This paper describes a method for low reverse leakage current in n(+)/p titanium-silicided shallow junctions featuring mediated ion implantation of Ti silicide (MITS). After deposition of Ti film, a first heat treatment was performed to form C49 Ti silicide. MITS arsenic ions were implanted and a second heat-treatment was carried out at 850 degrees C to form C54 Ti silicide. in spite of no drive-in process following the second annealing, the implanted As diffused well into Si substrate and the reverse leakage current of the n+/p junctions was greatly reduced from 200 to 3 nA/cm(2). The reason for fast diffusivity is supposed to be the generation of high tensile stress induced by As implantation, while normal C49 Ti silicide film constantly shows compressive stress. This technique satisfies low sheet resistance (<5 Omega/square) and low leakage current of Ti silicided shallow junctions simultaneously. Therefore, we can conclude that C49 TiSi2 can be used as a diffusion source without causing further short-channel effects and punchthrough in sub-quarter micrometer n-MOSFETs.