Methods of forming a contact hole in a semiconductor device
View Patent ↗Methods for forming a contact hole in a semiconductor device are disclosed. A disclosed method is capable of preventing voids from being formed in a contact hole or a via hole. In particular, when a metal insulation film or an interlayer insulation film is selectively etched to form a contact hole or a via hole, a top edge of the contact hole or the via hole is rounded by using a plasma having spiral movement.
1. A method for forming a contact hole or a via hole in a semiconductor device comprising:
applying, exposing and developing a photosensitive film on a planarized metal insulation film or a planarized interlayer insulation film to form a photosensitive film pattern on a region to contain the contact hole or the via hole; and
dry etching the planarized metal insulation film or the planarized interlayer insulation film using the photosensitive film pattern as a mask and using a plasma having spiral movement sufficiently to form the contact hole or the via hole and round a top edge of the contact hole or the via hole thereby.
2. A method as defined in claim 1 , wherein, the plasma comprises a fluorine-containing etching gas.
3. A method as defined in claim 1 , further comprising:
after forming the contact hole or the via hole, forming a barrier metal film on an inner wall of the contact hole or the via hole; and
filling the contact hole or the via hole with a metal material.
4. A method as defined in claim 3 wherein filling the contact hole or the via hole with the metal material comprises forming the metal material on the barrier metal film.
5. A method as defined in claim 3 , further comprising:
after forming the contact hole or the via hole, forming a barrier metal film on an inner wall of the contact hole or the via hole; and
filling the contact hole or the via hole with a metal material.
6. A method as defined in claim 5 wherein filling the contact hole or the via hole with the metal material comprises forming the metal material on the barrier metal film.
7. The method of claim 1 , wherein the dry etching step is performed in an asher.
8. The method of claim 1 , wherein the dry etching step comprises rotating the plasma in a magnetic field, the magnetic field generated by a coil surrounding a chamber under a state where an electric field is applied vertically downward in the chamber.
9. A method for forming a contact hole or a via hole in a semiconductor device comprising:
applying, exposing and developing a photosensitive film on a planarized insulation film to form a photosensitive film pattern; and
dry etching the planarized insulation film using the photosensitive film pattern as a mask and using a plasma having spiral movement sufficiently to form the contact hole or the via hole and round a top edge of the contact hole or the via hole thereby.
10. A method as defined in claim 9 , wherein the insulation film comprises a metal insulation film.
11. A method as defined in claim 9 , wherein the insulation film comprises an interlayer insulation film.
12. A method as defined in claim 9 , wherein the plasma comprises a fluorine-containing etching gas.
13. A method us defined in claim 9 , further comprising:
after forming the contact hole or the via hole, forming a barrier metal film on an inner wall of the contact hole or the via hole; and
filling the contact hole or the via hole with a metal material.
14. A method as defined in claim 13 wherein filling the contact hole or the via hole with the metal material comprises forming the metal material on the barrier metal film.
15. A method as defined in claim 12 , further comprising:
after forming the contact hole or the via hole, forming a barrier metal film on an inner wall of the contact hole or the via hole; and
filling the contact hole or the via hole with a metal material.
16. A method as defined in claim 15 wherein filling the contact hole or the via hole with the metal material comprises forming the metal material on the barrier metal film.
17. The method of claim 9 , wherein the dry etching step is performed in an asher.
18. The method of claim 9 , wherein the dry etching step comprises rotating the plasma in a magnetic field, the magnetic field generated by a coil surrounding a chamber under a state where an electric held is applied vertically downward in the chamber.