Investigation on polarization characteristics of ferroelectric memories with thermally stable hafnium aluminum oxides. (August 2019)

• Record Type: Journal Article
• Authors: Chang, Tun-Jen; Liu, Chien; Fan, Chia-Chi; Hsu, Hsiao-Hsuan; Chen, Hsuan-Han; Chen, Wan-Hsin; Fan, Yu-Chi; Lee, Tsung-Ming; Lin, Chien-Liang; Ma, Jun; Zheng, Zhi-Wei; Cheng, Chun-Hu; Wang, Shih-An; Chang, Chun-Yen
• Is Part Of: Vacuum. Volume 166(2019)
• Page Start: 11
• Page End: 14
• Publication Date: 2019-08
• Subjects: Ferroelectric -- HfAlOx -- Thermal stability -- Endurance cycling -- Domain pinning; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2019.04.045
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: In this work, we successfully demonstrated the 9.6-nm-thick HfAlOx ferroelectric memory using light aluminium doping of 6.5% to form ferroelectric orthorhombic phase. Compared to ferroelectric HfZrOx film with zirconium diffusion issue, the HfAlOx film showed excellent thermal stability under high temperature annealing. Besides, the ferroelectric HfAlOx also exhibited robust polarization characteristics under endurance cycling test. A >10 6 stressed cycles with 4 MV/cm can be measured and a long endurance was sustained over 5 × 10 7 cycles under 3.6 MV/cm. Therefore, the HfAlOx film showed the great promise for integrating in high performance ferroelectric memory with thermal budget concerns. Highlights: Thermal stability, dynamic leakage issue and endurance of HfO2 -based memory were investigated. Less amount of aluminum doping into HfO2 was favorable to reduce dynamic leakage during ferroelectric switching. A long and stable endurance can be sustained over 5 × 107 cycles under 3.6 MV/cm in HfAlOx memory. Thermally-stable HfAlOx memory showed the potential for the integration with modern gate-first CMOS process.