Effects of growth parameters on HfO2 thin-films deposited by RF Magnetron sputtering

Abstract

Hafnium oxide is well known and extensively studied material for electronic and optical applications. In this work, HfO2 films have been investigated at different radio frequency (RF) powers to elucidate the grain growth, structural and optical properties. Also, the MATLAB coded envelope method was utilized and tested to extract the optical properties more efficiently. As a result, the film thickness and grain size increase linearly with power. In addition, the grain size increases from 35 nm to 287 nm with RF power. These values are more or less consistent with Rutherford Backscattering Spectroscopy (RBS), optically derived film thickness. An interlayer is formed between film and substrate, and its thickness increases from 4 to 10 nm with deposition power. The transformation from amorphous to polycrystalline nature has been observed with the variation of RF power. The different kinds of oxygen defects were found in films obtained by different deposition rates, which is evident from photoluminescence measurement. This study will be utilized to understand films’ deposition parameter dependant structural and optical properties and understand their underlying physics.