N-polar III-nitride quantum well light-emitting diodes with polarization-induced doping

作者：Verma Jai^*; Simon John; Protasenko Vladimir; Kosel Thomas; Xing Huili Grace; Jena Debdeep

来源：Applied Physics Letters, 2011, 99(17): 171104.

DOI：10.1063/1.3656707

Nitrogen-polar III-nitride heterostructures present unexplored advantages over Ga(metal)-polar crystals for optoelectronic devices. This work reports N-polar III-nitride quantum-well ultraviolet light-emitting diodes grown by plasma-assisted molecular beam epitaxy that integrate polarization-induced p-type doping by compositional grading from GaN to AlGaN along N-face. The graded AlGaN layer simultaneously acts as an electron blocking layer while facilitating smooth injection of holes into the active region, while the built-in electric field in the barriers improves carrier injection into quantum wells. The enhanced doping, carrier injection, and light extraction indicate that N-polar structures have the potential to exceed the performance of metal-polar ultraviolet light-emitting diodes.

• 出版日期2011-10-24