Thermoelectric effect in very thin film Pt/Au thermocouples

The thickness dependence of the thermoelectric power of Pt films of variable thicknesses on a reference Au film has been determined for the case when the Pt film thickness, t, is not large compared to the charge-carrier mean free path. Pt film thicknesses down to 2.2 nm were investigated. We find that Delta S-F=S-B-S-F (where S-B and S-F are the thermopowers of the Pt bulk and film, respectively) does not vary linearly as 1/t is the case for thin film thermocouples when the film thickness is large compared to the charge-carrier mean free path. (c) 2006 American Institute of Physics.