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

Report Date:

1992-08-26

Pagination or Media Count:

12.0

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.

Subject Categories:

  • Electrical and Electronic Equipment
  • Crystallography
  • Coatings, Colorants and Finishes

Distribution Statement:

APPROVED FOR PUBLIC RELEASE