Thermophysical Characterization of a CuO Thin Deposit

Abstract

CuO thin deposits on a tungsten carbide (consisting of 9% cobalt) substrate are obtained by physical vapor deposition (PVD) at ambient temperature. The longitudinal thermal conductivity as well as the thermal contact resistance at the deposit-substrate interface are investigated. A periodic photothermal experiment based on infrared radiometry is implemented. The amplitude between the periodic heat flux applied on the sample and the average temperature on the heated area are measured over a low frequency range. The method does not require the absolute measurement of these two quantities given that the thermal properties of the substrate are known. Scanning electron microscopy observations show strong anisotropy and columnar structure of the deposits. Moreover, the chemical composition of the films is obtained using the Auger technique. Cobalt diffuses from the substrate toward the deposit during the deposition process. It is demonstrated that the measured thermal conductivity of the CuO layer mainly rests on the microstructure of the layer instead of the roughness of the sample.

Optimization of Cuprous Oxides Thin Films to be used as Thermoelectric Touch Detectors

“…In that study, by tuning the oxygen flux and the holes concentration (up to 10 21 cm −3 ) CuO films have reached PF of 2.2 μW•m −1 •°C −2 . 17 Although being state of art, the PF values for these CO thin films are still very low and even with small thermal conductivities (as expected for these thin films 29,30 ) their figure of merit will be extremely low, in the order of 10 −5 , not allowing their usage as energy harvesters. What make them interesting is their high Seebeck values at room temperature.…”

Thermal characterization of the SiO2-Ge2Sb2Te5 interface from room temperature up to 400°C

“…The basic principle is to measure the phase lag and the amplitude of the periodic temperature response produced on the sample surface by a modulated laser beam. 19 A thermal diffusion model describing the heat transfer in the sample during the experiment enables the calculation of the theoretical phase lag and the amplitude as a function of frequency. The identification of the stack thermal resistance is performed by minimization of the gap between the theoretical and the experimental data.…”

“…19 The unknown thermal resistance R t = R i + R GST is identified using a minimization procedure based on the large-scale algorithm. This algorithm is a subspace trust region method and is based on the interior-reflective Newton method described in Ref.…”

Thermal conductivity of SiC after heavy ions irradiation

“…Since the temperature periodic variation at the heated area remains small (less than 10 K), it is assumed that the measured IR radiation is linearly proportional to this temperature. Heat transfer inside the sample is mathematically described from the heat diffusion equation and associated initial and boundary conditions [22]. According to the previous observations, the sample is thus viewed as a three layers material: the electronic interactions layer, the nuclear interactions layer and the un-irradiated SiC (Figs.…”