Patent ID: 7638427
Filing Date: 2009-12-29
Classification: H01L

Abstract:
1. A process for producing an MOS transistor, comprising the following steps: a) production of an initial gate structure above a semiconductor substrate, said initial structure comprising: b) formation of two portions of a compound of the type comprising a silicide of a first metal on the surface of the substrate, in source and drain zones of the transistor that are located on either side of the gate structure; c) formation of two coatings that are impermeable to-atoms of a second metal, on the silicide portions of the source and drain zones, respectively; d) deposition of a layer of the second metal on the gate structure and in the source and drain zones so that part of the second metal is in contact with the gate portion; and e) heating of the transistor so as to induce a silicidation reaction between the second metal and the silicon material of the gate portion, wherein step e) comprises: e1) first heating of the transistor so as to form an intermediate silicide-type compound from the second metal and from part of the silicon material of the gate portion; e2) removal of part of the second metal that has not participated in the formation of said intermediate compound; and e3) second heating of the transistor so as to form a final silicide-type compound of the second metal in part of the gate portion which is in contact with the gate dielectric layer.