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arXiv · 1111.2785

Controlled oxygen vacancy induced p-type conductivity in HfO{2-x} thin films

Erwin Hildebrandt·Jose Kurian·Mathis M. Müller·Thomas Schroeder·Hans-Joachim Kleebe·Lambert Alff
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Abstract

We have synthesized highly oxygen deficient HfO$_{2-x}$ thin films by controlled oxygen engineering using reactive molecular beam epitaxy. Above a threshold value of oxygen vacancies, p-type conductivity sets in with up to 6 times 10^{21} charge carriers per cm3. At the same time, the band-gap is reduced continuously by more than 1 eV. We suggest an oxygen vacancy induced p-type defect band as origin of the observed behavior.

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Erwin Hildebrandt, Jose Kurian, Mathis M. Müller, Thomas Schroeder, Hans-Joachim Kleebe, Lambert Alff. 2011-11-11. Controlled oxygen vacancy induced p-type conductivity in HfO{2-x} thin films. https://doi.org/10.1063/1.3637603

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