Chemical Mechanical Polishing (CMP) of Cobalt-Containing substrate

A method of a selective chemical mechanical polishing comprising:

• a) providing a semiconductor substrate having a surface containing a first material and at least one second material;
• wherein the first material is Co and the second material is selected from the group consisting of dielectric film, low-k and ultra low-k film, and barrier film;
• b) providing a polishing pad;
• providing a chemical mechanical polishing composition comprising
• 0.005 wt. % to 25 wt. % of abrasive;
• 0.05 wt. % to 5 wt. % of α-alanine;
• from 2 ppm to 100 ppm of phosphate compound comprising H2PO41−, HPO42−, or PO43−;
• 0.0005 wt. % to 0.25 wt. % of corrosion inhibitor;
• 0.005 wt. % to 10 wt. % of oxidizer;
• water;
• and
• the chemical mechanical polishing (CMP) polishing composition having a pH from 2.0 to about 12;
• and optionally 0.0001 wt. % t to 0.20 wt. % of amine compound;
• 0.01 wt. % to 10 wt. % of chelating agent;
• 0.01 wt. % to 0.5 wt. % of pH adjusting agent;
• 0.00001 wt. % to 0.10 wt. % of biocide;
• and
• 0.0005 wt. % to 0.15 wt. % of surfactant;
• and
• c) polishing the surface of the semiconductor substrate to selectively remove the first material;
• wherein at least a portion of the surface is in contact with both the polishing pad and the chemical mechanical polishing composition;
• and ratio of removal rate of the first material to removal rate of the second material is equal or greater than 50.

A chemical mechanical polishing (CMP) system comprising:

• a semiconductor substrate having a surface containing a first material and at least one second material;
• wherein the first material is Co and the second material is selected from the group consisting of dielectric films (such as TEOS, SixNy (with 1.0<x<3.0, 1.33<y<4.0), low-k and ultra low-k films, and barrier films (such as Ta, TaN, Ti, and TiN films);
• a polishing pad;
• a chemical mechanical polishing composition comprising
• 0.005 wt. % to 25 wt. % of abrasive;
• 0.05 wt. % to 5 wt. % of α-alanine;
• from 2 ppm to 100 ppm of phosphate compound comprising H2PO41−, HPO42−, or PO43−;
• 0.0005 wt. % to 0.25 wt. % of corrosion inhibitor;
• 0.005 wt. % to 10 wt. % of oxidizer;
• water;
• the chemical mechanical polishing (CMP) polishing composition having a pH from 2.0 to about 12;
• and optionally:
• 0.0001 wt. % t to 0.20 wt. % of amine compound;
• 0.01 wt. % to 10 wt. % of chelating agent;
• 0.01 wt. % to 0.5 wt. % of pH adjusting agent;
• 0.00001 wt. % to 0.10 wt. % of biocide;
• and
• 0.0005 wt. % to 0.15 wt. % of surfactant;
• and
• wherein at least a portion of the surface is in contact with both the polishing pad and the chemical mechanical polishing composition.