알칼리 금속 조촉매를 활용한 이황화몰리브덴 (MoS2) 단일층 박막 성장에서 성장 메커니즘에 관한 연구 = Study on growth mechanism of monolayer MoS2 synthesized with alkali metal promoter

다국어 초록 (Multilingual Abstract)

In recently years, two-dimensional semiconducting transition metal dichalcogenides have attracted much attention because of its unique structure as well as chemical and physical properties. Particularly, single-layer molybdenum disulfide (MoS2) exhibits outstanding optical properties. Many researchers utilize various seeding promoters to achieve the MoS2 thin layer. Composite organic compounds has low thermal stability. Here, we report MoS2 monolayer growth using inorganic seeding promoter containing alkali metal ions and the role of inorganic seeding promoter enhancing the nucleation of molybdenum disulfide by chemical vapor deposition. In this growth process, molybdenum oxide as precursor react with seeding promoter including alkali metal on the substrate, this reaction produces alkali metal molybdate, and then formed compounds play the nucleation sites in MoS2 growth. The presence of them increase partial pressure of molybdenum on substrate and is sulfurized to MoS2. In the study, we investigated the role of alkali metal ion is confirmed. A variety of measurement techniques were characterized high crystalline quality, uniformity and layer numbers of the fabricated MoS2 thin layer. Consequently, we suggest the growth mechanism of MoS2 by using the alkali metal ions as inorganic seeding promoter and expect this method paves the new routes for the advanced fundamental study and development of practical device applications with monolayer MoS2

목차 (Table of Contents)

• 1장 서 론 1
• 1.1 이황화몰리브덴 2
• 1.2 화학 기상 증착법 2
• 1.3 MoS2 성장 연구 동향 5
• 1.4 연구 목표 6
• 2장 실험 장비 및 방법 7
• 2.1 화학 기상 증착 장비 7
• 2.2 조촉매 수용액 및 기판 준비 과정 9
• 2.2.1 조촉매 수용액 준비 및 기판 코팅 9
• 2.2.2 SiO2/Si 기판 세정 공정 9
• 2.3 이황화몰리브덴 성장 10
• 2.4 실험 장치 및 분석 방법 10
• 2.4.1 광학 현미경 10
• 2.4.2 원자 힘 현미경 11
• 2.4.3 주사전자현미경 12
• 2.4.4 투과전자현미경 12
• 2.4.5 라만 분광기 13
• 2.4.6 광 루미네선스 14
• 2.4.7 X선 광전자 분광법 15
• 3장 실험 결과 및 분석 16
• 3.1 PTAS를 활용한 이황화몰리브덴 성장 16
• 3.2 NaCl를 활용한 이황화몰리브덴 성장 21
• 3.3 Alkali hydroxide를 활용한 이황화몰리브덴 성장 30
• 3.4 Alkali metal 조촉매를 활용한 이황화몰리브덴 성장 메커니즘 모델 34
• 4장 요약 및 결론 41
• 5장 추후 연구 계획 43
• 참 고 문 헌 44
• 감사의 글 48