Growth and characterization of an InSb infrared photoconductor on Si via an AlSb/GaSb buffer

• Main Authors: Jia, Bo Wen, Tan, Kian Hua, Loke, Wan Khai, Wicaksono, Satrio, Yoon, Soon Fatt
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2019
• Subjects: Molecular beam epitaxy; Antimonides; DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/104687; http://hdl.handle.net/10220/50025
• Institution: Nanyang Technological University

A 99.6% relaxed InSb layer is grown on a 6° offcut (1 0 0) Si substrate via an AlSb/GaSb buffer using molecular beam epitaxy (MBE). A 200 nm GaSb buffer is first grown on Si and the lattice mismatch between them is accommodated by an interfacial misfit (IMF) array consisting of uniformly distributed 90° misfit dislocations. Si delta doping is introduced during the growth of GaSb to reduce the density of threading dislocation. Subsequently, a 50 nm AlSb buffer is grown followed by a 0.8 µm InSb layer. The InSb layer exhibits a 300 K electron mobility of 22,300 cm2/Vs. An InSb photoconductor on Si is demonstrated with a photoconductive gain from 77 K to 200 K under a 700 °C maintained blackbody.