Natively textured surface hydrogenated gallium-doped zinc oxide transparent conductive thin films with buffer layers for solar cells

Natively textured surface hydrogenated gallium-doped zinc oxide (HGZO) thin films have been deposited via magnetron sputtering on glass substrates. These natively textured HGZO thin films exhibit rough pyramid-like textured surface, high optical transmittances in the visible and near infrared region and excellent electrical properties. The experiment results indicate that tungsten-doped indium oxide (In2O3:W, IWO) buffer layers can effectively improve the surface roughness and enhance the light scattering ability of HGZO thin films. The root-mean-square roughness of HGZO, IWO (10nm)/HGZO and IWO (30nm)/HGZO thin films are 28, 44 and 47nm, respectively. The haze values at the wavelength of 550nm increase from 7.0% of HGZO thin film without buffer layer to 18.37% of IWO (10nm)/HGZO thin film. The optimized IWO (10nm)/HGZO exhibits a high optical transmittance of 82.18% in the visible and near infrared region (λ~400–1100nm) and excellent electrical properties with a relatively low sheet resistance of 3.6Ω/□ and the resistivity of 6.21×10−4Ωcm.