GaSb/GaAs quantum dots with type-II band alignments prepared by molecular beam epitaxy for device applications

The growth procedures and device applications of GaSb/GaAs quantum dots (QDs) are investigated in this report. The influence of As flux on the GaSb QD morphologies and optical characteristics has revealed the importance of precise Sb/As flux control during Sb post-soaking procedures after GaSb deposition. With optimized GaSb QD growth conditions and long-term Sb post soaking procedure, room-temperature operation light-emitting diodes (LEDs) and high-temperature operation quantum-dot infrared photodetectors (QDIPs) are demonstrated. The results have revealed the possibilities of type-II GaSb QDs in the applications of optical devices.