Aging effects of the precursor solutions on the properties of spin coated Ga-doped ZnO thin films

• Main Authors: Serrao Felcy Jyothi, Dharmaprakash, S M
• Format: Conference Proceeding
• Language: English
• Subjects: ABSORPTION; ACETATES; AGING; Coating effects; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DOPED MATERIALS; Film thickness; GALLIUM; GALLIUM IONS; GALLIUM NITRATES; GLASS; Glass substrates; GRAIN ORIENTATION; GRAIN SIZE; Morphology; OPTICAL PROPERTIES; POLYCRYSTALS; PRECURSOR; Precursors; SOL-GEL PROCESS; Sol-gel processes; Spin coating; SPIN-ON COATING; SUBSTRATES; SURFACES; THIN FILMS; Transmittance; Wurtzite; X-RAY DIFFRACTION; Zinc acetate; Zinc coatings; Zinc oxide; ZINC OXIDES
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.4917971

In this study, gallium doped zinc oxide thin films (GZO) were grown on a glass substrate by a simple sol-gel process and spin coating technique using zinc acetate and gallium nitrate (3at%) as precursors for Zn and Ga ions respectively. The effects of aging time of the precursor solution on the structural and optical properties of the GZO films were investigated. The surface morphology, grain size, film thickness and optical properties of the GZO films were found to depend directly on the sol aging time. XRD studies reveal that the films are polycrystalline with a hexagonal wurtzite structure and show the c-axis grain orientation. Optical transmittance spectra of all the films exhibited transmittance higher than about 82% within the visible wavelength region. A sharp fundamental absorption edge with a slight blue shifting was observed with an increase in sol aging time which can be explained by Burstein-Moss effect. The result indicates that an appropriate aging time of the sol is important for the improvement of the structural and optical properties of GZO thin films derived from sol-gel method.