Self-polarized Pb(Ti,Zr)O-3 thin films deposited under lead enriched conditions by multi-target reactive sputtering at low substrate temperatures are characterized by tetravalent B-site occupation of excess lead. The imaginary part of the dielectric constant of such films shows a relaxor-like behavior. Evidence of a Ph2+/Pb4+ mixed valence is given by the temperature and frequency dependence of the ac conductivity. PbO volatility starts to deplete the growing film at a critical temperature of 500 degrees C and Pb4+ formation disappears.