2～5μm InAs/GaSb超晶格红外探测器

2-5 μm InAs/GaSb superlattices infrared photodetector

采用分子束外延方法在GaSb和GaAs衬底上生长了不同周期厚度的InAs／GaSb高质量II型能带结构超晶格红外探测器，其探测波长覆盖2～5μm红外波段。采用高分辨透射电子显微镜、原子力显微镜、X射线衍射测试、室温与低温光电流响应谱及室温与低温光荧光谱等多种测试手段检验了分子束外延生长在不同衬底上的超晶格材料质量与光学质量。该材料用于制造2～5μmGaAs基与GaSb基InAs／GaSb超晶格红外探测器。在77K温度下，2μm波段GaAs基InAs／GaSb超晶格红外探测器探测率为4×10^9cm·Hz^1/2／w，5μm波段GaSb基InAs／GaSb超晶格红外探测器探测率为1．6×10^100cm·Hz^1／2／W。

High quality InAs/GaSb type-II band alignment superlattices infrared photodetectors with different InAs thicknesses were grown on GaSb and GaAs substrates by molecular beam epitaxy （MBE）. The detection wavelengths of these InAs/GaSb SLs infrared detectors were 2-5 μm. The material and optical qualities of InAs/ GaSb superlattices on different substrates by MBE were characterized by different measurement methods, including high resolution transmission electron microscope （HRTEM）, atomic force microscope （AFM）, X-ray diffraction （XRD）, low temperature （LT） and room temperature （RT） photo response spectrum and LT and RT photoluminescence （PL） spectrum. Then 2-5 μm GaAs and GaSb based infrared photodetectors were fabricated by these InAs/GaSb type-II band alignment superlattices materials. The detectivity of the 2 μm GaAs based InAs/GaSb SLs photodetector is 4×10^9cm·Hz^1/2/W at 77K and that of the 5 μm GaSb based InAs/GaSb SLs photodetector is 1.6×10^9cm·Hz^1/2/W at the same temperature.