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Ion Implantation
Published in Robert Doering, Yoshio Nishi, Handbook of Semiconductor Manufacturing Technology, 2017
Michael Ameen, Ivan Berry, Walter Class, Hans-Joachim Gossmann, Leonard Rubin
Electronic stopping results in excited target electronic states that decay without producing atomic displacements. On the other hand, nuclear stopping results from momentum and energy transfer between the projectile and the target atoms, which may result in the generation of energetic knock-on target atoms that may then produce secondary, tertiary, and higher order knock-on displacements. The resulting damage chain, known as a collision cascade, leaves behind a trail of vacant lattice sites along with implanted atoms and displaced target atoms in substitutional and interstitial positions. The collision-induced defects are predominantly produced as vacancy-interstitial pairs known as Frenkel defects, but can interact on the time-scale of the collision cascade (10−11 s) to recombine or agglomerate into more complex defect configurations. In addition, because of the initial momentum of the impinging projectile ions, the centroid of the interstitial distribution lies deeper in the target than the vacancy distribution.
The Interstellar and Interplanetary Medium
Published in Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff, Radiation and Radioactivity on Earth and Beyond, 2020
Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff
The impact of high-energy protons affects a considerable number of atomic nuclei during the collision cascade process in which the proton’s energy degrades. The number of affected nuclides decreases rapidly from 1014 per gram in the first 10-centimeter layer to 1011 nuclides per gram in a 10-centimeter layer which is located at a depth of 5 meters. Each affected nucleus is responsible for radiation damage in the surrounding material; this may involve displacement of atoms and the appearance of vacant lattice sites, or a large local heating effect (hundreds of degrees kelvin) within a small volume (of the order of a cubic micrometer).
Synthesis and modification of ZnO thin films by energetic ion beams
Published in Radiation Effects and Defects in Solids, 2021
Richa Krishna, Dinesh Chandra Agarwal, Devesh Kumar Avasthi
When an energetic ion incident on a material travels through the matter, it loses its energy due to collisions with atoms and finally stops. The process of losing energy is dominantly governed by elastic collisions in low-energy regime (typically up to ∼10 keV/amu), referred to as nuclear energy loss (Sn). But, the inelastic collision dominates in high-energy regime (typically of energies of ∼1 MeV/amu and beyond), referred to as electronic energy loss (Se). In the Se-dominant regime, the ion energies are so high that the orbital electron velocity of ion is comparable to or larger than the Bohr electron velocity. The values of Se, Sn, range, straggling and number of vacancies created per ion can be estimated by TRIM or SRIM computer codes. The values of Se and Sn at different energies of Si ions in ZnO are plotted in Figure 1. For the ion energies ranging from few keVs to few MeV, the energetic ion hits the atom in materials and partially transfers its energy to the atom. The displaced or recoiled atom might have sufficient energy to produce further recoils resulting in a collision cascade. The elastic collisions of incident ion continue until the ion finally stops.