• 文献标题:   Hybrid GaAsSb/GaAs Heterostructure Core-Shell Nanowire/Graphene and Photodetector Applications
  • 文献类型:   Article
  • 作  者:   NALAMATI S, DEVKOTA S, LI J, LAVELLE R, HUET B, SNYDER D, PENN A, GARCIA R, REYNOLDS L, IYER S
  • 作者关键词:   nanowire, graphene, oxygen plasma, gaassb, molecular beam epitaxy, photodetector
  • 出版物名称:   ACS APPLIED ELECTRONIC MATERIALS
  • ISSN:   2637-6113
  • 通讯作者地址:   North Carolina A T State Univ
  • 被引频次:   0
  • DOI:   10.1021/acsaelm.0c00433
  • 出版年:   2020

▎ 摘  要

We report the growth of vertical, high-quality GaAs(0.9)Sb(0.1 )nanowires (NWs) with improved density on oxygen (O-2) plasma-treated monolayer graphene/SiO2/p-Si(111) by self-catalyzed molecular beam epitaxy. An O-2 plasma treatment of the graphene under mild conditions enabled modification of the surface functionalization and improved reactivity of the graphene surface to semiconductor adatoms. The rise in the disorder peak of the Raman mode, decreased surface conductivity, and creation of additional O-2 groups of plasma-treated graphene compared to that of pristine graphene confirmed functionalization of the graphene. To enhance the nucleation centers further for the vertical yield of NWs on the graphene surface, NWs were grown on a higher Sb composition GaAs(0.6)Sb(0.4 )stem for surface engineering the graphene surface via the surfactant effect of Sb and for better lattice matching. The NWs grown under optimal conditions exhibited a zinc blende crystal structure with no discernible structural defects. The NWs with a GaAs-passivated shell exhibited photoluminescence emission at 1.35 eV at 4 K and 1.28 eV at room temperature. The ensemble device fabricated with a top segment of GaAsSb NW-doped n-type using a GaTe captive source exhibited an optical responsivity of 110 A/W with a detectivity of 1.1 x 10(14) Jones. These results of hybrid GaAsSb NW heterostructure/graphene devices show significant potential toward the fabrication of flexible near-infrared photodetector device applications. Further, the simple and efficient O-2 plasma treatment approach for surface engineering of graphene in conjunction with a high Sb compositional stem has shown to be a promising route that can be broadly applicable for the growth of other III-V ternary material systems for improving the vertical yield of NWs.