US 11,772,230 B2
Formulations for high porosity chemical mechanical polishing pads with high hardness and CMP pads made therewith
Jing Ren, Hockessin, DE (US); Kwadwo Tettey, Bear, DE (US); and Bryan E. Barton, Lincoln University, PA (US)
Assigned to Rohm and Haas Electronic Materials CMP Holdings Inc., Newark, DE (US)
Filed by Rohm and Haas Electronic Materials CMP Holdings, Inc., Newark, DE (US)
Filed on Jan. 21, 2021, as Appl. No. 17/154,787.
Prior Publication US 2022/0226960 A1, Jul. 21, 2022
Int. Cl. B32B 3/24 (2006.01); C08G 18/18 (2006.01); C08G 18/48 (2006.01); C08J 9/30 (2006.01); B24B 37/24 (2012.01); C08G 18/12 (2006.01); C08G 18/76 (2006.01); C08G 18/32 (2006.01)
CPC B24B 37/24 (2013.01) [C08G 18/12 (2013.01); C08G 18/1825 (2013.01); C08G 18/3206 (2013.01); C08G 18/4854 (2013.01); C08G 18/7671 (2013.01); C08J 9/30 (2013.01); C08J 2201/022 (2013.01); C08J 2375/08 (2013.01)] 7 Claims
 
1. A chemical mechanical (CMP) polishing pad for polishing a substrate chosen from at least one of a magnetic substrate, an optical substrate and a semiconductor substrate, the polishing pad comprising a polishing layer adapted for polishing the substrate, the polishing layer comprising a thermoset polyurethane foam having roughly spherical hollow cells that are isolated or partially connected forming small isolated clusters, the polyurethane form is a product of an organic solvent free two-component reaction mixture comprising (i) a liquid aromatic isocyanate component comprising one or more aromatic diisocyanates or a linear aromatic isocyanate-terminated urethane prepolymer having an unreacted isocyanate (NCO) concentration of 18 to 47 wt. %, based on the total solids weight of the aromatic isocyanate component, (ii) a liquid polyol component, and (iii) one or more curatives selected from the group of amines having Formulas (I) and (II)

OG Complex Work Unit Chemistry
wherein each R1 and R2 are independently C1-C6 alkyl, C1-C4 alkyl substituted with one or more C1-C4 alkyl or one or more halogens, —(CR5R6)p—S—(CR5R6)q— or —(CR5R6)p—O—(CR5R6)q—; R3 is C1-C6 alkyl or C1-C4 alkyl substituted with one or more C1-C4 alkyl; each R4 is independently H or —R1—OH; each R5 and R6 are independently H or C1-C6 alkyl; each p and q are independently an integer from 1 through 5; and n is in the range of 1 to 4, wherein the reaction mixture comprises 55 to 75 wt. % of hard segment materials, based on the total weight of the reaction mixture, the total amount of the curatives (I) and/or (II) range from 9 to 26.8 wt %, based on the total weight of the reaction mixture, the CMP polishing layer has a unfilled Shore D (2 second) hardness of 57-77 or a filled Shore D (2 second) hardness of 18-50, and densities of 0.43 to 0.78 g/mL.