METHOD FOR FORMING SPACERS FOR A TRANSITOR GATE
First Claim
Patent Images
1. A method for forming spacers for a gate of a field effect transistor, the gate being situated above a layer of semiconductor material, comprising:
- forming a layer of nitride covering the transistor gate;
after forming the layer of nitride, 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 modifying being performed so as not to modify the layer of nitride over its entire thickness at flanks of the gate, the modifying includes using a plasma comprising the light ions; and
removing the modified layer of nitride by 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.
0 Assignments
0 Petitions
Accused Products
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
38 Citations
30 Claims
-
1. A method for forming spacers for a gate of a field effect transistor, the gate being situated above a layer of semiconductor material, comprising:
-
forming a layer of nitride covering the transistor gate; after forming the layer of nitride, 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 modifying being performed so as not to modify the layer of nitride over its entire thickness at flanks of the gate, the modifying includes using a plasma comprising the light ions; and removing the modified layer of nitride by 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. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
-
28. A method of etching a layer of nitride selectively to silicon (Si) and/or silicon oxide (SiO2) comprising:
-
at least one step of modifying all or part of the layer of nitride by implantation of hydrogen (H2) or helium (He) in the layer of nitride in order to form a modified layer of nitride, wherein the at least one step of modifying comprises putting the layer of nitride in a presence of a plasma comprising light ions in an etching reactor; and at least one step of removing the modified layer of nitride by selective etching of the modified layer of nitride vis-à
-vis the silicon (Si) and/or silicon oxide (SiO2). - View Dependent Claims (29, 30)
-
Specification