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Title: Interfacial role in room-temperature diffusion of Au into Si substrates

Abstract

X-ray reflectivity is used in tracking the diffusion of Au into Si(001) substrates with time at room temperature. It has been observed that the diffusion of Au into Si substrates strongly depends on the initial pretreatment conditions of Si surface. In particular, there is very little diffusion for the untreated Si surface, while the Si surface pretreated with HF seems to be prone to strong diffusion and the surface further pretreated with Br shows diffusion in between. Such different diffusion and apparent non-Fickian-type time dependence in the diffusion can be quantitatively explained by Fickian diffusion of Au through changing unblocked interfacial layer. The growth of the blocking (oxide) layer with time essentially prevents further diffusion through those areas, and the growth of that layer is directly related to the surface stability due to the surface pretreatment and/or passivation conditions, which gives a control in the formation of diffusion-induced Au-Si nanolayer of different widths and compositions. The morphology and evolution of the top surface, mapped with atomic force microscopy and scanning electron microscopy, further helped to verify and understand such differences.

Authors:
;  [1]
  1. Surface Physics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)
Publication Date:
OSTI Identifier:
21045881
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 20; Other Information: DOI: 10.1103/PhysRevB.75.205411; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; ATOMIC FORCE MICROSCOPY; CHANNELING; DIFFUSION; GOLD; HYDROFLUORIC ACID; LAYERS; MORPHOLOGY; OXIDES; PASSIVATION; REFLECTIVITY; SCANNING ELECTRON MICROSCOPY; SILICON; SUBSTRATES; SURFACES; TEMPERATURE RANGE 0273-0400 K; TIME DEPENDENCE; X RADIATION

Citation Formats

Bal, J. K., and Hazra, S.. Interfacial role in room-temperature diffusion of Au into Si substrates. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.205411.
Bal, J. K., & Hazra, S.. Interfacial role in room-temperature diffusion of Au into Si substrates. United States. doi:10.1103/PHYSREVB.75.205411.
Bal, J. K., and Hazra, S.. Tue . "Interfacial role in room-temperature diffusion of Au into Si substrates". United States. doi:10.1103/PHYSREVB.75.205411.
@article{osti_21045881,
title = {Interfacial role in room-temperature diffusion of Au into Si substrates},
author = {Bal, J. K. and Hazra, S.},
abstractNote = {X-ray reflectivity is used in tracking the diffusion of Au into Si(001) substrates with time at room temperature. It has been observed that the diffusion of Au into Si substrates strongly depends on the initial pretreatment conditions of Si surface. In particular, there is very little diffusion for the untreated Si surface, while the Si surface pretreated with HF seems to be prone to strong diffusion and the surface further pretreated with Br shows diffusion in between. Such different diffusion and apparent non-Fickian-type time dependence in the diffusion can be quantitatively explained by Fickian diffusion of Au through changing unblocked interfacial layer. The growth of the blocking (oxide) layer with time essentially prevents further diffusion through those areas, and the growth of that layer is directly related to the surface stability due to the surface pretreatment and/or passivation conditions, which gives a control in the formation of diffusion-induced Au-Si nanolayer of different widths and compositions. The morphology and evolution of the top surface, mapped with atomic force microscopy and scanning electron microscopy, further helped to verify and understand such differences.},
doi = {10.1103/PHYSREVB.75.205411},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 20,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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