Radiation Response of HfO_x-Based Resistive Random Access Memory (RRAM) Devices

Abstract

A report on the fabrication and radiation response of HfO x thin film-based resistive random access memory (RRAM) devices is presented in this study. Au/HfO x /Au cross-bar (10 μm × 10 μm) structures were used to study the effects of ion irradiation on their switching properties. One hundred twenty megaelectron volt (120 MeV) Ag 7+ ions with fluence values ranging from 5E10 to 5E12 ions/cm 2 were employed in this work. The resistance (high to low) ratio was found to increase until a critical fluence of 5E11 ions/cm 2 was reached, and it decreased beyond this fluence. Furthermore, it is observed that the singly charged positive oxygen-vacancy defects (V O + ) are more dominant and have a major contribution in the switching cycles for these RRAM devices. The observed trends in the electrical properties of these devices are correlated with the changes in the densities of charged defects relative to neutral defects in the switching medium. Possibilities of employing these RRAM devices as radiation detectors are also discussed.

Uniformity Improvement of Ti/ZrO2/Pt RRAM by Analyzing and Reducing Current Overshoot

“…The transition from a high-resistance state to a low-resistance state in this device is predominantly driven by the formation of conductive filaments through oxygen vacancies, making the oxygen vacancy concentration closely related to the device resistance change. − Therefore, the I – V characteristics obtained from the tests conducted at different temperatures can reflect the variations in the oxygen vacancy concentration. During the testing, the same limiting current was applied to control the growth of conductive filaments, the resulting I – V characteristics at different temperatures as shown in Figure a.…”

Optimization of the Forming Process of HfOx-Based RRAM to Achieve Bidirectional Forming and Enhanced Switching Performance by Inserting an Oxygen-Vacancy-Rich Layer

“…In the past few decades, with the explosive growth of data, manufacturers have had greater demand for making smaller, higher-performance chips in fields such as artificial intelligence and big data. Because of its low operating voltage, high packaging density, fast switching speed, and low power consumption, resistive random access memory (RRAM) has become a formidable contender for the upcoming generation of nonvolatile memory and neuromorphic devices. − The structure of the RRAM is usually a metal–insulator–metal multilayer structure. At present, the conductive filament (CF) theory is widely accepted for the switching mechanism, which describes the transformation between the low resistance state (LRS) and high resistance state (HRS) by controlling the formation and rupture of CFs under external pulses. − …”

Coexistence of Interfacial and Filamentary Resistance Switching in Ti/SiO x /Au Resistive Memory Devices

“…Several recent works have successfully demonstrated the feasibility of energyefficient, in-memory computing [3] frameworks with high-density RRAM crossbar arrays [4], . Most RRAM artificial synapses employ a Valence Change Memory (VCM) cell with a high-k metal oxide such as HfOx [5] or TiOx [6] as the active switching material. The resistance switching operation in such devices is governed by an oxygen-vacancy driven filament formation/rupture process [7].…”