Presentation Information
[15a-PB1-9]Coexisting Ferroelectric and Resistive Switching HfZrO2 Capacitors toward High-Density Integrated Memory Architecture
〇(D)KuanLin Chen1, Junkai Lai1, WenRuey Yang1, Karthekeyan Periasamy2,3, JerChyi Wang1,4,5 (1.Chang Gung Univ., 2.Aalto Univ., 3.Nokia Networks & Solutions Oy, 4.Chang Gung Memorial Hospital, 5.Ming Chi Univ. of Tech.)
Keywords:
Memory,Ferroelectric,ReRAM
Hafnium zirconium dioxide (HfZrO2, HZO) has emerged as a CMOS-compatible ferroelectric material and has also been reported to exhibit resistive switching behavior under specific bias conditions. With an increasing demand in high bandwidth memory (HBM), the understanding of the coexistence and transition between these two memory characteristics is essential for reliable device operations. In this work, the memory behavioral transition from ferroelectricity to resistive switching in TiN/HZO/Pt capacitors with a 10-nm-thick HZO thin film fabricated by plasma-enhanced atomic layer deposition (PEALD) was investigated. In the pristine state, the HZO capacitors exhibited well-defined polarization–electric field (P–E) hysteresis loops with clear polarization switching and stable endurance, confirming the robust ferroelectric properties. Upon the resistive switching operation, stable high-resistance and low-resistance states were achieved for more than 140 resistive switching cycles, as shown in Fig. 1(a). However, a gradual degradation in ferroelectric behavior of the HZO capacitors was observed when the number of resistive switching cycles increased, as shown in Fig. 1(b). The electrical characterization revealed a significant reduction in polarization of HZO thin films, accompanied by the shrinkage and eventual disappearance of the P–E hysteresis loops after repeated resistive switching operation. As schematically illustrated in Fig. 1(c), this degradation was attributed to the accumulation of oxygen vacancies to form a conductive filament within the HZO layer, distorting the internal electric field and increase the leakage current. These results demonstrate that the ferroelectric and resistive switching behaviors can coexist and dynamically transition within a HZO capacitor, governed by defect evolution during electrical operation.