To systematically study the crystallization process of electron-beam evaporated amorphous silicon on ZnO:Al-coated glass for polycrystalline silicon thin film solar cells, transmission electron microscopy and optical microscopy were employed. A time and temperature dependent analysis allowed the individual investigation of the growth and nucleation processes. The growth velocities of Si-crystals on ZnO:Al and SiN-coated glass were found to be identical within the investigated temperature regime of 500-600 °C. However, with a high steady state nucleation rate and a low activation energy, the nucleation process of Si on ZnO:Al-coated glass has shown to differ significantly from nucleation on glass. © 2009 American Institute of Physics.