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Title: Thermal evolution of boron irradiation induced defects in predoped Si revealed by positron annihilation experiments

Abstract

The isochronal annealing behavior of high energy (25-72 MeV) boron ion irradiation induced defects in boron-doped silicon is monitored through measurements of positron lifetimes and three distinct defect-evolution stages are identified. The initial boron doping created a defect environment where positrons could sensitively annihilate with the boron electrons, suggesting boron-decorated Si monovacancies as potential trapping sites. The irradiation results in the dissolution of boron from these sites and positrons are then trapped by the empty divacancies of Si. Charge neutralization of divacancies through interaction with boron atoms leads to enhanced positron trapping in the initial stages of isochronal annealing. The divacancies start annealing above 673 K. However, a remarkable defect evolution stage due to the diffusion of the boron atoms beyond their initial depths of penetration is seen above 873 K and it leaves the sample with defects still present even at the highest annealing temperature 1273 K used in this work.

Authors:
; ;  [1];  [2];  [2]
  1. Nuclear and Atomic Physics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)
  2. (India)
Publication Date:
OSTI Identifier:
20979415
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 11; Other Information: DOI: 10.1063/1.2737786; (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; ANNIHILATION; BORON; BORON IONS; CRYSTALS; DISSOLUTION; DOPED MATERIALS; ELECTRONS; EVOLUTION; ION BEAMS; IRRADIATION; LIFETIME; MEV RANGE 10-100; POSITRONS; SEMICONDUCTOR MATERIALS; SILICON; TRAPPING; VACANCIES

Citation Formats

Nambissan, P. M. G., Bhagwat, P. V., Kurup, M. B., Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, and Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005. Thermal evolution of boron irradiation induced defects in predoped Si revealed by positron annihilation experiments. United States: N. p., 2007. Web. doi:10.1063/1.2737786.
Nambissan, P. M. G., Bhagwat, P. V., Kurup, M. B., Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, & Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005. Thermal evolution of boron irradiation induced defects in predoped Si revealed by positron annihilation experiments. United States. doi:10.1063/1.2737786.
Nambissan, P. M. G., Bhagwat, P. V., Kurup, M. B., Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, and Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005. Fri . "Thermal evolution of boron irradiation induced defects in predoped Si revealed by positron annihilation experiments". United States. doi:10.1063/1.2737786.
@article{osti_20979415,
title = {Thermal evolution of boron irradiation induced defects in predoped Si revealed by positron annihilation experiments},
author = {Nambissan, P. M. G. and Bhagwat, P. V. and Kurup, M. B. and Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 and Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005},
abstractNote = {The isochronal annealing behavior of high energy (25-72 MeV) boron ion irradiation induced defects in boron-doped silicon is monitored through measurements of positron lifetimes and three distinct defect-evolution stages are identified. The initial boron doping created a defect environment where positrons could sensitively annihilate with the boron electrons, suggesting boron-decorated Si monovacancies as potential trapping sites. The irradiation results in the dissolution of boron from these sites and positrons are then trapped by the empty divacancies of Si. Charge neutralization of divacancies through interaction with boron atoms leads to enhanced positron trapping in the initial stages of isochronal annealing. The divacancies start annealing above 673 K. However, a remarkable defect evolution stage due to the diffusion of the boron atoms beyond their initial depths of penetration is seen above 873 K and it leaves the sample with defects still present even at the highest annealing temperature 1273 K used in this work.},
doi = {10.1063/1.2737786},
journal = {Journal of Applied Physics},
number = 11,
volume = 101,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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