Optimal Process Design for Wake-Up Free Hf[sub.0.5]Zr[sub.0.5]O[sub.2] Ferroelectric Capacitors: Toward Low-Power Devices with Enhanced Ferroelectric Performance

• Published in: Electronics (Basel) Vol. 13; no. 15
• Main Authors: Wang, Hui, Qi, Jiabin, Xie, Xinyu, Liu, Zongfang, Wu, Wenhao, Lee, Choonghyun
• Format: Journal Article
• Language: English
• Published: MDPI AG 01.08.2024
• Subjects: Capacitors; Complementary metal oxide semiconductors; Electronic components industry
• ISSN: 2079-9292; 2079-9292
• DOI: 10.3390/electronics13152895

Ferroelectric hafnium and zirconium oxides have recently garnered significant attention due to their potential applications in in-memory computing. In this study, we present an optimized process design for a wake-up free 15 nm thick Hf[sub.0.5]Zr[sub.0.5]O[sub.2] (HZO) ferroelectric capacitor by fine-tuning the dual-oxygen process and incorporating oxygen annealing after post-metallization annealing (PMA). The optimized approach resulted in a competitive polarization of 28.6 μC/cm[sup.2], consistently exceeding 25 μC/cm[sup.2] at 3 V after 2 × 10[sup.7] cycles, showcasing a current density of 3.2 mA/cm[sup.2] at 2 V after 10[sup.5] cycles. The synergistic effect of oxygen vacancies and grain properties (grain size, phase proportion) enables competitive ferroelectric polarization at lower voltages, while the generation of WO[sub.x] near the top electrode and increased grain size further ensure the reliability of the HZO ferroelectric capacitor. This work presents innovative perspectives for the development of non-volatile devices characterized by low leakage current and low power consumption.