• 文献标题:   Improved performance of SiC radiation detectors due to optimized ohmic contact electrode by graphene insertion
  • 文献类型:   Article
  • 作  者:   JIA YP, SUN XJ, SHI ZM, JIANG K, WU T, LIANG HW, CUI XZ, LU W, LI DB
  • 作者关键词:   silicon carbide, radiation detector, graphene, energy resolution
  • 出版物名称:   DIAMOND RELATED MATERIALS
  • ISSN:   0925-9635 EI 1879-0062
  • 通讯作者地址:  
  • 被引频次:   3
  • DOI:   10.1016/j.diamond.2021.108355 EA MAR 2021
  • 出版年:   2021

▎ 摘  要

SiC as a typical wide bandgap semiconductor has exhibited potential application in alpha particle detectors. However, due to the comparatively high annealing temperature required for traditional fabrication technique of ohmic electrode, it is easy to excite impurities in the SiC epilayer, which act as scattering centers result in the declined device performance. In present work, a graphene layer is inserted between metal ohmic electrode and SiC. The graphene promotes the formation of carbon compounds and thus decreases ohmic contact resistance. Meanwhile, due to the Fermi level adjustable of graphene by external bias, the barrier of interface at graphene insert layer is enlarged at reverse bias. The built-in field accelerates the separation of photo-generated electronhole pairs. As a result, the graphene inserted device annealed at 400 degrees C achieved a 3.9%@-40 V energy resolution, and the device even without annealing achieved a 4.4%@-40 V energy resolution for Pu-239 alpha source, which are both better than that of traditional device without graphene layer annealed at 880 degrees C (6%@-40 V). The detailed mechanism has been discussed and suggested. Present work provides an effective strategy to improve device performance.