High-quality InSb growth by metalorganic vapor phase epitaxy

We have investigated the electron transport properties and crystallinity of InSb films deposited on GaAs substrates. The films were grown by metalorganic vapor phase epitaxy with trimethylindium and trisdimethylaminoantimony as In and Sb sources. Using a two-step growth method and investigating growth conditions extensively, we found that the electron mobility of films either 1.0 or 1.5 mu m thick strongly depended on the temperature at which the first layer (25 nm thick) was grown. The highest mobility, 61,200 cm(2) V-1 s(-1), was obtained at growth temperature of 260 degrees C and the smallest full-width at half-maximum (FWHM) of the X-ray deflection rocking curve, 205 arcsec, was obtained at 320 degrees C. These mobility and FWHM values, both of which are for a total lnSb thickness of 1.5 mu m, are superior to those of InSb films grown by molecular beam epitaxy. Secondary ion mass spectrometry measurements showed that below 340 degrees C the carbon impurity concentration increased drastically with decreasing growth temperature. This carbon incorporated InSb indicated p-type behavior at low temperature by Hall measurement. These results suggest that high concentrations of carbon impurities compensated the extrinsic electrons generated from InSb/GaAs interfacial dislocations. (C) 2014 Elsevier B.V. All rights reserved.