Photoelectron Spectroscopic Imaging and Device Applications of Large-Area Patternable Single-Layer MoS2 Synthesized by Chemical Vapor Deposition

본 논문은 이황화몰리브덴(MoS2)을 기상화학증착법(chemical vapor deposition; CVD)을 이용하여 대면적이며 균일한 단원자층 박막으로 성장하고, 성장과 동시에 소자 패터닝을 하여 전계효과 트랜지스터(field effect transistor)를 제작함에 있어서 에칭에 필요한 후처리 공정을 생략하면서 한번에 많은 소자를 손쉽게 만들 수 있는 기술 개발에 관한 연구결과이다. CVD 기법으로 성장한 MoS2 박막을 포항가속기연구소의 광전자분광(scanning photoelectron spectroscopic imaging: SPEM)을 통해 화학적 조성에 대해 직접적인 관찰을 하였고, 이를 통해 순도가 높은 양질의 MoS2원자층 박막임을 확인하였다. 이러한 연구는 나노미터 이하의 두께를 갖는 매우 얇은 반도체 소재의 산업적인 활용에 대한 가능성을 보인 연구결과이다.

Abstract: Molybdenum disulfide (MoS2) films, which are only a single atomic layer thick, have been synthesized by chemical vapor deposition (CVD) and have gained significant attention due to their bandgap semiconducting properties. However, in order for them to be useful for the fabrication of practical devices, patterning processes that can be used to form specific MoS2 structures must be integrated with the existing synthetic approaches. Here, we report a method for the synthesis of centimeter-scale, high-quality single-layer MoS2 that can be directly patterned during CVD, so that post-patterning processes can be avoided and device fabrication can be streamlined. Utilizing x-ray photoelectron spectroscopic imaging, we characterize the chemical states of these CVD-synthesized single-layer MoS2 films and demonstrate that the triangular-shaped MoS2 are single-crystalline single-domain monolayers. We also demonstrate the use of these high-quality and directly-patterned MoS2 films in electronic device applications by fabricating and characterizing field effect transistors.

Authors: Woanseo Park(서울대), Jaeyoon Baik(포항가속기연구소), Tae-Young Kim(서울대), Kyungjune Cho(서울대), Woong-Ki Hong(KBSI), Hyun-Joon Shin(포항공대), Takhee Lee(서울대)*

ACS Nano, Article ASAP
DOI: 10.1021/nn501019g
Publication Date (Web): April 14, 2014
Copyright © 2014 American Chemical Society
http://pubs.acs.org/doi/abs/10.1021/nn501019g