It was recalled that Pd was known to exhibit an acceptor state at Ec - 0.22eV in n-type material, and a donor state at Ev + 0.31eV in p-type material. A third level, at Ev + 0.14eV, was identified here and was attributed to the double-donor state of substitutional Pd. The Pd level positions were very similar to the corresponding levels for Pt. The double-donor states of both metals exhibited an electric field dependence of the emission rates, and a thermal activation of the hole-capture cross-sections.

J.U.Sachse, W.Jost, J.Weber, H.Lemke: Applied Physics Letters, 1997, 71[10], 1379-81