Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Direct measurement of nanoscale filamentary hot spots in resistive memory devices.

ABSTRACT: Resistive random access memory (RRAM) is an important candidate for both digital, high-density data storage and for analog, neuromorphic computing. RRAM operation relies on the formation and rupture of nanoscale conductive filaments that carry enormous current densities and whose behavior lies at the heart of this technology. Here, we directly measure the temperature of these filaments in realistic RRAM with nanoscale resolution using scanning thermal microscopy. We use both conventional metal and ultrathin graphene electrodes, which enable the most thermally intimate measurement to date. Filaments can reach 1300°C during steady-state operation, but electrode temperatures seldom exceed 350°C because of thermal interface resistance. These results reveal the importance of thermal engineering for nanoscale RRAM toward ultradense data storage or neuromorphic operation.

SUBMITTER: Deshmukh S

PROVIDER: S-EPMC8967235 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Direct measurement of nanoscale filamentary hot spots in resistive memory devices.

Deshmukh Sanchit S Rojo Miguel Muñoz MM Yalon Eilam E Vaziri Sam S Koroglu Cagil C Islam Raisul R Iglesias Ricardo A RA Saraswat Krishna K Pop Eric E

Science advances 20220330 13

Resistive random access memory (RRAM) is an important candidate for both digital, high-density data storage and for analog, neuromorphic computing. RRAM operation relies on the formation and rupture of nanoscale conductive filaments that carry enormous current densities and whose behavior lies at the heart of this technology. Here, we directly measure the temperature of these filaments in realistic RRAM with nanoscale resolution using scanning thermal microscopy. We use both conventional metal a ...[more]

PMID: 35353574

Similar Datasets

Spatially-Resolved Thermometry of Filamentary Nanoscale Hot Spots in TiO<sub>2</sub> Resistive Random Access Memories to Address Device Variability.

Project description:Resistive random access memories (RRAM), based on the formation and rupture of conductive nanoscale filaments, have attracted increased attention for application in neuromorphic and in-memory computing. However, this technology is, in part, limited by its variability, which originates from the stochastic formation and extreme heating of its nanoscale filaments. In this study, we used scanning thermal microscopy (SThM) to assess the effect of filament-induced heat spreading on the surface of metal oxide RRAMs with different device designs. We evaluate the variability of TiO2 RRAM devices with area sizes of 2 × 2 and 5 × 5 μm2. Electrical characterization shows that the variability indicated by the standard deviation of the forming voltage is ∼2 times larger for 5 × 5 μm2 devices than for the 2 × 2 μm2 ones. Further knowledge on the reason for this variability is gained through the SThM thermal maps. These maps show that for 2 × 2 μm2 devices the formation of one filament, i.e., hot spot at the device surface, happens reliably at the same location, while the filament location varies for the 5 × 5 μm2 devices. The thermal information, combined with the electrical, interfacial, and geometric characteristics of the device, provides additional insights into the operation and variability of RRAMs. This work suggests thermal engineering and characterization routes to optimize the efficiency and reliability of these devices.

| S-EPMC10537448 | biostudies-literature

Scanning Thermal Microscopy Method for Self-Heating in Nonlinear Devices and Application to Filamentary Resistive Random-Access Memory.

Project description:Devices with a highly nonlinear resistance-voltage relationship are candidates for neuromorphic computing, which can be achieved by highly temperature dependent processes like ion migration. To explore the thermal properties of such devices, Scanning Thermal Microscopy (SThM) can be employed. However, due to the nonlinearity, the high resolution and quantitative method of AC-modulated SThM cannot readily be used. To this end, an extended nonequilibrium scheme for temperature measurement using SThM is proposed, with which the self-heating of nonlinear devices is studied without the need for calibrating the tip-sample contact for a specific material combination, geometry or roughness. Both a DC and an AC voltage are applied to the device, triggering a periodic temperature rise, which enables the simultaneous calculation of the tip-sample thermal resistance and the device temperature rise. The method is applied to HfO2-based RRAM devices, in which the kinetic processes of filamentary switching are governed by temperature. We image temperature and propagation of thermal waves and extract properties like the number of current filaments, thermal confinement and thermal cross-talk.

| S-EPMC11823610 | biostudies-literature

Spatially Resolved Thermometry of Resistive Memory Devices.

