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The susceptibility of TaOx-based memristors to high dose rate ionizing radiation and total ionizing dose

IEEE Transactions on Nuclear Science

McLain, Michael L.; Hjalmarson, Harold P.; Sheridan, Timothy J.; Mickel, Patrick R.; Hanson, Donald J.; McDonald, Joseph K.; Hughart, David R.; Marinella, Matthew J.

This paper investigates the effects of high dose rate ionizing radiation and total ionizing dose (TID) on tantalum oxide (TaOx) memristors. Transient data were obtained during the pulsed exposures for dose rates ranging from approximately 5.0 × 107rad(Si)/s to 4.7 × 108rad(Si)/s and for pulse widths ranging from 50 ns to 50 μs. The cumulative dose in these tests did not appear to impact the observed dose rate response. Static dose rate upset tests were also performed at a dose rate of ∼3.0 × 108rad(Si)/s. This is the first dose rate study on any type of memristive memory technology. In addition to assessing the tolerance of TaOx memristors to high dose rate ionizing radiation, we also evaluated their susceptibility to TID. The data indicate that it is possible for the devices to switch from a high resistance off-state to a low resistance on-state in both dose rate and TID environments. The observed radiation-induced switching is dependent on the irradiation conditions and bias configuration. Furthermore, the dose rate or ionizing dose level at which a device switches resistance states varies from device to device; the enhanced susceptibility observed in some devices is still under investigation. Numerical simulations are used to qualitatively capture the observed transient radiation response and provide insight into the physics of the induced current/voltages.

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Development characterization and modeling of a TaOx ReRAM for a neuromorphic accelerator

Marinella, Matthew J.; Mickel, Patrick R.; Lohn, Andrew L.; Hughart, David R.; Bondi, Robert J.; Mamaluy, Denis M.; Hjalmarson, Harold P.; Stevens, James E.; Decker, Seth D.; Apodaca, Roger A.; Evans, Brian R.; Aimone, James B.; Rothganger, Fredrick R.; James, Conrad D.; DeBenedictis, Erik

This report discusses aspects of neuromorphic computing and how it is used to model microsystems.

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LDRD project 151362 : low energy electron-photon transport

Kensek, Ronald P.; Hjalmarson, Harold P.; Magyar, Rudolph J.; Bondi, Robert J.

At sufficiently high energies, the wavelengths of electrons and photons are short enough to only interact with one atom at time, leading to the popular %E2%80%9Cindependent-atom approximation%E2%80%9D. We attempted to incorporate atomic structure in the generation of cross sections (which embody the modeled physics) to improve transport at lower energies. We document our successes and failures. This was a three-year LDRD project. The core team consisted of a radiation-transport expert, a solid-state physicist, and two DFT experts.

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High-voltage atmospheric breakdown across intervening rutile dielectrics

Simpson, Sean S.; Coats, Rebecca S.; Hjalmarson, Harold P.; Jorgenson, Roy E.; Pasik, Michael F.

This report documents work conducted in FY13 on electrical discharge experiments performed to develop predictive computational models of the fundamental processes of surface breakdown in the vicinity of high-permittivity material interfaces. Further, experiments were conducted to determine if free carrier electrons could be excited into the conduction band thus lowering the effective breakdown voltage when UV photons (4.66 eV) from a high energy pulsed laser were incident on the rutile sample. This report documents the numerical approach, the experimental setup, and summarizes the data and simulations. Lastly, it describes the path forward and challenges that must be overcome in order to improve future experiments for characterizing the breakdown behavior for rutile.

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Results 26–50 of 109
Results 26–50 of 109