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The fundamental properties of deep luminescence centres in Si
associated with transition metals such as Cu, Ag, Au, and Pt have
been a focus of interest for decades, both as markers for these
deleterious contaminants, and also in the quest for efficient
Si-based light emission. This dissertation presents the results of
ultra-high resolution photoluminescence studies of these centres in
specially prepared, highly enriched 28-Si samples. The greatly
improved spectral resolution due to this enrichment led to the
discovery of isotopic fingerprints. These fingerprints have
revealed that the detailed constituents of all of the centres
previously studied had been identified incorrectly. They also
revealed the existence of several different families of impurity
complexes containing either four or five atoms chosen from Li, Cu,
Ag, Au, and Pt. These centres' constituents have been determined,
together with no-phonon transition energies, no-phonon isotope
shifts, local vibrational mode energies, and the isotope shifts of
the local vibrational mode energies. The data presented here for
these centres should prove useful for the currently sought
theoretical explanations of their formation, stability, and
properties.
The fundamental properties of deep luminescence centres in Si
associated with transition metals such as Cu, Ag, Au, and Pt have
been a focus of interest for decades, both as markers for these
deleterious contaminants, and also in the quest for efficient
Si-based light emission. This dissertation presents the results of
ultra-high resolution photoluminescence studies of these centres in
specially prepared, highly enriched 28-Si samples. The greatly
improved spectral resolution due to this enrichment led to the
discovery of isotopic fingerprints. These fingerprints have
revealed that the detailed constituents of all of the centres
previously studied had been identified incorrectly. They also
revealed the existence of several different families of impurity
complexes containing either four or five atoms chosen from Li, Cu,
Ag, Au, and Pt. These centres' constituents have been determined,
together with no-phonon transition energies, no-phonon isotope
shifts, local vibrational mode energies, and the isotope shifts of
the local vibrational mode energies. The data presented here for
these centres should prove useful for the currently sought
theoretical explanations of their formation, stability, and
properties.
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Social Responsibility Standards, zeigt den Nutzen von CSR fr die
Unternehmen auf, beleuchtet den aktuellen Stand der
Nachhaltigkeitsberichterstattung, informiert ber die Bedeutung und
Verbreitung der Global Reporting Initiative (GRI) und schliet mit
einem Vergleich von Nachhaltigkeitsberichten europischer und
sdamerikanischer Unternehmen.
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