QUALITY OF ALAS-LIKE AND INSB-LIKE INTERFACES IN INAS ALSB SUPERLATTICES - AN OPTICAL STUDY/

Two short-period InAs/AlSb superlattices, grown with an AlAs-like inte rface and an InSb-like interface, respectively, were studied with Rama n spectroscopy, x-ray diffraction, and ellipsometry. Our measurements show that the InSb-like interface grows perfectly pseudomorphically, w hereas the sample with the AlAs-like interface shows indications of re laxation and As interdiffusion. This different interface quality seems to be a fundamental problem, rather than the result of the growth tec hnique.