The leakage current improvement in an ultrashallow junction NMOS with Co silicided source and drain

The leakage current characteristics of the cobalt silicided NMOS transistor s with a junction depth of 800 Angstrom have been studied. In order to mini mize the junction leakage current, the thickness of the CoSi2 layer should be controlled under 300 Angstrom and the Si surface damage induced by the g ate spacer etch should be minimized. The post furnace annealing after the s econd silicidation by the rapid thermal annealing (RTA) process also affect ed the leakage current characteristics. The gate induced drain leakage (GID L) current was not affected by the lateral encroachment of CoSi2 layer into the channel direction when the gate spacer length was larger than 400 Angs trom.