Zinc oxide (ZnO) thin films were prepared chemically on silicon substrates by immersing the substrates in an aqueous solution containing zinc nitrate and dimethylamineborane. Chemical deposition enables film formation for electronic devices with arbitrary shapes, such as spherical silicon solar cells. An increase in zinc nitrate concentration and solution temperature resulted in columnar growth of high density hexagonal crystals, yielding a high refractive index. The lowest reflectance of the ZnO/Si of less than 1% was achieved by the optimization of deposition conditions, indicating that the film can be utilized as an antireflective coating on spherical silicon solar cells. (c) 2006 Elsevier B.V All rights reserved.