High-Temperature Coefficient of Resistance in Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> Thin Film

Despite the use of transition metal dichalcogenides being widespread in various applications, the knowledge and applications of Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> compounds are relatively limited. In this study, we deposited a MoW alloy on a Si substrate u...

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Bibliographic Details
Main Authors: Tsung-Shine Ko, En-Ting Lin, Xin-Wen Huang, Po-Tang Wu, Yi-Lin Yang
Format: Article
Language:English
Published: MDPI AG 2022-05-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/12/10/5110
Description
Summary:Despite the use of transition metal dichalcogenides being widespread in various applications, the knowledge and applications of Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> compounds are relatively limited. In this study, we deposited a MoW alloy on a Si substrate using a sputter system. Consequently, we successfully utilized a furnace to sulfurize the MoW alloy from 800 to 950 °C, which transferred the alloy into a Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> ternary compound. The Raman spectra of the Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> samples indicated an additional hybridized Raman peak at 375 cm<sup>−1</sup> not present in typical MoS<sub>2</sub> and WS<sub>2</sub>. With increasing sulfurization temperature, the scanning electron microscopy images revealed the surface morphology of the Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> gradually becoming a sheet-like structure. The X-ray diffraction results showed that the crystal structure of the Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> tended toward a preferable (002) crystal orientation. The I–V results showed that the resistance of Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> increased when the samples were sulfurized at a higher temperature due to the more porous structures generated within the thin film. Furthermore, a high-temperature coefficient of resistance for the Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> thin film sulfurized at 950 °C was about −1.633%/K<sup>−1</sup>. This coefficient of resistance in a Mo<sub>x</sub>W<sub>1−x</sub>S<sub>2</sub> thin film indicates its suitability for use in thermal sensors.
ISSN:2076-3417