Light‐Mediated Multi‐Level Flexible Copper Iodide Resistive Random Access Memory for Forming‐Free, Ultra‐Low Power Data Storage Application

Abstract

This study demonstrates the efficacy of an emerging p-type copper iodide (CuI) semiconductor in a flexible, low-voltage resistive random-access memory (RRAM), which can be readily integrated with metal-oxide n-type counterparts for complementary circuit systems. Herein, CuI RRAM devices are implemented via a room-temperature solid iodination process, exhibiting a consistent On/Off ratio (≈10 4 ), excellent endurance of more than ≈10 3 cycles, together with a long retention period (> 5 × 10 4 s). Furthermore, a scheme of light-mediated multi-level data storage is demonstrated using blue light illumination (λ = 455 nm), to exploit possible photonic memristive functionality through notable photo-response of CuI. In addition, the current conduction and resistive switching behaviors are systematically studied via low-temperature measurements from 203 to 343 K, validating thermal stability and the governing key switching mechanism in CuI RRAM devices. The longstanding problem with CuI device longevity is effectively addressed via PMMA encapsulation, resulting in a 15-fold improvement in the lifespan of devices even in air, as compared with non-passivated devices. These findings suggest that flexible optoelectronic systems, combined with reliable, ultra-low power CuI RRAM devices with photo memristive functionality, can leverage the enhancement of multifunctional selectors required in process-in-memories and the synaptic elements of neuromorphic applications.

Photoelectric Multilevel Memory Device based on Covalent Organic Polymer Film with Keto–Enol Tautomerism for Harsh Environments Applications

“…The results revealed that the ON/OFF ratios of Py-COP-0 and Py-COP-3 were 1.73 × 10 5 and 5.06 × 10 5 , respectively, which suggests that these devices meet the requirements of memristor device applications and can be applied to big data storage. [32] The first SET voltage (V th1 ) of the Py-COP-3-based device was distributed in the range of 0.91-1.34 V, while the second SET voltage (V th2 ) was mainly centralized between 1.69 and 1.89 V (Figure 2e). Compared to the broad V th1 distribution of Py-COP-0, Py-COP-3-based devices were more consistent with V th , suggesting the possibility for the Py-COP-3-based devices to be a candidate for multilevel resistive memory.…”

A Dual‐Functional Perovskite‐Based Photodetector and Memristor for Visual Memory

“…Moreover, the conduction in the HRS can be divided into two segments (Figures S12 and S13, Supporting Information): Ohmic contact (I ∝ V) and Schottky contact (log(I) ∝ V 1/2 ). [30][31][32][33] Initially, the migration of diffused cations (mainly Ag + ) from the Au/Ag is governed by the conduction mechanism of thermionic Schottky emission: lnI ∝ √ q 3 4𝜀𝜋d kT × √ V (I is the current, 𝜖 is the dielectric constant, q is the electrical charge, d is the thickness of the Cs 3 Sb 2 I 9 microplate, and V is the applied voltage). The observed transition from the Schottky behavior to Ohmic behavior indicates that the unfilled trap centers are gradually seized by the charged carriers; therefore, the Schottky barrier is overcome by ion migration and arrangement, leading to a larger current increment with the increased voltage.…”

Back-End-of-Line Compatible Large-Area Molybdenum Disulfide Grown on Flexible Substrate: Enabling High-Performance Low-Power Memristor Applications

“…At higher I cc , a higher V reset is needed, due to the stronger filament formation compared to the lower I cc . 33 Therefore, at lower I cc , V reset tends to zero, indicating the formation of a weak conducting filament, which required a lower V for dissolution. The multilevel RS memristors are also attractive for low-power electronic applications.…”

“…V set shows an insignificant change; however, V reset decreases with decreasing I cc . At higher I cc , a higher V reset is needed, due to the stronger filament formation compared to the lower I cc . Therefore, at lower I cc , V reset tends to zero, indicating the formation of a weak conducting filament, which required a lower V for dissolution.…”