The preparation of epitaxial InSb films by magnetron sputtering

Abstract

InSb, with its narrow bandgap, has found application in a wide variety of infrared detector applications, ranging from infrared astronomy on the Galileo satellite to tactical weapon guidance systems. However, InSb also demonstrates an extremely high electron mobility, up to 1 000 000 cm2∙V−1∙s−1 at 77 K, which makes it of particular interest for very high-speed circuit applications. In the past, most multilayer InSb structures have been prepared by conventional crystal-growth techniques, including liquid-phase epitaxy, metalorganic chemical vapour deposition, and molecular-beam epitaxy. In this presentation, the preparation of thin epitaxial films of InSb by magnetron sputtering will be discussed. Using this technique, we have deposited good quality epitaxial InSb films on [Formula: see text] InSb and [Formula: see text] GaAs. In this study, the effects of substrate temperature and sputter pressure on film morphology, composition, and growth rate are examined. As well, preliminary measurement of the electrical characteristics of these layers and their crystal quality as determined by X-ray diffraction and large-area electron-channelling pattern analysis are presented.