Transparent conductive Ga-doped ZnO films and their application in dye-sensitized solar cells

This paper presents transparent conductive Ga-doped ZnO (GZO) films and their application in dye-sensitized solar cells (DSSCs). The GZO thin films were deposited on glass substrates by using pulsed laser deposition (PLD). In order to find the optimal condition, we carried out the deposition at various oxygen pressures and temperatures. The structural, electrical, and optical properties of the GZO thin films were investigated. The c-axis-oriented polycrystalline GZO films were obtained under all conditions. The GZO films deposited under the optimal conditions showed a low sheet resistance of 6.87 Ω/sq and a high optical transmittance of ∼85%, which are suitable values for DSSCs. The DSSCs were successfully fabricated based on the prepared GZO films with a thin TiO2 blocking layer. The fabricated DSSCs with the GZO transparent electrodes showed a conversion efficiency of 3.96%.