Project description:The operation of resistive and phase-change memory (RRAM and PCM) is controlled by highly localized self-heating effects, yet detailed studies of their temperature are rare due to challenges of nanoscale thermometry. Here we show that the combination of Raman thermometry and scanning thermal microscopy (SThM) can enable such measurements with high spatial resolution. We report temperature-dependent Raman spectra of HfO2, TiO2 and Ge2Sb2Te5 (GST) films, and demonstrate direct measurements of temperature profiles in lateral PCM devices. Our measurements reveal that electrical and thermal interfaces dominate the operation of such devices, uncovering a thermal boundary resistance of 28 ± 8 m2K/GW at GST-SiO2 interfaces and an effective thermopower 350 ± 50 µV/K at GST-Pt interfaces. We also discuss possible pathways to apply Raman thermometry and SThM techniques to nanoscale and vertical resistive memory devices.

| S-EPMC5681698 | biostudies-literature

Quantum conductance in silicon oxide resistive memory devices.

Project description:Resistive switching offers a promising route to universal electronic memory, potentially replacing current technologies that are approaching their fundamental limits. In many cases switching originates from the reversible formation and dissolution of nanometre-scale conductive filaments, which constrain the motion of electrons, leading to the quantisation of device conductance into multiples of the fundamental unit of conductance, G0. Such quantum effects appear when the constriction diameter approaches the Fermi wavelength of the electron in the medium - typically several nanometres. Here we find that the conductance of silicon-rich silica (SiOx) resistive switches is quantised in half-integer multiples of G0. In contrast to other resistive switching systems this quantisation is intrinsic to SiOx, and is not due to drift of metallic ions. Half-integer quantisation is explained in terms of the filament structure and formation mechanism, which allows us to distinguish between systems that exhibit integer and half-integer quantisation.

| S-EPMC3776960 | biostudies-literature

Memristive tonotopic mapping with volatile resistive switching memory devices.

Project description:To reach the energy efficiency and the computing capability of biological neural networks, novel hardware systems and paradigms are required where the information needs to be processed in both spatial and temporal domains. Resistive switching memory (RRAM) devices appear as key enablers for the implementation of large-scale neuromorphic computing systems with high energy efficiency and extended scalability. Demonstrating a full set of spatiotemporal primitives with RRAM-based circuits remains an open challenge. By taking inspiration from the neurobiological processes in the human auditory systems, we develop neuromorphic circuits for memristive tonotopic mapping via volatile RRAM devices. Based on a generalized stochastic device-level approach, we demonstrate the main features of signal processing of cochlea, namely logarithmic integration and tonotopic mapping of signals. We also show that our tonotopic classification is suitable for speech recognition. These results support memristive devices for physical processing of temporal signals, thus paving the way for energy efficient, high density neuromorphic systems.

| S-EPMC10985068 | biostudies-literature

Evidence of Filamentary Switching in Oxide-based Memory Devices via Weak Programming and Retention Failure Analysis.

Project description:Further progress in high-performance microelectronic devices relies on the development of novel materials and device architectures. However, the components and designs that are currently in use have reached their physical limits. Intensive research efforts, ranging from device fabrication to performance evaluation, are required to surmount these limitations. In this paper, we demonstrate that the superior bipolar resistive switching characteristics of a CeO2:Gd-based memory device can be manipulated by means of UV radiation, serving as a new degree of freedom. Furthermore, the metal oxide-based (CeO2:Gd) memory device was found to possess electrical and neuromorphic multifunctionalities. To investigate the underlying switching mechanism of the device, its plasticity behaviour was studied by imposing weak programming conditions. In addition, a short-term to long-term memory transition analogous to the forgetting process in the human brain, which is regarded as a key biological synaptic function for information processing and data storage, was realized. Based on a careful examination of the device's retention behaviour at elevated temperatures, the filamentary nature of switching in such devices can be understood from a new perspective.

| S-EPMC4555098 | biostudies-literature

Stimulated Ionic Telegraph Noise in Filamentary Memristive Devices.

