High quality InAs0.04Sb0.96/GaAs single crystals with a cutoff wavelength of 12 μm grown by melt epitaxy

摘要

The InAs0.04Sb0.96 epilayers with a cutoff wavelength of 12 μm were successfully grown on semi-insulating (100) GaAs substrates using melt epitaxy (ME). Fourier transform infrared (FTIR) transmission spectra reveal a strongly band gap narrowing for this alloy. A room-temperature band gap of 0.1055 eV is demonstrated via analyzing the temperature dependence of the carrier density for the InAs0.04Sb0.96 layers, which is in good agreement with the value obtained by transmittance measurements. The temperature dependence of energy band gap for InAs0.04Sb0.96/GaAs is studied between 12 K and 300 K by measuring the absorption spectra. An electron mobility of 44,700 cm2/Vs with a carrier density of 8.77 ?1015 cm-3 at 300 K, an electron mobility of 21,500 cm2/Vs with a carrier density of 1.57 ?1015 cm-3 at 77 K, and a peak electron mobility of 48,000 cm2/Vs at 245 K have been achieved for a 100 μm thick epilayer. These results indicate its potential applications for infrared photodetectors and high-speed electron devices.