Nondestructive Readout Research Articles

Super-Lamination HZO/ZrO₂/HZO of Ferroelectric Memcapacitors With Morphotropic Phase Boundary (MPB) for High Capacitive Ratio and Non-Destructive Readout

Super-Lamination HZO/ZrO₂/HZO of Ferroelectric Memcapacitors With Morphotropic Phase Boundary (MPB) for High Capacitive Ratio and Non-Destructive Readout

Achieving Single-Electron Sensitivity at Enhanced Speed in Fully Depleted CCDs with Double-Gate MOSFETs.

We introduce a new output amplifier for fully depleted thick p-channel CCDs based on double-gate MOSFETs. The charge amplifier is an n-type MOSFET specifically designed and operated to couple the fully depleted CCD with high charge-transfer efficiency. The junction coupling between the CCD and MOSFET channels has enabled high sensitivity, demonstrating readout noise of 0.74 e_{rms}^{-}/pix in one pixel charge measurement. We have also demonstrated the nondestructive readout capability of the device. Single-electron and single-photon per pixel counting in the entire CCD pixel array has been made possible through the averaging of ten samples, achieving 0.15 e_{rms}^{-}/pix in a pixel readout time of 2.74ms. We have demonstrated fully depleted CCD readout with better performance than the floating diffusion and floating gate amplifiers available today, in both single and multisampling regimes, boasting at least 6 times the speed of floating gate amplifiers.

Precise control and non-destructive readout of quantum states of ion motion

Precise control and non-destructive readout of quantum states of ion motion

A memristive-photoconductive transduction methodology for accurately nondestructive memory readout

Crossbar resistive memory architectures enable high-capacity storage and neuromorphic computing, accurate retrieval of the stored information is a prerequisite during read operation. However, conventional electrical readout normally suffer from complicated process, inaccurate and destructive reading due to crosstalk effect from sneak path current. Here we report a memristive-photoconductive transduction (MPT) methodology for precise and nondestructive readout in a memristive crossbar array. The individual devices present dynamic filament form/fuse for resistance modulation under electric stimulation, which leads to photogenerated carrier transport for tunable photoconductive response under subsequently light pulse stimuli. This coherent signal transduction can be used to directly detect the memorized on/off states stored in each cell, and a prototype 4 * 4 crossbar memories has been constructed and validated for the fidelity of crosstalk-free readout in recall process.

Controllable Manipulation of Semifluxon States in Phase-Shifted Josephson Junctions.

The utilization of Josephson vortices as information carriers in superconducting digital electronics is hindered by the lack of reliable displacement and localization mechanisms. In this Letter, we experimentally investigate planar Nb junctions with an intrinsic phase shift and nonreciprocity induced by trapped Abrikosov vortices. We demonstrate that the entrance of a single Josephson vortex into such junctions triggers the switching between metastable ±π semifluxon states. We showcase controllable manipulation between these states using short current pulses and achieve a nondestructive readout by a nearby junction. Our observations pave the way toward ultrafast and energy-efficient digital Josephson electronics.

Transistors with ferroelectric ZrXAl1−XOY crystallized by ZnO growth for multi-level memory and neuromorphic computing

Ferroelectric (FE) field-effect transistors are interesting for their non-destructive readout characteristic and energy efficiency but are difficult to integrate on silicon platforms. Here, FE ZrXAl1−XOY (ZAO) is demonstrated by compressive strain in contact with ZnO. The metal-ferroelectric-semiconductor-metal capacitor exhibits a substantial remnant polarization of 15.2 µC cm−2, along with a bowknot-like anti-clockwise hysteresis in the capacitance curves. The FE-ZAO gated ZnO thin-film transistor presents a large memory window (3.84 V), low subthreshold swing (55 mV dec−1), high ION/IOFF ratio (≈108), and low off-state current (≈1 pA). The grazing incidence X-ray diffraction and scanning transmission electron microscopy analyses reveal the ferroelectric rhombohedral phase (space group R3m) in the nanocrystal ZAO, containing an angle of ≈71.7° between the [111] and [11-1] directions with d111-spacing of 3.037 Å and d11-1-spacing of 2.927 Å. Finally, the memory and neuromorphic applications are analyzed by demonstrating multi-level memory and synaptic weight performance with a high learning accuracy of 91.82%.

