Method of fabricating copper damascene

A method of fabricating a damascene layer, comprising:

• forming a first non-conductive layer over a semiconductor substrate;
• forming a first low-k dielectric layer over the first non-conductive layer;
• forming a second non-conductive layer over the first low-k dielectric layer;
• forming a second low-k dielectric layer over the second non-conductive layer;
• etching the first low-k dielectric layer and stopping at the first non-conductive layer to form a first opening and etching the second low-k dielectric layer and stopping at the second non-conductive layer to form a second opening;
• heating the substrate to convert the first non-conductive layer within the first opening into a first conductive layer and the second non-conductive layer within the second opening into a second conductive layer;
• filling the first opening and the second opening with a copper-containing material to form a first copper-containing plug and a second copper-containing plug, respectively;
• planarizing the first and second copper-containing plugs so that tops of the plugs are co-planar with a top of the second low-k dielectric layer;
• and
• heating the substrate to form a self-forming barrier layer on sidewalls of the first and second copper-containing plugs.

A method of fabricating a semiconductor device, comprising:

• forming a first metallization layer over a semiconductor substrate;
• forming a first non-conductive layer over the first metallization layer;
• forming a first low-k dielectric layer over the non-conductive layer, a second non-conductive layer over the first low-k dielectric layer, and a second low-k dielectric layer over the second non-conductive layer;
• etching a first opening, the first opening extending through the a second low-k dielectric layer, second non-conductive layer, and the first low-k dielectric layer, and exposing a portion of the first non-conductive layer;
• etching a second opening, the second opening extending through the a second low-k dielectric layer and exposing a portion of the second non-conductive layer;
• applying a heat treatment to convert the exposed portion of the first non-conductive layer to a first conductive portion and to convert the exposed portion of the second non-conductive layer to a second conductive portion;
• filling the first opening with a conductive material and filling the second opening with conductive material;
• and
• heating the device to form a self-forming barrier layer on sidewalls of the conductive material.