High temperature grown transition metal oxide thin films: tuning physical properties by MeV N+-ion bombardment

Department of Physics, Anna University, 600 025, Chennai, India
Journal of Physics D Applied Physics (Impact Factor: 2.52). 06/2008; 41(12). DOI: 10.1088/0022-3727/41/12/125304

ABSTRACT In this paper, we present a systematic study on tuning the physical properties of high temperature (373 K) grown transition metal oxide thin films by the effect of 2 MeV nitrogen ion irradiation. Although we observe irradiation induced growth in crystallite sizes for both WO 3 and MoO 3 films, no structural phase change takes place in the films due to N + -ion beam irradiation even up to the fluence of 1 × 10 15 N + cm −2 . On the other hand, irradiation leads to a significant increase in the optical absorption and the surface roughness of the films. These observations are corroborated by micro-Raman analysis. The results are attributed to the MeV ion–matter interaction.

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