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The Relationship between the Microscopic Properties of Semiconducting Grain Boundaries and their Orientation

Published online by Cambridge University Press:  16 February 2011

Eugen Tarnow ,
Tomas Arias ,
P. D. Bristowe ,
P. Dallot ,
G. P. Francis ,
J. D. Joannopoulos  and
M. C. Payne
Eugen Tarnow
Affiliation:
Xerox Palo Alto Research Center, 3333 Coyote Hill Rd, Palo Alto, CA 94304
Tomas Arias
Affiliation:
Massachusetts Institute of Technology, Dept. of Physics, Cambridge, MA 02139
P. D. Bristowe
Affiliation:
Massachusetts Institute of Technology, Dept. of Physics, Cambridge, MA 02139
P. Dallot
Affiliation:
Massachusetts Institute of Technology, Dept. of Physics, Cambridge, MA 02139
G. P. Francis
Affiliation:
Cavendish Laboratory, Cambridge, CB3 OHE, England
J. D. Joannopoulos
Affiliation:
Massachusetts Institute of Technology, Dept. of Physics, Cambridge, MA 02139
M. C. Payne
Affiliation:
Cavendish Laboratory, Cambridge, CB3 OHE, England
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Abstract

The microscopic structure of a tilt and a twist boundary in germanium are explored using a state-of-the-art total energy calculation. The structure of the tilt boundary (Σ = 5 (310)) is found to be simple as it exhibits a well defined minimum energy structure, consistent with previous experimental and theoretical results on this and other tilt boundaries. The structure of the twist boundary (Σ = 5 (100)), however, is found to be very complex. The boundary bonds are distorted and weak, and their weakness makes the twist boundary exhibit a wealth of local energy minima. The different types of energy minima for the twist boundaries are identified and studied in some detail. We summarize the consequence of the orientation of the two crystal grains upon the microscopic structure of the boundaries, and speculate about future applications.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 193: Symposium Q – Atomic Scale Calculations of Structure in Materials , 1990 , 235
Copyright
Copyright © Materials Research Society 1990

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References

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