NEW TI-SALICIDE PROCESS USING SB AND GE PREAMORPHIZATION FOR SUB-O.2 MU-M CMOS TECHNOLOGY

A new process for thin titanium self-aligned silicide (Ti-SALICIDE) on narrow n(+) poly-Si lines and n(+) diffusion layers using preamorphiz ation implantation (PAI) with heavy ions of antimony (Sb) and germaniu m (Ge) has been demonstrated for application to 0.2-mu m CMOS devices and beyond. Preamorphization enhances the phase transformation from C4 9TixSix to C54TiSi2 and lowers the transformation temperature by 80 de grees C so that it occurs before conglomeration in narrow lines. Pream orphization by Sb and Ge implantation yields better results than that by As. The sheet resistance of TiSi2 on heavily As doped poly-Si lines are 3.7 Omega/square and 3.8 Omega/square for the samples preamorphiz ed by Ge and Sb implantations even with line width down to 0.2 mu m. T here is less leakage in the Ti-SALICIDE diode with preamorphization th an without it. The probable reasons and mechanisms are discussed.