Tuning the Metal–Insulator Transition Properties of VO2 Thin Films with the Synergetic Combination of Oxygen Vacancies, Strain Engineering, and Tungsten Doping

Nanomaterials

Mucahit Yilmaz¹  Shrouk E. Zaki²  Mohamed A. Basyooni²  Mohamed Shaban³  Mawaheb Al-Dossari⁴  Yasin Ramazan Eker⁵ 

[1] Department of Nanoscience and Nanoengineering, Institute of Science and Technology, University of Necmettin Erbakan, Konya 42060, Turkey;Department of Nanotechnology and Advanced Materials, Graduate School of Applied and Natural Science, Selçuk University, Konya 42030, Turkey;Department of Physics, Faculty of Science, Islamic University of Madinah, AlMadinah Almonawara 42351, Saudi Arabia;Research Center for Advanced Materials Science (RCAMS), King Khalid University, Abha 61413, Saudi Arabia;Science and Technology Research and Application Center (BITAM), University of Necmettin Erbakan, Konya 42060, Turkey;

关键词: thin films;    vanadium oxide;    thermochromic;    phase transition device;    metal–insulator transition;   

DOI  :  10.3390/nano12091470

来源: DOAJ

【 摘 要 】

Vanadium oxide (VO₂) is considered a Peierls–Mott insulator with a metal–insulator transition (MIT) at T_c = 68° C. The tuning of MIT parameters is a crucial point to use VO₂ within thermoelectric, electrochromic, or thermochromic applications. In this study, the effect of oxygen deficiencies, strain engineering, and metal tungsten doping are combined to tune the MIT with a low phase transition of 20 °C in the air without capsulation. Narrow hysteresis phase transition devices based on multilayer VO₂, WO₃, Mo_0.2W_0.8O_3, and/or MoO₃ oxide thin films deposited through a high vacuum sputtering are investigated. The deposited films are structurally, chemically, electrically, and optically characterized. Different conductivity behaviour was observed, with the highest value towards VO_1.75/WO_2.94 and the lowest VO_1.75 on FTO glass. VO_1.75/WO_2.94 showed a narrow hysteresis curve with a single-phase transition. Thanks to the role of oxygen vacancies, the MIT temperature decreased to 35 °C, while the lowest value (T_c = 20 °C) was reached with Mo_0.2W_0.8O₃/VO₂/MoO₃ structure. In this former sample, Mo_0.2W_0.8O₃ was used for the first time as an anti-reflective and anti-oxidative layer. The results showed that the MoO₃ bottom layer is more suitable than WO₃ to enhance the electrical properties of VO₂ thin films. This work is applied to fast phase transition devices.

【 授权许可】

Unknown