High temperature stability of platinum silicide, formed by reacting metal with silicon or by cosputtering metal and silicon in a desired ratio, has been studied. The properties of films, thus formed, were examined as a function of annealing temperature using a resistance measuring technique, Rutherford backscattering, Auger and x‐ray analyses, transmission and scanning electron microscopic techniques, and by measuring forward current‐voltge (I‐V) characteristics of the siliciden‐silicon Schottky diodes. It is shown that cosputtering silicon rich alloys prevents agglomeration of the silicide, but increases the resistivity and decreases the Schottky barrier height of the film. Platinum silicide dissolves increasing amounts of silicon on high temperature (700–1000 °C) treatments causing considerable degradation of properties. Although cosputtering silicon rich alloys reduces this behavior, electrical properties such as forwardI‐Vcharacteristics still degrade due to high temperature anneals.