New routes to metal-organic precursors; growth of high purity AIGaAs by CBE using a novel amine adduct of triisopropylgallium


  • The authors are pleased to acknowledge continued technical assistance from D. E. J. Soley, P. K. Moores, V. Stirnson and L. Smith (DRA, Malvern).


High-purity AlGaAs has been grown using chemical beam epitaxy employing a new gallium precursor, triisopropylgallium·NEt3 in combination with AlH3(NMe2Et). The materials exhibit low oxygen concentrations and excellent optical and electrical characteristics, comparable with the best materials grown using molecular beam epitaxy or metal-organic vapor phase epitaxy. The use of amine solvents and the complete absence of eters from the precursors has important consequences for the growth of III–V alloys by CBE, as oxygen-containing solvents are known to lead to materials degradation.