Method of manufacturing a semiconductor device and semiconductor device
View Patent ↗A method of manufacturing a semiconductor device has forming, in a dielectric film, a first opening and a second opening located in the first opening, forming a first metal film containing a first metal over a whole surface, etching the first metal film at a bottom of the second opening using a sputtering process and forming a second metal film containing a second metal over the whole surface, and burying a conductive material in the second opening and the first opening.
1. A method of manufacturing a semiconductor device, comprising:
forming a first wiring layer over a semiconductor substrate;
forming a dielectric film over the first wiring layer;
forming, in the dielectric film, a first opening and a second opening within the first opening which reaches the first wiring layer;
forming a first metal film containing a first metal over a surface of the first opening, the second opening, and the dielectric film;
etching the first metal film at a bottom of the second opening using a sputtering process and forming a second metal film containing a second metal over the surface of the first opening, the second opening, and the dielectric film;
burying a conductive material in the second opening and the first opening; and
in said forming the second metal film, a first Vd/Ve at the bottom of the second opening is smaller than a second Vd/Ve at the surface of the dielectric film, where Vd is a deposition rate and Ve is an etching rate.
2. The method according to claim 1 , further comprising:
after forming the first metal film, a third metal film containing the second metal is formed over the surface of the first opening, the second opening, and the dielectric film before forming the second metal film.
3. The method according to claim 1 , wherein
in forming the second metal film, a fourth metal film containing the first metal and the second metal is formed over a sidewall of the second opening.
4. The method according to claim 1 , wherein
any one of argon, helium, and xenon is used as a sputtering gas for formation of the second metal film.
5. The method according to claim 1 , wherein
the first metal includes any one of titanium, zirconium, and manganese, or alloys thereof.
6. The method according to claim 1 , wherein
the second metal includes any one of tantalum and tungsten, or alloys thereof.
7. The method according to claim 1 , wherein
the conductive material includes copper.
8. The method according to claim 7 , wherein burying the conductive material comprising:
forming a seed copper film over the surface of the first opening, the second opening, and the dielectric film; and
depositing a copper wiring film over the seed copper film using an electroplating method.
9. The method according to claim 8 , wherein
the seed copper film is formed by a sputtering process.
10. The method according to claim 1 further comprising:
after forming the second metal film, a fifth metal film containing the second metal is formed over the surface of the first opening, the second opening, and the dielectric film by a sputtering process before burying conductive material.