Excellent Memory Characteristics Research Articles

Doping- and capacitor-less 1T-DRAM cell using reconfigurable feedback mechanism

In this paper, we propose a doping- and capacitor-less 1T-DRAM cell, which achieved virtual doping by leveraging charge plasma and bias-induced electrostatic doping (bias-ED) techniques in a 5 nm-thick intrinsic silicon body, thereby eliminating doping processes. Platinum was in contact with the drain, while aluminum was in contact with the source, enabling virtual doping of the silicon body into ap*-i-n* configuration via the charge-plasma technique. Two coupled polarity gates and one control gate are positioned above the intrinsic channel region. The intrinsic channel region is virtually doped through the bias-ED by applying voltages to the gates, forming potential wells inside the channel. The voltage applied to the two coupled polarity gates determines whether the device operates in thep- orn-channel mode, whereas the control gate governs the flow of charge carriers. Charge carriers are stored and released in the potential wells inside the channel by adjusting the gate, effectively replacing the capacitor. In this device, the placement of polarity gates on either side of the control gate enables the observation of the reconfigurable characteristics. Moreover, the proposed device utilizes a feedback mechanism, enabling excellent memory characteristics such as a high on/off current ratio of ∼109, steep switching behavior of ∼0.2µV dec-1, short write time of 10 ns, long hold retention of over 100 s, and long read retention of over 600 s.

Hofmeister effect driven dynamic-bond cross-linked dialdehyde xylan hydrogels with rapid response and robust mechanical properties for expanding stent

The biomedical field urgently needs for programmable stent materials with nontoxic, autonomous self-healing, injectability, and suitable mechanical strength, especially self-expanding characteristics. However, such materials are still lacking. Herein, based on gelatin and dialdehyde-functionalized xylan, we synthesized 3D-printable, autonomous, self-healing, and mechanically robust hydrogels with a reversible Schiff base crosslink network. The hydrogels exhibited excellent mechanical properties and automatic healing properties at room temperature. The solid mechanical properties originate from the Schiff base, hydrogen bonding interactions, and xylan nanoparticle reinforcement of the polymer networks. As a proof of concept, the Hofmeister effect enabled the hydrogel to contract in highly concentrated salt solutions. In contrast, the same hydrogel expanded and relaxed in dilute salt solutions (quick response within 10 s), showing ionic stimulus-response and excellent shape memory characteristics, which demonstrated that the prepared hydrogel could be used as self-expanding artificial vascular stents. In particular, good biocompatibility was confirmed by cytotoxicity and compatibility tests, and ex vivo arterial experiments further indicated the feasibility of these artificial vascular scaffolds (the expansion force reached 1.51 N). Combined with its ionic stimuli-responsive shape memory ability, the strong mechanical, self-healing, 3D-printable, and biocompatibility properties make this hydrogel a promising material for artificial stents in various biomedical applications.

Terminalia bellirica (Gaertn.) Roxb. extract-mediated green synthesis of magnesium oxide nanoparticles for multifunctional applications

Green synthesis has emerged as a pivotal facet of nanotechnology, garnering significant attention for its inherent safety and eco-friendly attributes. This study presents a novel approach utilizing phytochemicals derived from Terminalia bellirica (Gaertn.) Roxb. fruit extract for the environmentally benign synthesis of magnesium oxide (MgO) nanoparticles. The resultant MgO nanoparticles were comprehensively characterized using UV–visible spectroscopy, X-ray Diffractometer (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Energy dispersive X-ray (EDX), and High-Resolution-Transmission Electron Microscope (HR-TEM). The synthesized MgO nanoparticles exhibited remarkable stability, evidenced by zeta potential of −8.84 mV and an average size of 73.41 nm. In an eco-physiological context, the application of MgO nanoparticles at a concentration of 5 mg/100 ml significantly enhanced shoot length (7.94±0.70 cm), root length (8.44±0.53 cm), moisture content (97.16±0.83%), and chlorophyll expression (18.34±0.99 mg/g fresh weight (FW)) in Trigonella foenum-graecum seedlings. Furthermore, the MgO nanoparticles demonstrated biocompatibility with soil bacteria and exhibited potent photocatalytic activity, achieving a 42% degradation efficiency of the organic dye methyl orange under UV irradiation for 60 minutes. In the realm of biomedical applications, MgO nanoparticles displayed dose-dependent cytotoxicity against human breast cancer cells (MCF-7), with an IC50 value of 37.39±0.05 µg/ml. Remarkably, MgO nanoparticles were also harnessed for their memcapacitive properties, showcasing excellent non-volatile memory characteristics, including endurance for 15,000 cycles and retention for 4000 seconds. In summary, this study underscores the multifunctional prowess of MgO nanoparticles synthesized through Terminalia bellirica fruit extract, spanning applications in plant physiology, environmental remediation, cancer therapeutics, and nanoelectronics. The environmentally conscious synthesis approach and diverse functionalities presented herein position these nanoparticles as future promising candidates for sustainable and versatile technological advancements.

