Polishing pad for a semiconductor substrate
AssigneeCabot Corporation
InventorsRoland K. Sevilla, Frank B. Kaufman, Sriram P. Anjur
Life of this patent
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Abstract
A polishing pad for polishing a semiconductor wafer which includes an open-celled, porous substrate having sintered particles of synthetic resin. The porous substrate is a uniform, continuous and tortuous interconnected network of capillary passage.
Claims27
A polishing pad substrate comprising sintered particles of thermoplastic resin, wherein said polishing pad substrate has a top surface having a mean unbuffed surface roughness and a bottom surface including a skin layer having a mean unbuffed surface roughness, wherein the pad top surface has a mean unbuffed surface roughness that is greater than the mean unbuffed surface roughness of the pad bottom surface skin layer.
A sintered urethane resin polishing pad substrate having a top surface, a bottom surface including a skin layer, wherein said substrate has a thickness of from 30-125 mils, a density of from 0.60 to 0.95 gm/cc, a pore volume of from 15-70%, a mean top surface roughness of from 4-50 microns and a mean bottom surface skin layer roughness of less than microns;
- and wherein the mean surface roughness of the bottom surface skin layer is less than the mean surface roughness of the top surface.
A sintered urethane resin polishing pad substrate having a top surface, a bottom surface including a skin layer, wherein said substrate has a thickness of from 35-70 mils, a density of from 0.70 to 0.90 gm/cc, a pore volume of from 25-50%, a mean top surface roughness of from 4-20 microns and a mean bottom surface skin layer roughness of less than 10 microns;
- and wherein the mean surface roughness of the bottom surface skin layer is less than the mean surface roughness of the top surface.
A polishing pad comprising;
- a. a polishing pad substrate further comprising sintere particles of thermoplastic resin, wherein said polishing pad substrate has a top surface having a mean unbuffed surface roughness and a bottom surface including a skin layer having a mean unbuffed surface roughness, wherein the pad top surface has a mean unbuffed surface roughness that is greater than the mean unbuffed surface roughness of the pad bottom surface;
- b. a backing sheet;
- and
- c. an adhesive located between the backing sheet and the bottom surface skin layer.
A polishing pad comprising;
- a. a sintered urethane resin polishing pad substrate having a top surface, a bottom surface including a skin layer, wherein said substrate has a thickness of from 30-125 mils, a density of from 0.60 to 0.95 gm/cc, a pore volume of from 15-70%, a mean top surface roughness of from 4-50 microns and a mean bottom surface skin layer roughness of less than 20 microns;
- and wherein the mean surface roughness of the bottom surface skin layer is less than the mean surface roughness of the top surface;
- b. a backing sheet;
- and
- c. an adhesive located between the backing sheet and the bottom surface skin layer.
A polishing pad substrate comprising sintered particles of thermoplastic resin, wherein said polishing pad substrate has a top surface having a mean unbuffed surface roughness and a bottom surface including a skin layer wherein the pad top surface has a mean surface roughness before buffing that is greater than the mean unbuffed surface roughness of the pad bottom surface skin layer.
Dependencies are inferred from the claim text.