A5052029742- Advanced Memory and Neural Computing
- Nanowire Synthesis and Applications
- Ferroelectric and Negative Capacitance Devices
- Neuroscience and Neural Engineering
- Semiconductor materials and devices
- CCD and CMOS Imaging Sensors
- Advancements in Semiconductor Devices and Circuit Design
- Photoreceptor and optogenetics research
- Adversarial Robustness in Machine Learning
- Semiconductor materials and interfaces
- Advanced Malware Detection Techniques
- Advanced Thermoelectric Materials and Devices
- Information and Cyber Security
- Ethics and Social Impacts of AI
- Neural dynamics and brain function
- Electronic and Structural Properties of Oxides
- Semiconductor Quantum Structures and Devices
- Molecular Junctions and Nanostructures
- Cybersecurity and Cyber Warfare Studies
- Transition Metal Oxide Nanomaterials
- Network Security and Intrusion Detection
- ZnO doping and properties
- Thermal properties of materials
- GaN-based semiconductor devices and materials
- Nuclear Physics and Applications
Center for Security and Emerging Technology
2021-2023
RAND Corporation
2019-2020
Georgetown University
2020
Sandia National Laboratories
2013-2016
Sandia National Laboratories California
2013-2014
Hewlett-Packard (United States)
2013
University of California, Santa Cruz
2009-2012
Ames Research Center
2009-2012
High‐performance memristors based on AlN films have been demonstrated, which exhibit ultrafast ON/OFF switching times (≈85 ps for microdevices with waveguide) and relatively low current (≈15 μA 50 nm devices). Physical characterizations are carried out to understand the device mechanism, rationalize speed energy performance. The formation of an Al‐rich conduction channel through layer is revealed. motion positively charged nitrogen vacancies likely responsible observed switching.
With the recent wave of progress in artificial intelligence (AI) has come a growing awareness large-scale impacts AI systems, and recognition that existing regulations norms industry academia are insufficient to ensure responsible development. In order for developers earn trust from system users, customers, civil society, governments, other stakeholders they building responsibly, will need make verifiable claims which can be held accountable. Those outside given organization also effective...
We present resistive switching model for TaOx memristors, which demonstrates that the radius of a tantalum rich conducting filament is state variable controlling resistance. The tracks flux individual oxygen ions and permits derivation solving dynamical static equations. Model predictions ON/OFF were tested experimentally with devices shown to be in close quantitative agreement, including observed transition from linear non-linear conduction between RON ROFF. This work presents dynamics...
The steady-state solution of filamentary memristive switching may be derived directly from the heat equation, modelling vertical and radial flow. This is shown to provide a continuous accurate description evolution filament radius, composition, flow, temperature during switching, apply large range materials experimental time-scales. As service our authors readers, this journal provides supporting information supplied by authors. Such are peer reviewed re-organized for online delivery, but...
Foundation models could eventually introduce several pathways for undermining state security: accidents, inadvertent escalation, unintentional conflict, the proliferation of weapons, and interference with human diplomacy are just a few on long list. The Confidence-Building Measures Artificial Intelligence workshop hosted by Geopolitics Team at OpenAI Berkeley Risk Security Lab University California brought together multistakeholder group to think through tools strategies mitigate potential...
The effects of radiation on memristors created using tantalum oxide and titanium are compared. Both technologies show changes in resistance when exposed to 800 keV Ta ion irradiation at fluences above <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$10^{10}~\hbox{cm}^{\hbox{-}2}$</tex> </formula> . Notation="TeX">${\rm TaO}_{\rm x}$</tex></formula> a gradual reduction high whereas TiO}_2$</tex>...
A major class of resistive memory devices is based on transition metal oxides, where mobile oxygen vacancies allow these to exhibit multiple resistance states. Ta2O5 in particular have recently demonstrated impressive endurance and forming-free results. Deposition substoichiometric Ta2Ox (x &lt; 5) films a critical process order produce the required devices. This paper describes physical vapor deposition (PVD) reactive sputtering deposit films. The desired film stoichiometry achieved by...
Tantalum oxide has shown promising electrical switching characteristics for memristor devices. Consequently, a number of reports have investigated the behavior TaOx thin films. Some effort been made to characterize composition films and it is known that there must be an optimal stoichiometry where forming are optimized. However, many previous lack details on methodology used identifying chemistry X-ray photoelectron spectroscopy most commonly technique; however, peak fitting routines vary...
Standard deposition processes for depositing ReRAM oxides utilize mass flow of reactive gas to control stoichiometry and have difficulty a precisely defined sub-stoichiometry within “forbidden region” where film properties are discontinuous with flow. We show that by maintaining partial pressure this region,” instead flow, we can optimize tantalum oxide device reduce or eliminate the electroforming step. also defining set point as fraction an absolute value be used improve wafer-to-wafer...
Memristive switches are devices which modulate their resistance state depending on the history of applied current and/or voltage, and have substantial technological potential as well scientific interest. In this paper, we review research memristive systems. We many classes switching, physical mechanisms, fabrication operational modes. Next, discuss art experimental modeling/simulation techniques, insight afforded from these approaches. Finally, applications believed fascinating exciting devices.
Resistive random access memory (ReRAM) has become a promising candidate for next-generation high-performance non-volatile that operates by electrically tuning resistance states via modulating vacancy concentrations. We demonstrate wafer-scale process resistive switching in tantalum oxide is completely CMOS compatible. The resulting devices are forming-free and with greater than 1x10 5 cycle endurance.
We report resistive switching data in TaOx memristors displaying signatures of multi-filament modes and present a technique which enables the characterization evolution multiple filaments within single device during switching, including their temperature, heat flow, conductivity, time evolving areas. Using geometrically defined equivalent circuit, we resolve individual current/voltage values each filament demonstrate that curves collapse onto common curve determined by analytical...
Ensembles that contain two types (zincblende and wurtzite) of indium phosphide nanowires grown on non-single crystalline surfaces were studied by micro-photoluminescence micro-Raman spectroscopy at various low temperatures. The obtained spectra are discussed with the emphasis effects differing lattice types, geometries, crystallographic orientations present within an ensemble surfaces. In photoluminescence spectra, a typical Varshni dependence band gap energy temperature was observed for...
We discuss the thermal effects on scaling, retention, and error rate in filamentary resistive memories from a theoretical perspective using an analytical approach. Starting heat equation, we derive temperature profile surrounding memory device calculate its effect neighboring devices. outline engineering tradeoffs that are expected with continued such as retention power use per device. Based our calculations, expect scaling to continue well below 10 nm, but of heating devices needs be...