Superlow Power Consumption Memristor Based on Borphyrin-Deoxyribonucleic Acid Composite Films as Artificial Synapse for Neuromorphic Computing.

Memristor synapses based on green and pollution-free organic materials are expected to facilitate biorealistic neuromorphic computing and to be an important step toward the next generation of green electronics. Metalloporphyrin is an organic compound that widely exists in nature with good biocompatibility and stable chemical properties, and has already been used to fabricate memristors. However, the application of metalloporphyrin-based memristors as synaptic devices still faces challenges, such as realizing a high switching ratio, low power consumption, and bidirectional conductance modulation. We developed a memristor that improves the resistive switching (RS) characteristics of Zn(II)meso-tetra(4-carboxyphenyl) porphine (ZnTCPP) by combining it with deoxyribonucleic acid (DNA) in a composite film. The as-fabricated ZnTCPP-DNA-based device showed excellent RS memory characteristics with a sufficiently high switching ratio of up to ∼104, super low power consumption of ∼39.56 nW, good cycling stability, and data retention capability. Moreover, bidirectional conductance modulation of the ZnTCPP-DNA-based device can be controlled by modulating the amplitudes, durations, and intervals of positive and negative pulses. The ZnTCPP-DNA-based device was used to successfully simulate a series of synaptic functions including long-term potentiation, long-term depression, spike time-dependent plasticity, paired-pulse facilitation, excitatory postsynaptic current, and human learning behavior, which demonstrates its potential applicability to neuromorphic devices. A two-layer artificial neural network was used to demonstrate the digit recognition ability of the ZnTCPP-DNA-based device, which reached 97.22% after 100 training iterations. These results create a new avenue for the research and development of green electronics and have major implications for green low-power neuromorphic computing in the future.

Implementation of Photosynaptic and Electrical Memory Functions in Organic Nano‐Floating‐Gate Transistors via a Perovskite‐Nanocrystal‐Based Nanocomposite Tunneling Layer

An organic nano‐floating‐gate transistor (ONFGT) with both photosynaptic and electrical memory functions is developed using a perovskite (CsPbBr3) NC‐insulating polymer (polystyrene; PS) nanocomposite and CsPbBr3 NCs as the tunneling and floating gate layers, respectively. The introduction of the CsPbBr3 NCs–PS nanocomposite layer improves the photoresponsivity of the ONFGT under ultraviolet–visible irradiation, resulting in an increase in both the photocurrent and the light‐to‐dark current ratio by 10−8 A and 104 orders of magnitude, respectively. It also exhibits high responsivity (0.804 A W−1) and external quantum efficiency (249.3%) under 400 nm irradiation. Furthermore, the photosynaptic characteristics of the ONFGT under visible‐light irradiation are investigated. To mimic biological nervous systems, the photocurrent of the device is dynamically modulated by varying the light intensity and duration. Notably, an increase in synaptic weight is observed under repeated photonic stimulations, as shown by changes in synaptic weight with each light pulse. Also, the ONFGT exhibits excellent nonvolatile memory characteristics in the dark, displaying a hysteresis window value of 2.9 V for a gate double sweep under ±5.0 V. Consequently, the perovskite NCs–insulating polymer nanocomposite tunneling layer is crucial for enabling photoresponsivity and memory characteristics in nano‐floating‐gate transistors, making them suitable for multifunctional electronic devices.