Ferroelectric tunnel junctions: promise, achievements and challenges

Abstract Ferroelectric tunnel junctions (FTJs) have been the subject of ongoing research interest due to its fast operation based on the spontaneous polarization direction of ultrathin ferroelectrics and its simple two-terminal structure. Due to the advantages of FTJs, such as non-destructive readout, fast operation speed, low energy consumption, and high-density integration, they have recently been considered a promising candidate for non-volatile next-generation memory. These characteristics are essential to meet the increasing demand for high-performance memory in modern computing systems. In this review, we explore the basic principles and structures of FTJs and clarify the elements necessary for the successful fabrication and operation of FTJs. Then, we focus on the recent progress in perovskite oxide, fluorite, 2-dimensional van der Waals, and polymer-based FTJs and discuss ferroelectric materials expected to be available for FTJs use in the future. We highlight various functional device applications, including non-volatile memories, crossbar arrays, and synapses, utilizing the advantageous properties of ferroelectrics. Lastly, we address the challenges that FTJ devices currently face and propose a direction for moving forward.

Binarized neural network of diode array with high concordance to vector–matrix multiplication

In this study, a binarized neural network (BNN) of silicon diode arrays achieved vector–matrix multiplication (VMM) between the binarized weights and inputs in these arrays. The diodes that operate in a positive-feedback loop in their p+-n-p-n+ device structure possess steep switching and bistable characteristics with an extremely low subthreshold swing (below 1 mV) and a high current ratio (approximately 108). Moreover, the arrays show a self-rectifying functionality and an outstanding linearity by an R-squared value of 0.99986, which allows to compose a synaptic cell with a single diode. A 2 × 2 diode array can perform matrix multiply-accumulate operations for various binarized weight matrix cases with some input vectors, which is in high concordance with the VMM, owing to the high reliability and uniformity of the diodes. Moreover, the disturbance-free, nondestructive readout, and semi-permanent holding characteristics of the diode arrays support the feasibility of implementing the BNN.

Impact of HfO2 Dielectric Layer Placement in Hf0.5Zr0.5O2‐Based Ferroelectric Tunnel Junctions for Neuromorphic Applications

AbstractThe use of Hf0.5Zr0.5O2 (HZO) films within hafnia‐based ferroelectric tunnel junctions (FTJ) presents a promising avenue for next‐generation non‐volatile memory devices. HZO exhibits excellent ferroelectric properties, ultra‐thinness, low power consumption, nondestructive readout, and compatibility with silicon devices. In this study, Mo/HZO/n+ Si devices are investigated, incorporating a 1 nm HfO2 dielectric layer at the top and bottom of the HZO ferroelectric layer. Comparing the FTJ device configurations, it is observed that the metal‐ferroelectric‐dielectric‐semiconductor (MFIS) outperforms the metal‐dielectric‐ferroelectric‐semiconductor (MIFS) in terms of ferroelectricity, displaying a high 2Pr value of ≈69 µC cm−2. Additionally, MFIS exhibits lower leakage current, higher tunneling electro‐resistance ratio, and a thin dead layer during short pulse switching, as confirmed through DC double sweeping of I−V characteristics. The modified half‐bias scheme demonstrates a maximum array size of 191 for MFIS, showcasing its superior performance over MIFS. Synaptic characteristics, including potentiation, depression, paired‐pulse facilitation, spike‐rate‐dependent plasticity, and excitatory postsynaptic current, are measured using MFIS, highlighting its outstanding ferroelectric properties. As a physical reservoir, the FTJ device implements 16 states of 4 bits in reservoir computing. Finally, pattern recognition using a deep learning neural network achieves high accuracy with using the Modified National Institute of Standards and Technology dataset.

Read Operation Mechanism of Feedback Field-Effect Transistors with Quasi-Nonvolatile Memory States.

In this study, the read operation of feedback field-effect transistors (FBFETs) with quasi-nonvolatile memory states was analyzed using a device simulator. For FBFETs, write pulses of 40 ns formed potential barriers in their channels, and charge carriers were accumulated (depleted) in these channels, generating the memory state "State 1 (State 0)". Read pulses of 40 ns read these states with a retention time of 3 s, and the potential barrier formation and carrier accumulation were influenced by these read pulses. The potential barriers were analyzed, using junction voltage and current density to explore the memory states. Moreover, FBFETs exhibited nondestructive readout characteristics during the read operation, which depended on the read voltage and pulse width.

Demonstrating repetitive non-destructive readout with SiSeRO devices

Demonstrating repetitive non-destructive readout with SiSeRO devices

Alanine/EPR dosimetry for mailed intercomparison at ocular proton therapy facilities-preliminary results for three centres for irradaitions at CCB IFJ PAN eyeline.

