Properties of ZnO:Al films on polymer substrates by low temperature process

Transparent electrode ZnO:Al(AZO)films were deposited on a PES (polyethersulfone) polymer substrate for thin film solar cells applications. A PES substrate with a thickness of 0.2mm and transmittance > 90% in the visible range was used because it is light weight and can deform easily. AZO thin films were prepared at a fixed DC power, $PO_2\;=\;P(O_2)/[P(O_2)\;+\;P(Ar)]$, and various substrate temperatures. The properties of AZO thin films were examined by X-ray diffraction, UV/VIS spectroscopy, four-point probe, Hall measurements, and field emission scanning electron microscopy. The lowest resistivity of all the films was $4.493\;{\times}\;10^{-4}\;[\Omega-cm]$ and the transmittance was > 80% in the visible range.