The Effect of Plasma and Humidity on Characteristics of Monolayer MoS2
- 주제(키워드) MoS2 , Oxygen plasma , humidity , doping-effect
- 주제(DDC) 621.042
- 발행기관 아주대학교
- 지도교수 Ji-Yong Park
- 발행년도 2022
- 학위수여년월 2022. 8
- 학위명 석사
- 학과 및 전공 일반대학원 에너지시스템학과
- 실제URI http://www.dcollection.net/handler/ajou/000000032289
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
As a potential semiconductor material for various applications, the quality of Molybdenum disulfide (MoS2) and its control are the subject of substantial interest. Intrinsic defects are common phenomena in monolayer MoS2 which significantly impacts its properties. Among these, the most notable are sulfur vacancies. Understanding the stability and functionality of MoS2 is critical due to its susceptibility to oxidative environments and treatments. In this thesis, we analyzed humidity effects on electrical properties of monolayer MoS2 fieldeffect transistors to understand the water molecule absorption mechanism on monolayer MoS2 devices. The predominant effect of humidity is the modulation of the Schottky barriers at the MoS2 metal electrode contact, according to our findings. We also investigated the oxygen plasma impact on monolayer MoS2. We used Atomic Force Microscope (AFM) and Photoluminescence images to investigate the structural change. In addition, we also analyzed their influence on electrical characteristics of the monolayer MoS2 based fieldeffect transistors. We found the way to control the doping effect on monolayer MoS2 by modifying the plasma condition. The 𝑛/𝑝 doping induce in monolayer MoS2 due to the generation of Sulfur vacancies (𝑛 doping) and passivation of Sulfur vacancies (𝑝 doping).
more목차
1 Introduction 1
1.1 Motivation 6
1.2 Problem Statement 7
1.3 Thesis Contribution 7
1.4 Thesis Organization 7
2 Literature Review 8
3 Methodology 9
3.1 Experimental Setup 9
3.2 Growth of monolayer MoS2 using Atmospheric Pressure Chemical Vapor Deposition 11
3.3 MoS2 FET Device Fabrication 13
3.4 Plasma setup 14
3.5 Humid Environmental Control 16
3.6 Material and electrical characterization 17
4 Results and Discussion 18
4.1 Chemical Vapor Deposition grown monolayer MoS2 18
4.2 Electrical characterization of MoS2 FET in different humidities 21
4.3 Oxygen plasma effect on properties of monolayer MoS2 23
4.3.1 Oxygen Plasma induced n-doping 24
4.3.2 Oxygen Plasma induced p-doping 29
5 Conclusion 33
Appendix A List of Publications 34
Bibliography 35
