Offene Fragen zu atomaren Fehlstellen
Von G.F. Cerofolini (1989):
Having recently written a book on physical chemistry of, in and on
silicon [1], I have considered some of the most obvious queries which could be
raised when considering such a topic, viz.:
which is the atomic configuration of point defects? (e.g., is the
self- interstitial quasi free or does it have a dumb-bell configuration?)
has each defect only one configuration or are several configurations
possible?
which is the electronic structure?
which charge states are associated with each defect and where are
they located in the gap?
can the defect be actually considered pointlike (i.e., do the
remaining atoms remain on their lattice location) or does the deformation
extend to long range?
does an entropic or enthalpic barrier exist for Frenkel-pair
recombination?
which are the defect diffusivities in relation to their charge
states?
is the surface an effective generation-recombination centre for point
defects?
to which extent does this generation-recombination rate depend on
surface conditions (free, oxidated, nitridated, etc.)?
Most of them, however, remained unanswered.
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