Chemical mechanical polishing (CMP) slurry for copper and method of use in integrated circuit manufacture

A method for polishing a cooper layer on an integrated circuit, the method comprising the steps of:

• forming a dielectric layer having a top surface;
• forming an opening in the dielectric layer;
• forming a layer comprising copper within the opening and over the top surface of the dielectric layer;
• and
• polishing the layer comprising copper with a polishing slurry comprising an oxidizing agent, a citrate salt, an abrasive slurry, and a solvent, wherein a portion of the layer comprising copper overlying the top surface of the dielectric layer is removed and a portion of the layer comprising copper remains and a opening.

The method for polishing a copper layer on an integrated circuit, the method comprising the steps of:

• forming a first dielectric layer;
• forming an etch stop layer over the first dielectric layer;
• forming a second dielectric layer over the etch stop layer wherein the second dielectric layer has a top surface;
• forming a via through the first dielectric layer;
• forming an interconnect trench through the second dielectric layer wherein the via underlies the interconnect trench;
• forming a barrier layer within the interconnect trench and the via;
• forming a layer comprising copper within the interconnect trench, within the via, over the top surface of the second dielectric layer, and over the barrier layer;
• and
• polishing the layer comprising copper with a slurry comprising an oxidizing agent, a citrate salt, an abrasive slurry, a triazole derivative, and a solvent, a portion of the layer comprising copper remains in the via and the interconnect trench while a portion of the layer comprising copper overlying the top surface of the second dielectric layer is removed.