The growth of InSb using alternative organometallic Sb sources

Abstract

The growth of InSb was investigated using triisopropylantimony (TIPSb) or tertiarybutyldimethylantimony (TBDMSb) and trimethylindium (TMIn) or triethylindium (TEIn) over a temperature range of 350 to 475°C and pressures between 200 and 660 Torr. The growth rates of InSb using TMIn or TEIn and either TIPSb or TBDMSb at temperatures ≤ 425°C were proportional to both the TMIn or TEIn flow rate and the temperature. The surface morphology of InSb grown using either TIPSb or TBDMSb and TMIn or TEIn was very rough for growth temperatures ≤ 425°C. The InSb with the highest mobility was grown at 400°C and a V/III ratio of 3 using TIPSb and TMIn. It was n-type with a carrier concentration of 2.5 × 10 15 cm −3 and a mobility of 78,160 cm 2/V s at 77 K. Both n- and p-type InSb were grown using TBDMSb with mobilities up to 67,530 and 7773 cm 2/V s respectively, at 77 K. Only p-type InSb could be grown using TEIn and TIPSb. The mobility for InSb using either TIPSb or TBDMSb and TMIn was optimized by reducing temperatures, pressures and V/III ratios. The opposite was true for surface morphology, which improved with higher temperature, pressure, and V/III ratio. The growth of high mobility InSb with smooth surfaces at T ≤ 425°C was not achieved with TIPSb or TBDMSb and TMIn or TEIn for the growth conditions examined in this investigation.