Open AccessGraphene−silicon−graphene Schottky junction photodetector with field effect structure
Author(s) -
Fengsong Qian,
Jun Deng,
Xu Chen,
Yibo Dong,
Liangchen Hu,
Guosheng Fu,
Yiyang Xie,
Pengying Chang,
Jie Sun
Publication year - 2022
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.469963
Subject(s) - graphene , photodetector , materials science , schottky barrier , optoelectronics , silicon , heterojunction , doping , optics , nanotechnology , physics , diode
Graphene has unique advantages in ultrabroadband detection. However, nowadays graphene-based photodetectors cannot meet the requirements for practical applications due to their poor performance. Here, we report a graphene-silicon-graphene Schottky junction photodetector assisted by field effect. Two separate graphene sheets are located on both sides of the n-doped silicon to form two opposite lateral series heterojunctions with silicon, and a transparent top gate is designed to modulate the Schottky barrier. Low doping concentration of silicon and negative gate bias can significantly raise the barrier height. Under the combined action of these two measures, the barrier height increases from 0.39 eV to 0.77 eV. Accordingly, the performance of the photodetector has been greatly improved. The photoresponsivity of the optimized device is 2.6 A/W at 792 nm, 1.8 A/W at 1064 nm, and 0.42 A/W at 1550 nm, and the on/off photo-switching ratio reaches 10 4 . Our work provides a feasible solution for the development of graphene-based optoelectronic devices.