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Activation mechanisms in sodium-doped Silicon MOSFETs

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 نشر من قبل Thierry Ferrus
 تاريخ النشر 2005
  مجال البحث فيزياء
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We have studied the temperature dependence of the conductivity of a silicon MOSFET containing sodium ions in the oxide above 20 K. We find the impurity band resulting from the presence of charges at the silicon-oxide interface is split into a lower and an upper band. We have observed activation of electrons from the upper band to the conduction band edge as well as from the lower to the upper band. A possible explanation implying the presence of Hubbard bands is given.

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