Semiconductor device and method of fabricating the same
View Patent ↗A method of fabricating a semiconductor device according to one embodiment includes: forming a fin and a film on a semiconductor substrate, the film being located at least either on the fin or under the fin and on the semiconductor substrate; forming a gate electrode so as to sandwich both side faces of the fin via a gate insulating film; and expanding or shrinking the film, thereby generating a strain in a height direction of the fin in a channel region.
1. A semiconductor device, comprising:
a fin formed on and extending-vertically from a semiconductor substrate and having a strain in a vertical direction in a channel region therein, the fin being composed of Si;
gate insulating films formed vertically on opposed sides of said fin;
a gate electrode formed so as to sandwich the gate insulating films on both side faces of a portion of the fin including the channel region; and
a film formed at least either directly on or directly under a portion of the fin including the channel region, the film configured to generate a strain to the portion of the fin, the film comprising a SiGe oxide film or a Ge oxide film for generating a compressive strain in the vertical direction in the channel region of the fin, or a Si oxide film for generating a tensile strain in the vertical direction in the channel region of the fin,
wherein the film is formed only between the gate insulating films at least either at a position covering the whole upper surface of the fin or a position covering the whole lower surface of the fin.
2. The semiconductor device according to claim 1 , wherein the film is formed at least on the fin; and
a cap layer is formed on the film on the fin.
3. The semiconductor device according to claim 2 , wherein the film is formed by using oxidation treatment or heat treatment; and
the oxidation treatment or the heat treatment is carried out after forming the cap layer.
4. The semiconductor device according to claim 1 , wherein the fin is connected to a pad;
the film is formed at least either on or under the fin and the pad; and
a portion of the film including a center of a region contacting with the pad does not have a property of generating a strain in the fin.
5. The semiconductor device according to claim 4 , wherein the film is formed at least on the tin and the pad; and
a cap layer is formed on the film on the fin and the pad.
6. The semiconductor device according to claim 5 , wherein the film is formed by using oxidation treatment or heat treatment; and
the oxidation treatment or the heat treatment is carried out after forming the cap layer.
7. The semiconductor device according to claim 5 , wherein the film is formed by using oxidation treatment or heat treatment; and
the oxidation treatment or the heat treatment is carried out before forming the gate electrode.
8. The semiconductor device according to claim 4 , wherein the film is formed by oxidation treatment of a Si 1-x Ge x (0<x≦1) crystal.
9. The semiconductor device according to claim 8 , wherein the oxidation treatment is carried out using burning oxidation.
10. The semiconductor device according to claim 8 , wherein the oxidation treatment is carried out after forming the gate electrode.
11. The semiconductor device according to claim 4 , wherein the film is formed by heat treatment of an ozone TEOS film.
12. The semiconductor device according to claim 11 , wherein the heat treatment is carried out after forming the gate electrode.
13. The semiconductor device according to claim 4 , wherein the film is formed by using oxidation treatment or heat treatment; and
the oxidation treatment or the heat treatment is carried out before forming the gate electrode.
14. The semiconductor device according to claim 1 , wherein the film is formed by oxidation treatment of a Si 1-x Ge x (0<x≦1) crystal.
15. The semiconductor device according to claim 14 , wherein the oxidation treatment is carried out using burning oxidation.
16. The semiconductor device according to claim 14 , wherein the oxidation treatment is carried out after forming gate electrode.
17. The semiconductor device according to claim 1 , wherein the film is formed by heat treatment of an ozone TEOS film.
18. The semiconductor device according to claim 17 , wherein the heat treatment is carried out after forming the gate electrode.