Nano-scale modification of 2D surface structures exposed to 6keV carbon ions: Experiment and modeling

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 269; no. 6; pp. 582 - 589
• Main Authors: Mutzke, Andreas, Bizyukov, Ivan, Schneider, Ralf, Davis, James
• Format: Journal Article
• Language: English
• Published: 15-03-2011
• Subjects: Exposure; Implantation; Mathematical models; Morphology; Nanomaterials; Nanostructure; Sputtering; Two dimensional
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2011.01.012

In this work, a Si pitch grating with typical lateral dimensions of 200-250nm was exposed to 6keV C+ ions at normal incidence and at an angle of 42A degree both parallel and perpendicular to the grating structure. In contrast to volatile and recycling ions (like Ar+ or H+), non-recycling ions are able to modify the surface not only due to sputtering, but also due to implantation of incident ions and the re-deposition of projectile atoms following sputtering or reflection. The target-projectile combination used in this work is an example of such a system forming a mixed Si-C surface. The interaction between the ion beam and the surface has been studied both experimentally and numerically with the focus on validation of the numerical model of the newly developed SDTrimSP-2D code. SDTrimSP-2D is capable of following the evolution of the Si-C system including ion-surface interactions with 2D micro- and nano-structured surfaces. The SDTrimSP-2D code takes the interdependency of surface morphology, sputtering and implantation into account. The simulated surface morphology has been compared to cross-sections of bombarded Si pitch grating obtained by SEM, revealing good agreement between experiment and simulation. The calculations also provide improved insight into the mechanisms of surface modification by sputtering, implantation and material transport by redeposition.