Structure and electrical characterization of amorphous ErSiO films deposited by rf magnetron sputtering on Si (001)

Abstract

Amorphous ErSiO films have been fabricated on p-type Si (001) substrates using rf magnetron sputtering technique. X-ray diffraction, high-resolution transmission electron microscopy, and atomic force microscopy were employed to investigate the samples. It is found that ErSiO film exhibits a flat surface, a sharp interface and superior electrical properties after post-deposition annealing in O2 ambience for 30 min at 450°C. The effective dielectric constant of the film is measured to be 14.2, and the effective oxide thickness reaches 1.9 nm, with a low leakage current density of 1.1×10−4 A/cm2 at an electric field of 1 MV cm−1 after annealing at 450°C. The obtained characteristics make the amorphous ErSiO films a promising substitute for SiO2 as a high-k gate dielectric.