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Calculations of the Electronic Structure of Vacancies in a-Si:H

Published online by Cambridge University Press:  01 January 1992

Ariel A. Valladares  and
L. Enrique Sansores
Ariel A. Valladares
Affiliation:
Institute de Investigaciones en Materiales, UNAM, Apartado Postal 70-360, México, D.F., 04510, MEXICO.
L. Enrique Sansores
Affiliation:
Institute de Investigaciones en Materiales, UNAM, Apartado Postal 70-360, México, D.F., 04510, MEXICO.
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Abstract

The electronic structure of random clusters has been used in the literature as representative of the electronic structure of random solids. In this work a calculation of the local density of states (LDOS) and charge density contours for clusters of the type XSi20H28 with X an Si atom, a vacancy or 4 hydrogen atoms, has been carried out. The method used was a pseudopotential SCF Hartree-Fock and the HONDO program. It is found that the generation of a vacancy in the center of the cluster (removal of the central Si atom), introduces p-like states in the energy gap of the LDOS for the region near the center of the cluster. The saturation of the dangling bonds of the vacancy with 4 hydrogen atoms removes the states within the gap. These results are also borne out by the charge density contours, thereby reinforcing the importance of amorphous cluster calculations in the understanding of the electronic structure of amorphous solids.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 291: Symposium O – Materials Theory and Modeling , 1992 , 349
Copyright
Copyright © Materials Research Society 1993

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References

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