MOMBE GROWTH OF INGAP ON (100) AND (411)A GAAS SUBSTRATES USING TERTIARYBUTYLPHOSPHINE (TBP)

InGaP epi-layers were grown on (1 0 0) and (4 1 1)A oriented GaAs subs trates. Ga composition control of In1-xGaxP was achieved for both (1 0 0) and (4 1 1)A substrates. Epi-layers grown on (4 1 1)A GaAs showed about 10% less In incorporation than those on (1 0 O) GaAs substrates. A fairly wide range of carrier concentration from 1.1 x 10(17) to 3.8 x 10(19) cm(-3) was obtained for carbon-doped and silicon-doped sampl es. Electrical properties of the samples grown on (1 0 0) and (4 1 1)A were about the same for both silicon and carbon doping. The electron concentration became saturated at 1019 cm-3 and the mobility decreased drastically for the samples grown on (1 0 0), however electron concen trations over 10(19) cm(-3) were achieved and mobilities remained over 100 cm(2)/V s for samples grown on (4 1 1)A. Moreover, silicon-doped n-type InGaP on (4 1 1)A GaAs substrate was observed to be flatter tha n the layers on (1 0 0), although the doping level was higher. (C) 199 8 Elsevier Science B.V. All rights reserved.