摘要
报道了50%截止波长为12.5μm的InAs/GaSb Ⅱ类超晶格长波红外探测器材料及单元器件.实验采用分子束外延技术在GaSb衬底上生长超晶格材料.吸收区结构为15ML(InAs)/7ML(GaSb),器件采用PBIN的多层异质结构以抑制长波器件暗电流.在77K温度下测试了单元器件的电流-电压(Ⅰ-Ⅴ)特性,响应光谱和黑体响应.在该温度下,光敏元大小为100μm×100μm的单元探测器RmaxA为2.5Ωcm2,器件的电流响应率为1.29A/W,黑体响应率为2.1×109cmHz1/2/W,11μm处量子效率为14.3%.采用四种暗电流机制对器件反向偏压下的暗电流密度曲线进行了拟合分析,结果表明起主导作用的暗电流机制为产生复合电流.
A 12.5μm long wavelength infrared detector based on InAs/GaSb Type-II superlattice was presented in this work. Superlattice materials were grown on GaSb substrates using MBE technology. Absorber structure for long wave- length detector was designed to be 15ML（InAs）/7ML （GaSb）. The detector used a PBIN multiple heterostructures to decrease the dark current. The dark current 1-V curve, responsivity spectra and blackbody current responsivity were measured at 77 K. At this temperature, RmaxA product was 2.5 Ωcm2 for the device with a photo sensitive area of 100μm × 100μm. At zero bias, a current responsivity of 1.29 A/W was measured for the detector, which correspond to a blackbody detectivity of 2.1 × 109 cmHzl/2/W. Quantum efficiency at 11 μm was measured to be 14.3%. Dark current characteristics were simulated with four kinds of probable transport mechanisms. The results showed that the dominated dark current of the detector is Generation-Recombination current.
出处
《红外与毫米波学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第3期210-213,224,共5页
Journal of Infrared and Millimeter Waves
基金
国家自然科学基金(61176082)~~
