TITLE:
Growth Optimization, Strain Compensation and Structure Design of InAs/GaSb Type-II Superlattices for Mid-Infrared Imaging
AUTHORS:
Yuxin Song, Shumin Wang, Carl Asplund, Rickard Marcks von Würtemberg, Hedda Malm, Amir Karim, Xiang Lu, Jun Shao
KEYWORDS:
InAs/GaSb; Type-II Superlattce; Molecular Beam Epitaxy; Strain Compensation
JOURNAL NAME:
Crystal Structure Theory and Applications,
Vol.2 No.2,
June
19,
2013
ABSTRACT: InAs/GaSb type-II superlattce (T2SL) photodetector structures at the MWIR regime were grown by molecular beam epitaxy. The growth temperature and group-V soaking times were optimized with respect to interface and transport quality. Novel strain compensation schemes with insertion of InSb layers were proposed and tested to be efficient to tune the overall strain between tensile and compressive without degradation of interface and optical quality. The effect of the proposed methods is modeled by analytic functions. Band structure calculations were also carried out for the proposed T2SL structures to assist optimizing sample designs. Single pixel photodiodes with a low dark current were demonstrated.