Tailoring of Opto-Electronic Properties of 2D Semiconductors via Defect Engineering
Abstract
A promising class of 2D materials is transition metal dichalcogenides (TMDs, chalcogenide = S, Se, or Te). TMDs form, like graphene, a layered structure in 3D, and single layers can be grown or isolated. Several TMDs such as MoS2 and MoSe2 are semiconductors, just like silicon, the foundation of modern electronics and solar cells. Unlike silicon, TMDs are flexible and resistant to shock, thus have immense promise for applications in wearable electronics, flexible displays, and miniature/low power devices.The goal of this project is to understand the effect of defects on the electrical transport andoptical properties of TMDs. The promising applications of these semiconducting structures arenot yet realized because of the difficulties related to scaling up their production whilemaintaining a high quality. Defects are, in fact, unavoidable during growth, and significantadvances could be made if we learned to work with imperfect materials.Here, the interactions of TMDs with light at the micrometer scale and with electrons at theatomic scale are used to measure the local optical properties (such as bandgap—a semiconductorproperty), the defect density, and the defect distribution. These results are then directly coupledwith the electron mobility measured from the performance of a TMD-based transistor, and withthe observation of defect motion during electronic device operation. Together, these results willgenerate a complete framework of understanding of the effect of defects on the optical andelectronic properties of TMDs—thereby establishing how much and what kinds of defects aretolerable for 2D semiconductor-based devices.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 02, 2017
- Source ID
- FA95501710202
Entities
People
- Emilie Ringe
Organizations
- Air Force Office of Scientific Research
- Rice University
- United States Air Force