Modification of optical and electrical properties of sol-gel-derived TiO2-doped ZrO2 gate dielectrics by annealing temperature

Abstract In this letter, annealing temperature dependence on the structure, band gap energy and electrical properties of TiO 2 doped ZrO 2 gate dielectrics deposited by sol-gel method at low temperature were systemically investigated. The crystalline temperature of TiO 2 doped ZrO 2 is up to 600 °C. The transmittance and band gap value of the ZrTiO x film were about 75% and 4.0 eV, respectively. 300 °C-annealed ZrTiO x MOS capacitor with high dielectric constant of 34.9, a small hysteresis value of 0.004 and low leakage current density of 2.7 × 10 −4 A/cm 2 were obtained. The dominant conduction mechanisms of Al/ZrTiO 4 / n -Si MOS structures were schottky emission and ohmic conduction in the low electric field and direct tunneling in the high electric field. As a result, it can be concluded that sol-gel derived ZrTiO x gate dielectric displays potential application as is a promising candidate in future MOS electronic devices.