Method of fabricating a fin field effect transistor in a semiconductor device
View Patent ↗A method for fabricating a fin FET in a semiconductor device. The method includes sequentially depositing first and second insulation films on a semiconductor substrate, etching the first and second insulation films using a first mask to form a trench, and depositing a first conductor in the trench.
1. A method for fabricating a fin field effect transistor comprising:
sequentially depositing a first insulation film and a second insulation film over a semiconductor substrate;
etching the first insulation film and the second insulation film using a first mask to form a trench on which a fin shaped conductor is to be formed; depositing a first conductor on the first and the second insulation films in which the trench is formed, thereby forming the fin shaped conductor;
depositing a gate insulation film and a gate conductive layer over the first insulation film and the fin conductor;
dry-etching the gate conductive layer using a second mask to form a gate conductor;
depositing a spacer film, forming a spacer on a side wall of the gate conductor by an overall etching method, and then forming a source and drain by a source and drain ion implantation process; and
performing a salicide process on exposed portions of the gate conductor and fin conductor to form a salicide film.
2. The method of claim 1 , wherein the first insulation film is an oxide film.
3. The method of claim 1 , wherein a thickness of the first insulation film ranges from about 1,000 Å to about 5,000 Å.
4. The method of claim 1 , wherein the first insulation film serves as a device isolation oxide film.
5. The method of claim 1 , wherein the second insulation film is a nitride film.
6. The method of claim 1 , wherein a thickness of the second insulation film ranges from about 500 Å to about 3,000 Å.
7. The method of claim 1 , wherein the first and the second insulation films are dry-etched.
8. The method of claim 1 , further comprising planarizing the deposited first conductor using chemical mechanical polishing to form the fin conductor after depositing the first conductor on the first and the second insulation films.
9. The method of claim 8 , wherein the second insulation film is used as an etching stop layer in the chemical mechanical polishing process.
10. The method of claim 1 , wherein the first conductor is formed by using at least one of chemical vapor deposition and selective polysilicon deposition.
11. The method of claim 1 , wherein the second insulation film is removed using a phosphoric acid solution.
12. The method of claim 1 , wherein the gate conductive layer includes one selected from a group including polysilicon, TiN, Ti and TiN, and compounds of tungsten and nitrogen (WxNy).
13. The method of claim 1 , wherein the gate insulation film is formed by at least one of oxidation, physical vapor deposition, chemical vapor deposition, and atomic layer deposition.
14. The method of claim 1 , wherein the spacer includes at least one of a nitride film and an oxide film.
15. The method of claim 1 , wherein the spacer includes a mixed film of nitride and oxide.
16. The method of claim 1 , further comprising the step of performing a well implant and a Vt-adjust implant by an ion implantation process on the planarized surface, before depositing the gate insulation film and the gate conductive layer.
17. The method of claim 1 , further comprising carrying out a lightly doped ion implantation process on the substrate, in which the gate conductor is formed, to form a lightly doped drain implant region before depositing the spacer film.