Seebeck effect in disordered low dimensional interface structures

We have studied the physical and chemical interaction at the interface of a morphous Sb and Cu, by means of measurements of the Seebeck coefficient, S, and the resistance per square, R-square. The solid interfaces were prepare d in situ using a quenching technique near liquid He temperature. We have o bserved a thickness as well as temperature dependence of S of the Cu/Sb int erface at Cu thickness <3 nm. In this thickness range the low temperature ( <150 K) slope of S, S/T\(T-->0), increases when reducing the Cu coverage. F or thicknesses >3 nm an opposite effect is observed. In this region S/T\(T- ->0) increases with increasing Cu thickness, but the Ss are much smaller th an for thicknesses <3 nm. These dependences of S/T\(T-->0) are discussed ta king into account the thermopower of three-dimensional CuxSb1-x alloys and polycrystalline Cu films. Evidence has been found that for Cu thickness <3 nm the chemical interaction at the interface forms a homogeneous amorphous CuSb alloy. (C) 1999 Elsevier Science B.V. All rights reserved.