Determination of recombination radius in Si for binary collision approximation codes

Journal Article · Fri Sep 11 00:00:00 EDT 2015 · Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms

DOI:https://doi.org/10.1016/j.nimb.2015.08.088· OSTI ID:1237661

Vizkelethy, Gyorgy ^[1]; Foiles, Stephen M. ^[1]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

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.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000
• OSTI ID: 1237661
• Alternate ID(s): OSTI ID: 22569050
• Report Number(s): SAND--2015-5277J; PII: S0168583X15008241
• Journal Information: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Journal Name: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms Journal Issue: 1 Vol. 5; ISSN 0168-583X
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
binary collision approximation
displacement threshold energy
molecular dynamics
recombination radius