Optoelectronic Transport Properties of Nanostructured Multi-Quantum Well InAs/GaSb Type II LWIR and MWIR Detectors

• Published in: Journal of electronic materials 2022-12, Vol.51 (12), p.6835-6845
• Main Authors: Benaadad, Merieme, Nafidi, Abdelhakim, Melkoud, Samir, Barkissy, Driss, El Yakoubi, Essediq Youssef
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Cut off wavelength; Density of states; Electron transport; Electronics and Microelectronics; Energy; Energy gap; Gallium antimonides; Indium arsenides; Infrared detectors; Instrumentation; Investigations; Low temperature; Materials Science; Multi Quantum Wells; Optical and Electronic Materials; Optoelectronics; Original Research Article; Parameters; Sensors; Solid State Physics; Thickness; Transport properties; Valence band
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-022-09906-y

We report in this study the optoelectronic properties of mid- and long-wave infrared type II multiple quantum wells (MQWs) of InAs( d 1 )/GaSb( d 2 ) using our enhanced envelope function formalism at low temperature. We have investigated the band structure energy subbands and carrier effective mass m * / m 0 of the MQWs in the growth direction and in-plane. The relationship between semiconductor-to-semimetal (SC–SM) transition and well thickness d 1 were analyzed. Furthermore, we studied and interpreted the evolution of the photodetector parameters including fundamental band gap, corresponding cutoff wavelength λ c and electron effective mass as a function of the well thickness d 1 , valence band offset Λ , ratio R  =  d 1 / d 2 and temperature. We calculated the electronic transport parameters including transport scattering time, Fermi velocity and mean free path for the three investigated MQWs. The studied systems show a direct band gap, and the result of cutoff wavelength in the studied temperature range of 5 K to 300 K indicates that they are mid- and long-wave infrared detectors. We found that the band gap energy is highly dependent on d 1 . The results of density of states (DOS) and Fermi level energy ( E F ) show that the conductivity of the system varies from p -type to n -type following the increase in well thickness d 1 . Our theoretical findings are in good agreement with the available experimental measurements in previous studies, and they provide a route for future improvements in the engineering of infrared devices.