Low-temperature synthesis of transition metal dichalcogenides on flexible glass substrates via tellurium-assisted growth
Open Access
- Author:
- Simonson, Nicholas Andrew
- Area of Honors:
- Materials Science and Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Joshua Alexander Robinson, Thesis Supervisor
Joan Marie Redwing, Thesis Honors Advisor - Keywords:
- CVD
chemical vapor deposition
MOCVD
transition metal dichalcogenide
tungsten diselenide
molybdenum disulfide
MoS2
WSe2 - Abstract:
- Two-dimensional materials, particularly transition metal dichalcogenides such as molybdenum disulfide (MoS2) and tungsten diselenide (WSe2), are poised to be at the forefront of electronic and photonic materials due to their phenomenal physical, electronic, and optical properties. While materials such as graphene and hexagonal boron nitride serve as the conducting and insulating members of the 2D materials family, transition metal dichalcogenides fill the numerous gaps for semiconductors and optoelectronic materials. The growing flexible electronics industry is rapidly increasing demand for high-quality two-dimensional materials on flexible substrates, but these materials often require synthesis temperatures that are far too high for the substrates on which they are to be synthesized. In this work, we investigate adding tellurium to the reaction chamber in various chemical vapor deposition processes for transition metal dichalcogenides synthesis. This work demonstrates the growth of MoS2 via powder vaporization synthesis at 600°C, which was impossible without the addition of tellurium. The material grown via this method is thick and discontinuous, tending toward island growth instead of film deposition, but is crystalline. Also, tungsten diselenide is synthesized at 600°C, a significantly lower temperature than with conventional processes, via metalorganic chemical vapor deposition. Despite the prevalence of vertical growth via this method, there is evidence of film growth at this low temperature due to the presence of a metalorganic tellurium precursor, diethyl telluride.