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Title: Microstructure and Stress Aspects of Electromigration Modeling

Abstract

The modifications and extensions of standard continuum models used for a description of material transport due to electromigration with models for the copper microstucture are studied. Copper grain boundaries and interfaces are modeled as a network of high diffusivity paths. Additionally, grain boundaries act as sites of vacancy recombination. The connection between mechanical stress and material transport is established for the case of strain build up induced by local vacancy dynamics and the anisotropy of the diffusivity tensor caused by these strains. High diffusivity paths are set on the surfaces of polyhedral domains representing distintcive grains. These polyhedral domains are connected by diffusive, electrical, and mechanical interface models. For a numerical solution a three-dimensional finite element method is used.

Authors:
; ;  [1]; ;  [2]
  1. Institute for Microelectronics, TU Vienna, Gusshausstrasse 27-29, A-1040 Vienna (Austria)
  2. Christian Doppler Laboratory for TCAD in Microelectronics at the Institute for Microelectronics, TU Vienna (Austria)
Publication Date:
OSTI Identifier:
20798186
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 817; Journal Issue: 1; Conference: 8. international workshop on stress-induced phenomena in metallization, Dresden (Germany), 12-14 Sep 2005; Other Information: DOI: 10.1063/1.2173558; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; ANISOTROPY; COPPER; DIFFUSION; ELECTROPHORESIS; FINITE ELEMENT METHOD; GRAIN BOUNDARIES; INTEGRATED CIRCUITS; INTERFACES; RECOMBINATION; SIMULATION; STRAINS; STRESSES; SURFACES; TENSORS; VACANCIES

Citation Formats

Ceric, H., Hollauer, Ch., Selberherr, S., Heinzl, R., and Grasser, T.. Microstructure and Stress Aspects of Electromigration Modeling. United States: N. p., 2006. Web. doi:10.1063/1.2173558.
Ceric, H., Hollauer, Ch., Selberherr, S., Heinzl, R., & Grasser, T.. Microstructure and Stress Aspects of Electromigration Modeling. United States. doi:10.1063/1.2173558.
Ceric, H., Hollauer, Ch., Selberherr, S., Heinzl, R., and Grasser, T.. Tue . "Microstructure and Stress Aspects of Electromigration Modeling". United States. doi:10.1063/1.2173558.
@article{osti_20798186,
title = {Microstructure and Stress Aspects of Electromigration Modeling},
author = {Ceric, H. and Hollauer, Ch. and Selberherr, S. and Heinzl, R. and Grasser, T.},
abstractNote = {The modifications and extensions of standard continuum models used for a description of material transport due to electromigration with models for the copper microstucture are studied. Copper grain boundaries and interfaces are modeled as a network of high diffusivity paths. Additionally, grain boundaries act as sites of vacancy recombination. The connection between mechanical stress and material transport is established for the case of strain build up induced by local vacancy dynamics and the anisotropy of the diffusivity tensor caused by these strains. High diffusivity paths are set on the surfaces of polyhedral domains representing distintcive grains. These polyhedral domains are connected by diffusive, electrical, and mechanical interface models. For a numerical solution a three-dimensional finite element method is used.},
doi = {10.1063/1.2173558},
journal = {AIP Conference Proceedings},
number = 1,
volume = 817,
place = {United States},
year = {Tue Feb 07 00:00:00 EST 2006},
month = {Tue Feb 07 00:00:00 EST 2006}
}
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