Electrodeposition of ZnO Thin Films with Controllable Impurities and Microstructures

To enhance the conductivity and reduce the surface roughness of ZnO films, electrodeposition of ZnO films on the ITO substrate had been studied for the application of inverted organic solar cells. ZnO films with the grain size range from 0.4 to 2 μm had been fabricated by varying the temperature, ion concentration and deposition potentials. Moreover, ZnO films with the impurity energy level of 2.28±0.20 eV origin from the oxygen vacancy, had been found in the PL emission. It is found that as the applied potential went more negative, the concentration of the oxygen vacancies increased, and the emission peak of the impurity level had higher intensity. By changing the ion concentration and temperature of the electrolyte, the controllable microstructure and impurity levels of ZnO thin films had been achieved.