Research on short period InAs/GaSb superlattices photoconductors on GaAs substrates
GaAs基短周期InAs/GaSb超晶格红外探测器研究

Two type II superlattices (SLs): InAs(2ML)/GaSb(8ML) and InAs(8ML)/GaSb(8ML) were grown on GaAs substrates by molecular-beam epitaxy. High resolution X-ray diffraction showed the period of the two SLs was 33 and 56 . Room-temperature optical transmittance spectra showed clear absorption edge at ~2.1μm and ~5μm for the two SLs. The SWIR and MWIR photoconductor devices were fabricated by standard lithography and etched by tartaric acid solution. The 50% cutoff wavelength of the two photoconductors was 2.1μm and 5.0μm respectively. D*bb was above 5×108 cmHz1/2/W for two kinds of photoconductors at 77K. D*bb was 2×108 cmHz1/2/W for SWIR photoconductor at room temperature.