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

In this paper, an Al_yGa_1-yN/Al_xGa_1-xN/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 Schrödinger-Poisson equation and solving the carriers´ continuity equation. The calculation results show that the Al_yGa_1-yN/Al_xGa_1-xN/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_yGa_1-yN and AAl_xGa_1-xN/GaN layers. The calculation results are verified by the Korona´s experimental testing results at the end of this paper.