Thermal conductivity of ultrathin nano-crystalline diamond films determined by Raman thermography assisted by silicon nanowires
Abstract
The thermal transport in polycrystalline diamond films near its nucleation region is still not well understood. Here, a steady-state technique to determine the thermal transport within the nano-crystalline diamond present at their nucleation site has been demonstrated. Taking advantage of silicon nanowires as surface temperature nano-sensors, and using Raman Thermography, the in-plane and cross-plane components of the thermal conductivity of ultra-thin diamond layers and their thermal barrier to the Si substrate were determined. Both components of the thermal conductivity of the nano-crystalline diamond were found to be well below the values of polycrystalline bulk diamond, with a cross-plane thermal conductivity larger than the in-plane thermal conductivity. Also a depth dependence of the lateral thermal conductivity through the diamond layer was determined. The results impact the design and integration of diamond for thermal management of AlGaN/GaN high power transistors and also show the usefulness of the nanowires as accurate nano-thermometers.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 01, 2015
- Source ID
- 10.1063/1.4922035
Entities
People
- Béla Pécz
- Erhard Kohn
- Julian Anaya
- Lajos Tóth
- Martin Kuball
- Mohammed Alomari
- Stefano Rossi
Organizations
- Hungarian Scientific Research Fund
- Institute for Technical Physics and Materials Science
- Office of Naval Research Global
- Ulm University
- University of Bristol