Near-Infrared Light Responsive Surface with Switchable Wettability in Microstructure and Surface Chemistry

Intelligent surfaces with reversibly switchable wettability have recently drawn considerable attention. One typical strategy to obtain such a surface is to change the surface chemistry or the microstructure. Herein, we report a new smart surface for which the wettability was controlled by both the surface chemistry and microstructure. Various wetting states were reversibly and precisely controlled through heating, pressing, NIR irradiation, and oxygen plasma treatment. The excellent shape memory characteristics of shape memory polyurethane (SMPU) and the controlled release of hydrophobic/hydrophilic oxygen-containing functional groups contributed to this ability. Microcapsules were used to design these smart surfaces. They controlled the release of a fluorinated alkyl silane (FAS) through shell melting, changed the surface composition, and played a decisive role in protecting the FAS against hydrolysis and evaporation to ensure that the surface's wettability is recyclable. Controlling of the surface chemistry or microstructure was repeated for at least 19 or 16 cycles, respectively, which indicated excellent repeatability compared to other smart surfaces. Based on the excellent controllability, the surface exhibited multiple functions, such as liquid directional transport and coefficient of friction control. In addition, it maintained this extraordinary ability under harsh environments owing to the great stability of the SMPU and adequate protection of the FAS by the microcapsules. With switchable wettability based on the surface chemistry and microstructure, this work provides a new principle for designing smart surfaces with wettability controlled in two ways.

The Doping Effect on the Intrinsic Ferroelectricity in Hafnium Oxide-Based Nano-Ferroelectric Devices.

Hafnium oxide (HfO2)-based ferroelectric tunnel junctions (FTJs) have been extensively evaluated for high-speed and low-power memory applications. Herein, we investigated the influence of Al content in HfAlO thin films on the ferroelectric characteristics of HfAlO-based FTJs. Among HfAlO devices with different Hf/Al ratios (20:1, 34:1, and 50:1), the HfAlO device with Hf/Al ratio of 34:1 exhibited the highest remanent polarization and excellent memory characteristics and, thereby, the best ferroelectricity among the investigated devices. Furthermore, first-principal analyses verified that HfAlO thin films with Hf/Al ratio of 34:1 promoted the formation of the orthorhombic phase against the paraelectric phase as well as alumina impurities and, thus, enhanced the ferroelectricity of the device, providing theoretical support for supporting experimental results. The findings of this study provide insights for developing HfAlO-based FTJs for next-generation in-memory computing applications.

Thermal responsive photopolymerization 3D printed shape memory polymers enhanced by heat transfer media

AbstractPhotosensitive resins are the research and development foundation of photopolymerization 3D printed products. We have found that cyclic trimethylolpropane formal acrylate (CTFA) and 2‐phenoxy ethyl acrylate (PHEA) resins are suitable for UV‐curable 3D printing consumables. Their photopolymers exhibit excellent shape memory characteristics at shape change temperature, shape recovery speed, shape extension limit, and shape maintenance ability. Moreover, we have analyzed the internal and external factors affecting these shape memory characteristics through several tests, including multi‐scale structure observation, thermal analysis, and mechanical tests. Furthermore, the complex hollow model design and multiple heat transfer media are adopted to expand the concept of additive manufacturing, and improve the practicability of 4D printing intelligent products.

New ternary inverter with memory function using silicon feedback field-effect transistors

In this study, we present a fully complementary metal–oxide–semiconductor-compatible ternary inverter with a memory function using silicon feedback field-effect transistors (FBFETs). FBFETs operate with a positive feedback loop by carrier accumulation in their channels, which allows to achieve excellent memory characteristics with extremely low subthreshold swings. This hybrid operation of the switching and memory functions enables FBFETs to implement memory operation in a conventional CMOS logic scheme. The inverter comprising p- and n-channel FBFETs in series can be in ternary logic states and retain these states during the hold operation owing to the switching and memory functions of FBFETs. It exhibits a high voltage gain of approximately 73 V/V, logic holding time of 150 s, and reliable endurance of approximately 105. This ternary inverter with memory function demonstrates possibilities for a new computing paradigm in multivalued logic applications.

Transparent Organic Nonvolatile Memory and Volatile Synaptic Transistors Based on Floating Gate Structure

In order to comply with the rapid development of new-generation electronics, developing memories which could meet the demands for specific application such as flexibility, transparency and neuromorphic functions are of great significance. In this work, a transparent organic nonvolatile memory (transparency≥81%) is developed with Ag nanowire as floating gate layer, which exhibits excellent memory characteristics and mechanical flexibility. Moreover, the transition from memory to artificial synapse is achieved by adjusting the concentration of Ag nanowire. This work provides a new solution for transparent flexible memory and shows their potential for next-generation transparent organic electronics.

