Structural, electrical, and optical properties of InAs_xSb_1-x epitaxial films grown by liquid-phase epitaxy

The InAs_xSb_1-x films were grown on (100) GaSb substrates by liquid-phase epitaxy, and their structural, electrical, and optical properties were investigated. The high-resolution x-ray diffraction results reveal that the single crystalline InAs_xSb_1-x films with a midrange composition are epitaxially grown on the GaSb substrates. Temperature dependence of the Hall mobility was theoretically modeled by considering several predominant scattering mechanisms. The results indicate that ionized impurity and dislocation scatterings dominate at low temperatures, while polar optical phonon scattering is important at room temperature (RT). Furthermore, the InAs_xSb_1-x films with the higher As composition exhibit the better crystalline quality and the higher mobility. The InAs_0.35Sb_0.65 film exhibits a Hall mobility of 4.62×10⁴ cm² V^-1 s^-1. The cutoff wavelength of photoresponse is extended to about 12 μm with a maximum responsivity of 0.21 V/W at RT, showing great potential for RT long-wavelength infrared detection.