Quality control of therapeutic photon beams in the form of postal dose audits based on passive dosemeters is widely used in photon radiotherapy. On the other hand, no standardised dosimetry audit programme for proton centres has been established in Europe so far. We evaluated alanine/EPR dosimetry systems developed at the Istituto Superiore di Sanità (Italy), the Hasselt Universiteit (Belgium) and the Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences (Poland) for their applicability as a potential tool for routine mailed dose audits of passively scattered therapeutic proton beams. The evaluation was carried out in the form of an intercomparison. Dosemeters were irradiated in the 70MeV proton beam at ocular proton therapy facility in the Cyclotron Centre Bronowice at the Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences in Krakow. A very good agreement was found between the dose measured by three laboratories and the delivered dose determined with an ionisation chamber. This, together with the inherent properties of alanine, such as non-destructive readout, tissue equivalence, weak energy dependence, dose rate independence and insignificant fading, makes alanine a good candidate for a dosemeter used in postal auditing in proton ocular radiotherapy.

Dynamics of Dispersive Measurements of Flux-Qubit States: Energy-Level Splitting Connected to Quantum Wave Mechanics.

Superconducting flux qubits have many advantages as a storage of quantum information, such as broad range tunability of frequency, small-size fabricability, and high controllability. In the flux qubit-oscillator, qubits are connected to SQUID resonators for the purpose of performing dispersive non-destructive readouts of qubit signals with high fidelity. In this work, we propose a theoretical model for analyzing quantum characteristics of a flux qubit-oscillator on the basis of quantum solutions obtained using a unitary transformation approach. The energy levels of the combined system (qubit + resonator) are analyzed in detail. Equally spaced each energy level of the resonator splits into two parts depending on qubit states. Besides, coupling of the qubit to the resonator brings about an additional modification in the split energy levels. So long as the coupling strength and the tunnel splitting are not zero but finite values, the energy-level splitting of the resonator does not disappear. We conclude that quantum nondemolition dispersive measurements of the qubit states are possible by inducing bifurcation of the resonator states through the coupling.

Design and Simulation Analysis of a 3TnC MLC FeRAM Using a Nondestructive Readout and Offset-Canceled Sense Amplifier for High-Density Storage Applications.

Hf0.5Zr0.5O2-based multi-level cell (MLC) ferroelectric random-access memory (FeRAM) has great potential for high-density storage applications. However, it is usually limited by the issues of a small operation margin and a large input offset. The study of circuit design and optimization for MLC FeRAM is necessary to solve these problems. In this work, we propose and simulate a configuration for a Hf0.5Zr0.5O2-based 3TnC MLC FeRAM macro circuit, which also presents a high area efficiency of 12F2 for each bit. Eight polarization states can be distinguished in a single fabricated Hf0.5Zr0.5O2-based memory device for potential MLC application, which is also simulated by a SPICE model for the subsequent circuit design. Therein, a nondestructive readout approach is adopted to expand the reading margin to 450 mV between adjacent storage levels, while a capacitorless offset-canceled sense amplifier (SA) is designed to reduce the offset voltage to 20 mV, which improves the readout reliability of multi-level states. Finally, a 4 Mb MLC FeRAM macro is simulated and verified using a GSMC 130 nm CMOS process. This study provides the foundation of circuit design for the practical fabrication of a Hf0.5Zr0.5O2-based MLC FeRAM chip in the future, which also suggests its potential for high-density storage applications.

Design of Max Pooling Operation Circuit for Binarized Neural Networks Using Single-Flux-Quantum Circuit

For the binary neural network (BNN), We design a max pooling operation circuit (MPOC) using single-flux-quantum circuits based on the multiple data comparators. To continuously compare multiple data and find the maximum value, the multiple data comparator uses the internal state of non-destructive read-out (NDRO) flip-flop and NDRO with complementary outputs to store the maximum value. The MPOC is designed with a gate-level pipeline architecture and uses the internal state to store the maximum value, avoiding the use of feedback loops or tree structures when comparing multiple data. Therefore, the area of the MPOC is reduced by approximately 74% compared to the conventional MPOC using many shift registers with tree structures. The throughput is approximately 21.2 times higher and the area is reduced by 22.1% when compared with the conventional MPOC using feedback loops. We designed an MPOC with 2878 Josephson junctions using a 10 kA/cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{2}$</tex-math></inline-formula> Nb process. The proposed circuit can be used for pooling operations of any size after a 1-channel 3x3 convolutional layer, which accelerates the forward propagation process of binary neural networks (BNNs). Simulation results show that the MPOC can perform pooling operations continuously at the frequency of 50 GHz.

Randomized Benchmarking Using Nondestructive Readout in a Two-Dimensional Atom Array.

Neutral atoms are a promising platform for scalable quantum computing, however, prior demonstration of high fidelity gates or low-loss readout methods have employed restricted numbers of qubits. Using randomized benchmarking of microwave-driven single-qubit gates, we demonstrate average gate errors of 7(2)×10^{-5} on a 225 site atom array using conventional, destructive readout. We further demonstrate a factor of 1.7 suppression of the primary measurement errors via low-loss, nondestructive, and state-selective readout on 49 sites while achieving gate errors of 2(9)×10^{-4}.

