Method of making composite polishing layer for chemical mechanical polishing pad

Patent metadata

Field	Value
Publication number	US-2016375552-A1
Application number	US-201514751410-A
Country	US
Kind code	A1
Filing date	Jun 26, 2015
Priority date	Jun 26, 2015
Publication date	Dec 29, 2016
Grant date	—

Abstract

A method of forming a chemical mechanical polishing pad composite polishing layer is provided, including: providing a first polishing layer component of a first continuous non-fugitive polymeric phase having a plurality of periodic recesses; discharging a combination toward the first polishing layer component at a velocity of 10 to 300 msec, filling the plurality of periodic recesses with the combination; allowing the combination to solidify in the plurality of periodic recesses forming a second non-fugitive polymeric phase giving a composite structure; and, deriving the chemical mechanical polishing pad composite polishing layer from the composite structure, wherein the chemical mechanical polishing pad composite polishing layer has a polishing surface on the polishing side of the first polishing layer component; and wherein the polishing surface is adapted for polishing a substrate.

First claim

We claim:

1 . A method of forming a chemical mechanical polishing pad composite polishing layer, comprising:
providing a first polishing layer component of the chemical mechanical polishing pad composite polishing layer;
wherein the first polishing layer component has a polishing side, a base surface, a plurality of periodic recesses and an average first component thickness, T 1-avg , measured normal to the polishing side from the base surface to the polishing side;
wherein the first polishing layer component comprises a first continuous non-fugitive polymeric phase;
wherein the plurality of periodic recesses have an average recess depth, D avg , measured normal to the polishing side from the polishing side toward the base surface, wherein the average recess depth, D avg , is less than the average first component thickness, T 1-avg ;
wherein the first continuous non-fugitive polymeric phase is a reaction product of a first continuous phase isocyanate-terminated urethane prepolymer having 8 to 12 wt % unreacted NCO groups and a first continuous phase curative;
providing a poly side (P) liquid component, comprising at least one of a (P) side polyol, a (P) side polyamine and a (P) side alcohol amine; providing an iso side (I) liquid component, comprising at least one polyfunctional isocyanate; providing a pressurized gas; providing an axial mixing device having an internal cylindrical chamber;
wherein the internal cylindrical chamber has a closed end, an open end, an axis of symmetry, at least one (P) side liquid feed port that opens into the internal cylindrical chamber, at least one (I) side liquid feed port that opens into the internal cylindrical chamber, and at least one tangential pressurized gas feed port that opens into the internal cylindrical chamber;
wherein the closed end and the open end are perpendicular to the axis of symmetry;
wherein the at least one (P) side liquid feed port and the at least one (I) side liquid feed port are arranged along a circumference of the internal cylindrical chamber proximate the closed end;
wherein the at least one tangential pressurized gas feed port is arranged along the circumference of the internal cylindrical chamber downstream of the at least one (P) side liquid feed port and the at least one (I) side liquid feed port from the closed end;
wherein the poly side (P) liquid component is introduced into the internal cylindrical chamber through the at least one (P) side liquid feed port at a (P) side charge pressure of 6,895 to 27,600 kPa; wherein the iso side (I) liquid component is introduced into the internal cylindrical chamber through the at least one (I) side liquid feed port at an (I) side charge pressure of 6,895 to 27,600 kPa; wherein a combined mass flow rate of the poly side (P) liquid component and the iso side (I) liquid component to the internal cylindrical chamber is 6 to 50 g/s; wherein the poly side (P) liquid component, the iso side (I) liquid component and the pressurized gas are intermixed within the internal cylindrical chamber to form a combination; wherein the pressurized gas is introduced into the internal cylindrical chamber through the at least one tangential pressurized gas feed port with a supply pressure of 150 to 1,500 kPa; wherein an inlet velocity into the internal cylindrical chamber of the pressurized gas is 90 to 600 m/s; discharging the combination from the open end of the internal cylindrical chamber toward the polishing side of the first polishing layer component at a velocity of 10 to 300 msec, filling the plurality of periodic recesses with the combination; allowing the combination to solidify as a second polishing layer component in the plurality of periodic recesses to form a composite structure; wherein the second polishing layer component is a second non-fugitive polymeric phase; and, deriving the chemical mechanical polishing pad composite polishing layer from the composite structure, wherein the chemical mechanical polishing pad composite polishing layer has a polishing surface on the polishing side of the first polishing layer component; and wherein the polishing surface is adapted for polishing a substrate.

