Growth of gallium antimonide (GaSb) by metalorganic chemical vapour deposition

Abstract

Growth of unintentionally doped GaSb by atmospheric pressure MOCVD using Trimethylgallium (TMGa) and Trimethylantimonide (TMSb) on various substrate is investigated. Optimum growth temperature and the V/III ratio window is given with respect to hole density, mobility and optical properties. The optimum growth rate was found to be 2.2 /spl mu/m/h with good surface morphology for samples grown at 500-540/spl deg/C and V/III ratio approximately equal to unity. The as grown samples are p-type, having room-temperature mobility and hole density at the optimum growth condition as above, of 500 cm/sup 2/ V/sup -1/ s/sup -1/ and 0.5-3.0/spl times/10/sup 17/ cm/sup -3/, respectively. The fundamental absorption band edge of grown layers in transmission spectra shows clear excitonic features at low temperatures. Very short growth time leads to quantum dot formation with the best quantum dots grown on Ge.