Effect of anionic bromine doping on the structural, optical and electrical properties of spray-pyrolyzed SnO2 thin films

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Vol. 282; p. 115756
• Main Authors: Fernandes, Jean Maria, Suresh, G., Muniramaiah, Reddivari, Maharana, Gouranga, Geetha, A., Kovendhan, M., Venkateswaran, C., Paul Joseph, D.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.08.2022; Elsevier BV
• Subjects: Activation energy; Bromine; Bromine-doped SnO2; Crystallites; Doped films; Doping; Electrical properties; Figure of merit; High temperature; Ionic conductivity; Optical properties; Optoelectronic devices; Spray-pyrolysis; Temperature dependence; Temperature-dependent electrical resistivity; Thin films; Tin dioxide; Transparent conducting layer; Temperature-dependent electrical resistivity; Bromine-doped SnO2; Transparent conducting layer; Spray-pyrolysis; Activation energy; Ionic conductivity
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2022.115756

•Facile and cost-effective spray pyrolysis is used to deposit Br-doped SnO2 thin films.•Br doping leads to low surface free energy of the thin films.•Increase in surface roughness is attributed to subtle deviation in deposition parameters.•Activation energy in the high temperature regime decreases with Br doping.•Higher figure of merit is obtained for Br-doped SnO2 film. The effect of 5 wt% Br incorporation on the structural, morphological, optical and temperature-dependent electrical properties of spray-deposited SnO2 films is explored by employing various characterization techniques. Br dopant acts as an ionic species that is expected to significantly improve the optoelectronic properties of SnO2. Marginal increase in crystallite size is observed with Br doping. Transmittance is higher for Br-doped film and optical band gap increases from 3.03 eV to 3.11 eV, indicating its tunability for optoelectronic device requirements. Activation energy in high-temperature regime up to 343 K decreases from 0.415 eV to 0.349 eV with Br doping, indicating improved conductivity. Significant reduction in resistivity from 19.8 Ω cm to 7.36 Ω cm is observed upon doping. The Br-doped SnO2 sample shows higher figure of merit in comparison to that of undoped SnO2, indicating its potential as an effective alternative transparent conducting layer for appropriate optoelectronic applications.