ZnO Films with Very High Haze Value for Use as Front Transparent Conductive Oxide Films in Thin-Film Silicon Solar Cells

We successfully increased the haze value of zinc oxide (ZnO) films fabricated using metal-organic chemical vapor deposition (MOCVD) by conducting glass-substrate etching before film deposition. It was found that with increasing the glass treatment time, the surface morphology of ZnO films changed from conventional pyramid-like single texture to greater cauliflower-like multi texture. Further, the rms roughness and the haze value of the films increased remarkably. Using ZnO films with a high haze value as front transparent conductive oxide (TCO) films in hydrogenated microcrystalline silicon (mu c-Si:H) solar cells, we improved the quantum efficiency of these cells particularly in the long-wavelength region. (C) 2010 The Japan Society of Applied Physics