Modification of SRIM-calculated dose and injected ion profiles due to sputtering, injected ion buildup and void swelling

Abstract

In radiation effects on materials utilizing self-ion irradiations, it is necessary to calculate the local displacement damage level and ion injection profile because of the short distance that self-ions travel in a material and because of the strong variation of displacement rate with depth in a specimen. The most frequently used tool for this is the software package called Stopping and Range of Ions in Matter (SRIM). A SRIM-calculated depth-dependent dose level is usually determined under the implicit assumption that the target does not undergo any significant changes in volume during the process, in particular SRIM ignores the effect of sputtering, injected ions, and void swelling on the redistribution of the dose and injected ion profiles. This approach become increasingly invalid as the ion fluence reaches ever higher levels, especially for low energy ion irradiations. The original surface is not maintained due to sputterinduced erosion, while within the irradiated region of the specimen, injected ions are adding material, and if void swelling is occurring, it is creating empty space. An iterative mathematical treatment of SRIM outputs to produce corrected dose and injected ion profiles based on these phenomenon and without regard to diffusion is presented along with examples of differences between SRIM-calculated values and corrected values over a range of typical ion energies. The intent is to provide the reader with a convenient tool for more accurately calculating dose and injected ion profiles for heavy-ion irradiations.

Inhibition of stress corrosion cracking in 304 stainless steel through titanium ion implantation

“…The SRIM, as the standard program of Monte Carlo implant damage, was used to predict the production of damage and the depth of the implantation layer [24]. The SRIM, which were used to simulate the displacement per atom (dpa) inducing by neutron, includes inputs, such as types, energies, initial positions and the direction cosines of the Primary Knock-on Atoms (PKAs) [25]. The binding energy is replaced by sublimation heat during the SRIM simulation mainly owing to the unavailability of binding energy on the surface atoms of 304 stainless steel.…”

Impact of variable energy hydrogen ions on structural and mechanical properties of Zircaloy-4

“…After irradiation, the specimens were taken out of the chamber for various characterizations. The penetration depth of H + in Zircaloy-4 was calculated using SRIM software-2013 [19].…”

“…The clear understanding of H + energy variation effects in Zircaloy-4 alloy is still lacking. Since, the energy of incoming particle plays a pivotal role in producing radiation damage inside the nuclear materials [18,19], therefore study of variable energy H + interaction with Zircaloy-4 is of major importance. In this work, effects of changing H + energy on structural, morphological and mechanical properties of Zircaloy-4 were investigated at room temperature while keeping the dose constant.…”

Multiple ion beam irradiation for the study of radiation damage in materials

“…Based on the relative values of the sputtering yield for each specie, the additional sputtering from the light ion beams can be considered negligible until reaching the hundreds to thousands of appm gas/dpa ratio where the fluxes of the light ion species become orders of magnitude larger than the flux of heavy ions. A recent paper [43] considered the effects of sputtering from 5 MeV iron ions up to a fluence of 1 Â 10 18 ions/cm 2 , (nominally 400 dpa at an examination depth of 600 nm in iron). These results suggest that the displacement damage and ion implantation curves are not significantly modified up to 400 dpa from the heavy ion irradiations.…”