• 文献标题:   High-responsivity photodetectors made of graphene nanowalls grown on Si
  • 文献类型:   Article
  • 作  者:   LI LF, DONG YB, GUO WL, QIAN FS, XIONG FZ, FU YF, DU ZF, XU C, SUN J
  • 作者关键词:  
  • 出版物名称:   APPLIED PHYSICS LETTERS
  • ISSN:   0003-6951 EI 1077-3118
  • 通讯作者地址:   Beijing Univ Technol
  • 被引频次:   4
  • DOI:   10.1063/1.5097313
  • 出版年:   2019

▎ 摘  要

Graphene nanowalls (GNWs) are wall-like graphene nanosheets that are oriented vertically on a substrate. GNWs have a unique structure and special optoelectronic properties, which enables their use in photodetectors. In this paper, we use plasma-enhanced chemical vapor deposition to directly grow GNWs onto the surface of an n-type lightly doped Si substrate and to optimize the quality of the GNWs by adjusting the growth time and temperature. Furthermore, after the GNWs are lithographically patterned, we use a GNW-Si Schottky structure to develop photodetector arrays which are capable of detecting light from the visible to infrared light spectral range. Throughout the process, GNWs are directly synthesized on a Si substrate without using a catalyst or a transfer step. The process is simple and efficient. Under laser illumination at a wavelength of 792nm, the highest on/off ratio at zero bias is approximately 10(5), and the specific detectivity is 7.85x10(6) cm Hz(1/2)/W. Under a reverse bias of 4V, the measured responsivity of the detector reaches 1A/W at room temperature. The device can also produce a light response in the near-infrared band. Upon laser illumination at a wavelength of 1550nm, the detector shows a responsivity of 12mA/W at room temperature.