High thermal stability and low junction leakage current of Ti capped Co salicide and its feasibility for high thermal budget CMOS devices

Abstract

A thermally stable cobalt salicide has been fabricated using Ti-capping Co/Si system. A Ti-capping layer is shown to improve the interfacial roughness and thermal stability of CoSi/sub 2/ film grown on Si substrate comparing with TiN-capping. It is attributed to high amount of Ti atoms in Co disilicide film, which slow down the agglomeration. According to the results of salicided gate and junction, Ti capped CoSi, had stable characteristics when the thermal budget increased up to 850/spl deg/C for 90 min. Therefore, Ti-capping Co salicide structure can be acceptable to fabricate DRAM and LOGIC-embedded DRAMs.