Defect and dopant depth profiles in boron-implanted silicon studied with channeling and nuclear reaction analysis

ABSTRACTNi foils and samples consisting of bilayers of Ni or Fe on Al, Ti or Si were implanted at room temperature with 15N+ ions to fluences of around 1×l017 N/cm2. The concentration depth profiles of 15N were determined with nuclear reaction analysis before and after vacuum annealing. It was found that the penetrability for N atoms of the surface and the solid/solid interface plays an important role in the N redistribution during implantation or annealing. The formation of a nitride layer or nitride clusters in Ni and Fe was deduced. Parameters for N migration determined for the metals under investigation are discussed in terms of models.

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The synergies between displacement damage creation and hydrogen presence: the effect of D ion energy and flux

Physica Scripta ◽

10.1088/1402-4896/ac4860 ◽

2022 ◽

Author(s):

Sabina Markelj ◽

Matic Pečovnik ◽

Thomas Schwarz-Selinger ◽

Mitja Kelemen

Keyword(s):

Nuclear Reaction ◽

Thermal Desorption ◽

Rate Equation ◽

Irradiation Time ◽

Thermal Desorption Spectroscopy ◽

Nuclear Reaction Analysis ◽

Displacement Damage ◽

Ion Energy ◽

Depth Profiles ◽

Different Temperatures

Abstract In this work the synergism between displacement damage creation and presence of hydrogen isotopes was studied. Tungsten samples were irradiated by 10.8 MeV W ions with or without the presence of D ions with two different energies of 300 eV/D and 1000 eV/D and different temperatures. In order to compare the results obtained with different exposure parameters the samples were afterwards additionally exposed to D ions at 450 K to populate the created defects. By increasing the W irradiation time, ion flux and energy, the increase of D concentration and D retention was observed as measured by nuclear reaction analysis and thermal desorption spectroscopy. By fitting the D depth profiles and D desorption spectra by the rate equation code MHIMS-R we could see that additional fill-levels were populated with higher flux and ion energy which ends up in higher final D concentration and retention as compared to experiments with lower D flux and energy.

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Helium Migration Mechanisms in Polycrystalline Uranium Dioxide

MRS Proceedings ◽

10.1557/proc-985-0985-nn05-02 ◽

2006 ◽

Vol 985 ◽

Cited By ~ 1

Author(s):

Guillaume Martin ◽

Pierre Desgardin ◽

Philippe Garcia ◽

Thierry Sauvage ◽

Gaëlle Carlot ◽

...

Keyword(s):

Grain Boundaries ◽

Nuclear Reaction ◽

Uranium Dioxide ◽

Nuclear Reaction Analysis ◽

Annealing Stage ◽

Depth Profiles ◽

Release Mechanisms ◽

Helium Diffusion

AbstractThis study aims at identifying the release mechanisms of helium in uranium dioxide. Two sets of polycrystalline UO2 sintered samples presenting different microstructures were implanted with 3He ions at concentrations in the region of 0.1 at.%. Changes in helium concentrations were monitored using two Nuclear Reaction Analysis (NRA) techniques based on the 3He(d,α)1H reaction. 3He release is measured in-situ during sample annealing at temperatures ranging between 700°C and 1000°C. Accurate helium depth profiles are generated after each annealing stage. Results that provide data for further understanding helium release mechanisms are discussed. It is found that helium diffusion appears to be enhanced above 900°C in the vicinity of grain boundaries possibly as a result of the presence of defects.

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