Temperature And Thickness Dependence Of The Thermopower Of Disordered Au-Films And Sb/Au Double-Layers

The thermopower S of disordered Au films is investigated for thicknesses d(Au)>5nm. While for d(Au)>25nm S/T is independent of d(Au), S/T decreases with decreasing d(Au) for d(Au)<25nm. This behaviour is discussed in terms of scattering from grain boundaries, voids and channels. Using insulating a-Sb (d(Sb)=12nm) as an interlayer between the Au and the substrate it is possible to investigate S(T) for d(Au)>0.4nm. Now S/T increases with decreasing d(Au) for d(Au)<2nm. The data of the double layers are discussed similar as S(T) of a-Au(x)Sb1-x near the metal-insulator transition. This similarity is also observed in the UPS/XPS spectra of a-Au(x)Sb1-x and the Sb/Au double layers.