The Study of Interface Dynamics and Surface Termination Effect Realizing Large-Scale Epitaxial Growth of 2D MoS2

Abstract

Two-dimensional (2D) molybdenum disulfide (MoS2) shows a wide range of application possibilities due to the unique properties exhibited at the monolayer thickness. Therefore, many efforts have been performed to grow 2D MoS2. However, different growth results attributed to the various parameters still remain a challenge for its applications. In this dissertation, I focused on interfacial correlations to analyze the variations of growth and characteristics of MoS2. Especially, I observed the different growth behaviors exhibited by controlling the interfaces in chemical vapor deposition method. Chapter 1 introduces the overall characteristics exhibited at the 2D MoS2 including crystal structure and various properties. Furthermore, the various synthesis methods that have been applied to obtain 2D MoS2 is introduced. Chapter 2 investigates the influence of interaction between interface and precursors by utilizing the inorganic molecular precursor, MoOCl4 and H2S. Chapter 3 explores the effect of interfacial water existed on the surface, where it affects the optical properties of 2D MoS2. Chapter 4 investigates the effects of surface termination of sapphire depending on the temperature and growth environment, where MoS2 shows different crystallinity and grain size. These findings offer deeper insight into the interfacial dynamics between MoS2 and various interface structures, highlighting promising directions for optimizing interfacial structures. Deliberated investigation the growth behavior and properties of MoS2 relative to interfacial states will likely contribute significantly to advancing applications across a range of 2D materials beyond 2D MoS2.