Accession Number : ADA255862


Title :   Twin Quintuplets in CVD Diamond


Descriptive Note : Interim rept.


Corporate Author : NATIONAL INST OF STANDARDS AND TECHNOLOGY GAITHERSBURG MD CERAMICS DIV


Personal Author(s) : Shechtman, D ; Feldman, A ; Hutchison, J L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a255862.pdf


Report Date : 26 Aug 1992


Pagination or Media Count : 12


Abstract : The atomic structure of twin quintuplets in a chemical vapor deposited (CVD) diamond film was investigated by high resolution transmission electron microscopy (HRTEM). We conclude that the twin quintuplets have two main morphologies. The first consists of four Sigma = 3 twin boundaries and one Sigma = 81 twin boundary. The Sigma = 81 twin boundary contains the dislocations needed to accommodate a 7.35 deg misfit angle between a set of (111) planes on opposite sides of the boundary. In the second case, the 7.35 deg misfit angle is accommodated by two or more grain boundaries that are tilted slightly more than the 70.53 deg tilt of a Sigma = 3 boundary. These grain boundaries and the conventional diamond lattice twin boundaries are the only types of boundaries that we have observed in CVD diamond.


Descriptors :   *CHEMICAL VAPOR DEPOSITION , *DIAMOND FILMS , ANGLES , HIGH RESOLUTION , ELECTRONS , DISLOCATIONS , TILT , TRANSMISSION ELECTRON MICROSCOPY , ATOMIC STRUCTURE , GRAIN BOUNDARIES , DIFFRACTION , DEFECTS(MATERIALS) , BOUNDARIES , STRUCTURES


Subject Categories : Electrical and Electronic Equipment
      Crystallography
      Coatings, Colorants and Finishes


Distribution Statement : APPROVED FOR PUBLIC RELEASE