Group III hydride precursors for the metalorganic vapour phase epitaxy (MOVPE) of (AlGa)As/GaAs heterostructures

Abstract

The Group III hydride compounds trimethylamine alane (AlH 3·N(CH 3) 3 (TMAAl)) and dimethylamine gallane (GaH 3· N(CH 3) 2H (DMAGa)) have been synthesized and used successfully for the growth of GaAs and (AlGa)As bulk epitaxial layers and (AlGa)As/GaAs heterostructures by low-pressure metalorganic vapour phase epitaxy (LP-MOVPE) in combination with both AsH 3 and the AsH 3 substitute tertiarybutyl arsine (TBAs). Uncompensated, n-type GaAs layers (1.4×10 16 cm -3, 14800 cm 2/V·s at 77 K) are realized using at present not specifically purified DMAGa in combination with both AsH 3 as well as TBAs. X-ray diffraction linewidths of below 20 arc sec (FWHM) for the superlattice (SL) satellite peak of AlAs/GaAs SL are indicative of high crystalline quality and monolayer abrupt heterointerfaces. These results are supported by luminescence investigations of GaAs and (AlGa)As as well as of (AlGa)As/GaAs single quantum well heterostructures (SQWHs) with well widths down to 1.5 nm.