A thermally stable salicide process using N/sub 2/ implantation into TiSi/sub 2/

TiSi/sub 2/ is an appropriate candidate for the self-aligned silicide (salicide) process. However, it degrades morphologically and the film sheet resistance increases during high-temperature annealing. A thermally stable salicide process using N/sub 2/ implantation into TiSi/sub 2/ has been developed in order to retard this phenomenon. The morphology of the TiSi/sub 2/ film and the film sheet resistance were evaluated as a function of implanted N/sub 2/ dose after high-temperature annealing. The sample which received the highest dose exhibited the best film morphology, while there is an optimum dose for maintaining the film sheet resistance at its maximum value. The dependence of sheet resistance on implanted N/sub 2/ dose is discussed in terms of agglomeration, film composition, and implantation damage. A successful application to a submicron MOS transistor is presented.>