[OPTICAL REVIEW Vol. 16, No. 3 (2009) 371-374]
© 2009 The Optical Society of Japan

AlInGaN 310 nm Ultraviolet Metal–Insulator–Semiconductor Sensors with Photo-Chemical-Vapor-Deposition SiO2 Cap Layers

Chin-Hsiang CHEN*

Department of Electronic Engineering, Cheng Shiu University, Kaohsiung 830, Taiwan, R.O.C.

(Received July 13, 2008; Accepted January 26, 2009)

Al0.25In0.04Ga0.71N 310 nm near solar blind ultraviolet (UV) metal–insulator–semiconductor (MIS) sensors with different SiO2 cap layer thickness were successfully fabricated. With appropriate SiO2 layer thickness, the dark current of AlInGaN sensors was notably suppressed from 1.88× 10-6 to 1.91× 10-9 A, and the photo-generated carriers still could reach the electrodes by tunneling through the thin SiO2 layer under the illumination. It could be clearly seen that cut-off occurred at around 300/310 nm while the responses above the bandgap were flat.

Key words: AlGaN, MIS, sensor, ultraviolet

*E-mail address: chchen@csu.edu.tw