Rare earth titano-silicates for high k gate dielectric applications

The present paper explores the properties of rare earth titano-silicates compounds for high k applications. RE2Ti2SiO9 (RE=La, Pr and Nd) ceramic compounds were prepared using conventional solid state reaction route. Its structural, dielectric, optical and thermal properties were investigated. It was found that these materials possess a high dielectric constant in the range of 20–34 at room temperature, which is greater than that of HfO2. The UV Visible absorption spectra indicates reasonably large band gap of above 5 eV. Further these compounds also have low coefficient of thermal expansion of less than 9 ppm/°C.