Measurement of Seebeck coefficient of electroplated thermoelectric films in presence of a seed layer

Effect of the seed layer on Seebeck coefficient measurement of electroplated thermoelectric films was quantitatively analyzed. It is found thatsheet, rather than bulk resistance of the seed layer, or more precisely its relative comparison to sheet resistance of the film, determines the effects. The analysis reveals that the seed layer’s effect can be neglected (within 1% error) only if the sheet resistance ratio [R□2(film)/R□1(seed)] is smaller than 0.01. This condition commonly requires film thicknesses of 100 μm or more, which is not practically relevant. Based on the analysis we proposed a new method that is applicable for 10 times thinner films. This approach for determining Seebeck coefficient is simple, and more importantly, electroplated films can be characterized in their statu nascendi. Finite element simulation and experiments verified the analysis.