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A non-destructive method for determination of thermal conductivity of YSZ coatings deposited on Si substrates

Abstract:

Thermal diffusivity (α) of YSZ coatings was determined by the phase lag method of the photo-acoustic signal for rear and frontal illuminations using a two-beam photo-acoustic cell. XRD results show the presence of a tetragonal phase with (101) and (112) orientations, and FTIR spectra exhibit the 2 Eu and F 1u modes as two broad bands in the frequency at 453 cm -1, 468 cm -1, corresponding to the tetragonal phase of ZrO 2. Thermal diffusivity was measured in the Si/YSZ system and also on the Si (100) substrate from which a simple two-layer system model. Via specific heat measurements at constant pressure (C p) using the (DSC) technique, and mass density (ρ) calculations using Archimedes and Aleksandrov's methods for both in-bulk and film YSZ samples, thermal conductivity (κ) was obtained. The results were: α = (0.0021 ± 0.0002) and (0.0023 ± 0.0002) cm 2 s -1, ρ = (4.7725 ± 0.005) × 10 3 and (5.883 ± 0.005) × 10 3 kg m -3, C p = (427 ± 14) J kg -1 K -1, and κ = (0.43 ± 0.06) and (0.57 ± 0.06) W m -1 K -1 for in-bulk and film YSZ samples, respectively. © 2012 Elsevier B.V. All rights reserved.