| 摘要 |
PROBLEM TO BE SOLVED: To suppress over-etching upon a metal gate electrode when forming a contact on the metal gate electrode. SOLUTION: A first etching step is performed to a depth such that an offset nitride film is exposed from the surface of a layer insulating film after embedding a projecting laminate which is formed on a silicon substrate 12 and comprises a gate insulating film 14 into the layer insulating film 24, a metal gate electrode 16, a protecting film 18 and the offset nitride film 20; a second etching step is performed to expose the protecting film by performing etching removal upon the exposed silicon nitride film; and a third etching step is performed to expose the surface of the metal gate electrode by performing etching removal on the exposed protecting film, so that a contact part 261 is formed on the exposed metal gate electrode. In this case, the protecting film is made of a material of which the etching rate for a protecting film forming material in the third etching step is greater than an etching rate for a metal gate electrode forming material. COPYRIGHT: (C)2005,JPO&NCIPI
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