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Activation mechanisms in sodium-doped Silicon MOSFETs

T. Ferrus·R. George·C. H. W. Barnes·N. Lumpkin·D. J. Paul·M. Pepper
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Abstract

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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T. Ferrus, R. George, C. H. W. Barnes, N. Lumpkin, D. J. Paul, M. Pepper. 2007-05-16. Activation mechanisms in sodium-doped Silicon MOSFETs. https://doi.org/10.1088/0953-8984%2F19%2F22%2F226216

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