ZnO doped with Bismuth in case of in-phase behavior for solar cell application

Abstract

Zinc Oxide (ZnO) nanostructure thin films doped with bismuth atoms were initially achieved by spin coating preparation from zinc acetate gel on the fused quartz substrate. The optical and structural properties have been preliminary studied in order to obtain more understanding the optimized factors for transparent conductive oxides (TCOs) of thin film solar cell. The optical transmittance was higher than 90% in the visible range for all films. In addition, the optical band gap of the prepared films calculated by Tauc plot showed the change of lightly blue shift but no significantly changed with increasing of Bi doping concentration. The glancing incident X-ray diffraction result showed that the Bi doped in ZnO nanostructure thin films after annealing have polycrystalline hexagonal wurtzite structure and good preferential orientation along c-axis. This chemical characterization indicated that in-phase behavior occurred in low Bi dopant content between 0.2 - 1.0 at.% Bi content, hence 1 atomic percentage of Bi content was uppermost to obtain preferential orientation in this study. However, the quality of the films surface was improved due to the larger number of coating layers but the electrical properties was improved. The tentative study in term of electrical behavior was investigated for application in TCO film of solar cell. The electrical property showed that more multi ZnO layers affected on an increase in the electrical conductivity of the films.