Correlation of film thickness to optical band gap of Sol-gel derived Ba0.9Gd0.1TiO3 thin films for optoelectronic applications
School of Microelectronic Engineering, University Malaysia Perlis, Pauh Putra Campus, 02600 Arau, Perlis Malaysia
2 AMBIENCE UniMAP, Kompleks Kilang SME Bank, Kawasan Perindustrian Kuala Perlis, 02000 Kangar, Perlis Malaysia
* Corresponding author: email@example.com
Published online: 22 November 2017
Ba0.9Gd0.1TiO3 thin films have been fabricated on SiO2/Si and fused silica by sol-gel method. The films are prepared through a spin coating process and annealed at 900 °C to obtain crystallized films. The effect of film thickness on the microstructure and optical band gap has been investigated using X-ray diffractometer, atomic force microscope and ultraviolet-visible spectroscopy, respectively. XRD patterns confirm that the films crystallized with tetragonal phase perovskite structure. The films surface morphology is analysed through amplitude parameter analysis to find out that the grain size and surface roughness are increased with the increase of films thickness. The transmittance and absorbance spectra reveal that all films exhibit high absorption in UV region. The evaluated optical band gap is obtained in the range of 3.67 - 3.78 eV and is found to be decreased as the thickness increase.
© The Authors, published by EDP Sciences, 2017
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