Molecular Dynamics simulations of Cu/Ta and Ta/Cu thin film growth

Copper is themetal of choice for modern IC interconnects, but copper diffuses into silicon and drifts on silicon oxide quite rapidly, degrading the device properties. Therefore, diffusion barriers must be used to keep copper from interacting with silicon and silicon oxide. Molecular Dynamics simulat...

Full description

Saved in:
Bibliographic Details
Published inJournal of computer-aided materials design Vol. 10; no. 2; pp. 61 - 74
Main Authors KLAVER, T. P. C, THIJSSE, B. J
Format Journal Article
LanguageEnglish
Published Dordrecht Springer 2003
Subjects
Cross-disciplinary physics: materials science; rheology
Exact sciences and technology
Materials science
Methods of deposition of films and coatings; film growth and epitaxy
Physics
Theory and models of film growth
Misfit dislocations
Metals
simulation
Molecular dynamics method
Roughness
Molecular dynamics
deposition
Surface temperature
Rough surfaces
Thin films
Tantalum
BCC crystals
thin film
Modelling
Copper
Microstructure
Dynamic model
Online AccessGet full text

Cover

More Information
Summary:Copper is themetal of choice for modern IC interconnects, but copper diffuses into silicon and drifts on silicon oxide quite rapidly, degrading the device properties. Therefore, diffusion barriers must be used to keep copper from interacting with silicon and silicon oxide. Molecular Dynamics simulation results of evaporated Cu deposition on bcc Ta substrates are presented. Different substrate orientations, substrate temperatures, and initial surface roughnesses were investigated. We have also simulated the deposition of Ta on flat fcc Cu (111) substrates at different temperatures. Several aspects of the microstructural evolution during deposition are reported. The results are also compared with those obtained earlier for Cu deposition on fl-Ta. A connection mechanism between two different crystal structures, bcc (110) and fcc (111), which is significantly different from the classical misfit dislocation scenario, is reported. Also, mixing behaviour in a thermodynamically immiscible system during atom-by-atom deposition of Ta on fcc Cu (111) is elucidated. Finally, we show results of a Density Functional Theory verification of the accuracy of the Ta-Cu emperical potential. Results and implications are discussed.
Bibliography:ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ISSN:0928-1045
1573-4900
DOI:10.1023/B:JCAD.0000036802.46424.ee