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

• Published in: Journal of crystal growth 2018-05, Vol.490, p.97-103
• Main Authors: Jia, Bo Wen, Tan, Kian Hua, Loke, Wan Khai, Wicaksono, Satrio, Yoon, Soon Fatt
• Format: Article
• Language: English
• Subjects: A3. Molecular beam epitaxy; B1. Antimonides; B2. Semiconducting III-V materials; B3. Infrared devices; Blackbody; Buffers; Dislocation density; Electron mobility; Epitaxial growth; Gallium antimonides; Indium antimonide; Intermetallic compounds; Molecular beam epitaxy; Molecular beams; Molecular chains; Semiconductors; Silicon substrates; Thermography; Threading dislocations
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2018.03.026

•Relaxed InSb was grown on Si by MBE via an AlSb/GaSb buffer.•Interfacial misfit dislocations accommodated lattice mismatch.•Si delta doping decreased the density of threading dislocation in the GaSb on Si.•A 300 K electron mobility of 22,300 cm2/Vs exhibited in a 0.8 µm InSb on Si.•InSb photoconductor demonstrated a photoconductive gain in mid-infrared region. 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.