Method for forming a striation reduced chemical mechanical polishing pad

• US 20060108701A1
• Filed: 11/23/2004
• Published: 05/25/2006
• Est. Priority Date: 11/23/2004
• Status: Abandoned Application

• Current Assignee: Rohm and Haas Electronic Materials CMP Holdings, Inc.
• Original Assignee: Rohm and Haas Electronic Materials CMP Holdings, Inc.
• Inventors: Saikin, Allan H.
• Application Number:
  US10/996,239
• Publication Number:
  US 20060108701A1
• Time in Patent Office: Days
• US Class Current: 264/7
• CPC Class Codes: B24B 37/205 provided with a window for inspecting the surface of the work being lapped
• CPC Class Codes: B24B 37/24 characterised by the composition or properties of the pad materials
• CPC Class Codes: B24D 18/00 Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
• CPC Class Codes: B29B 7/726 Measuring properties of mixture, e.g. temperature or density B29B7/724 takes precedence
• CPC Class Codes: B29B 7/7471 Mixers in which the mixing takes place at the inlet of a mould, e.g. mixing chambers situated in the mould opening
• CPC Class Codes: B29B 7/748 Plants B29B7/7433, B29B7/7485, B29B7/7495 take precedence
• CPC Class Codes: B29B 7/7485 with consecutive mixers, e.g. with premixing some of the components
• CPC Class Codes: B29B 7/749 with stirring means for the individual components before they are mixed together
• CPC Class Codes: B29B 7/90 Fillers or reinforcements , e.g. fibres

Abstract

The present invention provides a method of forming a chemical mechanical polishing pad, providing a tank with polymeric materials and a storage silo with microspheres. Further, the method includes the step of providing a curative storage tank with curing agents. Further, the method includes delivering the polymeric materials and the microspheres to a premix prep tank and forming a pre-mixture of the polymeric materials and the microspheres. The method further includes the step of recirculating the pre-mixture until a desired bulk density is reached. The method further provides the steps of delivering the pre-mixture to a premix run tank, forming a mixture of the pre-mixture and the curing agents, pouring the mixture into a mold and cutting the mold into the polishing pad.

Claims

1. A method of forming a chemical mechanical polishing pad, comprising:

providing a tank with polymeric materials;

providing a storage silo with microspheres;

providing a curative storage tank with curing agents;

delivering the polymeric materials and the microspheres to a premix prep tank;

forming a pre-mixture of the polymeric materials and the microspheres;

recirculating the pre-mixture until a desired bulk density is reached;

delivering the pre-mixture to a premix run tank;

forming a mixture of the pre-mixture and the curing agents;

pouring the mixture into a mold; and

cutting the mold into the polishing pad.

2. The method of claim 1 further comprising agitating the pre-mixture in the premix prep tank with an agitator.

3. The method of claim 1 further comprising degassing the premix prep tank.

4. The method of claim 1 further comprising providing an in-line densitometer in the recirculation loop for measuring the bulk density of the pre-mixture.

5. The method of claim 1 wherein the microsphere comprises polyvinyl alcohols, pectin, polyvinyl pyrrolidone, hydroxyethylcellulose, methylcellulose, hydropropylmethylcellulose, carboxymethylcellulose, hydroxypropylcellulose, polyacrylic acids, polyacrylamides, polyethylene glycols, polyhydroxyetheracrylites, starches, maleic acid copolymers, polyethylene oxide, polyurethanes, cyclodextrin, copolymers of acrylonitrile and vinylidene chloride and combinations thereof.

6. The method of claim 1 wherein the polymeric material comprises, polyurethanes, polycarbonates, polyesters, silicones, polyimides, polysulfone, polyvinyl chloride, polyacrylonitrile, polymethylmethacrylate, polyvinylidene fluoride, polyethylene terephthalate, polyetheretherketone, polyetherketone, polyetherimide, ethylvinyl acetate, polyvinyl butyrate, polyvinyl acetate, acrylonitrile butadiene styrene, fluorinated ethylene propylene and perfluoralkoxy polymers, and combinations thereof.

7. A method of forming a chemical mechanical polishing pad, comprising:

providing a first prepolymer storage tank with first polymeric materials;

providing a storage silo with microspheres;

providing a curative storage tank with curing agents;

providing at least a second prepolymer storage tank with second polymeric materials;

delivering the first polymeric materials from the first prepolymer storage tank and the microspheres to a premix prep tank;

forming a pre-mixture of the first polymeric materials and the microspheres;

recirculating the pre-mixture until a desired bulk density is reached;

delivering the pre-mixture to a premix run tank;

forming a mixture of the pre-mixture and the curing agents;

providing second polymeric materials to the mixture from the at least second prepolymer storage tank until a desired bulk density is reached;

pouring the mixture into a mold; and

cutting the mold into the polishing pad.

8. The method of claim 7 wherein the first and second polymeric materials are the same.

9. A method of forming a chemical mechanical polishing pad, comprising:

providing a prepolymer storage tank with polymeric materials;

providing a storage silo with microspheres;

providing a curative storage tank with curing agents;

delivering the polymeric materials and the microspheres to a premix run/prep tank;

forming a pre-mixture of the polymeric materials and the microspheres;

recirculating the pre-mixture until a desired bulk density is reached;

forming a mixture of the pre-mixture and the curing agents;

pouring the mixture into a mold; and

cutting the mold into the polishing pad.

10. The method of claim 9 comprising providing polymeric materials from another prepolymer storage tank to the mixture.