Growth and characterization of large area MoS2 thin film

• Main Author: Tham, Seng Yung
• Other Authors: Tay Beng Kang
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Microelectronics
• Online Access: http://hdl.handle.net/10356/60850
• Institution: Nanyang Technological University

Monolayer molybdenum disulfide (MoS2), a direct bandgap 2D crystal, has been receiving great attention due to their unique electrical properties and potential in optoelectronics. Many exciting devices can be fabricated if high quality and large scale synthesis of these layers are possible. Mechanical exfoliation is the most commonly used method to prepare MoS2 monolayers. However, the size of the layers produced is limited and it restricts its application in a commercially viable device. Many methods such as liquid exfoliation, physical vapour deposition and electrochemical synthesis have since been proposed to synthesize MoS2 monolayers. Recently, chemical vapour deposition methods have shown great promise in the synthesis of large and highly crystalline atomic MoS2 layers. In this project, MoS2 layers had been grown with the chemical vapour deposition (CVD) method of sulfurization of molybdenum trioxide (MoO3). The growth process was conducted with different temperature and time to investigate their effects on the growth process. The synthesized MoS2 layers had been characterized with optical microscope, Raman spectroscopy, photoluminescence (PL) spectroscopy and atomic force microscopy (AFM). The results have shown that MoS2 thin films had been successfully synthesized. The edge length of the films increased with the temperature applied while the relationship of the growth time to the growth of MoS2 is yet to be fully determined, this may need more work done in the future.