Shape memory elastomers: A review of synthesis, design, advanced manufacturing, and emerging applications

AbstractShape memory elastomers (SMEs) are a class of intelligent materials characterized by their ability to deform and recover shapes under applied force and external stimuli. Heat and ultraviolet radiation are examples of the most common external stimuli. With the emerging prevalence of internet of things devices and the ensuing need for smart materials and structures, SMEs provide significant opportunities to support the development of novel applications in robotics, remotely actuated systems, and packages, including those promised for the space industry. To harness the immense potential in the emerging applications of these materials, one approach is the systematic multi‐scale modeling coupled with artificial intelligence‐assisted design leading to the development of next‐generation intelligent systems. This review covers several aspects of the synthesis/materials chemistry and applications of SMEs with a view towards enabling such an approach. The synthesis procedures emphasizing dynamic covalent bond reactions are reviewed. Then, liquid crystalline elastomers are introduced as a specific elastomeric material class that exhibits excellent shape memory characteristics and distinctive transition temperatures. The utilization of advanced manufacturing methods such as additive manufacturing, three‐dimensional printing, and the emerging four‐dimensional printing technologies assisted by machine learning are detailed in producing and predicting SMEs. Finally, the current trends in the use of SMEs are summarized in areas of industrial and space engineering and biomedical applications.

Effect of the Oxygen Composition Control of HfOx Films on Threshold and Memory Switching Characteristics for Hybrid Memory Applications

AbstractConsidering a high‐density vertical X‐point memory array, the film thickness of an active device for the selector and memory needs to be scaled down. Here, the authors propose an AgTe/HfOx‐based hybrid memory device with a film thickness of less than 10 nm by adopting a bilayer (HfO1.8/HfO2) film using precise composition control. Non‐volatile switching characteristics can be obtained by considering the formation of stable nanoscale Ag filaments in the nanoporous region in non‐stoichiometric HfO1.8 deposited via sputtering. By contrast, volatile switching characteristics are achieved by an unstable atomic‐scale Ag path in stoichiometric HfO2 deposited via plasma‐enhanced atomic layer deposition. Based on density functional theory calculations, it is confirmed that the stoichiometry of the HfOx film is the key parameter that controls the switching characteristics. The bilayer (HfO1.8/HfO2) device exhibits excellent hybrid memory characteristics, such as distinct read margin (>1.5 V), high ON/OFF ratio (>106), and extremely low OFF current (≈pA), for vertical X‐point memory applications.

Reservoir Computing on Atomic Switch Arrays with High Precision and Excellent Memory Characteristics

Reservoir Computing on Atomic Switch Arrays with High Precision and Excellent Memory Characteristics

