Transparent and Flexible Copper Iodide Resistive Memories Processed with a Dissolution-Recrystallization Solution Technique

Abstract

This study explores a class of resistive memory candidatessimple binary halidesand demonstrates their efficacy in switching between high- and low-resistive states. Herein, copper halide, particularly copper iodide (CuI), is investigated for its resistive switching efficacy when sandwiched between indium tin oxide (ITO) and silver electrodes on flexible polyethylene terephthalate (PET) substrates. CuI is deposited on ITO-coated PET using an innovative dissolution-recrystallization technique, in which a deposition temperature of 80 °C is sufficient to eliminate the carrier solventacetonitrileand impart considerable densification of CuI for effective memory characteristics. The PET/ITO/CuI is transparent (>90%), and the PET//ITO/CuI/Ag devices display states of notably low- and high-resistive states with a ratio of more than 10 within a voltage biasing range of −2.5 to +2.5 V. Additionally, the devices exhibit similar resistive states under bending stress. Halides (in particular, CuI) are, thus, introduced as a class of active materials for transparent and flexible resistive memories.

In Situ Synthesis of Two-Dimensional Lateral Semiconducting-Mo:Se//Metallic-Mo Junctions Using Controlled Diffusion of Se for High-Performance Large-Scaled Memristor

“…37,38 To further elucidate the switching mechanism, the I−V curve during the SET process was analyzed with a double logarithmic plot, as shown in Figure S14 (Supporting Information), where the slope of the I−V curves indicates that the charge migration is consistent with the trap-controlled space charge limited conduction (SCLC) model. 8 At the beginning of the HRS, I ∝ V 1.1 , suggesting ohmic conduction. With increasing voltage, the slope of the I− V curve changes to ∼2 (I ∝ V 2 ; Child's law), followed by ∼5 (I ∝ V 5 ), indicating a rapid transition from trap-unfilled to trapfilled SCLC.…”

“…To meet the increasing demand for large data processing and storage, developing alternate computing hardware for beyond-complementary-metal-oxide-semiconductor electronics is essential . The next-generation storage devices are crossbar arrays of memory cells known for their high density, rapid operation, and multilevel conductance during low-power operation. − The performance of memristors utilizing transition-metal oxides and organic molecules has advanced tremendously; however, they fail to meet energy efficiency requirements, easy fabrication, and computational tasks. − In contrast, memristors based on two-dimensional (2D) materials exhibit excellent performance owing to their controllable van der Waals gaps, defect-free surfaces, exceptional thermal and mechanical stability, and promising resistive switching (RS) behavior with a high RS ratio and low switching voltage. − Several studies have been conducted employing 2D layered materials such as MoS 2 , HfSe 2 , etc. to fabricate crossbar memristors via mechanical exfoliation, which limits the thickness uniformity over a large area, resulting in locally limited performance or variable performance characteristics. , Therefore, considerable efforts have been made to fabricate large-area crossbar memristor arrays by liquid-phase exfoliation and spin coating; however, limitations in area scaling and uncontrollable morphology lead to poor endurance and device density. , …”

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

“…A variety of CuI synthesis methods have been employed for electronic applications, including the use of reactive sputtering, [24] spin coating of CuI solution, [25] dip coating, [26] thermal evaporation of CuI, [27] and others. [28][29][30] Surprisingly, a CuI NVM has rarely been reported, [22,23] and further in-depth studies, including long-term endurance, charge transport mechanisms, and others, are limited, possibly due to the poor stability of the film. This low stability is caused by mediocre CuI film surface and morphology, which depends on the synthesis route.…”

“…Surprisingly, a CuI NVM has rarely been reported, [ 22,23 ] and further in‐depth studies, including long‐term endurance, charge transport mechanisms, and others, are limited, possibly due to the poor stability of the film. This low stability is caused by mediocre CuI film surface and morphology, which depends on the synthesis route.…”

“…[21] On the other hand, there are barely any reports on the stable operation of CuI resistive random access memory (RRAM) with a multivalued scheme, or the in-depth study of switching mechanisms, which could lead to the aforementioned core electronic applications. [22,23] As one of the possible reasons, even after considerable efforts, no ideal deposition method for the NVM application has been established to control CuI film texture and curtail defect densities. Accordingly, a thorough…”