2 . The method of claim 1 , further comprising:
machining the composite structure to derive the chemical mechanical polishing pad composite polishing layer; wherein the chemical mechanical polishing pad composite polishing layer so derived has an average composite polishing layer thickness, T P-avg , measured normal to the polishing surface from the base surface to the polishing surface; wherein the average first component thickness, T 1-avg , equals the average composite polishing layer thickness, T P-avg ; wherein the second non-fugitive polymeric phase occupying the plurality of periodic recesses has an average height, H avg , measured normal to the polishing surface from the base surface toward the polishing surface; and, wherein an absolute value of a difference, ΔS, between the average composite polishing layer thickness, T P-avg , and the average height, H avg , is ≦0.5 μm.

3 . The method of claim 2 , further comprising:
forming at least one groove in the polishing surface.

4 . The method of claim 1 , wherein providing the first polishing layer component, further comprises:
providing a mold having a floor and a surrounding wall, wherein the floor and the surrounding wall define a mold cavity; providing the first continuous phase isocyanate-terminated urethane prepolymer having 8 to 12 wt % unreacted NCO groups, the first continuous phase curative and, optionally, a plurality of hollow core polymeric materials; mixing the first continuous phase isocyanate-terminated urethane prepolymer and the first continuous phase curative to form a mixture; pouring the mixture into the mold cavity; allowing the mixture to solidify into a cake of the first continuous non-fugitive polymeric phase; deriving a sheet from the cake; forming the plurality of periodic recesses in the sheet to provide the first polishing layer component.

5 . The method of claim 4 , wherein the plurality of hollow core polymeric materials is incorporated in the first continuous non-fugitive polymeric phase at 1 to 58 vol %.

6 . The method of claim 1 , wherein the poly side (P) liquid component comprises 25 to 95 wt % of a (P) side polyol; wherein the (P) side polyol is a high molecular weight polyether polyol; wherein the high molecular weight polyether polyol has a number average molecular weight, M N , of 2,500 to 100,000 and an average of 4 to 8 hydroxyl groups per molecule.

7 . The method of claim 1 , wherein the iso side (I) liquid component comprises a polyfunctional isocyanate having an average of two reactive isocyanate groups per molecule.

8 . The method of claim 1 , wherein the pressurized gas is selected from the group consisting of: CO 2 , N 2 , air and argon.

9 . The method of claim 1 , wherein the internal cylindrical chamber has a circular cross section in a plane perpendicular to the axis of symmetry of the internal cylindrical chamber; wherein the open end of the internal cylindrical chamber has a circular opening perpendicular to the axis of symmetry of the internal cylindrical chamber; wherein the circular opening is concentric with the circular cross section; and, wherein the circular opening has an inner diameter of 2.5 to 6 mm.

10 . The method of claim 1 , wherein the polishing surface is adapted for polishing a semiconductor wafer.

Assignees

• Rohm & Haas Elect Materials Cmp Holdings Inc
• Dow Global Technologies Llc

Inventors

• Qian Bainian
• Brugarolas Brufau Teresa
• Kozhukh Julia
• Veneziale David Michael
• Tong Yuhua
• Lugo Diego
• Jacob George C
• Miller Jeffrey B
• Tran Tony Quan
• Stack Marc R
• Wank Andrew
• Hendron Jeffrey James

Classifications

• B24B37/24

  characterised by the composition or properties of the pad materials · CPC title

• B24B37/22

  characterised by a multi-layered structure · CPC title

• B24D18/00 Primary

  Manufacture of grinding tools {or other grinding devices}, e.g. wheels, not otherwise provided for · CPC title