Strain-Induced Asymmetric Line Segregation at Faceted Si Grain Boundaries

Abstract

The unique combination of atomic-scale composition measurements, employing atom probe tomography, atomic structure determination with picometer resolution by aberration-corrected scanning transmission electron microscopy, and atomistic simulations reveals site-specific linear segregation features at grain boundary facet junctions. More specific, an asymmetric line segregation along one particular type of facet junction core, instead of a homogeneous decoration of the facet planes, is observed. Molecular-statics calculations show that this segregation pattern is a consequence of the interplay between the asymmetric core structure and its corresponding local strain state. Our results contrast with the classical view of a homogeneous decoration of the facet planes and evidence a complex segregation patterning.

Interface dominated cooperative nanoprecipitation in interstitial alloys

“…3 . As also recently shown by Liebscher et al 32 , the existence of misfit strain can induce solute segregation to interfaces. However, our calculations show that the difference in the chemical potential of C between ferrite and cementite is already ~0.9 eV.…”

Segregation-Induced Nanofaceting Transition at an Asymmetric Tilt Grain Boundary in Copper

“…Nevertheless, it would be interesting to study effects of segregation to junctions and how they influence the energetics of the systems including the interaction between junctions, which was neglected here. Segregation to facet junctions was for example recently observed at faceted Si [49] and Cu GBs [50].…”

Mg Deficiency in Grain Boundaries of n‐Type Mg3Sb2 Identified by Atom Probe Tomography

“…APT has the capability of chemically characterizing materials in 3D on an atom‐by‐atom basis, which helps to understand the formation of nanostructures in metals and semiconductors. The technique has been applied to detect off‐stoichiometry around the grain boundaries in various semiconductors such as silicon, chalcogenides, filled skutterdites, zintls, oxides, and other systems . The results suggest that the resistance of the grain boundaries in Mg 3 Sb 2 ‐based materials can be attributed to a Mg deficiency that greatly reduces the local free charge carrier concentration.…”