High Dielectric Constant of RF-Sputtered HfO₂ Thin Films

Abstract

Hafnium dioxide (HfO 2 ) thin films are deposited on indium-tin-oxide (ITO)-coated glass substrates by the radio-frequency (RF) sputtering method using a HfO 2 sintered target. The deposition conditions, dielectric loss and dielectric constant of HfO 2 films before and after heat treatment are studied. The best deposition conditions for HfO 2 films are RF power 200 W, substrate temperature 100°C and sputtering gas pure Ar. The maximum dielectric constants are about 150 and 45 with 1 kHz signal excitation before and after annealing, respectively. They are higher than any ever reported.