The thermopower and resistivity of MexSi1−x(Me=Fe, Ir and Re) thin films have been investigated with compositions in the vicinity and outside of the stoichiometry of the corresponding semiconducting silicides.Insitumeasurements up to 1100 K give insight into crystallization processes during annealing of the as‐deposited amorphous films. Outside the stoichiometric compositions systematic changes of the thermopower on composition have been found, which are discussed on the basis of results from phase analysis. The behavior of the Re‐Si films is different in comparison with the other two systems because of the high degeneracy of the corresponding silicide ReSi2. ©1995 American Institute of Physics.