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

Abstract

The thermal stability of patterned cobalt silicide layers grown on polycrystalline silicon was studied by electrical and morphological analyses in the temperature range of 850–1000 °C. The strip degradation upon annealing resulted in a faster resistance increase than that in blanket films, and occurred from preferential agglomeration of the grains located at the strip edges. An activation energy for this process of 3.5 eV was obtained by the increase in resistance and attributed to the growth of silicon grains from the substrate that protruded into the silicide layer.