title: Lithography-free plasma-induced patterned growth of MoS2 and its heterojunction with graphene.
abstract: Application-oriented patterned growth of transition metal dichalcogenides (TMDCs) and their heterojunctions is of critical importance for sophisticated, customized two-dimensional (2D) electronic and optoelectronic devices; however, it is still difficult to fabricate these patterns in a simple, clean, and high controllability manner without using optical lithography. Here, we report the direct synthesis of patterned MoS2 and graphene-MoS2 heterojunctions via selective plasma treatment of a SiO2/Si substrate and chemical vapor deposition of MoS2. This method has multiple merits, such as simple steps, a short operating time, easily isolated MoS2 layers with clean surfaces and controllable locations, shapes, sizes and thicknesses, which enable their integration into the device structure without using a photoresist. In addition, we demonstrate the direct growth of patterned graphene-MoS2 heterojunctions for the fabrication of transistor. This study reveals a novel method to fabricate and use patterned MoS2 and graphene-MoS2 heterojunctions, which could be generalized to the rational design of other 2D materials, heterojunctions and devices in the future.
authors.affiliation: Center for Strain Engineered Electronic Devices, School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. ahnj@yonsei.ac.kr.
authors.forename: Xiang
authors.initials: X
authors.lastname: Chen
authors.affiliation: Center for Strain Engineered Electronic Devices, School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. ahnj@yonsei.ac.kr.
authors.forename: Yong Ju
authors.initials: YJ
authors.lastname: Park
authors.affiliation: Center for Strain Engineered Electronic Devices, School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. ahnj@yonsei.ac.kr.
authors.forename: Tanmoy
authors.initials: T
authors.lastname: Das
authors.affiliation: Center for Strain Engineered Electronic Devices, School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. ahnj@yonsei.ac.kr.
authors.forename: Houk
authors.initials: H
authors.lastname: Jang
authors.affiliation: Center for Strain Engineered Electronic Devices, School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. ahnj@yonsei.ac.kr.
authors.forename: Jae-Bok
authors.initials: JB
authors.lastname: Lee
authors.affiliation: Center for Strain Engineered Electronic Devices, School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea. ahnj@yonsei.ac.kr.
authors.forename: Jong-Hyun
authors.initials: JH
authors.lastname: Ahn