Anomalous Large Thermoelectric Power of the Si and Au Doped Ge Superlattice Thin Film

The thermoelectric properties of superlattice thin films have been studied as functions of temperature. The superlattice thin films were prepared by the alternate deposition of Si and Ge heavily doped with Au in ultrahigh vacuum. They have an intended artificial interval, but each layer is in an amorphous state. An anomalously large thermoelectric power and power factor is observed. The power factor reaches a maximum value of approximately 7 W/mK2 at around 800 K, which is anomalously large compared to that for conventional bulk materials.