ELSEYIER Surface Science 338 (1995) 204-210 Epitaxial growth of GaSb(l11) on Sb(l11) by interdiffusion assisted molecular beam epitaxy J.-L. Guyaux a, R. Sporken aT * , R. Caudano a, V. Wagner b, J. Geurts b, N. Esser ‘, W. Richter ’ a Laboratoire Interdisciplinaire de Spectroscopic Electronique, Facult& Universitaires Notre-Dame de la Pair, 61 rue de Bruxelles, B-5000 Namur, Belgium b RWTH Aachen, I. Physikalisches Institut, Sommerfeldstrasse 16, Turm 28, D-52074 Aachen, Germany ’ Berlin University of Technology, Institutjiir Festtirperphysik, Sekr. PN6-I, Hardenbergstrasse 36, D-10623 Berlin, Germany Received 2 January 1995 accepted for publication 29 April 1995 Abstract GaSb has been grown epitaxially on Sb(ll1) substrates. Epitaxial growth occurs due to the interdiffkion when gallium is evaporated onto heated Sb substrates. We have studied the influence of the substrate temperature and of the gallium flux on the interdiffusion and the resulting layer quality and stoichiometry by reflection high energy electron diffraction (RHEED), X-ray photoelectron spectroscopy (XPS) an: Raman spectroscopy. The best layers were obtained at a substrate temperature of about 300°C and a growth rate of 0.25 A s-l. Keywords: Antimony, Epitaxy, Gallium, Gallium antimonide, Raman scattering spectroscopy, Reflection high-energy electron diffraction (RHEED), Semiconductor-semimetal interfaces, Surface structure, X-ray photoelectron spectroscopy 1. Introduction Heterostructures combining a semiconductor with a semimetal have received far less attention in the past than heterostructures between semiconductors alone, although novel device applications may be expected. Recently, Golding et al. [l] suggested that Sb/GaSb semimetal-semiconductor superlattices should have unique properties. When the Sb film thickness is small, quantisation of the carrier motion in the z direction occurs. By sandwiching the layers l Corresponding author. E-mail: robert.sporken@fundp.ac.be. between layers of a semiconductor with a suitable potential barrier, quantum confinement is expected to push the conduction band of the Sb up, while the valence band moves down. At some point, the two bands will cross and the bandstructure of an indirect narrow band gap semiconductor results. One then expects Auger recombination lifetimes much longer than for semiconductors with a similar but direct band gap, as well as low optical absorption coeffi- cients. This would make this material highly attrac- tive for optical devices operating in the infrared [I]. However, for such devices, it is essential that the crystal structure of the semiconductor be compatible with the semimetal. We will show that this is the case for GaSb/Sb heterostructures. 0039-6028/95/$09.50 0 1995 Elsevier Science B.V. All rights reserved SSDI 0039-6028(95)00593-5