Project description:Random telegraph noise is a widely investigated phenomenon affecting the reliability of the reading operation of the class of memristive devices whose operation relies on formation and dissolution of conductive filaments. The trap and the release of electrons into and from defects surrounding the filament produce current fluctuations at low read voltages. In this work, telegraphic resistance variations are intentionally stimulated through pulse trains in HfO2-based memristive devices. The stimulated noise results from the re-arrangement of ionic defects constituting the filament responsible for the switching. Therefore, the stimulated noise has an ionic origin in contrast to the electronic nature of conventional telegraph noise. The stimulated noise is interpreted as raising from a dynamic equilibrium establishing from the tendencies of ionic drift and diffusion acting on the edges of conductive filament. We present a model that accounts for the observed increase of noise amplitude with the average device resistance. This work provides the demonstration and the physical foundation for the intentional stimulation of ionic telegraph noise which, on one hand, affects the programming operations performed with trains of identical pulses, as for neuromorphic computing, and on the other hand, it can open opportunities for applications relying on stochastic processes in nanoscaled devices.

| S-EPMC6465356 | biostudies-literature

Electrochemical Oxidation Induced Multi-Level Memory in Carbon-Based Resistive Switching Devices.

Project description:In this work, we report for the first time the electrochemical oxidation as a technique to improve the electrical performances of carbon-based resistive switching devices. The devices obtained through the anodic oxidation of carbon-structures possess superior electrical performances i.e. a 3-level memory behavior and an ON/OFF ratio two order of magnitude higher than the non-oxidized carbon-based devices. It is demonstrated that the chemical composition of the carbon structures (i.e. percentage of oxygen groups, sp2 and sp3 carbon atoms) plays a key role in the improvement of the carbon-based devices. The electrochemical oxidation allows the possibility to control the oxidation degree, and therefore, to tailor the devices electrical performances. We demonstrated that the resistive switching behavior in the electrochemically oxidized devices is originated from the formation of conductive filament paths, which are built from the oxygen vacancies and structural defects of the anodic oxidized carbon materials. The novelty of this work relies on the anodic oxidation as a time- and cost-effective technique that can be employed for the engineering and improvement of the electrical performances of next generation carbon-based resistive switching devices.

| S-EPMC6367418 | biostudies-literature

Conduction Mechanisms on High Retention Annealed MgO-based Resistive Switching Memory Devices.

Project description:We report on the conduction mechanisms of novel Ru/MgO/Cu and Ru/MgO/Ta resistive switching memory (RSM) devices. Current-voltage (I-V) measurements revealed Schottky emission (SE) as the dominant conduction mechanism in the high resistance state (HRS), which was validated by varying temperatures and transmission electron microscopy (TEM) results. Retention of more than 10 years at 85 °C was obtained for both Ru/MgO/Ta and Ru/MgO/Cu RSM devices. In addition, annealing processes greatly improved the consistency of HRS and LRS switching paths from cycle to cycle, exhibiting an average ON/OFF ratio of 102. Further TEM studies also highlighted the difference in crystallinity between different materials in Ru/MgO/Cu RSM devices, confirming Cu filament identification which was found to be 10 nm in width.

| S-EPMC6170501 | biostudies-literature

Direct Measurement of Oxygen Mass Transport at the Nanoscale.

Project description:Tuning oxygen mass transport properties at the nanoscale offers a promising approach for developing high performing energy materials. A number of strategies for engineering interfaces with enhanced oxygen diffusivity and surface exchange have been proposed. However, the origin and the magnitude of such local effects remain largely undisclosed to date due to the lack of direct measurement tools with sufficient resolution. In this work, atom probe tomography with sub-nanometer resolution is used to study oxygen mass transport on oxygen-isotope exchanged thin films of lanthanum chromite. A direct 3D visualization of nanoscaled highly conducting oxygen incorporation pathways along grain boundaries, with reliable quantification of the oxygen kinetic parameters and correlative link to local chemistries, is presented. Combined with finite element simulations of the exact nanostructure, isotope exchange-atom probe tomography allowed quantifying an enhancement in the grain boundary oxygen diffusivity and in the surface exchange coefficient of lanthanum chromite of about 4 and 3 orders of magnitude, respectively, compared to the bulk. This remarkable increase of the oxygen kinetics in an interface-dominated material is unambiguously attributed to grain boundary conduction highways thanks to the use of a powerful technique that can be straightforwardly extended to the study of currently inaccessible multiple nanoscale mass transport phenomena.

| S-EPMC11468452 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data