Si-integrated lanthanide-doped ferroelectrics for a photomemory based on a photochromic reaction.

We describe a Si-integrated photochromic photomemory based on lanthanide-doped ferroelectric Na0.5Bi2.5Nb2O9:Er3+ (NBN:Er) thin films. We show that upconversion emission can be effectively modulated by up to 78% through the photochromic reaction. The coupling between lanthanide upconversion emission and the photochromic effect ensures rewritable and nondestructive readout characteristics. Moreover, integrating photochromic thin films with Si would benefit from its compatibility with the mature complementary metal-oxide semiconductor (CMOS) technique. These results demonstrate the opportunity to develop more compact photochromic photomemories and related photonic devices.

Size-dependent polarization retention in ferroelectric BiFeO3 domain wall memories

Reliable polarization retention in a single crystal-like ferroelectric thin film is crucial for the effective implementation of ferroelectric domain wall (DW) memories. This ensures that the saved information can be non-destructively read out by identifying the resistive state of the memory with a voltage signal below the coercive voltage (Vc) of the ferroelectric film. However, stabilizing a small volume of switched polarization for ultra-high-density information storage applications is still challenging due to its back-switching behavior at zero electric field. In this study, we investigated the polarization retention of ferroelectric BiFeO3 (BFO) thin film devices with size-variable Pt electrodes. With the scaling down of the device size, the switched polarizations became more susceptible to depolarization field and ferroelastic stress arising at the artificially created domain boundary. We found that BFO devices featuring a switched polarization area larger than 7 × 106 nm2 demonstrated both long-term polarization retention and a current rectification ratio of 4.5:1 induced by DW manipulation. As the device size decreases, the retention time of the switched polarization reduces gradually, which results in the disappearance of the device current due to the DW being eliminated by the back-switching of the polarization. A plot was created to illustrate the relationship between the current retention time and the switched polarization area on the surface of the BFO thin films. Furthermore, the unsustainable polarization retention facilitates a higher current rectification ratio of 48:1, which is suitable for non-destructive information readout with a voltage pulse larger than Vc in high-density ferroelectric DW memories.

Electret Molecular Configuration Induced Programmable Photonic Memory for Advanced Logic Operation and Data Encryption

AbstractNonvolatile organic photonic transistor (OPT) memories have attracted widespread attention due to their nondestructive readout, remote controllability, and robust tunability. Developing electrets with similar molecular structures but different memory behaviors and light‐responsive features is crucial for light‐wavelength‐modulated data encryption. However, reported OPT memories have yet to meet this challenge. Here a new electret molecule (“H‐PDI”) is developed via reconfiguring the linear perylene diimide molecule (“L‐PDI”) to a helical shape. Respectively incorporating H‐PDI and L‐PDI into the floating gate layer results to H‐PDI OPT and L‐PDI OPT. Attributing to their remarkably different electronic structures and energy bandgaps, H‐PDI OPT and L‐PDI OPT preferably respond to 405 and 532 nm light irradiation, respectively. Upon electrical programming, data can be written and stored in both memories with good retention features and a high “1”/“0” state current ratio over 105, though the data can only be erased by light with correct wavelengths, rather than the electrical field. Moreover, data stored in a memory array consisting of both H‐PDI OPT and L‐PDI OPT can only be read out by correct inputs, and wrong inputs will lead to highly deceptive outputs. This study provides a general design strategy of OPT for advanced data encryption and protection.

Developing "smart windows" for optical storage and temperature sensing based on KNN transparent ceramics

Smart windows have attracted considerable attention due to their wide applications in optical data storage, switchable sunroof and temperature sensing. The development strategy for smart windows is focused on performance design, enhancement and integration. However, developing integrated multi-functional smart windows in a single material remains a challenge. In this work, we have successfully prepared (K0.5Na0.5)0.95Ba0.04Er0.01NbO3 (4Ba-1Er-KNN) transparent ceramics for potential applications of temperature detection and optical information storage in smart windows. With alternating ultraviolet (UV) illumination and 300 °C thermal stimulation, the prepared 4Ba-1Er-KNN ceramics can not only achieve non-destructive luminescence readout, but also exhibits an ultra-high photochromic (PC) contrast with rapid response time of 1 s. Furthermore, based on the up-conversion (UC) photoluminescence (PL) intensity ratio of Er3+: 2H11/2/4S3/2 thermally coupled levels, excellent low-temperature sensing performance with the maximum relative sensitivity of 0.023 K−1 at 213 K is obtained. The integration between UC PL, PC response and temperature sensing performance makes it possible to develop multi-functional smart windows.