摘要
采用分子束外延技术在GaSb衬底上生长了PIN型长波红外28 ML InAs/7 ML InAs0.48Sb0.52超晶格探测器材料,研究了Sb浸润界面对其表面形貌、晶体结构和光电性能的影响。结果发现:相对于无界面控制的超晶格,采用Sb浸润界面的超晶格表面更平整,表面粗糙度仅为1.28;超晶格晶体结构更完整,界面起伏明显减小,与衬底的晶格失配度由3.26%减小到2.97%。InAs/InAsSb超晶格探测器的50%截止波长为10μm,量子效率为3.1%;Sb浸润界面的超晶格具有更低的暗电流和更高的微分阻抗,-50 mV偏压下暗电流密度为0.12 A/cm^ 2,零偏阻抗面积乘积(R 0A)为0.44Ω·cm^2,计算得到探测率为5.06×10^7 cm·Hz 1/2/W。Sb浸润界面有效抑制了Sb的扩散,提高了超晶格的晶体质量和探测性能,但失配应力依然很大。这些结果为高质量长波红外InAs/InAsSb超晶格的界面生长提供了依据。
PIN-type long-wave infrared(LWIR)28 ML InAs/7 ML InAs 0.48 Sb 0.52 superlattice detector materials were grown on GaSb substrates by mole-cular beam epitaxy(MBE).The influence Sb-soaked interface on the surface morphology,microstructure and photoelectric properties were studied.The results showed that,compared with superlattices without interface control,the surface of superlattices with Sb-soaked interface was smoother with the roughness 1.28.The crystal structure was more complete with the FWHM and interface fluctuations reducing significantly.The mismatch between superlattices and substrates was reduced from 3.26%to 2.97%.The 50%cut-off wavelength of InAs/InAsSb superlattice detector was 10μm with the quantum efficiency 3.1%.The superlattice with Sb-soaked interface had lower dark current and higher differential impedance.The dark current density was 0.12 A/cm^ 2 and R 0A was 0.44Ω·cm^ 2 at-50 mV bias.The detectivity was calculated to 5.06×10^7 cm·Hz 1/2/W.This indicated that Sb-soaked interface effectively inhibited the diffusion of Sb and improved the crystal quality and detection perfor-mance.But the mismatch stress caused by the interface was still very large.These results provided a basis for the interface growth of high-quality LWIR InAs/InAsSb superlattice detector.
作者
齐通通
郭杰
王国伟
郝瑞亭
徐应强
常发然
QI Tongtong;GUO Jie;WANG Guowei;HAO Ruiting;XU Yingqiang;CHANG Faran(Yunnan Key Laboratory for Opti-electronic Information Technology,Yunnan Normal University,Kunming 650092,China;State Key Laboratory for Superlattices and Microstructures,Institute of Semiconductors,CAS,Beijing 100083,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第S01期86-89,共4页
Materials Reports
基金
国家自然科学基金(61274137)。
