Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10674856 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2011 | 5 Pages |
Abstract
Using molecular dynamics simulations (MD), this contribution compares the interaction of three energetic clusters (Au3, Au400 and C60) with a hybrid surface of crystalline polyethylene (PE) covered by a layer of gold nanoparticles. This model system mimics the situation encountered in metal-assisted secondary ion mass spectrometry. The chosen impact points are representative of the PE surface, the metal particles and the frontier between the metal and the polymer. The simulations show the differences between the impact over the Au nanoparticle and the polymer surface, in terms of projectile penetration, crater formation and sputtering yield of PE and gold species. For C60 and Au3 projectiles, a simple correlation is found between the quantity of energy deposited in the top polymeric layers and the quantity of sputtered polymer material, including all the impact points. The results obtained with Au400 do not fit on this line, indicating that other physical parameters are prevalent. The mechanistic view of the interaction provided by the MD helps explain the differences. In short, while C60 and Au3 quickly break apart, creating energetic recoils and severing many bonds in the surface, Au400, with the largest total momentum by far (â¼10 times larger than the others) and the lowest energy per atom (25Â eV), tends to act and implant in the solid as a single entity, pushing the polymeric material downwards and breaking few bonds in the surface.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
Oscar A. Restrepo, Aneesh Prabhakaran, Arnaud Delcorte,