title: Anomalous impurity segregation and local bonding fluctuation in l-Si.
abstract: Anomalous impurity redistribution after a laser irradiation process in group-IV elements has been reported in numerous papers. In this Letter, we correlate this still unexplained behavior with the peculiar bonding character of the liquid state of group-IV semiconductors. Analyzing the B-Si system in a wide range of experimental conditions we demonstrate that this phenomenon derives from the non-Fickian diffusion transport of B in l-Si. The proposed diffusion model relies on the balance between two impurity states in different bonding configurations: one migrating at higher diffusivity than the other. This microscopic mechanism explains the anomalous B segregation, whereas accurate comparisons between experimental chemical profiles and simulation results validate the model.
authors.affiliation: CNR IMM, Z.I. VIII Strada 5, I -95121 Catania, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Fisicaro
authors.affiliation: Excico 13-21 Quai des Gresillons, 92230 Gennevilliers, France.
authors.forename: K
authors.initials: K
authors.lastname: Huet
authors.affiliation: Excico 13-21 Quai des Gresillons, 92230 Gennevilliers, France.
authors.forename: R
authors.initials: R
authors.lastname: Negru
authors.affiliation: Fraunhofer Institute for Integrated Systems and Device Technology, Schottkystrasse 10, 91058 Erlangen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Hackenberg
authors.affiliation: Fraunhofer Institute for Integrated Systems and Device Technology, Schottkystrasse 10, 91058 Erlangen, Germany and Chair of Electron Devices, University of Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Pichler
authors.affiliation: Probion, 37 Rue de Fontenay, 92220 Bagneux, France.
authors.forename: N
authors.initials: N
authors.lastname: Taleb
authors.affiliation: CNR IMM, Z.I. VIII Strada 5, I -95121 Catania, Italy.
authors.forename: A
authors.initials: A
authors.lastname: La Magna