PAD FOR CHEMICAL MECHANICAL POLISHING
A polishing pad suitable for polishing at least one of semiconductor, optical, magnetic or electromechanical substrates comprises: a polishing layer including a polyurea having a soft phase and a hard phase, the soft phase being a copolymer of aliphatic fluorine-free species and a fluorinated aliphatic species, the polyurea being cured with a curing agent where the hard phase comprises crystallinity where the polyurea is characterized by a melting point of at least 230° C. and a ΔH f of at least 3 Joule/gram as determined by Dynamic Scanning Calorimetry of the polyurea
1 . A polishing pad suitable for polishing at least one of semiconductor, optical, magnetic
or electromechanical substrates comprising:
a polishing layer including a polyurea having a soft phase and a hard phase, the soft phase being a copolymer of aliphatic fluorine-free species and a fluorinated aliphatic species, the polyurea being cured with a curing agent where the hard phase comprises crystallinity where the polyurea is characterized by a melting point of at least 230° C. and a ΔH f of at least 3 Joule/gram as determined by Dynamic Scanning Calorimetry of the polyurea.
2 . The polishing pad of claim 1 wherein the polyurea of the polishing layer forms a matrix and the polishing layer further comprises gas or liquid-filled polymeric microelements dispersed in the matrix.
3 . The polishing pad of claim 1 wherein the curing agent comprises no less than 30 mole percent based on total moles of curing agent, of a curative of formula I:
wherein R 1 , R 2 , and R 3 are selected from H, halogen and alkyl groups of 1-3, provided at least one of R 1 , R 2 , and R 3 , are alkyl groups of 1-3 carbon atoms, and provided there is not more than one halogen per aromatic ring.
4 . The polishing pad of claim 3 wherein the curative of formula I is 4,4′-methylene-bis-(3-chloro-2,6-diethylaniline).
5 . The polishing pad of claim 3 wherein the curing agent further comprises one or more additional curatives selected from diethyltoluenediamine (DETDA); 3,5-dimethylthio-2,4-toluenediamine and isomers thereof, 3,5-diethyltoluene-2,4-diamine and isomers thereof (e.g., 3,5-diethyltoluene-2,6-diamine); 4,4′-bis-(sec-butylamino) diphenylmethane; 1,4-bis-(sec-butylamino)-benzene, 4,4′-methylene-bis-(2-chloroaniline) polytetramethyleneoxide-di-p-aminobenzoate; N,N-dialkyl diamino diphenyl methane; p,p′-methylene dianiline (MDA); m-phenylenediamine (MPDA); 4,4′-methylene-bis(2-chloroaniline) (MBOCA); 4,4′-methylene-bis-(2,6-diethylaniline) (MDEA); 4,4′-methylene-bis-(2,3-dichloroaniline) (MDCA); 4,4′-diamino-3,3′-diethyl-5,5′-dimethyl diphenylmethane, 2,2′,3,3-tetrachloro diamino diphenyl methane; trimethylene glycol di-p-aminobenzoate.
6 . The polishing pad of claim 1 wherein the copolymer of the soft phase has a structure containing fluorinated alkylene oxide and a non-fluorinated alkylene oxide,
wherein the mole ratio of fluorinated alkylene oxide to non-fluorinated alkylene oxide is less than 3.
7 . The polishing pad of claim 1 wherein the aliphatic fluorine-free polymer group is a polytetramethylene ether and wherein the hard phase comprises the reaction product of diisocyanate hard segments and a curative agent.
8 . The polishing pad of claim 1 wherein the polishing layer has a polishing surface comprising macrotexture.
9 . The polishing pad of claim 1 characterized in that removal rate at 120 rotations per minute at pressure of 346 hectoPascals is the same or higher than the removal rate at 275 hetcoPascals.
10 . The polishing pad of claim 1 characterized in that the polishing layer remains hydrophilic during polishing in shear conditions.