Method for fabricating semiconductor device

1. A method for fabricating a semiconductor device, comprising the steps of:

(a) forming a first insulating film having moisture absorbency on a substrate;

(b) forming a dummy contact hole and a contact hole in the first insulating film, the contact hole going fully through the first insulating film;

(c) heat-treating the substrate, thereby removing water contained in the first insulating film;

(d) filling the contact hole and the dummy contact hole with a conductive material, thereby forming a contact and a dummy contact,

(e) after the step (d), forming, on the first insulating film, a second insulating film, in which a wiring groove is formed on the first insulating film and the contact; and

(f) filling the wiring groove with a conductive material, thereby forming an interconnect on the contact, wherein

in the step (b), the dummy contact hole and the contact hole are formed by the same step.

2. The method of claim 1 , wherein the step (c) is performed at least after the step (b) and before the step (d).

3. The method of claim 1 , wherein the step (c) is performed at least after the step (d).

4. The method of claim 3 , wherein the contact and the dummy contact include a first barrier metal film and a first metal film, the first barrier metal film being formed along inner faces of the contact hole and of the dummy contact hole and being made of an oxidizing metal, the first metal film being formed on the first barrier metal film to fill the contact hole and the dummy contact hole.

5. The method of claim 4 , wherein the first barrier metal film is made of at least one element selected from the group consisting of molybdenum, chromium, cobalt, platinum, and tungsten.

6. The method of claim 1 , wherein the step (c) is also performed after the step (e) and before the step (f).

7. The method of claim 6 , wherein a dummy wiring groove is also formed in the second insulating film; and

in the step (f), the dummy wiring groove is filled with a conductive material, thereby forming a dummy interconnect.

8. The method of claim 7 , wherein the interconnect and the dummy interconnect include a second barrier metal film and a second metal film, the second barrier metal film being formed along inner faces of the wiring groove and of the dummy wiring groove and being made of an oxidizing metal, the second metal film being formed on the second barrier metal film to fill the wiring groove and the dummy wiring groove; and

the step (c) is also performed after the step (e).

9. The method of claim 8 , wherein the second barrier metal film is made of at least one element selected from the group consisting of molybdenum, chromium, cobalt, platinum, and tungsten.

10. The method of claim 1 , wherein the heat treatment in the step (c) is performed in an atmosphere in which at least one element selected from the group consisting of nitride, oxygen, hydrogen, and rare gas is contained.

11. The method of claim 1 , wherein the heat treatment in the step (c) is performed at a temperature of 200° C. to 800° C.

12. The method of claim 1 , wherein the diameter of an opening of the dummy contact hole is 0.5 to 10 times a minimum size of the diameter of an opening of the contact hole.

13. The method of claim 1 , wherein a ratio of a sum total of areas of openings of all of the contact hole and the dummy contact hole to an entire area of the substrate is 0.1% to 50%.

14. The method of claim 1 , wherein an opening of the dummy contact hole is square, rectangular, or circular in shape.

15. The method of claim 1 , wherein the dummy contact hole does not go fully through the first insulating film.

16. A method for fabricating a semiconductor device, comprising the steps of:

(a) forming, on a substrate, a first insulating film in which a contact hole is formed and which has moisture absorbency;

(b) filling the contact hole with a conductive material, thereby forming a contact going fully through the first insulating film;

c) forming, on the first insulating film, a second insulating film, in which a wiring groove is formed on the contact and a dummy wiring groove is formed on the first insulating film;

(d) after the step (c), heat-treating the substrate, thereby removing water contained in the first insulating film; and

(e) filling the wiring groove and the dummy wiring groove with a conductive material, thereby forming an interconnect and a dummy interconnect, wherein

in the step (c), the dummy wiring groove and the wiring groove are formed by the same step.

17. The method of claim 16 , wherein the step (d) is performed at least before the step (e).

18. The method of claim 16 , wherein the interconnect and the dummy interconnect include a barrier metal film and a metal film, the barrier metal film being formed along inner faces of the wiring groove and of the dummy wiring groove and being made of an oxidizing metal, the metal film being formed on the barrier metal film to fill the wiring groove and the dummy wiring groove; and

the step (d) is performed at least after the step (e).

19. The method of claim 18 , wherein the barrier metal film is made of at least one element selected from the group consisting of molybdenum, chromium, cobalt, platinum, and tungsten.

20. The method of claim 16 , wherein the heat treatment in the step (d) is performed in an atmosphere in which at least one element selected from the group consisting of nitride, oxygen, hydrogen, and rare gas is contained.

21. The method of claim 16 , wherein the heat treatment in the step (d) is performed at a temperature of 200° C. to 800° C.

22. The method of claim 16 , wherein an opening of the dummy wiring groove is square, rectangular, or circular in shape.

23. The method of claim 16 , wherein the width of the dummy wiring groove is 0.5 to 100 times a minimum size of the width of the wiring groove.

24. The method of claim 16 , wherein a ratio of a sum total of areas of openings of all of the wiring groove and the dummy wiring groove to an entire area of the substrate is 0.1% to 80%.

25. The method of claim 1 , wherein the dummy contact is incapable of having current flow therethrough.

26. The method of claim 16 , wherein the dummy contact is incapable of having current flow therethrough.

27. The method of claim 1 , wherein the first insulating film has higher moisture absorbency than the second insulating film.

28. The method of claim 1 , wherein the dummy contact hole formed in the step (a) is formed to the vicinity of a lower surface of the first insulating film.

29. The method of claim 1 , wherein the dummy contact hole formed in the step (a) is formed so as to pass through the first insulating film.

30. The method of claim 1 , wherein after the step (f), an upper surface of the dummy contact has the same height as that of the contact.

31. A method for fabricating a semiconductor device, comprising the steps of:

(a) forming a first insulating film having moisture absorbency on a substrate;

(b) forming a dummy contact hole and a contact hole in the first insulating film, the contact hole going fully through the first insulating film;

(c) heat-treating the substrate, thereby removing water contained in the first insulating film; and

(d) filling the contact hole and the dummy contact hole with a conductive material, thereby forming a contact and a dummy contact, wherein

the dummy contact hole formed in the step (a) is formed to the vicinity of a lower surface of the first insulating film.

32. The method of claim 31 , wherein the dummy contact hole formed in the step (a) is formed so as to pass through the first insulating film.