Study of fabrication and electronic characteristics of MoS2/graphene and MoSe2/graphene pn heterojunction diodes

• Main Authors: Wei-jhih Su, 蘇偉誌
• Other Authors: Kuei-yi Lee
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/68pwv2

碩士 === 國立臺灣科技大學 === 光電工程研究所 === 102 === The two-dimensional nano-material heterojunction combination has recently become an important trend in component development. In this project we combine (I) MoS2 and graphene and (II) MoSe2 and graphene (both two-dimensional materials) to produce a heterojunction and exhaustively study the interface property for heterojunction diode applications. Graphene is presently the thinnest two-dimensional material with good thermal conductivity and high carrier mobility. We used CH4 as the carbon source to grow high quality, large-area graphene onto a copper foil substrate. The graphene size was controlled using thermal chemical vapor deposition. The graphene Fermi level can be precisely controlled using the oxygen adsorption. Graphene can be tuned from zero-gap to p-type semiconductor material using the amount of adsorbed oxygen. MoS2 and MoSe2 films are currently the semiconductor materials with the most potential. Few-layer MoS2 (MoSe2) is an n-type semiconductor that has good mechanical strength, high carrier mobility, and has similar thickness as graphene. The MoS2 (MoSe2) band-gap increases with decreasing thickness when the chemical vapor transport method is used to grow bulk single-crystal MoS2 (MoSe2) with mechanical exfoliation to control the material thickness. Heterojunction diode components can be fabricated by combining the properties of MoS2 and graphene. The potential barrier can be controlled by. Combining the advantages of these two materials, we fabricated ultra-thin hetero pn junction and grouped the measured data into the database. Any in-depth study of two-dimensional material extended applications will contribute to the semiconductor industry.