Effect of cobalt doping on the microstructural, optical and electrical properties of SnO2 thin films by sol-gel spin coating technique

• Published in: Physica. B, Condensed matter Vol. 624; p. 413432
• Main Authors: Soumya, S.S., Xavier, T.S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.2022; Elsevier BV
• Subjects: Band gap; Chemical synthesis; Cobalt; Cobalt doped tin oxide; Crystallites; Electrical properties; FESEM; Indium tin oxides; Optical and electrical properties; Optical properties; Sol-gel process; Sol-gel processes; Spin coating; Thin films; Tin; Tin dioxide; Tin oxides; Thin films; Optical and electrical properties; Sol-gel process; Cobalt doped tin oxide; Spin coating; FESEM
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2021.413432

Undoped and cobalt doped tin oxide thin films were successfully synthesized by using the sol-gel spin coating technique and post annealed at 600 °C. XRD analysis reveals that all the prepared tin oxide thin films were polycrystalline in nature and crystallizes with tetragonal rutile structure with average crystallite size ranges from 4.39 nm–11.47 nm. SEM analysis shows that the nano sized particles were uniformly dispersed in the prepared thin films. The elemental composition was found out by using EDAX analysis and found that the tin oxide thin films contain Co, Sn and oxygen. The optical band gap values were calculated using Tauc plot and are ranging from 2.28 eV–3.40 eV. FTIR analysis shows that the prepared thin films contain Sn–O–Sn, Sn–O, H–O–H, C–O and Sn–OH vibrations. Electrical studies reveal that the resistivity of all the films was very low and are ranging from 1.1556 × 10−3 Ω-m - 1.7642 × 10−3 Ω-m. •This paper discuss the influence of cobalt doping on the microstructural, optical and electrical properties of tin oxide thin films prepared by sol-gel spin coating technique.•5 wt% cobalt doped tin oxide thin films shows lowest value of stress, dislocation density and resistivity.•The microstructural, optical and electrical properties enable 5 wt% cobalt doped tin oxide films for optoelectronic and solar cell applications.