Crystallinity Effect on Electrical Properties of PEALD–HfO<sub>2</sub> Thin Films Prepared by Different Substrate Temperatures

oleh: Xiao-Ying Zhang, Jing Han, Duan-Chen Peng, Yu-Jiao Ruan, Wan-Yu Wu, Dong-Sing Wuu, Chien-Jung Huang, Shui-Yang Lien, Wen-Zhang Zhu

Format: Article
Diterbitkan: MDPI AG 2022-11-01

Deskripsi

Hafnium oxide (HfO<sub>2</sub>) thin film has remarkable physical and chemical properties, which makes it useful for a variety of applications. In this work, HfO<sub>2</sub> films were prepared on silicon through plasma enhanced atomic layer deposition (PEALD) at various substrate temperatures. The growth per cycle, structural, morphology and crystalline properties of HfO<sub>2</sub> films were measured by spectroscopic ellipsometer, grazing-incidence X-ray diffraction (GIXRD), X-ray reflectivity (XRR), field-emission scanning electron microscopy, atomic force microscopy and x-ray photoelectron spectroscopy. The substrate temperature dependent electrical properties of PEALD–HfO<sub>2</sub> films were obtained by capacitance–voltage and current–voltage measurements. GIXRD patterns and XRR investigations show that increasing the substrate temperature improved the crystallinity and density of HfO<sub>2</sub> films. The crystallinity of HfO<sub>2</sub> films has a major effect on electrical properties of the films. HfO<sub>2</sub> thin film deposited at 300 °C possesses the highest dielectric constant and breakdown electric field.