Positron studies of defects in ion-implanted SiC

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.54.3084· OSTI ID:286667

Brauer, G; Anwand, W ^[1]; Coleman, P G; Knights, A P ^[2]; Plazaola, F ^[3]; Pacaud, Y; Skorupa, W ^[4]; Stoermer, J; Willutzki, P ^[5]

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1. Arbeitsgruppe Positronen-Annihilations-Spektroskopie der Technische Universitaet Dresden, c/o Forschungszentrum Rossendorf, Postfach 510119, D-01314 Dresden (Germany)
2. School of Physics, University of East Anglia, Norwich NR47TJ (United Kingdom)
3. Elektrika eta Elektronika Saila, Euskal Herriko Unibertsitatea, 644 p.k., 48080 Bilbo (Spain)
4. Institut fuer Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf, Postfach 510119, D-01314 Dresden (Germany)
5. Institut fuer Nukleare Festkoerperphysik, Universitaet der Bundeswehr Muenchen, D-85577 Neubiberg (Germany)

Radiation damage caused by the implantation of 200 keV Ge{sup +} ions into 6H-SiC has been studied by monoenergetic positron Doppler broadening and lifetime techniques. Specimens exposed to seven ion fluences ranging from 10{sup 16} to 10{sup 19} m{sup {minus}2}, together with unirradiated samples, were studied. The depth of the damaged crystalline layer was found to range from about 300 to 600 nm and, for ion fluences above 3{times}10{sup 17} m{sup {minus}2}, an amorphous layer is seen whose thickness increases to 133 nm at the highest fluence. Positron lifetime measurements, in combination with theoretical calculations, suggest that the main defect produced is the divacancy, but that Si monovacancies are also created. In the amorphous surface layer larger agglomerates consisting of at least four but more probably six vacancies are detected. Trapping rates are evaluated as a function of incident positron energy by applying the positron trapping model to the data. Values for defect concentrations in the damaged layers of about 50 ppm are deduced by invoking plausible assumptions; the problem of extracting defect profiles from the data is discussed. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 286667
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 5 Vol. 54; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
AMORPHOUS STATE
CRYSTAL DEFECTS
GERMANIUM IONS
ION IMPLANTATION
KEV RANGE 100-1000
LIFETIME
POSITRON DETECTION
RADIATION EFFECTS
SCANNING LIGHT MICROSCOPY
SILICON CARBIDES
TRAPPING
VACANCIES