Hierarchical Structuring of Black Silicon Wafers by Ion-Flow-Stimulated Roughening Transition: Fundamentals and Applications for Photovoltaics.

Ion-flow-stimulated roughening transition is a phenomenon that may prove useful in the hierarchical structuring of nanostructures. In this work, we have investigated theoretically and experimentally the surface texturing of single-crystal and multi-crystalline silicon wafers irradiated using ion-beam flows. In contrast to previous studies, ions had relatively low energies, whereas flow densities were high enough to induce a quasi-liquid state in the upper silicon layers.

Influence of leucite content on slow crack growth of dental porcelains.

Objectives: To determine the stress corrosion susceptibility coefficient, n, of seven dental porcelains (A: Ceramco I; B: Ceramco-II; C: Ceramco-III; D: d.Sign; E: Cerabien; F: Vitadur-Alpha; and G: Ultropaline) after aging in air or artificial saliva, and correlate results with leucite content (LC).

Methods: Bars were fired according to manufacturers' instructions and polished before induction of cracks by a Vickers indenter (19.