High Total-Dose Proton Radiation Tolerance in TiN/HfO 2 /TiN ReRAM Devices
- PDF / 278,625 Bytes
- 6 Pages / 432 x 648 pts Page_size
- 77 Downloads / 235 Views
High Total-Dose Proton Radiation Tolerance in TiN/HfO2/TiN ReRAM Devices Xiaoli He1and Robert E. Geer1 1 College of Nanoscale Science and Engineering, University at Albany, State University of New York, Albany, NY 12203 ABSTRACT The resistive switching properties of CMOS compatible TiN/HfO2/TiN resistive-randomaccess-memory (ReRAM) devices have been investigated after exposure to 1 MeV proton radiation. The HfO2-based ReRAM devices were found to have high total-ionizing-dose (TID) radiation tolerance up to 5 Grad(Si). TiN/HfO2/TiN ReRAM performance parameters include high-resistance state (HRS) resistance, low-resistance state (LRS) resistance, set and reset voltages. HfO2-based ReRAM devices exhibited no degradation in these performance parameters following proton irradiation exposure with TID from 105 to 109 rad(Si). Furthermore, the HfO2-based ReRAM devices exhibited more uniform resistive switching behavior with increased TID. Based on this radiation response it is proposed that the resistive switching mechanism in TiN/HfO2/TiN – trap-assisted tunneling associated with Hf-rich conducting filament formation – may be reinforced through proton exposure which acts to stabilize the formation/rupture of Hf-rich filaments. The high radiation tolerance of HfO2-based ReRAM devices suggests such devices may be potentially attractive for aerospace and nuclear applications. INTRODUCTION Metal oxide-based resistive random access memory (ReRAM) devices have attracted attention recently for potential application in nonvolatile memory (NVM) systems due to their simple structure (metal-insulator-metal), CMOS compatibility, high storage density and low power consumption [1, 2]. Among the numerous transition metal oxide materials that exhibit resistive switching behavior, HfO2-based ReRAMs have been extensively studied and have shown excellent performance with low operation voltages (< 1V), high endurance (> 106 cycles), fast switching speed (< 100 ns), and reliable data retention (extrapolated 10 years) [3-6]. Various resistive switching mechanisms for ReRAMs have been proposed. Arguably, the consensus switching mechanism consists of the formation and rupture of conducting filaments with high oxygen vacancy concentrations (i.e. locally metallic) [5, 6]. This applies to the switching mechanism for TiN/HfO2/TiN ReRAM devices, wherein trap-assisted tunneling (TAT) leads to the reversible formation of Hf-rich conducting filaments [5, 6]. As NVM systems are also widely used in the aerospace and nuclear industries, there is a need to study the effects of radiation on these ReRAM devices. Previous radiation study on HfO2-based ReRAMs found that Pt/HfO2:Cu/Cu devices are radiation-immune to a TID of 350 krad(Si) Co-60 radiation [7] and 5 Grad(Si) protons but with degradation in set/reset voltages and on/off resistance [8]. A comparison of radiation response between Pt/HfO2:Cu/Cu and TiN/HfO2/TiN devices were also conducted by our group under 3 different TIDs: 1.5, 3, and 5 Grad(Si), showing that TiN/HfO2/TiN ReRAM devices have superior r
Data Loading...
