Abstract: A method inhibits metal silicide encroachment in channel regions in a transistor that uses metal silicide as an electrical contact to its terminals. A metal layer is deposited overlying the transistor. A first anneal that is a low temperature anneal forms metal silicide regions to source, gate and drain terminals of the transistor. The low temperature inhibits lateral encroachment. Unsilicided portions of the metal are removed and followed by an ion implant of an element, such as nitrogen, that diffuses into the metal silicide regions. A second anneal at a higher temperature than the first anneal is completed wherein the implanted nitrogen ions prevent lateral encroachment of metal silicide.

Abstract: In a semiconductor device, a relatively deep germanium implant and activation thereof precedes deposition of the nickel for nickel silicide formation. The activation of the germanium causes the lattice constant in the region of the implant to be increased over the lattice constant of the background substrate, which is preferably silicon. The effect is that the lattice so altered avoids formation of nickel disilicide. The result is that the nickel silicide spiking is avoided.

Abstract: A polysilicon line (22), used e.g. as a gate, has a portion (30) amorphized by implanting (19) particles having a relatively large atomic mass. The amorphized portion is used to form a metal silicide (38) having a desirably low sheet resistance. Exemplary metals are cobalt and nickel that can provide the thin lines of below 50 nanometers. An exemplary particle for implanting that has sufficient atomic mass is xenon. The dose and the energy of the implant (19) are potentially different based on the linewidth (21) of the polysilicon line (22).