Effect of partial pressure of oxygen, target current, and annealing on DC sputtered tungsten oxide (WO3) thin films for electrochromic applications

• Published in: Solid state ionics Vol. 399; p. 116275
• Main Authors: Kumar, K Naveen, Sattar, Sheik Abdul, Shaik, Habibuddin, G V, Ashok Reddy, Jafri, R. Imran, Dhananjaya, Merum, Pawar, Amruth S., Prakash, Nunna Guru, Premkumar, R., Ansar, Sabah, Chandrashekar, L.N., Aishwarya, P.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-10-2023
• Subjects: EC properties; Optical transmittance; pO2; Sputtering; Target current; Temperature; Optical transmittance; Temperature; pO2; Target current; Sputtering; EC properties
• ISSN: 0167-2738; 1872-7689
• DOI: 10.1016/j.ssi.2023.116275

Tungsten oxide (WO3) thin films were prepared on Corning (CG) and Fluorine doped tin oxide (FTO) glass substrates at partial pressure of oxygen (pO2) 4 × 10−2 Pa and 8 × 10−2 Pa using DC magnetron sputtering (DCMs). In this work, we have varied the deposition parameters like pO2, target currents, and temperature. At pO2 4 × 10−2 Pa and 8 × 10−2 Pa samples were deposited at target currents of 50 mA and 100 mA, the maintained growth conditions are RT (substrate temperature 28 °C), Pre annealed (substrate temperature 400 °C), and Post annealed (annealing temperature 400 °C). The samples were systematically characterized for vibrational, structural, optical, and Electrochromic (EC) properties by using Raman, XRD, Uv-Vis spectrometer, and Electrochemical analyzer respectively. XRD analysis reveals that RT-deposited samples show amorphous nature and pre & post-annealed samples show a crystalline nature for both pO2. Optical transmittance was higher at RT-deposited samples at 50 mA (94% & 92%) and lower at 100 mA (87% & 85%) at the wavelength of 600 nm for both pO2. From CV analysis higher cathodic peak current density was observed in RT-deposited samples at 50 mA (−6.49 mAcm−2 & -13.80 mAcm−2) and lower at 100 mA (−5.25 mAcm−2 & -12.88 mAcm−2) for both pO2. The diffusion coefficient was observed at a higher target current at 100 mA (1.06 × 10−7 cm2/s & 9.20 × 10−8 cm2/s). For annealed samples optical and EC properties were decreased for both pO2.
•Deposition tungsten oxide thin films using DC Magnetron Sputtering.•Deposition of tungsten oxide thin films at different oxygen partial pressure 4 × 10−4 mbar and 8 × 10−4 mbar.•Studied optical and electrochemical properties of both oxygen partial pressure.