${\mathrm{TiO}}_2$ thin films with high dielectric constants (83–100) were grown on a Ru electrode at a growth temperature of 250 °C using the atomic-layer deposition method. The as-deposited films were crystallized with rutile structure. Adoption of ${\mathrm{O}}_3$ with a very high concentration $(400\mathrm{g}∕{\mathrm{m}}^3)$ was crucial for obtaining the rutile phase and the high dielectric constant. The leakage current density of a ${\mathrm{TiO}}_2$ film with an equivalent oxide thickness of 1.0–1.5 nm was ${10}^{-6}–{10}^{-8}\mathrm{A}∕{\mathrm{cm}}^2$ at $\pm 1\mathrm{V}$ . All these electrical properties were obtained after limited postannealing where the annealing temperature was $<500°\mathrm{C}$ , which is crucial to the structural stability of the Ru electrode. Therefore, these ${\mathrm{TiO}}_2$ films are very promising as the capacitor dielectrics of dynamic random access memories. ${\mathrm{TiO}}_2$ films grown on a bare Si wafer or Pt electrode by the same process had anatase structure and a dielectric constant of $\sim 40$ .

<mml:math display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">Al</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>Al2O3 films were deposited by atomic layer deposition (ALD) using trimethylaluminum and <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:math>O3 as precursor and oxidant, respectively, at growth temperatures ranging from room temperature to <mml:math display="inline"><mml:mrow><mml:mn>300</mml:mn><mml:mo>°</mml:mo><mml:mi mathvariant="normal">C</mml:mi></mml:mrow></mml:math>300°C on Si(100) substrates. Growth rate and refractive index of the <mml:math display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">Al</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>Al2O3 films decreased from <mml:math display="inline"><mml:mrow><mml:mn>0.20</mml:mn><mml:mspace width="0.3em"></mml:mspace><mml:mtext>to</mml:mtext><mml:mspace width="0.3em"></mml:mspace><mml:mn>0.08</mml:mn><mml:mspace width="0.3em"></mml:mspace><mml:mi>nm</mml:mi><mml:mo>∕</mml:mo><mml:mtext>cycle</mml:mtext></mml:mrow></mml:math>0.20to0.08nm∕cycle and increased from 1.52 to 1.65, respectively, with increasing growth temperature. The dielectric constant slightly increased from 6.8 to 8 with increasing growth temperature in the same temperature range. <mml:math display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">Al</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>Al2O3 films grown using <mml:math display="inline"><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:math>O3 as oxidant show a smaller hysteresis, lower leakage current density, and higher breakdown field strength compared to those using <mml:math display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">H</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:mi mathvariant="normal">O</mml:mi></mml:mrow></mml:math>H2O as oxidant at the same growth temperature. X-ray photoelectron spectroscopy showed that the films grown at lower temperatures have a smaller bandgap energy. The <mml:math display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">Al</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>Al2O3 films grown at a temperature as low as <mml:math display="inline"><mml:mrow><mml:mn>100</mml:mn><mml:mo>°</mml:mo><mml:mi mathvariant="normal">C</mml:mi></mml:mrow></mml:math>100°C showed reasonable dielectric properties for dielectric film applications on flexible substrates.