Title of Paper:Simultaneous Measurement of Thermal Conductivity and Specific Heat in a Single TDTR Experiment

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Date of Publication:2018-01-01

Journal:INTERNATIONAL JOURNAL OF THERMOPHYSICS

Included Journals:SCIE、EI

Volume:39

Issue:1

ISSN No.:0195-928X

Key Words:Specific heat; Thermal conductivity; Thermal property; Time-domain thermoreflectance; Two-step fitting method

Abstract:Time-domain thermoreflectance (TDTR) technique is a powerful thermal property measurement method, especially for nano-structures and material interfaces. Thermal properties can be obtained by fitting TDTR experimental data with a proper thermal transport model. In a single TDTR experiment, thermal properties with different sensitivity trends can be extracted simultaneously. However, thermal conductivity and volumetric heat capacity usually have similar trends in sensitivity for most materials; it is difficult to measure them simultaneously. In this work, we present a two-step data fitting method to measure the thermal conductivity and volumetric heat capacity simultaneously from a set of TDTR experimental data at single modulation frequency. This method takes full advantage of the information carried by both amplitude and phase signals; it is a more convenient and effective solution compared with the frequency-domain thermoreflectance method. The relative error is lower than 5% for most cases. A silicon wafer sample was measured by TDTR method to verify the two-step fitting method.