Molecular-beam epitaxial growth of high quality InSb for p-i-n photodetectors

We report the growth of high quality InSb p-i-n structures which have been optimized using reflection high energy electron diffraction. Optimized InSb p-i-n structures of 5.8 μm thickness demonstrated x-ray full widths at half-maximums (FWHMs) of 101 and 147 arcsec for GaAs and Si substrates, respectively, and exhibited excellent uniformity and morphology. Prototype InSb p-i-n detectors on Si have been fabricated and have demonstrated photovoltaic response at 6.5 μm up to 200 K. A 4.8 μm InSb layer grown on GaAs at a growth temperature of 395 °C and a III/V incorporation ratio of 1/1.2 had an x-ray rocking curve FWHM of 158 arcsec and a Hall mobility of 92 300 cm2 V−1 s−1 at 77 K.