Light‐Tunable Nonvolatile Memory Characteristics in Photochromic RRAM

Abstract

Light‐tunable resistive switching (RS) characteristics are demonstrated in a photochromophore (BMThCE)‐based resistive random access memory. Triggered by nondestructive ultraviolet or visible light irradiation, two memory‐type RS characteristics can be reversibly modulated in the same device upon a narrow range of applied voltage (<6 V), accompanied by the photochromophores in the active layer reversibly changed between ring‐open state (namely, o‐BMThCE) and ring‐closed state (namely, c‐BMThCE). The o‐BMThCE‐based memory exhibits a write‐once‐read‐many characteristic with a high current on/off ratio of 105, while the c‐BMThCE‐based one shows a flash characteristic. Both of the RS characteristics present good nonvolatile stability with the resistance states maintained over 104 s without variation. This RS modulation is possibly related to the formation and rupture of conductive filaments, which formed along channels consisting of BMThCE trapping molecules. This work provides a new memory element for the design of light‐controllable high density storage and data encryption technology.

Photocatalytic Reduction of Graphene Oxide–TiO2 Nanocomposites for Improving Resistive‐Switching Memory Behaviors

“…The switching time is sensitive to the test temperature. As shown in Figure d,g, the SET switching time t decreased exponentially with rising temperature, which follows the Arrhenius relationwhere E a , k B , and T are the barrier energy, Boltzmann constant, and temperature, respectively. As shown in Figure e,h, the barrier energy can be extracted from the slope of the Arrhenius plots.…”

Functional Non‐Volatile Memory Devices: From Fundamentals to Photo‐Tunable Properties

“…On this account, organic photochromic molecules drew considerable attentions in the application of varieties of light tunable memory . Especially, among the organic small molecules, diarylethenes (DAEs) are very popular members among a range of photochromic molecules owning the advantages of outstanding thermal stability as well as efficient and robust photoisomerization process (i.e., fatigue resistant) …”

“…Recently, Ling et al demonstrated a photochromic ReRAM with BMThCE, which belongs to a DAE derivative, as the functional layer exhibiting reversible transformation between WORM and non‐volatile bipolar resistive switching characteristics (Figure ). Also, the two reversible memory‐type characteristics were proved at low external voltages sweeping, resulting from invertible photochromism between o ‐BMThCE (ring open state) and c ‐BMThCE (ring closed state).…”

“…d) Energy band of memory based on two isomers. Reproduced with permission . Copyright 2017, Wiley‐VCH.…”

Controlled Nonvolatile Transition in Polyoxometalates‐Graphene Oxide Hybrid Memristive Devices

“…Hung et al observed an irreversible switching from high resistance to WORM‐ and bipolar‐ type memory by changing the UV irradiation parameters . Recently, by incorparating of photochromophore (BMThCE) material in RRAM device, Huang et al demonstrated a reversible switching between WORM and bipolar memory characteristic through switching over the visible light and UV irradiation due to the modulation of trap depth …”