InAs/GaSb超晶格中波焦平面材料的分子束外延技术

Mid-wavelength infrared InAs/GaSb superlattice grown by molecular beam epitaxy

报道了InAs/GaSb超晶格中波材料的分子束外延生长技术研究.通过改变GaSb衬底上分子束外延InAs/GaSb超晶格材料的衬底温度,以及界面的优化等,改善超晶格材料的表面形貌和晶格失配,获得了晶格失配Δa/a=1.5×10-4,原子级平整表面的InAs/GaSb超晶格材料,材料77 K截止波长为4.87μm.

The growth of mid-wavelength infrared InAs/GaSb superlattice on GaSb substrates by molecular beam epitaxy（MBE）was studied.We optimized the substrate temperature and interface structures to obtain high quality material.The InAs/GaSb superlattice layers were characterized by Atomic Force Microscope（AFM）,high resolution X-ray diffraction（XRD） and Fourier Transform Infrared Spectrum.We found the optimal substrate temperature for GaSb and superlattice is 485℃ and 450℃ respectively.We finally obtained highly lattice matched InAs/GaSb materials with 50% cut-off wavelength at 4.84 μm at 77 K.