Abstract: The invention provides a method of forming porous polyurethane polishing pad that includes feeding liquid polyurethane onto a web sheet with a doctor blade while back tensioning the web. Coagulating liquid polyurethane onto the web sheet forms a two-layer substrate. The two-layer substrate has a porous matrix wherein the porous matrix has large pores extending upward from a base surface and open to an upper surface. Spring-arm sections connect lower and upper sections of the large pores.

Abstract: The invention provides a porous polyurethane polishing pad that includes a porous matrix. The matrix has large pores that extend upward from a base surface and open to an upper surface. The large pores are interconnected with tertiary pores, a portion of the large pores is open to a top polishing surface and at least a portion of the large pores extend to the top polishing surface. Spring-arm sections connect lower and upper sections of the large pores. The spring-arm sections all are in a same horizontal direction as measured from the vertical orientation and they combine for increasing compressibility of the polishing pad and contact area of the top polishing surface during polishing.

Abstract: The invention provides a porous polyurethane polishing pad that includes a porous matrix having large pores that extend upward from a base surface and open to an upper surface. The large pores extend to the top polishing surface and have lower and upper sections with a vertical orientation. The lower and upper sections are offset in a horizontal direction. Middle-sized pores with a columnar shape and a vertical orientation originate adjacent the middle sections and small pores with a columnar shape and a vertical orientation originate between the middle-sized pores. The pores combine for increasing compressibility of the polishing pad and contact area of the top polishing surface during polishing.

Abstract: The invention provides a method of forming porous polyurethane polishing pad that includes feeding liquid polyurethane onto a web sheet with a doctor blade while back tensioning the web. Coagulating liquid polyurethane onto the web sheet forms a two-layer substrate. The two-layer substrate has a porous matrix wherein the porous matrix has large pores extending upward from a base surface and open to an upper surface. Spring-arm sections connect lower and upper sections of the large pores.

Abstract: The method forms a porous polyurethane polishing pad by coagulating thermoplastic polyurethane to create a porous matrix having large pores extending upward from a base surface and open to an upper surface. The large pores are interconnected with small pores. Heating a press to temperature below or above the softening onset temperature of the thermoplastic polyurethane forms a series of pillows. Plastic deforming side walls of the pillow structures forms downwardly sloped side walls. The downwardly sloped side walls extend from all sides of the pillow structures. The large pores open to the downwardly sloped sidewalls are less vertical than the large pores open to the top polishing surface and are offset 10 to 60 degrees from the vertical direction.

Abstract: The porous polyurethane polishing pad includes a porous polyurethane matrix having large pores extending upward from a base surface and open to a polishing surface. A series of pillow structures is formed from the porous matrix that include the large pores and the small pores. The pillow structures have a downward surface extending from the top polishing surface for forming downwardly sloped side walls at an angle from 30 to 60 degrees from the polishing surface. The large pores open to the downwardly sloped sidewalls and are less vertical than the large pores. The large pores are offset 10 to 60 degrees from the vertical direction in a direction more orthogonal to the sloped sidewalls.

Abstract: The method forms a porous polyurethane polishing pad by coagulating thermoplastic polyurethane to create a porous matrix having large pores extending upward from a base surface and open to an upper surface. The large pores are interconnected with small pores. Heating a press to temperature below or above the softening onset temperature of the thermoplastic polyurethane forms a series of pillows. Plastic deforming side walls of the pillow structures forms downwardly sloped side walls. The downwardly sloped side walls extend from all sides of the pillow structures. The large pores open to the downwardly sloped sidewalls are less vertical than the large pores open to the top polishing surface and are offset 10 to 60 degrees from the vertical direction.

Abstract: The porous polyurethane polishing pad includes a porous polyurethane matrix having large pores extending upward from a base surface and open to a polishing surface. A series of pillow structures is formed from the porous matrix that include the large pores and the small pores. The pillow structures have a downward surface extending from the top polishing surface for forming downwardly sloped side walls at an angle from 30 to 60 degrees from the polishing surface. The large pores open to the downwardly sloped sidewalls and are less vertical than the large pores. The large pores are offset 10 to 60 degrees from the vertical direction in a direction more orthogonal to the sloped sidewalls.