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arXiv · 2401.16887

Electrical characterization of all-epitaxial Fe/GaN(0001) Schottky tunnel contacts

Sergio Fernàndez-Garrido·Kai U. Ubben·Jens Herfort·Cunxu Gao·Oliver Brandt
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Abstract

We analyze the properties of Fe Schottky contacts prepared in situ on n-type GaN(0001) by molecular beam epitaxy. In particular, we investigate the suitability of these epitaxial Fe layers for electrical spin injection. Current-voltage-temperature measurements demonstrate pure field emission for Fe/GaN:Si Schottky diodes with [Si] = 5 $\times$ 10$^{18}$ cm$^{-3}$. The Schottky barrier height of the clean, epitaxial Fe/GaN interface is determined by both current-voltage-temperature and capacitance-voltage techniques to be (1.47 $\pm$ 0.09) eV.

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Sergio Fernàndez-Garrido, Kai U. Ubben, Jens Herfort, Cunxu Gao, Oliver Brandt. 2024-01-30. Electrical characterization of all-epitaxial Fe/GaN(0001) Schottky tunnel contacts. https://doi.org/10.1063/1.4737905

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