A new low resistance MOS technology has been developed. An essential part of the new technology is ion implantation through metal film (ITM) to induce metal/Si interface mixing and also to form doped layers. The ITM technique enablds forming high quality refractory metal silicide overcoats on Si patterns with excellent self-alignability and reproducibility. Using the new technology, MOSFETs with self-aligned Mo-silicided gate and source/drain have been fabricated, even without any insulating spacers on gate side walls.