INVESTIGATIONS ON DOMAIN BOUNDARIES IN ORDERED GAINP USING STEREO TRANSMISSION ELECTRON-MICROSCOPY

CuPtB-type ordered GaInP, lattice matched to GaAs, has been grown by m etal organic vapor phase epitaxy. Ordered domains and their boundaries are investigated by dark-field transmission electron microscopy. By m eans of stereo images, we are able to show that domain boundaries are microscopically thin. The fact that they generally appear as broad dar k lines in dark-field images is due to the projection onto the image p lane and does not mean that there is a disordered alloy surrounding or dered domains. This is in agreement with photoluminescence excitation spectra of ordered samples which do not show any sign of a disordered phase. (C) 1997 Academic Press Limited.