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Title: Anomalous diffusion of Au in mega-electron-volt Au implanted SiO{sub 2}/Si(100)

Abstract

Thermal annealing induced redistribution behavior of Au (3 MeV, 6.0x10{sup 15} ions cm{sup -2}), implanted into SiO{sub 2}/Si(100) substrates, has been investigated using Rutherford backscattering spectrometry and cross-sectional transmission electron microscopy (XTEM). Sequential annealing in the temperature range of 550-750 degree sign C has been found to result in rejection of Au atoms from Si toward the SiO{sub 2}/Si interface. Above 750 degree sign C a significant fraction of the implanted Au atoms has been found to back diffuse into deeper regions, well below the projected range R{sub p} of Au. Direct annealing of a sample at 850 degree sign C also shows a similar anomalous diffusion of Au into deeper regions, well below R{sub p}. However, direct annealing at 1050 degree sign C has been found to result in an enhanced accumulation of Au at a deeper layer. XTEM micrographs for the same sample show the presence of Au-rich nanoparticles and dislocations, decorated with Au-rich nanoparticles in this region. Trails of Au-Si liquid nanodroplets along with dislocations extending into this region have also been observed. The observed enhanced accumulation of Au in the deeper layer has been explained as due to efficient gettering of diffusing Au atoms at dislocationsmore » in this region, together with the migration of Au-Si liquid nanodroplets into it.« less

Authors:
; ; ; ; ;  [1]
  1. Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India)
Publication Date:
OSTI Identifier:
20982759
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2715747; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; DIFFUSION; DISLOCATIONS; GETTERING; GOLD; LAYERS; LIQUIDS; MEV RANGE 01-10; NANOSTRUCTURES; PARTICLES; RUTHERFORD BACKSCATTERING SPECTROSCOPY; SILICON OXIDES; SUBSTRATES; TEMPERATURE RANGE 0400-1000 K; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Mohapatra, S., Ghatak, J., Joseph, B., Lenka, H. P., Kuiri, P. K., and Mahapatra, D. P.. Anomalous diffusion of Au in mega-electron-volt Au implanted SiO{sub 2}/Si(100). United States: N. p., 2007. Web. doi:10.1063/1.2715747.
Mohapatra, S., Ghatak, J., Joseph, B., Lenka, H. P., Kuiri, P. K., & Mahapatra, D. P.. Anomalous diffusion of Au in mega-electron-volt Au implanted SiO{sub 2}/Si(100). United States. doi:10.1063/1.2715747.
Mohapatra, S., Ghatak, J., Joseph, B., Lenka, H. P., Kuiri, P. K., and Mahapatra, D. P.. Thu . "Anomalous diffusion of Au in mega-electron-volt Au implanted SiO{sub 2}/Si(100)". United States. doi:10.1063/1.2715747.
@article{osti_20982759,
title = {Anomalous diffusion of Au in mega-electron-volt Au implanted SiO{sub 2}/Si(100)},
author = {Mohapatra, S. and Ghatak, J. and Joseph, B. and Lenka, H. P. and Kuiri, P. K. and Mahapatra, D. P.},
abstractNote = {Thermal annealing induced redistribution behavior of Au (3 MeV, 6.0x10{sup 15} ions cm{sup -2}), implanted into SiO{sub 2}/Si(100) substrates, has been investigated using Rutherford backscattering spectrometry and cross-sectional transmission electron microscopy (XTEM). Sequential annealing in the temperature range of 550-750 degree sign C has been found to result in rejection of Au atoms from Si toward the SiO{sub 2}/Si interface. Above 750 degree sign C a significant fraction of the implanted Au atoms has been found to back diffuse into deeper regions, well below the projected range R{sub p} of Au. Direct annealing of a sample at 850 degree sign C also shows a similar anomalous diffusion of Au into deeper regions, well below R{sub p}. However, direct annealing at 1050 degree sign C has been found to result in an enhanced accumulation of Au at a deeper layer. XTEM micrographs for the same sample show the presence of Au-rich nanoparticles and dislocations, decorated with Au-rich nanoparticles in this region. Trails of Au-Si liquid nanodroplets along with dislocations extending into this region have also been observed. The observed enhanced accumulation of Au in the deeper layer has been explained as due to efficient gettering of diffusing Au atoms at dislocations in this region, together with the migration of Au-Si liquid nanodroplets into it.},
doi = {10.1063/1.2715747},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
  • In this article, ballistic electron emission microscopy (BEEM) induced modifications on Au/Si and Au/SiO{sub 2}/Si contacts are presented. BEEM current can be locally enhanced or reduced in a controlled manner. These observations are attributed to tip induced modifications on the gold surface. According to Au thickness, x-ray reflectivity experiments show different surface evolutions correlated to the size variations of the modifications introduced as a function of time. {copyright} 2001 American Institute of Physics.
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