Patent ID: 9607840
Date: 2017-03-28
CPC Classifications: H01L

Claim:
1. A method for forming spacers of a gate of a field-effect transistor, with the gate having a top and flanks and being located above an active layer in a semiconductor material, comprising: forming a protective layer covering the gate, with the protective layer having a dielectric constant that is less than or equal to 8; after the forming the protective layer, at least one step of forming a carbon film on the transistor; after the forming the carbon film, at least one step of removing the carbon film on a top of the gate and on either side of the gate by putting the carbon film into presence with a plasma, creating a bombardment of ions that are heavier than hydrogen ions according to a main direction so as to remove at least portions of the carbon film located on the top and on either side of the gate and which are perpendicular to said main direction, and leaving in place residual portions of the carbon film on the flanks of the gate; at least one step of modifying the protective layer by putting the protective layer into presence with a plasma containing ions with a hydrogen base (H, H after the modifying the protective layer, the forming the carbon film, and the removing at least the portions of the carbon film leaving in place residual portions of the carbon film on the flanks of the gate, performing at least one step of removing the modified protective layer using a selective etching of the modified protective layer with respect to the unmodified portions of the protective layer and with respect to the residual portions of the carbon film, wherein the forming the carbon film and the modifying the protective layer are not carried out simultaneously.