High Lattice Match Growth of InAsSb Based Materials by Molecular Beam Epitaxy

High lattice match growth of InAsSb based materials on GaSb substrates is demonstrated. The present results indicate that a stable substrate temperature and the optimal flux ratios are of critical importance in achieving a homogeneous InAsSb based material composition throughout the growth period. The quality of these epilayers is assessed using a high-resolution x-ray diffraction and atomic force microscope. The mismatch between the GaSb substrate and InAsSb alloy achieves almost zero, and the rms surface roughness of InAsSb alloy achieves around 1.7 ? over an area of 28 μm \times 28 μm. At the same time, the mismatches between GaSb and InAs/InAs_0.73Sb_0.27 superlattices (SLs) achieve approximately 100 arcsec (75 periods) and zero (300 periods), with the surface rms roughnesses of InAs/InAs_0.73Sb_0.27 SLs around 1.8 ? (75 periods) and 2.1 ? (300 periods) over an area of 20 μm\times20 μm, respectively. After fabrication and characterization of the devices, the dynamic resistance of the n-barrier-n InAsSb photodetector near zero bias is of the order of 10^6 \Omega\cdotcm^2. At 77 K, the positive-intrinsic-negative photodetectors are demonstrated in InAsSb and InAs/InAsSb SL (75 periods) materials, exhibiting fifty-percent cutoff wavelengths of 3.8 μm and 5.1 μm, respectively.