Blue Shift of Optical Band Gap in ZnO Thin Film Grown by Spin Coating Process
[Santhosh Prabhu,Dr. Dhananjaya Kekuda] Volume 1: Issue 2, April 2014
Abstract:-Optical band gap of ZnO thin films deposited on glass substrate by spin coating process was studied. The optical band gap of as-grown ZnO blue shifted from 3.11eV to 3.69 eV as the annealing temperature decreased from 300 to 100 °C. Also observed that there is a variation in the transmittance of ZnO thin film. X-ray diffraction measurements showed that samples deposited at 1000C, 2000C and 3000C consisted of amorphous phases without any prominent diffraction peaks. The AFM images showed that there is a decrease in the grain size, which is the evidence for the decrease in the transmittance.
Index Terms:-Spin coating, UV-visible, XRD, AFM, Optical properties.
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