Implementation of a TiN cap layer into conventional self-aligned RTP titanium disilicide MOS process

The silicide growth over the spacers (bridging) in the conventional self-aligned silicide process using titanium disilicide is dominated by the lateral diffusion of Si atoms from the gate and source/drain areas. A TiN cap layer, which has been suggested to minimize the bridging problem was studied. The influence of such a capping layer on the reaction between Ti and Si, on the lateral diffusion of Si, and on the electrical properties of the TiSi2-Si contact was investigated.