Excellent resistive switching properties of atomic layer-deposited Al2O3/HfO2/Al2O3 trilayer structures for non-volatile memory applications

Lai-Guo Wang; Xu Qian; Yan-Qiang Cao; Zheng-Yi Cao; Guo-Yong Fang; Ai-Dong Li; Di Wu

doi:10.1186/s11671-015-0846-y

Excellent resistive switching properties of atomic layer-deposited Al2O3/HfO2/Al2O3 trilayer structures for non-volatile memory applications

Nanoscale Res Lett. 2015 Mar 19:10:135. doi: 10.1186/s11671-015-0846-y. eCollection 2015.

Authors

Lai-Guo Wang¹, Xu Qian², Yan-Qiang Cao², Zheng-Yi Cao², Guo-Yong Fang², Ai-Dong Li², Di Wu²

Affiliations

¹ National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Sciences, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 22 Hankou Road, Nanjing, 210093 People's Republic of China ; Anhui Key Laboratory of Functional Coordination Compounds, School of Chemistry and Chemical Engineering, Anqing Normal University, 128 Linghu South Road, Anhui, 246011 People's Republic of China.
² National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Sciences, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 22 Hankou Road, Nanjing, 210093 People's Republic of China.

Abstract

We have demonstrated a flexible resistive random access memory unit with trilayer structure by atomic layer deposition (ALD). The device unit is composed of Al2O3/HfO2/Al2O3-based functional stacks on TiN-coated Si substrate. The cross-sectional HRTEM image and XPS depth profile of Al2O3/HfO2/Al2O3 on TiN-coated Si confirm the existence of interfacial layers between trilayer structures of Al2O3/HfO2/Al2O3 after 600°C post-annealing. The memory units of Pt/Al2O3/HfO2/Al2O3/TiN/Si exhibit a typical bipolar, reliable, and reproducible resistive switching behavior, such as stable resistance ratio (>10) of OFF/ON states, sharp distribution of set and reset voltages, better switching endurance up to 10(3) cycles, and longer data retention at 85°C over 10 years. The possible switching mechanism of trilayer structure of Al2O3/HfO2/Al2O3 has been proposed. The trilayer structure device units of Al2O3/HfO2/Al2O3 on TiN-coated Si prepared by ALD may be a potential candidate for oxide-based resistive random access memory.

Keywords: Atomic layer deposition; Non-volatile memory; Resistance random access memory; Trilayer structure.