A p-i-n doped pc-silicon thin film grown by means of hot wire chemical vapour deposition (HW CVD) on a zinc oxide film has been investigated by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). The structure of both layers, the ZnO substrate layer as much as the silicon thin film and the chemical composition at the interface were the subjects of our investigations. We found that a file of pure silicon with a thickness of about 5 nm covers the substrate surface. A plausible model for getting information on the wavyness of the interface ZnO/pc-Si and the thickness of this pure Si-layer was developed.