US 11,720,020 B2
Resist composition and patterning process
Jun Hatakeyama, Joetsu (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by Shin-Etsu Chemical Co., Ltd., Tokyo (JP)
Filed on Aug. 4, 2020, as Appl. No. 16/984,535.
Claims priority of application No. 2019-160863 (JP), filed on Sep. 4, 2019.
Prior Publication US 2021/0063879 A1, Mar. 4, 2021
Int. Cl. G03F 7/038 (2006.01); G03F 7/26 (2006.01); G03F 7/00 (2006.01); G03F 7/039 (2006.01)
CPC G03F 7/0382 (2013.01) [G03F 7/0002 (2013.01); G03F 7/0392 (2013.01); G03F 7/26 (2013.01)] 13 Claims
 
1. A resist composition comprising a base polymer and a salt, the salt consisting of an anion derived from a carboxylic acid having an iodized or brominated hydrocarbyl group exclusive of iodized or brominated aromatic ring and a cation derived from a 2,5,8,9-tetraaza-1-phosphabicyclo[3.3.3]undecane, biguanide or phosphazene compound wherein the salt has the formula (A):

OG Complex Work Unit Chemistry
wherein m and n are each independently 1, 2 or 3,
XB1 is iodine or bromine,
X1 is a single bond, ether bond, ester bond, amide bond, carbonyl group or carbonate group,
X2 is a single bond or a C1-C20 (m+1)-valent hydrocarbon group which may contain a heteroatom other than iodine and bromine,
R1 is a C1-C20 (n+1)-valent aliphatic hydrocarbon group which may contain at least one moiety selected from the group consisting of fluorine, chlorine, hydroxyl, carboxyl, C6-C12 aryl, ether bond, ester bond, carbonyl, amide bond, carbonate, urethane bond, and urea bond,
A+ is a cation having the formula (A)-1, (A)-2 or (A)-3:

OG Complex Work Unit Chemistry
wherein R11 to R13 are each independently a C1-C24 hydrocarbyl group which may contain a heteroatom,
R14 to R21 are each independently hydrogen or a C1-C24 hydrocarbyl group which may contain a heteroatom, a pair of R14 and R15, R15 and R16, R16 and R17, R17 and R18, R18 and R19, R19 and R20, or R20 and R21 may bond together to form a ring with the nitrogen atom to which they are attached, or the nitrogen atoms to which they are attached and intervening carbon atom, the ring optionally containing an ether bond,
R22 to R29 are each independently hydrogen or a C1-C24 hydrocarbyl group which may contain a heteroatom, a pair of R22 and R23, R23 and R24, R24 and R25, R25 and R26, R26 and R27, or R27 and R28 may bond together to form a ring with the nitrogen atom to which they are attached, or the nitrogen atoms to which they are attached and intervening phosphorus atom, a pair of R22 and R23, R24 and R25, R26 and R27, or R28 and R29 may bond together to form a group having the formula (A)-3-1, and R23 may be a group having the formula (A)-3-2 when R22 is hydrogen,

OG Complex Work Unit Chemistry
wherein R30 to R39 are each independently hydrogen or a C1-C24 hydrocarbyl group which may contain a heteroatom, a pair of R30 and R31, R31 and R32, R32 and R33, R33 and R34, R34 and R35, R36 and R37, or R38 and R39 may bond together to form a ring with the nitrogen atom to which they are attached, or the nitrogen atoms to which they are attached and intervening phosphorus atom, a pair of R30 and R31, R32 and R33, or R34 and R35 may bond together to form a group having the formula (A)-3-1,
the broken line designates a valence bond.