Chemical mechanical polishing pad and methods of making and using same

• US 8,535,119 B2
• Filed: 06/12/2012
• Issued: 09/17/2013
• Est. Priority Date: 08/15/2007
• Status: Expired due to Fees

• Current Assignee: Rohm and Haas Electronic Materials CMP Holdings, Inc.
• Original Assignee: Rohm and Haas Electronic Materials CMP Holdings, Inc.
• Inventors: Hreha, Richard D, Vining, Benjamin John, Palaparthi, Ravichandra V
• Primary Examiner(s): ROSE, ROBERT A
• Application Number:
  US13/494,575
• Publication Number:
  US 20120252324A1
• Time in Patent Office: 462 Days
• Field of Search: 451526-527, 451533-534, 451/548, 451/5, 451/8, 451/9, 451/41, 451/59, 512/93, 512/97, 512/98
• US Class Current: 451/41
• CPC Class Codes: B24B 37/24 characterised by the composition or properties of the pad materials
• CPC Class Codes: B24B 37/26 characterised by the shape of the lapping pad surface, e.g. grooved
• CPC Class Codes: B29C 61/06 Making preforms having internal stresses, e.g. plastic memory
• CPC Class Codes: B29C 70/66 the filler comprising hollow constituents, e.g. syntactic foam

Abstract

A method of making shape memory chemical mechanical polishing pads is provided, wherein the shape memory chemical mechanical polishing pads comprise a polishing layer in a densified state. Also provided is a method for using the shape memory chemical mechanical polishing pads to polish substrates.

Claims

1. A method for producing a shape memory chemical mechanical polishing pad, comprising:

providing a shape memory matrix material transformable between an original shape and a programmed shape;

preparing a polishing layer in an original state exhibiting an original thickness, OT, comprising the shape memory matrix material in the original shape;

subjecting the polishing layer to an external force;

setting the shape memory matrix material to the programmed shape to provide the polishing layer in a densified state, wherein the polishing layer exhibits a densified thickness, DT;

removing the external force;

wherein the DT is <

80% of the OT;

wherein the shape memory matrix material exhibits a >

70% reduction in storage modulus as the temperature of the shape memory matrix material is raised from (T_g−

20)°

C. to (T_g+20)°

C., wherein T_g is the glass transition temperature of the shape memory matrix material measured by dynamical mechanical analysis taking the inflection point in the storage modulus versus temperature curve as the T_g; and

,

wherein the polishing layer has a polishing surface adapted for polishing a substrate selected from at least one of a magnetic substrate, an optical substrate and a semiconductor substrate.

2. The method of claim 1, further comprising:

providing a plurality of microelements;

dispersing the plurality of microelements in the shape memory matrix material;

heating the polishing layer to a temperature, T, above the glass transition temperature, T_g, for the shape memory matrix material;

wherein the external force is an axial force which axially compresses the polishing layer to the densified thickness, DT, while maintaining the temperature of the polishing layer above the T_g of the shape memory matrix material; and

wherein the shape memory matrix material is set in the programmed shape by cooling the polishing layer to a temperature below the T_g of the shape memory matrix material, while maintaining the axial force.

3. The method of claim 1, wherein the reduction in storage modulus has a magnitude of >

800 MPa.

4. The method of claim 1, wherein the shape memory matrix material exhibits a T_g>

45°

C. to <

80°

C.

5. The method of claim 1, wherein the shape memory matrix material exhibits a >

90% reduction in storage modulus as the temperature of the shape memory matrix material is raised from (T_g−

10)°

C. to (T_g+10)°

C.; and

wherein the reduction in storage modulus has a magnitude of >

800 MPa.

6. The method of claim 1, wherein the shape memory matrix material comprises a reaction product of a mixture comprising glycerol propoxylate;

polycarbodiimide-modified diphenylmethane diisocyanate; and

at least one of polytetrahydrofuran and polycaprolactone.

7. The method of claim 1, wherein the shape memory matrix material comprises a reaction product of a mixture comprising a polyether-based, toluene diisocyanate terminated liquid urethane prepolymer;

and a 4,4′

-methylene-bis(2-chloroaniline).

8. A method of polishing a substrate, comprising:

providing a substrate selected from at least one of a magnetic substrate, an optical substrate and a semiconductor substrate;

providing a shape memory chemical mechanical polishing pad produced, using the method of claim 1; and

,

creating dynamic contact between a polishing surface of the polishing layer and the substrate to polish a surface of the substrate.

9. The method of claim 8, further comprising:

conditioning the polishing surface of the polishing layer by exposing at east a portion of the polishing layer proximate the polishing surface to an activating stimulus;

wherein the portion of the polishing layer proximate the polishing surface exposed to the activating stimulus transitions from the densified state to a recovered state.