InSb/In1− x Al x Sb strained-layer superlattices grown by magnetron sputter epitaxy

The growth of strained-layer superlattices of InSb/In0.6Al0.4Sb prepared by magnetron sputter epitaxy is reported for the first time. Individually controlled magnetron sputter sources of InSb, Al, and Sb were used to deposit 20-period superlattices with periods ranging from 76 –154 Å. Layer thicknesses determined from x-ray and cross-sectional transmission electron microscopy (TEM) analysis were in close agreement with those predicted on the basis of the growth-rate/deposition-time product, indicating a high degree of deposition control. X-ray and electron-channeling patterns showed excellent crystallinity. The absence of surface features in the InSb cap layer indicated the layers to be under tensile stress due to the 2.1% lattice mismatch between InSb and InSb/In0.6Al0.4Sb.