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Determination of recombination radius in Si for binary collision approximation codes

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms

Vizkelethy, Gyorgy V.; Foiles, Stephen M.

Displacement damage caused by ions or neutrons in microelectronic devices can have significant effect on the performance of these devices. Therefore, it is important to predict not only the displacement damage profile, but also its magnitude precisely. Analytical methods and binary collision approximation codes working with amorphous targets use the concept of displacement energy, the energy that a lattice atom has to receive to create a permanent replacement. It was found that this “displacement energy” is direction dependent; it can range from 12 to 32 eV in silicon. Obviously, this model fails in BCA codes that work with crystalline targets, such as Marlowe. Marlowe does not use displacement energy; instead, it uses lattice binding energy only and then pairs the interstitial atoms with vacancies. Then based on the configuration of the Frenkel pairs it classifies them as close, near, or distant pairs, and considers the distant pairs the permanent replacements. Unfortunately, this separation is an ad hoc assumption, and the results do not agree with molecular dynamics calculations. After irradiation, there is a prompt recombination of interstitials and vacancies if they are nearby, within a recombination radius. In order to implement this recombination radius in Marlowe, we used the comparison of MD and Marlowe calculation in a range of ion energies in single crystal silicon target. As a result, the calculations showed that a single recombination radius of ~7.4 Å in Marlowe for a range of ion energies gives an excellent agreement with MD.

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TYPE Journal Article YEAR 2015
DOIOSTI

Mapping of radiation-induced resistance changes and multiple conduction channels in TaOx memristors

IEEE Transactions on Nuclear Science

Hughart, David R.; Pacheco, Jose L.; Lohn, Andrew L.; Mickel, Patrick R.; Bielejec, Edward S.; Vizkelethy, Gyorgy V.; Doyle, Barney L.; Wolfley, Steven L.; Dodd, Paul E.; Shaneyfelt, Marty R.; McLain, Michael L.; Marinella, Matthew J.

The locations of conductive regions in TaOx memristors are spatially mapped using a microbeam and Nanoimplanter by rastering an ion beam across each device while monitoring its resistance. Microbeam irradiation with 800 keV Si ions revealed multiple sensitive regions along the edges of the bottom electrode. The rest of the active device area was found to be insensitive to the ion beam. Nanoimplanter irradiation with 200 keV Si ions demonstrated the ability to more accurately map the size of a sensitive area with a beam spot size of 40 nm by 40 nm. Isolated single spot sensitive regions and a larger sensitive region that extends approximately 300 nm were observed.

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TYPE Conference Poster YEAR 2014
OSTIScopus

Outstanding conference paper award 2014 IEEE nuclear and space radiation effects conference

IEEE Transactions on Nuclear Science

Dodds, Nathaniel A.; Schwank, James R.; Shaneyfelt, Marty R.; Dodd, Paul E.; Doyle, Barney L.; Trinczek, Michael; Blackmore, Ewart W.; Rodbell, Kenneth P.; Reed, Robert A.; Pellish, Jonathan A.; Label, Kenneth A.; Marshall, Paul W.; Swanson, Scot E.; Vizkelethy, Gyorgy V.; Van Deusen, Stuart B.; Sexton, Frederick W.; Martinez, Marino M.

The recipients of the 2014 NSREC Outstanding Conference Paper Award are Nathaniel A. Dodds, James R. Schwank, Marty R. Shaneyfelt, Paul E. Dodd, Barney L. Doyle, Michael Trinczek, Ewart W. Blackmore, Kenneth P. Rodbell, Michael S. Gordon, Robert A. Reed, Jonathan A. Pellish, Kenneth A. LaBel, Paul W. Marshall, Scot E. Swanson, Gyorgy Vizkelethy, Stuart Van Deusen, Frederick W. Sexton, and M. John Martinez, for their paper entitled "Hardness Assurance for Proton Direct Ionization-Induced SEEs Using a High-Energy Proton Beam." For older CMOS technologies, protons could only cause single-event effects (SEEs) through nuclear interactions. Numerous recent studies on 90 nm and newer CMOS technologies have shown that protons can also cause SEEs through direct ionization. Furthermore, this paper develops and demonstrates an accurate and practical method for predicting the error rate caused by proton direct ionization (PDI).

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TYPE Journal Article YEAR 2014
DOIOSTI

Hardness assurance for proton direct ionization-induced SEEs using a high-energy proton beam

IEEE Transactions on Nuclear Science

Dodds, Nathaniel A.; Schwank, James R.; Shaneyfelt, Marty R.; Dodd, Paul E.; Doyle, Barney L.; Trinczek, M.; Blackmore, E.W.; Rodbell, K.P.; Reed, R.A.; Pellish, J.A.; Label, K.A.; Marshall, P.W.; Swanson, Scot E.; Vizkelethy, Gyorgy V.; Van Deusen, Stuart B.; Sexton, Frederick W.; Martinez, Marino M.

The low-energy proton energy spectra of all shielded space environments have the same shape. This shape is easily reproduced in the laboratory by degrading a high-energy proton beam, producing a high-fidelity test environment. We use this test environment to dramatically simplify rate prediction for proton direct ionization effects, allowing the work to be done at high-energy proton facilities, on encapsulated parts, without knowledge of the IC design, and with little or no computer simulations required. Proton direct ionization (PDI) is predicted to significantly contribute to the total error rate under the conditions investigated. Scaling effects are discussed using data from 65-nm, 45-nm, and 32-nm SOI SRAMs. These data also show that grazing-angle protons will dominate the PDI-induced error rate due to their higher effective LET, so PDI hardness assurance methods must account for angular effects to be conservative. As a result, we show that this angular dependence can be exploited to quickly assess whether an IC is susceptible to PDI.

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TYPE Journal Article YEAR 2014
DOIOSTI

Progress report of Sandia National Laboratories (SNL) contribu- tion to IAEA CRP F11016 on ?Utilization of ion accelerators for studying and modeling of radiation induced defects in semicon- ductors and insulators? 3rd RCM

Vizkelethy, Gyorgy V.

This report presents the results of Sandia National Laboratories’ (SNL) contribution to IAEA CRP F11016 as mostly raw data. The goal of this CRP is to study the effects of radiation on semiconductors and insulators with the emphasis on the effect of displacement damage due to MeV energy ions on the performance of semiconductor detectors and microelectronic devices. SNL is tasked with performing electrical characterization, irradiation, and IBIC, DLTS, C-­V measurements on devices used in the CRP, as well as calculating damage and ionization profiles for modeling.

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TYPE Other Report YEAR 2014
DOIOSTI
Results 101–125 of 175
Results 101–125 of 175