Main > Photonics Research >  Volume 7 >  Issue 8 >  Page B48-B54 > Article
Photonics Research, Vol. 7, Issue 8, B48-B54 (2019)

Magnesium ion-implantation-based gallium nitride p-i-n photodiode for visible-blind ultraviolet detection

Weizong Xu1,2,†,*, Yating Shi1,†, Fangfang Ren1, Dong Zhou1, Linlin Su1, Qing Liu1, Liang Cheng1, Jiandong Ye1, Dunjun Chen1, Rong Zhang1, Youdou Zheng1, and Hai Lu1,3,*

Author Affiliations

  • 1School of Electronic Science and Engineering, Nanjing University, Nanjing 210023, China
  • 2e-mail: wz.xu@nju.edu.cn
  • 3e-mail: hailu@nju.edu.cn

Abstract

In this work, a GaN p-i-n diode based on Mg ion implantation for visible-blind UV detection is demonstrated. With an optimized implantation and annealing process, a p-GaN layer and corresponding GaN p-i-n photodiode are achieved via Mg implantation. As revealed in the UV detection characterizations, these diodes exhibit a sharp wavelength cutoff at 365 nm, high UV/visible rejection ratio of 1.2×104, and high photoresponsivity of 0.35 A/W, and are proved to be comparable with commercially available GaN p-n photodiodes. Additionally, a localized states-related gain mechanism is systematically investigated, and a relevant physics model of electric-field-assisted photocarrier hopping is proposed. The demonstrated Mg ion-implantation-based approach is believed to be an applicable and CMOS-process-compatible technology for GaN-based p-i-n photodiodes.