Thin film thermoelctric generators provide the possibility to arrange many thermoelements on little space due to miniaturization. Thus Seebeck-Voltages in a order of magnitude for usual low voltage applications can be achieved. Best suited thermoelectric materials at room temperature are bismuth-antimony-tellurides (highest thermoelectric effectivity Z=S2σ/κ, S-Seebeck-coefficient, σ - spec. electr. conductivity, κ - spec. heat conductivity). The thermoelectric properties of polycrystalline (Bi1-xSbx)2Te3-films should be optimised by varying growing conditions. The aim was to come closer to the single crystal properties as much as possible. Films with compositions x=0, 0.25, 0.5, 0.75, 0.85 were deposited on polyimid foils (Kapton ®) by means of dc-magnetron sputtering. Substrate temperatures TS from about 200°C up to about 320°C had been used. The temperatures of a "hot wall" environment varied from 150°C to 390°C. To avoid highly non-stoechiometric compositions of the films an additional tellurium source (additional flux of Te-particles) was used. Analysis of chemical composition with EBMA (WDX) showed nearly independent concentrations of tellurium on Te:(Bi,Sb) flux ratio and substrate temperature 220°CS Transport properties of importance for thermoelectricity are decisive influenced on Bi:Sb-ratio, substrate temperature, temperature of "hot-wall"-environment and a following annealing. Antimony richer films with x=0,85 have favourable thermoelectric properties (greater power factor S2σ) than films with x=0,75 (composition of the material with highest thermoelectric effectivity Z). The higher power factor in antimony richer films can be explained, at least qualitatively, with an experimental underpinned hypothesis about increase of carrier mobility at distinct tellurium contents in the films and the model of disorder (origin of carriers).