Oxygen-Atom Defects In 6H Silicon Carbide Implanted Using 24- MeV O{sup 3+} Ions Measured Using Three-Dimensional Positron Annihilation Spectroscopy System (3DPASS)

Journal Article · Wed Jun 01 00:00:00 EDT 2011 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3586141· OSTI ID:21513398

Williams, Christopher S; Petrosky, James C; Burggraf, Larry W ^[1]; Duan, Xiaofeng F ^[2]

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1. Air Force Institute of Technology, AFIT/ENP, 2950 Hobson Way, Wright-Patterson Air Force Base, OH 45433 (United States)
2. Air Force Research Laboratory's (AFRL) Department of Defense Supercomputing Resource Center (DSRC), Wright-Patterson Air Force Base, OH 45433 (United States)

Three dimensional electron-positron (e{sup -}-e{sup +}) momentum distributions were measured for single crystal 6H silicon carbide (SiC); both virgin and having implanted oxygen-atom defects. 6H SiC samples were irradiated by 24- MeV O{sup 3+} ions at 20 particle-nanoamps at the Sandia National Laboratory's Ion Beam Facility. O{sup 3+} ions were implanted 10.8 {mu}m deep normal to the (0001) face of one side of the SiC samples. During positron annihilation measurements, the opposite face of the 254.0-{mu}m thick SiC samples was exposed to positrons from a {sup 22}Na source. This technique reduced the influence on the momentum measurements of vacancy-type defects resulting from knock-on damage by the O{sup 3+} ions. A three-dimensional positron annihilation spectroscopy system (3DPASS) was used to measure e{sup -}-e{sup +} momentum distributions for virgin and irradiated 6H SiC crystal both before and following annealing. 3DPASS simultaneously measures coincident Doppler-broadening (DBAR) and angular correlation of annihilation radiation (ACAR) spectra. DBAR ratio plots and 2D ACAR spectra are presented. Changes in the momentum anisotropies relative to crystal orientation observed in 2D ACAR spectra for annealed O-implanted SiC agree with the local structure of defect distortion predicted using Surface Integrated Molecular Orbital/Molecular Mechanics (SIMOMM). Oxygen atoms insert between Si and C atoms increasing their separation by 0.9 A forming a Si-O-C bond angle of {approx}150 deg.

• OSTI ID: 21513398
• Journal Information: AIP Conference Proceedings, Vol. 1336, Issue 1; Conference: CAARI 2010: 21. International Conference on the Application of Accelerators in Research and Industry, Fort Worth, TX (United States), 8-13 Aug 2010; Other Information: DOI: 10.1063/1.3586141; (c) 2011 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANGULAR CORRELATION
ANISOTROPY
ANNEALING
ANNIHILATION
CRYSTAL DEFECTS
DOPPLER BROADENING
ELECTRON-POSITRON INTERACTIONS
ION IMPLANTATION
ION SOURCES
MEV RANGE 10-100
MOLECULAR ORBITAL METHOD
MONOCRYSTALS
OXYGEN IONS
PHYSICAL RADIATION EFFECTS
SANDIA NATIONAL LABORATORIES
SILICON CARBIDES
SODIUM 22
SPECTRA
THREE-DIMENSIONAL CALCULATIONS
VACANCIES
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CALCULATION METHODS
CARBIDES
CARBON COMPOUNDS
CHARGED PARTICLES
CORRELATIONS
CRYSTAL STRUCTURE
CRYSTALS
ENERGY RANGE
HEAT TREATMENTS
INTERACTIONS
IONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LEPTON-LEPTON INTERACTIONS
LIGHT NUCLEI
LINE BROADENING
MEV RANGE
NANOSECONDS LIVING RADIOISOTOPES
NATIONAL ORGANIZATIONS
NUCLEI
ODD-ODD NUCLEI
PARTICLE INTERACTIONS
POINT DEFECTS
RADIATION EFFECTS
RADIOISOTOPES
SILICON COMPOUNDS
SODIUM ISOTOPES
US DOE
US ORGANIZATIONS
YEARS LIVING RADIOISOTOPES