InAs/GaSb II类超晶格探测器是近年来国际上发展迅速的红外探测器,其优越性表现在高量子效率和高工作温度,以及良好的均匀性和较低的暗电流密度,因而受到广泛关注。报道了InAs/GaSb超晶格中波材料的分子束外延生长和器件性能。通过优化分子束外延生长工艺,包括生长温度和快门顺序等,获得了具原子级表面平整的中波InAs/GaSb超晶格材料,X射线衍射零级峰的双晶半峰宽为28.8,晶格失配a/a=1.510-4。研制的p?鄄i?鄄n单元探测器在77 K温度下电流响应率达到0.48 A/W,黑体探测率为4.541010 cmHz1/2W,峰值探测率达到1.751011 cmHz1/2W。
Infrared(IR) photo detectors based on InAs/GaSb type II superlattice have developed quickly in recent years.Many groups show great interest in InAs/GaSb superlattice detector for its superiors as high quantum efficient,high working temperature,high uniformity and low dark current densities.The growth of mid-wavelength infrared InAs/GaSb superlattice on GaSb substrates by molecular beam epitaxy(MBE) was studied.The growth temperature and the interface structures to obtain high quality material were optimized.The InAs/GaSb superlattice layers were characterized by atomic force microscope(AFM) and high resolution X-ray diffraction(XRD).Finally,highly lattice matched mid-infrared InAs/GaSb superlattice material was achieved.The FWHM of the 0th satellite peak of X-ray scanning curve is 28.8 arcsec.The p-i-n single IR photodiode based on InAs/GaSb superlattice has current responsivity of 0.48 A/W and blackbody detectivity of 4.54×1010 cmHz1/2W,and peak detectivity of 1.75×1011 cmHz1/2W at 77 K.