Preparation of ferroelectric thin films for Si-based devices

Abstract

Lead titanate (PbTiO₃) thin films have been prepared on titanium dioxide coated silicon wafers by chemical vapor deposition (CVD). The pure PbTiO₃ thin films were deposited by controlling the experimental conditions. The gas phase reaction of TiO₂ occurred by exceeding the critical value of titanium input fraction at constant oxygen partial pressure. Strontium titanate (SrTiO₃) thin films have been prepared on p-type silicon wafers by radio frequency (RF) magnetron sputtering. The SrTiO₃ thin film was polycrystalline and the Sr/Ti ratio of this film was 0.91. The SrTiO₃ thin films contain three regions, an external surface layer, a main layer and an interfacial layer. The stoichiometric SrTiO₃ thin film was obtained by using the SrO excess target. The SrTiO₃ film annealed at 600[ddot]C has an ideal capacitance-voltage (C-V) curve and maximum effective dielectric constant.