Resumen de Water effect in the synthesis of nanostructured thin films of HfO2 deposited by the ultrasonic spray pyrolysis technique

R. Vázquez Arreguín, A. González Cisneros, M. García Rocha, G. Juárez-Gracia, L. Mariscal Becerra, A.A. Durán Ledezma

• HfO_(2) thin films are proposed as a high-k dielectric gate, especially for the fabrication of ultra-large-scale integration systems. The effect of adding deionized water during the synthesis of HfO_(2) thin films on its structural and dielectric properties is reported. The study of nanostructured HfO_(2) thin films deposited on crystalline silicon wafers is made by applying the ultrasonic spray pyrolysis (USP) technique. For the synthesis of hafnium oxide thin films, hafnium acetylacetonate was dissolved in dimethylformamide as a hafnium source material. The substrate temperature was varied from 400◦C and up to 550◦C in increments of 50◦C and adding deionized water during the process, favoring films with well-defined monoclinic structures. The thin films presented a nanostructured morphology and a rugosity with a mínimum value of 0.45 nm. Refractive index values between 1.87 and 2.02 were obtained with an average thickness of ∼21 nm. The carbon and O-H bonds decrease considerably, adding deionized water during the deposit. The electrical characterization revealed that the films deposited with deionized water have a high dielectric constant with a maximum value of 14.4, demonstrating that this addition during deposition allows thinner films with good dielectric properties.