High mobility two-dimensional electron system on hydrogen-passivated silicon(111) surfaces

K. Eng; R. N. McFarland; B. E. Kane

doi:10.1063/1.2001734

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High mobility two-dimensional electron system on hydrogen-passivated silicon(111) surfaces

K. Eng·R. N. McFarland·B. E. Kane

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Abstract

We have fabricated and characterized a field-effect transistor in which an electric field is applied through an encapsulated vacuum cavity and induces a two-dimensional electron system on a hydrogen-passivated Si(111) surface. This vacuum cavity preserves the ambient sensitive surface and is created via room temperature contact bonding of two Si substrates. Hall measurements are made on the H-Si(111) surface prepared in aqueous ammonium fluoride solution. We obtain electron densities up to $6.5 \times 10^{11}$ cm$^{-2}$ and peak mobilities of $\sim 8000$ cm$^{2}$/V s at 4.2 K.

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K. Eng, R. N. McFarland, B. E. Kane. 2005-06-30. High mobility two-dimensional electron system on hydrogen-passivated silicon(111) surfaces. https://doi.org/10.1063/1.2001734

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