Monomer, polymer, resist composition, and patterning process
A monomer (1) is prepared by reacting a compound (9) with a base or metal to form a metal enolate reagent, and reacting the metal enolate reagent with an acyloxyketone compound (8). A polymer derived from the monomer is used as base resin to formulate a resist composition, which is shelf stable and displays a high dissolution contrast, controlled acid diffusion and low roughness in forming positive pattern via alkaline development and in forming negative pattern via organic solvent development.
1. A method for preparing a monomer having the general formula (1), comprising the steps of reacting a compound having the general formula (9) with a base or a metal selected from Group 1A, 2A and 2B metals to form a metal enolate reagent, and reacting the metal enolate reagent with an acyloxyketone compound having the general formula (8):
wherein R 1 is hydrogen, methyl or trifluoromethyl,
R 2 is hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom,
R 3 and R 4 are each independently hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom, R 3 and R 4 may bond together to form a ring with the carbon atom to which they are attached,
R 5 and R 6 are each independently hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom, R 5 and R 6 may bond together to form a ring with the carbon atom to which they are attached,
R 7 and R 8 are each independently hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom, R 7 and R 8 may bond together to form a ring with the carbon atom to which they are attached,
X 1 is a C 1 -C 10 alkylene group which may have an ether, ester, lactone ring or hydroxyl, or a C 6 -C 10 arylene group,
m is 0 or 1, in case of m=0, R 2 may bond with R 5 or R 6 to form a ring with the carbon atoms to which they are attached, in case of m=1, R 2 may bond with R 7 or R 8 to form a ring with the carbon atoms to which they are attached,
k 1 is 0 or 1,
X c is hydrogen or halogen, and
R a is a straight or branched C 1 -C 10 monovalent hydrocarbon group.
2. A method for preparing a monomer having the general formula (1), comprising the steps of reacting a compound having the general formula (9) with a base or a metal selected from Group 1A, 2A and 2B metals to form a metal enolate reagent, reacting the metal enolate reagent with an acyloxyketone compound having the general formula (8), isolating the resulting intermediate having the general formula (12), and lactonizing the intermediate:
wherein R 1 is hydrogen, methyl or trifluoromethyl,
R 2 is hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom,
R 3 and R 4 are each independently hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom, R 3 and R 4 may bond together to form a ring with the carbon atom to which they are attached,
R 5 and R 6 are each independently hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom, R 5 and R 6 may bond together to form a ring with the carbon atom to which they are attached,
R 7 and R 8 are each independently hydrogen or a straight, branched or cyclic C 1 -C 10 monovalent hydrocarbon group which may contain a heteroatom, R 7 and R 8 may bond together to form a ring with the carbon atom to which they are attached,
X 1 is a C 1 -C 10 alkylene group which may have an ether, ester, lactone ring or hydroxyl, or a C 6 -C 10 arylene group,
m is 0 or 1, in case of m=0, R 2 may bond with R 5 or R 6 to form a ring with the carbon atoms to which they are attached, in case of m=1, R 2 may bond with R 7 or R 8 to form a ring with the carbon atoms to which they are attached,
k 1 is 0 or 1,
X c is hydrogen or halogen, and
R a is a straight or branched C 1 -C 10 monovalent hydrocarbon group.
3. The method of claim 1 wherein the acyloxyketone compound having formula (8) is prepared by reaction of a haloketone compound having the general formula (4) with a carboxylic acid salt compound having the general formula (5):
wherein R 1 , R 2 , R 5 , R 6 , R 7 , R 8 , X 1 , m and k 1 are as defined above, X a is halogen, and M a is Li, Na, K, Mg 1/2 , Ca 1/2 or substituted or unsubstituted ammonium.
4. The method of claim 1 wherein the acyloxyketone compound having formula (8) is prepared by reaction of an alcohol compound having the general formula (6) with an esterifying agent having the general formula (7):
wherein R 1 , R 2 , R 5 , R 6 , R 7 , R 8 , X 1 , m and k 1 are as defined above, X b is halogen, hydroxyl or —OR b , and R b is methyl, ethyl or a group having the formula (11):
wherein R 1 , X 1 and k 1 are as defined above, and the broken line denotes a valence bond.