  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.
