Elevated Transition Temperature of VO2 Thin Films via Cr Doping: A Combined Electrical Transport and Electronic Structure Study

• Published in: Journal of electronic materials 2023-06, Vol.52 (6), p.3818-3830
• Main Authors: Zzaman, M., Dawn, R., Franklin, J. B., Kumari, A., Ghosh, A., Sahoo, S. K., Verma, V. K., Shahid, R., Goutam, U. K., Kumar, K., Meena, R., Kandasami, A., Singh, V. R.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Doping; Electrical resistivity; Electromagnetism; Electronic structure; Electronics and Microelectronics; Electrons; Hall effect; Instrumentation; Lasers; Materials Science; Metal-insulator transition; Optical and Electronic Materials; Original Research Article; Oxidation; Photoelectric emission; Pulsed laser deposition; Pulsed lasers; Sapphire; Solid State Physics; Substrates; Temperature; Thin films; Transition temperature; Vanadium dioxide; Vanadium oxides; X ray photoelectron spectroscopy
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-023-10359-0

V 1− x Cr x O 2 (0 ≤  x  ≤ 0 . 3) (VCO) thin films were deposited onto r-sapphire substrates using a pulsed laser deposition method. The electronic structures of these compounds were investigated by x-ray photoemission spectroscopy (XPS), and the electrical transport measurements by four-probe electrical resistivity along with the Hall effect measurements. The XPS study shows that the valency of the Cr ions in the VCO films is 3 + and the V ions are in mixed states of 4 + and 5 + . From the resistivity-temperature measurements, the metal–insulator transition (MIT) temperature ( T C ) of Vanadium dioxide (VO 2 ) increases significantly upon Cr doping, while the hysteresis width and resistivity follow a gradual decrease. These findings will pave the way for the usage of VO 2 films in solar and electrical device applications where larger critical temperatures than pristine VO 2 are required. Graphic Abstract