Origins of the change in mechanical strength of silicon/gold nanocomposites during irradiation

AbstractSilicon-based layered nanocomposites, comprised of covalent-metal interfaces, have demonstrated elevated resistance to radiation. The amorphization of the crystalline silicon sublayer during irradiation and/or heating can provide an additional mechanism for accommodating irradiation-induced defects. In this study, we investigated the mechanical strength of irradiated Si-based nanocomposites using atomistic modeling. We first examined dose effects on the defect evolution mechanisms near silicon-gold crystalline and amorphous interfaces. Our simulations reveal the growth of an emergent amorphous interfacial layer with increasing dose, a dominant factor mitigating radiation damage. We then examined the effect of radiation on the mechanical strength of silicon-gold multilayers by constructing yield surfaces. These results demonstrate a rapid onset strength loss with dose. Nearly identical behavior is observed in bulk gold, a phenomenon that can be rooted to the formation of radiation-induced stacking fault tetrahedra which dominate the dislocation emission mechanism during mechanical loading. Taken together, these results advance our understanding of the interaction between radiation-induced point defects and metal-covalent interfaces.

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Electrically Active Defects In Solar Cells Based On Amorphous Silicon/Crystalline Silicon Heterojunction After Irradiation By Heavy Xe Ions

Journal of Electrical Engineering ◽

10.2478/jee-2015-0053 ◽

2015 ◽

Vol 66 (6) ◽

pp. 323-328 ◽

Cited By ~ 3

Author(s):

Ladislav Harmatha ◽

Miroslav Mikolášek ◽

L’ubica Stuchlíková ◽

Arpád Kósa ◽

Milan Žiška ◽

...

Keyword(s):

Amorphous Silicon ◽

Heavy Ions ◽

Deep Level Transient Spectroscopy ◽

Crystalline Silicon ◽

Deep Level ◽

Different Types ◽

Radiation Induced ◽

Transient Spectroscopy ◽

Induced Defects ◽

Hydrogenated Amorphous

Abstract The contribution is focused on the diagnostics of structures with a heterojunction between amorphous and crystalline silicon prepared by HIT (Heterojunction with an Intrinsic Thin layer) technology. The samples were irradiated by Xe ions with energy 167 MeV and doses from 5 × 108 cm−2 to 5 × 1010 cm−2. Radiation defects induced in the bulk of Si and at the hydrogenated amorphous silicon and crystalline silicon (a-Si:H/c-Si) interface were identified by Deep Level Transient Spectroscopy (DLTS). Radiation induced A-centre traps, boron vacancy traps and different types of divacancies with a high value of activation energy were observed. With an increased fluence of heavy ions the nature and density of the radiation induced defects was changed.

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Xenon ion irradiation of superconducting YBa2Cu3O7 thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173595 ◽

1990 ◽

Vol 48 (4) ◽

pp. 92-93

Author(s):

H. Watanabe ◽

B. Kabius ◽

B. Roas ◽

K. Urban

Keyword(s):

Defect Formation ◽

Ion Irradiation ◽

High Resolution Electron Microscopy ◽

Structural Disorder ◽

Flux Lines ◽

Pinning Effect ◽

Magnetic Flux Lines ◽

Resolution Electron ◽

Radiation Induced ◽

Induced Defects

Recently it was reported that the critical current density(Jc) of YBa2Cu2O7, in the presence of magnetic field, is enhanced by ion irradiation. The enhancement is thought to be due to the pinning of the magnetic flux lines by radiation-induced defects or by structural disorder. The aim of the present study was to understand the fundamental mechanisms of the defect formation in association with the pinning effect in YBa2Cu3O7 by means of high-resolution electron microscopy(HRTEM).The YBa2Cu3O7 specimens were prepared by laser ablation in an insitu process. During deposition, a substrate temperature and oxygen atmosphere were kept at about 1073 K and 0.4 mbar, respectively. In this way high quality epitaxially films can be obtained with the caxis parallel to the <100 > SrTiO3 substrate normal. The specimens were irradiated at a temperature of 77 K with 173 MeV Xe ions up to a dose of 3.0 × 1016 m−2.

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