Improve the electrical and optical performance of deep ultraviolet light-emitting diodes with a w-shaped p-AlGaN layer
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We theoretically investigate the effects of three independent p-type contact layers on the photoelectric properties of deep ultraviolet light-emitting diodes (DUV-LEDs). From the simulation results, the DUV-LED using a w-shaped p-AlGaN layer has a better photoelectric performance. The internal quantum efficiency and output power in the new structure are significantly increased compared to the two other structures. Besides, the novel structure reveals lower contact resistance and higher electroluminescence intensity, and the efficiency droop is very small at 200 mA injection current. These improvements are attributed to not only decreased electron leakage but also increased hole injection efficiency, thereby enhancing radiative recombination rates. The specially designed p-type layer provides an attractive solution for improving the photoelectric performance of DUV-LEDs with the Al-rich p-AlGaN contact layers.
Project supported by Foreign Special Fund for Science and Technology Innovation and Development of Guangzhou, Guangdong Province, China (Grant No. 201807010083).
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