodoluminescence Mode Of The Scanning Electron Microscope: A Powerful Microcharacterization Technique, D. B. Holt, F. M. Saba

Scanning Electron Microscopy

By detecting cathodoluminescence (CL) in a scanning electron microscope (SEM), pan and monochromatic micrographs and CL spectral analyses analogous to x-ray mode point analyses can be obtained. Complete microcharacterization requires alternate examination of both micrographs and spectra. New techniques for near infra-red CL and low-temperatures to produce sharp spectra are of increasing importance. CL emission is due to electron transitions between quantum mechanical states so the radiative defects present can be unambiguously identified at liquid helium temperatures. Strongly luminescent impurities can be detected to below one part in 10⁸. This is 10⁴ times as sensitive as the …