Effect of Thickness of Single-Phase Antimony and Tellurium Thin Films on Their Thermal Conductivities

Abstract

We present the effects of film thickness and grain size on the out-of-plane thermal conductivities of single-phase Sb and Te thin films, which are of great interest for thermoelectric device applications. The thermal conductivities of the films were measured by the four-point-probe 3Ωo method, at room temperature. For this study, 50-, 100-, and 200-nm-thick Sb and Te thin films were prepared by electron-beam evaporation at room temperature. From the measured thermal conductivities, we evaluated that the average thermal conductivities of the Sb and Te thin films were 5.9-10.2 W/(m x K) and 0.8-1.2 W/(m x K), respectively, at room temperature. This result reveals that the thickness and grain size of each thin film strongly affect the modulation of its thermal conductivity at room temperature.

Anisotropic temperature-dependent thermal conductivity by an Al2O3 interlayer in Al2O3/ZnO superlattice films

“…Figures 1(c) and (d) show schematic of the experimental setup for the four-point-probe 3-ω measurement for measuring both the cross-plane (figure 1(c)) and in-plane (figure 1(d)) thermal conductivity. The evaluation of the thermal conductivity using 3-ω measurements has been extensively studied, including in our previous works [23,[29][30][31][32][33]. In short, the 3-ω method is normally an alternating current technique in which a thin film (Ti/Au=10/300 nm) is patterned on a SiO 2 /Si substrate (figures 1(c) and (d)) for measuring the cross-plane and in-plane thermal conductivity.…”

“…The electrodes can be used as a heater and a thermometer, as shown in figures 1(c) and (d). Detailed information on the fabrication of the electrodes on the samples can be found elsewhere [30]. In the crossplane thermal conductivity measurement, a wide heater (electrode with a width of ∼20 μm) was used to measure the temperature response in the cross-plane direction, whereas one with smaller width (<400 nm) was used for the in-plane thermal conductivity measurements, as in previous works [22,23,34].…”

One-Pot Hydrothermal Synthesis of Thin Tellurene Nanosheet and Its Formation Mechanism

“…The typical Te sample exhibits a relatively regular sheet shape with a uniform smooth surface, which shows the diameter of 4 μm, indicating that the synthesized Te nanosheets is relatively large. In order to further characterize the chemical composition, the energy dispersive X-ray spectrum (EDS) was used (see Figure 1 [20,25]. All corresponding peaks for the Te products are sharp and well defined indicating that a pure phase crystalline was formed.…”

Enhanced Cross-Plane Thermoelectric Figure of Merit Observed in an Al2O3/ZnO Superlattice Film by Hole Carrier Blocking and Phonon Scattering

“…A detailed sample preparation description, particularly for the AO/ZnO superlattice film, can be found in our previous works. , Surface morphologies, crystal structure, and cross-sectional interface information with composition profile were studied using high resolution transmission electron microscopy (HR-TEM) and energy dispersive X-ray spectrometry (EDX). Figure a,b shows four point probe 3-ω measurement outcomes for cross-plane thermal conductivity. − Detailed information with regard to heater and electrode fabrication on the samples can be found elsewhere . This technique is one of the best techniques to evaluate temperature-dependent thermal conductivity for thin and thick films with uncertainty ≤4%.…”

“…23−28 Detailed information with regard to heater and electrode fabrication on the samples can be found elsewhere. 25 This technique is one of the best techniques to evaluate temperature-dependent thermal conductivity for thin and thick films with uncertainty ≤4%. Superlattice film thermal conductivity is generally determined from the 3-ω measurement as…”