Impact of impurity-based phonon resonant scattering on thermal conductivity of single crystalline GaN
Abstract
The impact of impurities on the thermal conductivity of halide vapor phase epitaxy gallium nitride (GaN) was studied. Phonon resonances with impurities, modeled as Lorentz oscillators, were used to explain the much lower thermal conductivity than predicted by the Debye–Callaway model. The resonance energies for the oscillators were determined by Raman spectroscopy for Mn and by mass difference approximation for C and Fe. Employing the obtained resonance energies and proportionality factors extracted as fitting parameters, the modified model showed a good agreement with the experimental data. While the doping decreased thermal conductivity for all temperatures, the room temperature values started decreasing significantly once the doping levels approached ∼1019 cm−3. Consequently, required doping levels to achieve certain GaN-based devices may reduce the thermal conductivity of GaN by as much as 1/3.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 24, 2020
- Source ID
- 10.1063/5.0018824
Entities
People
- Ji Hyun Kim
- Michal Boćkowski
- Pegah Bagheri
- Pramod Reddy
- Ramón Collazo
- Robert Rounds
- Ronny Kirste
- Tomasz Sochacki
- Zlatko Sitar
Organizations
- Air Force Office of Scientific Research
- Army Research Office
- National Science Foundation
- North Carolina State University
- Office of Naval Research Global
- Polish Academy of Sciences
- United States Department of Energy