Crystallization kinetics in high rate electron beam evaporated poly Si thin film solar cells on ZnO Al

The microstructure and crystallization kinetics of electron beam evaporated Si on ZnO Al coated glass for polycrystalline solar cells was studied by electron backscatter diffraction and optical microscopy at various deposition temperatures. A time dependent analysis of the dynamics of the crystallization allowed for the individual determination of growth and nucleation processes. The nucleation process of Si on ZnO Al was found to be influenced by a variation of the deposition temperature of the amorphous Si in a critical temperature regime of 200 amp; 730;C to 300 amp; 730;C. The nucleation rate decreased significantly with decreasing deposition temperature, while the activation energy for nucleation increased from 2.9 eV at a deposition temperature of 300 amp; 730;C to 5.1 eV at 200 amp; 730;C, resulting in poly Si which comprised grains with features sizes of several amp; 956;