Effect of growth temperature on the structural and electrical properties of ZrO₂ films fabricated by atomic layer deposition using a CpZr[N(CH₃)₂]₃/C₇H₈ cocktail precursor

The effect of growth temperature on the atomic layer deposition of zirconium oxide (ZrO₂) dielectric thin films that were fabricated using a CpZr[N(CH₃)₂]₃/C₇H₈ cocktail precursor with ozone was investigated. The chemical, structural, and electrical properties of ZrO₂ films grown at temperatures from 250 to 350 °C were characterized. Stoichiometric ZrO₂ films formed at 250-350 °C with an atomic ratio of O to Zr of 1.8-1.9 and a low content of carbon impurities. The film formed at 300 °C was predominantly the tetragonal crystalline phase, whereas that formed at 350 °C was a mixture of tetragonal and monoclinic phases. Electrical properties, such as capacitance, leakage current, and voltage linearity of TiN/ZrO₂/TiN capacitors fabricated using the thin ZrO₂ films grown at different temperatures were compared capacitor applications. The ZrO₂ film grown at 300 °C exhibited low impurity content, predominantly tetragonal crystalline structure, a high dielectric permittivity of 38.3, a low leakage current of below 10^-7 A/cm² at 2 V, and low-voltage linearity.