Thermoelectric transport properties of ReSi_(1.75) thin films

摘要

Epitaxial ReSi_(1.75) thin films of variable thickness between 15nm and 150nm have been prepared in an one step process by Facing Target Sputtering (FTS) onto heated (100) and (111)Si and SOS wafers. The epitaxial relations and film structure have been investigated by X-ray diffraction and transmission electron microscopy. Epitaxial growth was found at a substrate temperature of 1070K. Thermoelectric properties were measured between 100K and 450K and compared to the transport behavior of builk ReSi_(1.75) and polycrystalline films. A distinct dependence of both the conductivity and thermopower was found on the film thickness, on unintentional doping and on the film structure. The results show that epitaxial ReSi_(1.75) films prepared by FTS can be a basis for further investigations of thermoelectric silicide/silicon multilayers.