화학공학소재연구정보센터
Journal of Crystal Growth, Vol.458, 53-59, 2017
An investigation of near-infrared photoluminescence from AP-MOVPE grown InSb/GaSb quantum dot structures
In this work, the near-infrared photoluminescence (PL) of InSb/GaSb QD structures grown on GaSb substrate (2 degrees off (100)) using atmospheric pressure Metalorganic Vapor Phase Epitaxy is investigated. The structures are analyzed before capping and after capping using scanning probe microscopy and high resolution transmission electron microscopy (HRTEM), respectively. At 10 K, with an excitation power of 2 mW, a PL peak at similar to 732 meV is observed. Upon an increase in laser power to 120 mW, a blue shift of similar to 8 meV is noticed. This emission typically persists up to 60-70 K, after which it becomes weak. An SPM analysis of the size distribution of uncapped dots reveals a mono-modal distribution with an average density of similar to 5x10(10) cm(-2). However, a HRTEM investigation of the capped dots reveals the formation of an InGaSb quantum well-like structure, similar to 10 nm thick, which gives rise to the PL signal mentioned above.