Electrolyte Incorporation in Anodic Memristors

In the field of semiconductor electronics, the metal-oxide- semiconductor technology (CMOS) has attracted a lot of scientific attention as one of the main representatives for non-volatile memories. The development of memory systems is crucial for a fast data processing for which purpose namely microprocessors are used, following the miniaturization trends at the same time. However, the limits of CMOS technology are already exhausted in terms of power consumptions, leakage current and processing speed. Surely, novel non-volatile elements and materials are necessary to fulfill such demands and memristors are in the front as the most promising candidates.Valve metals and their oxides are frequently used as the main constitutes of metal-insulator-metal (MIM) memristive structures. Recently, Hf and Ta became the most studied valve metals playing an important role in the next-generation of thin film micro- and nano-electronic devices primarily due to applications in redox-based resistive switching memories (ReRAMs), logic circuits, sensors and artificial neural networks. The operating mechanism of memristors is based on the electric field assisted conductive filaments (CFs) formation due to the ionic drift inside the insulating oxide layer. The understanding of CFs formation is a key point to ensure excellent switching and memory characteristics of memristive devices. In accordance with the reported studies, the regulated movement of oxygen vacancies or other mobile species through the CFs can allow their pining at the constant positions and consequently high switching reproducibility of a device. Therefore, the immediate findings on the oxygen enriched media that will ensure the controlled CFs formation is of high importance. With this regard, the selection of a proper electrolyte for the fabrication of the oxide layer sandwiched between two metallic electrodes may play a significant role. It can be assumed that incorporation of electrolyte species can increase the amount of oxygen vacancies leading to a possible manipulation with their movement.Tantalum and Hf were sputtered onto Si wafers to produce thin films. Both metals were electrochemically anodized to produce oxides responsible for the memristive properties. The aim was to replace expensive fabrication methods for oxides such as sputtering or laser deposition with cost-efficient, simple and rapid anodization. The bottom electrode was either Ta or Hf thin films, Ta2O5 or HfO2 were anodic oxide layers and Pt was patterned as the top electrode, that can be seen in the inserted Figure. Two groups of these samples were anodized in the same conditions, in three electrolytes (phosphate buffer (PB), borate buffer (BB), citrate buffer (CB)) to produce three different anodic oxide layers with the thickness in the range of 20 nm. For all cases, memristive switching between high and low resistance states was demonstrated and the corresponding I-U switching curves were compared. Additionally, writing (switching) and reading tests were done for high numbers of cycles and the endurance and retention of devices were analyzed. The same tests were performed when samples were thermally treated resulting in improved or worsened switching properties, depending on the solid electrolyte placed between the metallic electrodes. Unquestionably, the use of PB, CB and BB for anodization has differently influenced the electrical properties of the memristors likely due to the trapped electrolyte species inside the oxide layer. The incorporation was confirmed by the X-ray photoelectron spectroscopy (XPS) and the presence of CFs by transmission electron microscopy (TEM). Interestingly, Ta memristors formed in PB showed the presence of Ta oxyphosphate which has induced the increase of O vacancies and thus improved switching features. However, the presence of Hf-O-P bonds found in Hf memristors that was anodized in PB did not show any improvement of electrical properties.In summary, the current study offers a reliable, controllable and cost-efficient approach for the production of ReRAMs based on Hf and Ta anodic memristors as potential candidates for the future industrial implementation. Figure 1

Toward Highly Robust Nonvolatile Multilevel Memory by Fine Tuning of the Nanostructural Crystalline Solid-State Order.

Organic resistive memory (ORM) offers great promise for next-generation high-density multilevel-cell (MLC) data storage. However, the fine tuning of crystalline order among its active layer still remains challenging, which largely restricts ORM behavior. Here, an exceptional solid-state transition from disordered orientations to highly-uniform orientation within the ORM layer is facilely triggered via molecular strategic tailoring. Two diketopyrrolopyrrole-based small molecular analogues (NI1 TDPP and NI2 TDPP) are demonstrated to display different symmetry. The asymmetric NI1 TDPP shows an irregular solid-state texture, while the centro-symmetric NI2 TDPP conforms to an ordered out-of-plane single-crystalline pattern that aligns with the foremost charge transportation along the substrate normal, and exhibits excellent MLC memory characteristics. Moreover, this highly oriented pattern guarantees the large-area film uniformity, leading to the twofold increase in the yield of as-fabricated ORM devices. This study reveals that the solid-state crystalline nanostructural order of organic materials can be controlled by reasonable molecular design to actuate high-performance organic electronic circuits.

Polarization‐Resolved Broadband MoS2/Black Phosphorus/MoS2 Optoelectronic Memory with Ultralong Retention Time and Ultrahigh Switching Ratio

AbstractThe rapidly emerging requirement for device miniaturization and structural flexibility make 2D semiconductors and their van der Waals (vdWs) heterostructures extremely attractive for nonvolatile optoelectronic memory (NOM) applications. Although several concepts for 2D NOM have been demonstrated, multi‐heterojunction devices capable of further improving storage performance have received little attention. This work reports a concept for MoS2/black phosphorus (BP)/MoS2 multi‐heterojunction NOM with artificial trap sites through the BP oxidation, in which the trapped holes at BP/POx interface intrigue a persistent photoconductivity that hardly recovers within the experimental time scales (exceeding 104 s). As a result of the interfacial trap‐controlled charge injection, the device exhibits excellent photoresponsive memory characteristics, including a record high detectivity of ≈1.2 × 1016 Jones, a large light‐to‐dark switching ratio of ≈1.5 × 107, an ultralow off‐state current of ≈1.2 pA, and an outstanding multi‐bit storage capacity (11 storage states, 546 nC state–1). In addition, the middle BP layer in the multi‐heterojunction enables broadband spectrum distinction (375–1064 nm), together with a high polarization ratio of 8.4. The obtained results represent the significant step toward the high‐density integration of optoelectronic memories with 2D vdWs heterostructures.

