Graphene, MoS₂ And Graphene/MoS₂ Heterojunction:Preparation And Characterization

Two-dimensional layer semiconductor materials have broad applications in light detectors, photovoltaic devices, and laser optoelectronics due to their excellent physical, chemical and mechanical properties. High-performance optoelectronic devices need large area, high quality and low defects nanomaterial. However realizing the growth of large and high quality layered materials still faces great challenges. In order to break the bottlenecks, this paper mainly studied the controllable preparation of graphene, molybdenum disulfide(MoS2) and graphene/MoS2 heterojunction. The main research contents include:1. Successfully synthesis large area, high quality graphene film on copper substrate. And realize the directional transfer of large-area graphene films with the improved transferring method. The work also reveals the growth mechanism of graphene on copper substrate. At the same time the growth substrate, hydrogen(H2), methane(CH4) and temperature effects on graphene properties have been systematically studied. The graphene has been used to build the solar cell.2. High quality and large area MoS2 thin film can be directly grown on SiO2/Si substrate via atmospheric pressure. Chemical vapor deposition method(chemical vapor deposition, CVD) can be adopted to systematically study the growth factors such as temperature, time, flow rate and other factors on the effect of MoS2 thin film. The field effect transistor can be directly fabricated on MoS2 thin film without transferring.3. The in-situ growth of large area MoS2 films on graphene has been achieved. The work also studies the preparation of graphene/MoS2 heterojunction via physical vapor deposition method(physical vapor deposition, PVD) method. And then research the effects of process parameters on the material growth.