• 文献标题:   Graphene GaN-Based Schottky Ultraviolet Detectors
  • 文献类型:   Article
  • 作  者:   XU K, XU C, XIE YY, DENG J, ZHU YX, GUO WL, XUN M, TEO KBK, CHEN HD, SUN J
  • 作者关键词:   gan, graphene, schottky ultraviolet uv detector
  • 出版物名称:   IEEE TRANSACTIONS ON ELECTRON DEVICES
  • ISSN:   0018-9383 EI 1557-9646
  • 通讯作者地址:   Beijing Univ Technol
  • 被引频次:   19
  • DOI:   10.1109/TED.2015.2453399
  • 出版年:   2015

▎ 摘  要

Graphene GaN-based Schottky ultraviolet detectors are fabricated. The monolayer graphene is grown by chemical vapor deposition. The graphene is much more transparent than metals, as confirmed by the fact that our devices retain their high responsivity up to 360-nm wavelength (corresponding to the band edge absorption of GaN). Importantly, by virtue of the tunable work function of graphene, the graphene GaN Schottky barrier height can be greatly enlarged. The built-in field is enhanced, and the detector performance is improved. The current ratio with and without luminescence is up to 1.6 x 10(4). The characteristic time constants of the devices are in the order of a few milliseconds. The device open-circuit voltage and short-circuit current are also increased. At last, special type Schottky devices consisting of GaN nanorods or surface-etched GaN are prepared for complementary study. It is found although the dry etching induced surface defects lead to an increase in the dark current, and these carrier traps also greatly contribute to the photoconductivity under luminescence, resulting in extraordinarily large responsivity (up to 360 A/W at -6 V).