Structural and electrochemical properties of vanadium oxide thin films grown by d.c. and r.f. reactive sputtering at room temperature

• Published in: Thin solid films Vol. 460; no. 1; pp. 41 - 47
• Main Authors: Yoon, Y.S., Kim, J.S., Choi, S.H.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 22.07.2004; Elsevier Science
• Subjects: Amorphous; Cross-disciplinary physics: materials science; rheology; Crystalline; Deposition by sputtering; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Sputtering; V 2O 5 thin film; Amorphous; V 2O 5 thin film; Crystalline; Sputtering; Grain size; Amorphous material; Scanning electron microscopy; RBS; Vanadium oxides; Transition element compounds; Binary compounds; V2O5 thin film; XRD; Infrared spectra; Experimental study; Thin films; Growth from vapor; Cathode sputtering; Preparation; Fourier transform spectra; Chemical composition; Reactive sputtering; Radiofrequency sputtering
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2004.01.075

Vanadium oxide thin films were grown at room temperature by direct current and radio-frequency reactive sputtering systems to compare the structural and electrochemical properties. Rutherford backscattering spectrometry and Fourier transform infrared measurements reveal that the composition of the as-deposited films consists of the V 2O 5 phase regardless of the deposition methods. Wide-angle X-ray diffraction measurements show that the crystallinity of the as-deposited V 2O 5 films is different depending on the deposition method. Films deposited by direct current reactive sputtering were amorphous, whereas films deposited by radio-frequency reactive sputtering were crystalline. Scanning electron microscopy measurements show that the V 2O 5 films grown by radio-frequency reactive sputtering had a large grain size but the films grown by direct current reactive sputtering were amorphous. Charge–discharge measurements taken at room temperature with a constant current clearly indicate that the films grown by direct current sputtering demonstrated typical amorphous behavior, whereas the V 2O 5 films grown by radio-frequency sputtering demonstrated the discharge behavior of crystalline V 2O 5. The origin of the structural and electrochemical properties of film grown by radio-frequency reactive sputtering is a self-bias effect. The self-bias effect induces ion bombardment during the growth of vanadium oxide thin film. These results suggest that direct current reactive sputtering is more desirable for growing amorphous V 2O 5 thin film than radio-frequency reactive sputtering.