Effect of lateral dimensional scaling on the thermal stability of thin CoSi2 layers reacted on polycrystalline silicon

The thermal stability of patterned cobalt silicide layers grown on polycrys talline silicon was studied by electrical and morphological analyses in the temperature range of 850-1000 degrees C. The strip degradation upon anneal ing resulted in a faster resistance increase than that in blanket films, an d occurred from preferential agglomeration of the grains located at the str ip edges. An activation energy for this process of 3.5 eV was obtained by t he increase in resistance and attributed to the growth of silicon gains fro m the substrate that protruded into the silicide layer. (C) 2000 American V acuum Society. [S0734-211X(00)07902-6].