Abstract
ZnO seed layer were grown on glass substrates by mist-atomization, which then used as ZnO template for the second step of deposition method. Next, ZnO thin films have been deposited onto ZnO seeded template prepared earlier with various precursor concentrations by solution-immersion method. The ZnO seeded templates were immersed in different concentrations of starting materials; which are zinc nitrate hexahydrate and HMTA. The precursor concentrations were varied from 0.05, 0.10, 0.20 and 0.40 M. The ZnO seed layer which undergoes mist-atomization only, denoted as 'MA only' is prepared for comparison studies to the other thin films. The properties of the thin films were examined by photoluminescence (PL) spectrophotometer, Raman spectrophotometer, and ultraviolet-visible (UV-vis) spectrophotometer. From the PL measurement, it shows that 0.40 M sample owned the highest UV emission and from Raman measurements, it was found that the sample immersed in 0.40 M precursor having high crystal quality. From UV-Vis measurements, sharp UV emission at similar to 378 nm is observed and 0.40 M ZnO thin film shows a better absorption properties. The optical bandgap energy (E-g) of the films was evaluated. The optical bandgap energy obtained by Tauc's plot of thin film with precursor concentration of 0.40 M has the smallest value (3.227 eV). The energy bandgap energy of the resulting ZnO films was found to be strongly influenced by the precursor concentrations.