Metal interconnection structure of a semiconductor device having low resistance and method of fabricating the same
Provided is a metal interconnection structure of a semiconductor device, including a first metal film pattern disposed on an upper part of an insulation film of a semiconductor substrate; an intermetallic dielectric film having a metal contact plug in which a barrier layer, a metal film for contact plug and a second metal film are sequentially disposed, on the first metal film pattern; and a second metal film pattern disposed on the metal contact plug and intermetallic dielectric film and connected to the metal contact plug.
1. A metal interconnection structure of a semiconductor device having a low resistance, comprising:
a first metal film pattern disposed on an upper part of an insulation film of a semiconductor substrate;
an intermetallic dielectric film disposed on the first metal film pattern and the insulation film, and having a via-hole exposing an upper surface of the first metal film pattern;
a metal barrier layer disposed on side walls and a lower surface of the via-hole;
a first metal contact plug disposed on a lower part of the via-hole such that the first metal contact plug connects the upper surface of the first metal film pattern through the metal barrier layer, and made of a metal film having a first specific resistance;
a second metal contact plug disposed on the upper part of the first metal contact plug while filling the upper part of the via-hole, and made of a metal film having a second specific resistance lower than the first specific resistance; and
a second metal film pattern disposed on the second metal contact plug and intermetallic dielectric film.
2. The metal interconnection structure according to claim 1 , wherein the first metal contact plug is disposed within 65% of the height of the via-hole from the lower part thereof.
3. The metal interconnection structure according to claim 1 , wherein the first metal contact plug is formed of a tungsten film, and the second metal contact plug is formed of an aluminum film.
4. The metal interconnection structure according to claim 1 , wherein the second metal film pattern is the same metal film as the second metal contact plug.
5. The metal interconnection structure according to claim 1 , wherein the second metal film pattern is formed of an aluminum film or a copper film.