Integrated GaN HEMT on Diamond: Heterointerface and Thermal Transport Fundamentals
Abstract
Innovative materials research is proposed for a GaN-diamond structure to greatly improve thermal management for energy and communications technologies. Diamond implementation is critical for mitigating self-heating effects that plague the efficiency of switches and power transistors. An innovative path is described through selective diamond growth in close proximity to the currentcarrying two-dimensional electron gas for efficient heat removal. Systematic studies will focus on diamond–on–GaN deposition and characterization, with particular attention on the interface materials and quality. Fabrication and testing of electrothermal test structures will be conducted. These will be used in combination with electrical and optical measurements to investigate the effects of deposition and heterointerface quality on fundamental properties, thermal conductivity and thermal boundary resistance (TBR). The impact of these material properties on transistor operational limits will be examined with the aid of simulations. The proposal describes transformative research of the material structure and the influence on key properties of the device structure. Four major objectives are: • Diamond on GaN and AlGaN, including AlOx and SiNx interfacial (and passivating) layers, to characterize materials, study materials integration issues, and optimize thermal characteristics. • Selective diamond deposition on GaN to investigate improvements in the polycrystalline diamond morphology, study effect of morphology on thermal conductivity of diamond and TBR. • Simulation-assisted design and fabrication of electrothermal test structures for measuring thermal conductivity and TBR; electrical and optical studies. • Simulations to generate predictive models of the material stack and electrothermal performance, including finite element simulations.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 12, 2016
- Source ID
- W911NF1510424
Entities
People
- Edwin Piner
Organizations
- Army Contracting Command
- Texas State University
- United States Department of Defense