Degradation of the Poly-Si/Silicide Structure in Advanced MOS-Technologies

The interaction in the system poly-Si on TiSi 2 on Si and in the polycide system both with CoSi 2 and TiSi 2 is investigated when subjected to furnace heat treatments at high temperature. It will be shown that the first system suffers from instability due to SPE-regrowth which is partially avoided by doping the poly-Si. The polycide system shows severe roughening of the TiSi 2 . However, in the case of CoSi 2 , the degradation is more pronounced, viz. the Co is detected all over the poly-Si layer and this can hardly be suppressed by doping of the CoSi 2 -layer.