The growth of GaSb/Al0.33Ga0.67Sb MQW on n-Silicon (100) with Al0.66Ga0.34Sb/AlSb SPS layers

Abstract

GaSb/Al0.33Ga0.67Sb multi-quantum well (MQW) film on n-Si (1 0 0) substrates is grown by molecular beam epitaxy. The effects of a miscut angle of the Si substrate (0 degrees, 5 degrees, and 7 degrees) on the properties of an AlSb layer were also studied. The suppression of the anti-phase domains (APD) was observed at a miscut angle of 5 on Si (1 0 0). It was found that the growth temperature in the range of 510-670 degrees C affects the quality of AlSb layers on Si. Low root-mean-square surface (RMS) roughness values of 3-5 nm were measured by atomic force microscopy at growth temperatures ranging from 550 degrees C to 630 degrees C. In addition, Al0.66Ga0.34Sb/AlSb short period superlattice (SPS) layers were used to overcome problems associated with a large lattice mismatch. The RMS values of samples with a SPS were partially measured at approximately similar to 1 nm, showing a larger APD surface area than samples without a SPS layer. Bright-field cross-sectional transmission electron microscopy images of the GaSb/Al0.33Ga0.67Sb MQW, the AlSb buffer layer and the Al0.06Ga0.34Sb/AlSb SPS layers show that numerous twins from the AlSb/Si interface were removed by the AlSb buffer layer and the Al0.66Ca0.34Sb/AlSb SPS. The GaSb/Al0.33Ga0.67Sb MQW PL spectra were obtained at 300 K and 10 K with a fixed excitation power of 103 mW. Emission peaks appeared at 1758 nm and 1620 nm, respectively. (C) 2014 Elsevier Ltd. All rights reserved.