Limits to Fourier theory in high thermal conductivity single crystals

Abstract

We report the results of time-domain thermoreflectance (TDTR) experiments that examine the ability of Fourier theory to predict the thermal response in single crystals when heater dimensions are small. We performed TDTR measurements on Al-coated diamond, 6H-SiC, GaP, Ge, MgO, GaAs, and GaSb single crystals with a wide range of laser spot size radii, 0.7 μm < w0 < 12 μm. When the laser spot-size is large, w0 ≈ 12 μm, TDTR data for all crystals are in agreement with predictions of Fourier theory with bulk thermal conductivity values. When the laser spot-size is small, w0 < 2 μm, there are significant differences between the predictions of Fourier theory and TDTR data for all crystals except MgO.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 16, 2015
Source ID
10.1063/1.4935987

Entities

People

  • David G. Cahill
  • R. B. Wilson

Organizations

  • Air Force Office of Scientific Research
  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Materials science

Readers

  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.
  • Semiconductor Device Technology
  • Thermal Physics or Thermal Science.

Technology Areas

  • Directed Energy