Abstract: The invention relates to a method for forming spacers for a gate of a field effect transistor, the gate being situated above a layer of semiconductor material, comprising a step of forming a layer of nitride covering the transistor gate, the method being characterized in that it comprises: after the step of forming the layer of nitride, at least one step of modifying the layer of nitride by implantation of light ions in the layer of nitride in order to form a modified layer of nitride, the step of modification being performed so as not to modify the layer of nitride over its entire thickness at flanks of the gate, the step of modifying the layer of nitride by implantation being performed using a plasma comprising the light ions; at least one step of removing the modified layer of nitride by means of a selective etching of the modified layer of nitride vis-à-vis said semiconductor material and vis-à-vis the non-modified layer of nitride