Effects of well thickness and Si doping on the optical properties of GaN/AlGaN multiple quantum wells

Abstract
Effects of well thickness and Si doping on the optical properties of GaN/AlGaN (MQWs) have been investigated by picosecond time-resolved photoluminescence (PL) measurements. Our results have yielded that (i) the optical transitions in nominally undoped MQWs with narrow well thicknesses (Lw40 Å) at low temperatures, and (iii) Si doping improved significantly the crystalline quality of MQWs of large well thicknesses (Lw>40 Å). The implications of these results on the device applications based on III-nitride MQWs have been discussed.