Influence of proton irradiation on phase variation and optical properties of VO₂(B) thin film

ABSTRACT

The present work is focused on the fabrication of VO₂(B) thin films by magnetron sputtering followed by proton irradiation using 5 MeV tandem accelerator. For the study of phase transitions, the proton ion beam applied was to the VO₂(B) thin films at the rate of 1 × 10¹⁵ ions/cm², 2 × 10¹⁵ ions/cm², 7.5 × 10¹⁵ ions/cm², 5 × 10¹⁶ ions/cm² respectively. The VO₂(B) thin-film shows prominent phase variation from VO₂(B) to VO₂(A) along with the amorphization phenomenon with the increasing doses of proton ions. The diffused reflectance spectroscopy shows increasing trends in reflectance from 20 to 39%. Energy bandgap was determined using a Tauc plot showing efficient decreasing trends w.r.t ion beam doses. Raman spectroscopy shows vibrations in the range from 144 to 883 cm⁻¹ with different bands, confirming the phase transition towards VO₂(A) by proton ion beam irradiation. The results are useful and promising for the smart use of various phases of VO₂(B) thin film.

KEYWORDS:

• VO₂(B) thin films
• VO₂(A)
• proton ion beam
• phase variation
• smart material
• reflectance degradation

Acknowledgement

The authors would like to thank all the staff members of the Accelerator Laboratory of Experimental Physics Laboratory at the National Center for Physics, Islamabad for their valued support. The authors are thankful to Dr. Syed Salman Hussain, Umair Ibrahim, Muhammad Afan of the Department of Physics, IIUI.

Disclosure statement

No potential conflict of interest was reported by the author(s).