Lead titanate coatings on optical fibers deposited by reactive magnetron sputtering

A Ti/Pt/PbTiO3/Au multilayer thin film structure has been deposited onto st andard telecommunication optical fibers. A reactive magnetron sputter depos ition technique at high temperature was used to obtain in situ crystallized PbTiO3 thin films with the perovskite structure. PbTiO3 layers with a cons tant thickness of about 0.81 +/- 0.05 mu m were obtained over a 5 cm length of fiber, but both microstructure and phase formation vary widely along th e fiber length. A dielectric constant of 210 +/- 13 and dielectric loss of 0.07 were measured for the phase pure PbTiO3 coated section of fiber. Varia tions in the coating properties along the fiber can clearly be related to t he temperature distribution occurring in the fabrication process.