Proposal Number CTS-0553649 Principal Investigator Shi, Li Affiliation University of Texas at Austin Proposal Title Thermal Transport at Nanoscale Point and Line Constrictions and Interfaces
Thermal transport at nanometer scale point and line constrictions and interfaces is a fundamental problem that is important for a number of technologies, such as scanning probe microscopy, novel thermal interface materials, and nanostructural electronic and thermoelectric devices. As of today, few measurement results of thermal resistances at nanoscale constrictions and interfaces are available. Moreover, although there have been extensive theoretical studies of contact thermal resistance between two solids, most of the existing analytical models have been developed for macro to micro scale contacts. The research objective of this program is to measure and model thermal transport at nanoscale point and line constrictions and interfaces. Ultrahigh vacuum atomic force microscopy and nanofabricated structures will be employed to measure the thermal resistance of nanometer size point contacts, line interfaces, and Si constrictions. A molecular dynamics (MD) simulation method will be used to calculate the thermal resistance and temperature distribution at these nanoscale constrictions and interfaces. In addition to heat conduction, the calculation will investigate the influences of near- and far- field radiation transfer on the temperature distribution and thermal resistance. The results from the measurements and calculations will be correlated and used to verify and improve analytic models. Intellectual Merit. The proposed research will obtain measurement data of thermal resistance at nanoscale constrictions and interfaces. The results from the measurements and simulations will fill in a knowledge gap and provide timely support for thermal design and thermal management of electronic and thermoelectric devices as well as new scanning probe microscopy and data storage methods. Broader Impacts. The research will provide training opportunities for two graduate students and an undergraduate student participant in the NSF Research Experience for Undergraduates (REU) program. The research results will be used as case studies in two graduate courses and one new undergraduate technical elective course. The two investigators will give short lectures in the seminar series organized by local ASME student organization, and will actively participate in K-12 outreach activities sponsored by the university. The close collaboration with an industrial researcher will have mutual benefits for the education of the participating students and the transfer of knowledge gained from this study for industrial applications.
