Sputtered ferroelectric thin films of lead Germanate

Abstract
Lead Germanate Pb5Ge011 and some of its substitutional derivatives such as Pb5(Ge1-xSix)3011 1 or (Pb5-xBax)Ge3011 are of interest because of their pyroelectric 2 and electrooptic 3 behaviour. By reactive de-sputtering we have grown thin films of Lead Germanate on several substrates. Electron probe microanalysis (EPMA) and X-ray investigations have been performed. They demonstrate that it is possible to grow stoichiometric films exhibiting the structure of the bulk. Special heat treatments have lead to a preferential straightening of the [001]-axis normal to the substrate's surface. The dielectric properties of the films are well correlated to those known from ceramics and single crystals.