Multi-level wiring using refractory metal

A semiconductor device comprising:

• an underlie having a first insulating layer;
• a first wiring comprising 90% or more of refractory metal, said first wiring being disposed on said first insulating layer;
• a second insulating layer formed on said first wiring and having a contact hole on a desired region of the first wiring;
• a second wiring comprising 90% or more of Al, said second wiring being disposed on said second insulating layer to be electrically connected to an upper surface of said first wiring at a region of said contact hole;
• and
• a barrier layer formed between said first and second wirings at a portion where said first and second wirings are electrically connected, said barrier layer being made of a material different from, and having a degree of reactivity which does not significantly effect the contact resistance between, the Al and the refractory metal,
• said device further comprising an oxidized surface layer formed on a surface of said barrier layer by slightly oxidizing a surface of said barrier layer.

A semiconductor device comprising:

• an underlie having a first insulating layer;
• a first wiring comprising 90% or more of refractory metal, said first wiring being disposed on said first insulating layer;
• a second insulating layer formed on said first wiring and having a contact hole on a desired region of the first wiring;
• a second wiring comprising 90% or more of Al, said second wiring being disposed on said second insulating layer to be electrically connected to an upper surface of said first wiring at a region of said contact hole;
• and
• a barrier layer formed between said first and second wirings at a portion where said first and second wirings are electrically connected, said barrier layer being made of a material different from, and having a degree of reactivity which does not significantly effect the contact resistance between, the Al and the refractory metal, wherein said barrier layer includes a first layer comprising Ti and a second layer comprising TiN, said second layer being formed on the first layer.

A semiconductor device comprising:

• an underlie having a first insulating layer;
• a first wiring comprising 90% or more of refractory metal, said first wiring being disposed on said first insulating layer;
• a second insulating layer formed on said first wiring and having a contact hole on a desired region of the first wiring;
• a second wiring comprising 90% or more of Al, said second wiring being disposed on said second insulating layer to be electrically connected to an upper surface of said first wiring at a region of said contact hole;
• and
• a barrier layer formed between said first and second wirings at a portion where said first and second wirings are electrically connected, said barrier layer being made of a material different from, and having a degree of reactivity which does not significantly effect the contact resistance between, the Al and the refractory metal, wherein said barrier layer includes a first layer comprising TiN and a second layer comprising Ti, said second layer being formed on the first layer.

A semiconductor device comprising:

• an underlie having a first insulating layer;
• a first wiring comprising 90% or more of refractory metal, said first wiring being disposed on said first insulating layer;
• a second insulating layer formed on said first wiring and having a contact hole on a desired region of the first wiring;
• a second wiring comprising 90% or more of Al, said second wiring being disposed on said second insulating layer to be electrically connected to an upper surface of said first wiring at a region of said contact hole;
• and
• a barrier layer formed between said first and second wirings at a portion where said first and second wirings are electrically connected, said barrier layer being made of a material different from, and having a degree of reactivity which does not significantly effect the contact resistance between, the Al and the refractory metal, wherein said barrier layer comprises a single TiN layer having an oxidized surface layer.