Self-Powered UV-Near Infrared Photodetector Based on Reduced Graphene Oxide/n-Si Vertical Heterojunction

G. Li, L. Liu, G. Wu, Wei Chen, S. Qin, Y. Wang, T. Zhang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

53 Citations (Scopus)

Abstract

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimA novel self-powered photodetector based on reduced graphene oxide (rGO)/n-Si p-n vertical heterojunction with high sensitivity and fast response time is presented. The photodetector contains a p-n vertical heterojunction between a drop-casted rGO thin film and n-Si. Contacts between the semiconductor layer (rGO, n-Si) and source-drain Ti/Au electrodes allow efficient transfer of photogenerated charge carriers. The self-powered UV-near infrared photodetector shows high sensitivity toward a spectrum of light from 365 to 1200 nm. Under the 600 nm illumination (0.81 mW cm?2), the device has a photoresponsivity of 1.52 A W?1, with fast response and recover time (2 ms and 3.7 ms), and the ON/OFF ratios exceed 104 when the power density reaches ?2.5 mW cm?2. The high photoresponse primarily arises from the built-in electric field formed at the interface of n-Si and rGO film. The effect of rGO thickness, rGO reduction level, and layout of rGO/n-Si effective contact area on device performance are also systematically investigated.
Original languageEnglish
Pages (from-to)5019-5026
Number of pages8
JournalSmall
Volume12
Issue number36
DOIs
Publication statusPublished - 28 Sep 2016
Externally publishedYes

Keywords

  • graphene
  • p-n vertical heterojunction
  • photodetectors
  • self-powered

ASJC Scopus subject areas

  • Biotechnology
  • Biomaterials
  • Chemistry(all)
  • Materials Science(all)

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