title: Atomic scale analysis of planar defects in polycrystalline diamond.
abstract: Planar defects in a polycrystalline diamond film were studied by high-resolution transmission electron microscopy (HRTEM) and high-resolution scanning transmission electron microscopy (STEM). In both modes, sub-Angstrom resolution was achieved by making use of two aberration-corrected systems; a TEM and a STEM C(s)-corrected microscope, each operated at 300 kV. For the first time, diamond in (110) zone-axis orientation was imaged in STEM mode at a resolution that allows for resolving the atomic dumbbells of carbon at a projected interatomic distance of 89 pm. Twin boundaries that show approximately the sigma3 CSL structure reveal at sub-Angstrom resolution imperfections; that is, local distortions, which break the symmetry of the ideal sigma3 type twin boundary, are likely present. In addition to these imperfect twin boundaries, voids on the atomic level were observed. It is proposed that both local distortions and small voids enhance the mechanical toughness of the film by locally increasing the critical stress intensity factor.
authors.affiliation: FEI Electron Optics, PO Box 80066, 5600 KA Eindhoven, The Netherlands. rolf.erni@ua.ac.be
authors.forename: Rolf
authors.initials: R
authors.lastname: Erni
authors.forename: Bert
authors.initials: B
authors.lastname: Freitag
authors.forename: Peter
authors.initials: P
authors.lastname: Hartel
authors.forename: Heiko
authors.initials: H
authors.lastname: Müller
authors.forename: Peter
authors.initials: P
authors.lastname: Tiemeijer
authors.forename: Michiel
authors.initials: M
authors.lastname: van der Stam
authors.forename: Mike
authors.initials: M
authors.lastname: Stekelenburg
authors.forename: Dominique
authors.initials: D
authors.lastname: Hubert
authors.forename: Petra
authors.initials: P
authors.lastname: Specht
authors.forename: Vincente
authors.initials: V
authors.lastname: Garibay-Febles