Highly textured spray-deposited SnO2:F films with high haze for solar cells

Abstract

Highly textured F-doped SnO2 (FTO) films with appropriate haze, high transparency and low resistance have been deposited on quartz glass substrates by spray pyrolysis technique at different substrate temperatures from 380 °C to 630 °C. The results show that all FTO films with pyramidal-shape grains are polycrystalline with cassiterite tetragonal structure and exhibit an obviously (200) preferred orientation. When the substrate temperature is 530 °C, the dislocation density of FTO films reaches a minimum value of 1.90 × 1015 line/m2, while the film thickness and root-mean-square roughness reach the maximum values of 613 nm and 32.3 nm, respectively. Highly textured FTO films sprayed at 530 °C exhibit the lowest turn on voltage of 1.95 eV and the optimal comprehensive optoelectrical performance with the high transmittance of 83.78%, low sheet resistance of 8.4 Ω/□ and high haze of 12.69%, which are the promising candidates as the transparent conductive oxide front electrode for film solar cells.