Grain boundary diffusion in thin films with a bimodal grain boundary structure

A. Makovec, G. Erdélyi, D. Beke

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Diffusion through different grain boundaries (GBs) in thin films is analyzed by solving the diffusion equations numerically. Supposing a bimodal grain structure, i.e. boundaries with low and high diffusivities, the thin film diffusion problem is solved using the following boundary conditions: one surface is maintained at unit concentration, at the back surface zero flux or fast surface diffusion and the formation of a secondary diffusion source is supposed. In the case of a C kinetic regime, the contributions of the fast and slow boundaries can be separated: the appearance time of the secondary diffusion source is determined by the high diffusivity boundaries, on the other hand, the diffusion broadening of the region in which the grain boundaries are saturated is controlled by the slow GBs. Similarly, the out-diffusion from the secondary diffusion source is also controlled by the slow GBs. From the time evolution of the concentration profiles measured experimentally in the Ta/Co/Si system, Si diffusivities are determined by fitting our numerical solutions. Our results underline the importance of the fitting procedure proposed in this article, i.e. the fitting of the central part of the film can be free of errors due to instrumental broadening around the interfaces.

Original languageEnglish
Pages (from-to)2362-2367
Number of pages6
JournalThin Solid Films
Volume520
Issue number6
DOIs
Publication statusPublished - Jan 1 2012

Fingerprint

Grain boundaries
grain boundaries
Thin films
thin films
diffusivity
surface diffusion
Surface diffusion
Crystal microstructure
boundary conditions
kinetics
Boundary conditions
profiles
Fluxes
Kinetics

Keywords

  • Bimodal structure
  • Grain boundary diffusion
  • Secondary Neutral Mass Spectrometry
  • Triple junctions
  • Type C regime

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Materials Chemistry
  • Metals and Alloys
  • Surfaces, Coatings and Films
  • Surfaces and Interfaces

Cite this

Grain boundary diffusion in thin films with a bimodal grain boundary structure. / Makovec, A.; Erdélyi, G.; Beke, D.

In: Thin Solid Films, Vol. 520, No. 6, 01.01.2012, p. 2362-2367.

Research output: Contribution to journalArticle

Makovec, A. ; Erdélyi, G. ; Beke, D. / Grain boundary diffusion in thin films with a bimodal grain boundary structure. In: Thin Solid Films. 2012 ; Vol. 520, No. 6. pp. 2362-2367.
@article{01bd2837a9b04375a3bce316fe550888,
title = "Grain boundary diffusion in thin films with a bimodal grain boundary structure",
abstract = "Diffusion through different grain boundaries (GBs) in thin films is analyzed by solving the diffusion equations numerically. Supposing a bimodal grain structure, i.e. boundaries with low and high diffusivities, the thin film diffusion problem is solved using the following boundary conditions: one surface is maintained at unit concentration, at the back surface zero flux or fast surface diffusion and the formation of a secondary diffusion source is supposed. In the case of a C kinetic regime, the contributions of the fast and slow boundaries can be separated: the appearance time of the secondary diffusion source is determined by the high diffusivity boundaries, on the other hand, the diffusion broadening of the region in which the grain boundaries are saturated is controlled by the slow GBs. Similarly, the out-diffusion from the secondary diffusion source is also controlled by the slow GBs. From the time evolution of the concentration profiles measured experimentally in the Ta/Co/Si system, Si diffusivities are determined by fitting our numerical solutions. Our results underline the importance of the fitting procedure proposed in this article, i.e. the fitting of the central part of the film can be free of errors due to instrumental broadening around the interfaces.",
keywords = "Bimodal structure, Grain boundary diffusion, Secondary Neutral Mass Spectrometry, Triple junctions, Type C regime",
author = "A. Makovec and G. Erd{\'e}lyi and D. Beke",
year = "2012",
month = "1",
day = "1",
doi = "10.1016/j.tsf.2011.11.013",
language = "English",
volume = "520",
pages = "2362--2367",
journal = "Thin Solid Films",
issn = "0040-6090",
publisher = "Elsevier",
number = "6",

}

TY - JOUR

T1 - Grain boundary diffusion in thin films with a bimodal grain boundary structure

AU - Makovec, A.

AU - Erdélyi, G.

AU - Beke, D.

PY - 2012/1/1

Y1 - 2012/1/1

N2 - Diffusion through different grain boundaries (GBs) in thin films is analyzed by solving the diffusion equations numerically. Supposing a bimodal grain structure, i.e. boundaries with low and high diffusivities, the thin film diffusion problem is solved using the following boundary conditions: one surface is maintained at unit concentration, at the back surface zero flux or fast surface diffusion and the formation of a secondary diffusion source is supposed. In the case of a C kinetic regime, the contributions of the fast and slow boundaries can be separated: the appearance time of the secondary diffusion source is determined by the high diffusivity boundaries, on the other hand, the diffusion broadening of the region in which the grain boundaries are saturated is controlled by the slow GBs. Similarly, the out-diffusion from the secondary diffusion source is also controlled by the slow GBs. From the time evolution of the concentration profiles measured experimentally in the Ta/Co/Si system, Si diffusivities are determined by fitting our numerical solutions. Our results underline the importance of the fitting procedure proposed in this article, i.e. the fitting of the central part of the film can be free of errors due to instrumental broadening around the interfaces.

AB - Diffusion through different grain boundaries (GBs) in thin films is analyzed by solving the diffusion equations numerically. Supposing a bimodal grain structure, i.e. boundaries with low and high diffusivities, the thin film diffusion problem is solved using the following boundary conditions: one surface is maintained at unit concentration, at the back surface zero flux or fast surface diffusion and the formation of a secondary diffusion source is supposed. In the case of a C kinetic regime, the contributions of the fast and slow boundaries can be separated: the appearance time of the secondary diffusion source is determined by the high diffusivity boundaries, on the other hand, the diffusion broadening of the region in which the grain boundaries are saturated is controlled by the slow GBs. Similarly, the out-diffusion from the secondary diffusion source is also controlled by the slow GBs. From the time evolution of the concentration profiles measured experimentally in the Ta/Co/Si system, Si diffusivities are determined by fitting our numerical solutions. Our results underline the importance of the fitting procedure proposed in this article, i.e. the fitting of the central part of the film can be free of errors due to instrumental broadening around the interfaces.

KW - Bimodal structure

KW - Grain boundary diffusion

KW - Secondary Neutral Mass Spectrometry

KW - Triple junctions

KW - Type C regime

UR - http://www.scopus.com/inward/record.url?scp=84855955785&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84855955785&partnerID=8YFLogxK

U2 - 10.1016/j.tsf.2011.11.013

DO - 10.1016/j.tsf.2011.11.013

M3 - Article

VL - 520

SP - 2362

EP - 2367

JO - Thin Solid Films

JF - Thin Solid Films

SN - 0040-6090

IS - 6

ER -