FERROELECTRIC MIM AND MOS STRUCTURE OF LASER DEPOSITED (Sr,,Ba,~8)Ti0, THIN FILMS

The laser ablation technique has been applied to synthesize the (Sr,,Ba,,)TiO, thin fims. Substrate temperature and chamber oxygen pressure were observed to affect the characteristics of the films most prominently. The metal-insulator-metal (MIM) structqre of the films deposited on Pt-coated Si-substrates, possesses better ferroelectric properties than those of the metal-oxide-semiconductor (MOS) structure, as demonstrated by hysteresis loops of remanence p,=1.56 pC/cmz and coercivity Ec=13.5 kV/cm. The ferroelectricity of MIM structure is also indicated by butterfly C-V characteristics while that of MOS structure is depicted by hysteresis c-V curves. The charge-discharge test reveals that the effective dielectric constant of the ferroelectric (Sro,Bao.8)Ti0, thin films can reach a value as high as E ,=788.