Barrier-height and well-width dependence of photoluminescence from AlGaN-based quantum well structures for deep-UV emitters

We report barrier-height and well-width dependence of room-temperature photoluminescence from AlGaN-based quantum well structures for deep-UV light emitting device applications. A quantum well (QW) sample consisting of 1.5 nm-Al0.15Ga0.85N wells/7 nm-Al0.40Ga0.60N barriers showed the largest emission intensity in our samples. Quantum confined Stark effect on the emission energy and intensity in wide-well conditions, carrier penetration into the barrier regions in narrow well conditions and heterointerface defect formation were comprehensively considered in the discussion. If the heterointerface defect formation is ideally suppressed by optimal growth conditions, QW structures with narrow wells and high barriers will be a better design for highly efficient deep-UV light emitting devices.