$\hbox{Al}_{y}\hbox{Ga}_{1-y}\hbox{N/Al}_{x} \hbox{Ga}_{1-x}\hbox{N/GaN}$ Double-Heterostructure Detector With Three Ultraviolet Spectral Band Responses

In this paper, an Al y Ga 1-y N/Al x Ga 1-x N/GaN (y >; x) double-heterostructure (DH) p-p-i-n ultraviolet (UV) detector is designed based on the influence of the polarization effect on the AlGaN/GaN heterostructure. The influences of doping concentration and Al composition in AlGaN on the photoelectric response of the UV detector are calculated and discussed by selfconsistent solving of the Schrodinger-Poisson equation and solving the carriers' continuity equation. The calculation results show that the Al y Ga 1-y N/Al x Ga 1-x N/GaN DH p-p-i-n UV detector presents a three-UV-response wavelength region with increasing bias voltage, and the three-UV-response wavelength region can be abnormally adjusted from 200 to 365 nm by changing the Al composition in the Al y Ga 1-y N and AAl x Ga 1-x N/GaN layers. The calculation results are verified by the Korona's experimental testing results at the end of this paper.