Reconfigurable optical memory based on MoS2/QDs mixed-dimensional van der Waals heterostructure

Optical memory unit with the ability to detect and store optical signals is increasingly becoming a crucial part of advanced data communication and image sensing technology. Despite great efforts devoted to develop high-performance optical memory devices based on two-dimensional (2D) material, the photoelectric conversion is still limited to defect-dominant photo-generated carrier trapping/de-trapping process at the interface of 2D materials. Here, a reconfigurable optical memory implanted with photonic programming/electric erasing operation is demonstrated based on MoS2/quantum dots (QDs) mixed-dimensional heterostructure. Unique photoelectric coupling effect between MoS2 and QDs leads to a continuous n-doping on MoS2 channel after light exposure removed, resulting in the generation of persistent photocurrent. Excellent optical memory characteristics such as high programming/erasing ratio, long retention time and stable operation cycles have been achieved and demonstrated to be gate-tunable. Besides, multi-level optical data storage with ten different states is also realized by applying a series of programmable optical signals. Owing to the unique dynamic response of mix-dimensional van der Waals heterostructure to optical and electric signals, our proposed optical memory transistor may pave up a new path to explore photoelectric conversion in low-dimensional system and develop high-performance optoelectronics for a broad range of applications.

Synthesis of nanodiamonds using liquid-phase laser ablation of graphene and its application in resistive random access memory

Nanodiamonds (ND) are carbon particles with a size less than 100 nm, formed by sp3 hybridization of carbon atoms. They have attracted considerable research interest for their potential applications ranging from sensing and bioimaging to quantum computation due to its physical, chemical and surface characteristics. In this work, we report the synthesis of ND from graphene dispersions by liquid-phase laser ablation technique, using an Nd: YAG laser. ND samples exhibit a characteristic photo-absorption at 226 nm, and it shows an excitation dependent emission similar to the carbon dots. Employing Scanning Tunneling Spectroscopy, the bandgap of ND is calculated to be 5.2 eV, and the work-function is around 4.2 eV. Further, we fabricated Resistive switching devices with ND film as the active layer, fluorine-doped tin oxide (FTO) as the bottom and silver (Ag) as the top electrodes. These FTO/ND/Ag devices show excellent memory characteristics with an on-off ratio of 104 and reproducible cycling characteristics, demonstrating its potential for high-density memory applications.

Multibit non-volatile memory based on WS2 transistor with engineered gate stack

In this work, a prototype of a charge-trapping memory device based on two-dimensional WS2 has been fabricated with an engineered gate stack for multilevel non-volatile memory application. A Si/SiO2/ITO/Al2O3/Ta2O5/Al2O3 stack has been successfully integrated with optimized layer thicknesses for enhanced gate control over the WS2 channel and memory performance. The memory cells exhibited a sufficient memory window, fast programming and erasing speed, and excellent memory retention and endurance. Moreover, stable and discrete memory states have been achieved at small gate voltages. Such excellent memory characteristics originated from the intrinsic properties of the atomically thin WS2 material and the engineered gate stack with clean and robust interfaces. The better thermal stability, higher permittivity, deeper trap level, and relatively smaller bandgap of the Ta2O5 dielectric than other commonly used dielectrics such as SiO2 and Al2O3 also contribute to the memory reliability, which is very attractive for future information and data storage applications.

Lead-free (K,Na)NbO3 Thick Films for Flexible Non-volatile Memory Applications

We report the sol-gel fabrication and electrical characterization of flexible (K,Na)NbO3 (KNN) thick films. Muscovite mica allows the growth of high-quality polycrystalline KNN thick films with flexible functionality. Because of the trade-off between increase of grain-size and volatilization of alkaline ions, the electrical polarization is optimized at certain temperature of 720 °C. The remnant and saturation polarization of flexible KNN films were recorded to Pr = 10.3 μC/cm2 and Ps = 23.3 μC/cm2, respectively, which are quite close to those of rigid films with the same chemical compositions. The KNN thick films are bendable even up to bending radius of R = 3.1 mm, and the Pr and Ps at bending states are almost the same as compared to those at unbending state. Even in the convex and concave bending, the KNN thick films show excellent non-volatile memory characteristics. The Pr is almost thesameevenafter the108 times of switching and the 104 sec of retention.