• 文献标题:   Silicon- and oxygen-codoped graphene from polycarbosilane and its application in graphene/n-type silicon photodetectors
  • 文献类型:   Article
  • 作  者:   GUO HA, JOU S, MAO TZ, HUANG BR, HUANG YT, YU HC, HSIEH YF, CHEN CC
  • 作者关键词:   graphene, silicon doping, oxygen doping, polycarbosilane, schottky diode, photodetector
  • 出版物名称:   APPLIED SURFACE SCIENCE
  • ISSN:   0169-4332 EI 1873-5584
  • 通讯作者地址:   Natl Taiwan Univ Sci Technol
  • 被引频次:   4
  • DOI:   10.1016/j.apsusc.2018.09.067
  • 出版年:   2019

▎ 摘  要

Properties of graphene can be modified by doping heteroatoms. Here we report the synthesis of a monolayer of silicon-and oxygen-codoped graphene (SiOG) using polycarbosilane as both the C and Si sources in a thermal chemical vapor deposition process and compare the SiOG with primitive graphene ( PG). Composition and structure of the PG and SiOG are analyzed by X-ray photoelectron spectroscopy and Raman spectroscopy. The SiOG produced from polycarbosilane has a ratio of [Si] to [Si]+[C] of 8.9%. Meanwhile, doping Si forms Si-C and C-Si-O bonds in graphene. Doping Si in graphene also introduces a defective structure in the graphene lattice. Graphene/Si Schottky diodes are prepared for performance comparison. Doping Si increases the barrier height of the graphene/Si Schottky diodes from 0.76 eV to 0.78 eV and changes the ideal factor from 3.8 to 2.8. The graphene/Si photodetectors are self-powered under UV irradiation. The ON/OFF ratios in 0.3 mW cm(-2) of 365 nm light at a zero bias voltage are respectively 3500 and 7600, and the rise times/fall times are respectively 11.6 ms/53.6 ms and 4.8 ms/14.3 ms for the PG/Si and SiOG/Si photodetectors. The relatively better performance of the SiOG/Si over PG/Si in UV sensing is possibly due to the lowering of the Fermi level of graphene by incorporation of Si and O.