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Title: Charge-state dependence of energy loss of MeV dimers in GaAs(100)

Abstract

Carbon and oxygen dimers with charge states 1+ and 3+ were implanted into GaAs along the [100] direction at an energy of 0.5 MeV/atom. The defect depth profiles are extracted from Rutherford backscattering spectrometry and channeling. The depth profile of carbon is extracted from secondary ion mass spectrometry measurements. The defect density produced by dimer ions is larger than monomer ions. The depth profile of carbon in dimer implanted GaAs is deeper than that of monomer implanted GaAs showing negative molecular effect. The defect depth profile of oxygen dimer implanted GaAs is deeper for 3+ than that for 1+ charge state. This indicates that energy loss of O{sub 2}{sup 3+} is smaller than that of O{sub 2}{sup +}. It is attributed to charge asymmetry and a higher degree of alignment of O{sub 2}{sup 3+} along the [100] axis of GaAs.

Authors:
; ; ; ; ; ; ;  [1]
  1. Materials Science Division, Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India)
Publication Date:
OSTI Identifier:
20787117
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.042902; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ASYMMETRY; ATOMS; CARBON; CHANNELING; CHARGE STATES; CRYSTAL DEFECTS; DIMERS; GALLIUM ARSENIDES; ION IMPLANTATION; MASS SPECTRA; MASS SPECTROSCOPY; MEV RANGE; MOLECULAR IONS; MONOMERS; OXYGEN; RUTHERFORD BACKSCATTERING SPECTROSCOPY; SEMICONDUCTOR MATERIALS

Citation Formats

Sundaravel, B., David, Christopher, Balamurugan, A. K., Rajagopalan, S., Tyagi, A. K., Panigrahi, B. K., Nair, K. G. M., and Viswanathan, B.. Charge-state dependence of energy loss of MeV dimers in GaAs(100). United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Sundaravel, B., David, Christopher, Balamurugan, A. K., Rajagopalan, S., Tyagi, A. K., Panigrahi, B. K., Nair, K. G. M., & Viswanathan, B.. Charge-state dependence of energy loss of MeV dimers in GaAs(100). United States. doi:10.1103/PHYSREVA.73.0.
Sundaravel, B., David, Christopher, Balamurugan, A. K., Rajagopalan, S., Tyagi, A. K., Panigrahi, B. K., Nair, K. G. M., and Viswanathan, B.. Sat . "Charge-state dependence of energy loss of MeV dimers in GaAs(100)". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787117,
title = {Charge-state dependence of energy loss of MeV dimers in GaAs(100)},
author = {Sundaravel, B. and David, Christopher and Balamurugan, A. K. and Rajagopalan, S. and Tyagi, A. K. and Panigrahi, B. K. and Nair, K. G. M. and Viswanathan, B.},
abstractNote = {Carbon and oxygen dimers with charge states 1+ and 3+ were implanted into GaAs along the [100] direction at an energy of 0.5 MeV/atom. The defect depth profiles are extracted from Rutherford backscattering spectrometry and channeling. The depth profile of carbon is extracted from secondary ion mass spectrometry measurements. The defect density produced by dimer ions is larger than monomer ions. The depth profile of carbon in dimer implanted GaAs is deeper than that of monomer implanted GaAs showing negative molecular effect. The defect depth profile of oxygen dimer implanted GaAs is deeper for 3+ than that for 1+ charge state. This indicates that energy loss of O{sub 2}{sup 3+} is smaller than that of O{sub 2}{sup +}. It is attributed to charge asymmetry and a higher degree of alignment of O{sub 2}{sup 3+} along the [100] axis of GaAs.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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