CHARACTERISTICS OF CARBON-DOPED INGAAS USING CARBONTETRABROMIDE BY METALORGANIC MOLECULAR-BEAM EPITAXY

Carbon-doped In0.53Ga0.47As structures have been grown on InP by metalorganic molecular beam epitaxy using carbontetrabromide as the dopant source. Hall, secondary ion mass spectrometry (SIMS) and X-ray measurements were done to characterize the material. Doping levels from 2 X 10(17) to 7 X 10(19) cm(-3) were measured with mobilities ranging from 100 to 45 cm(2)/V.s. SIMS data show very abrupt doping profiles with no apparent memory effects. Hydrogen was measured in the C doped regions, however, no passivation effects were observed and Hall and SIMS data agreed within experimental error. Post-growth anneals of the highest doped samples showed no change in carrier concentration. The incorporation of C showed a strong dependence on the group V beam flux (concentration similar to flow-(3/4)). We believe that this is related to the change in group V vacancy concentration as the group V beam flux is varied. A smaller dependence of C incorporation was also observed with the growth temperature.