US 11,940,728 B2
Molecular resist composition and patterning process
Masaki Ohashi, Joetsu (JP); Kazuhiro Katayama, Joetsu (JP); Masahiro Fukushima, Joetsu (JP); and Shun Kikuchi, Joetsu (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by Shin-Etsu Chemical Co., Ltd., Tokyo (JP)
Filed on Sep. 24, 2021, as Appl. No. 17/484,333.
Claims priority of application No. 2020-161573 (JP), filed on Sep. 28, 2020.
Prior Publication US 2022/0100089 A1, Mar. 31, 2022
Int. Cl. G03F 7/004 (2006.01); C07C 59/84 (2006.01); C07C 309/71 (2006.01); C07C 381/12 (2006.01)
CPC G03F 7/0045 (2013.01) [C07C 59/84 (2013.01); C07C 309/71 (2013.01); C07C 381/12 (2013.01); C07C 2601/14 (2017.05)] 8 Claims
OG exemplary drawing
 
1. A molecular resist composition comprising a sulfonium salt having the formula (1) and an organic solvent, wherein the molecular resist composition does not contain a base polymer,

OG Complex Work Unit Chemistry
wherein Ar1, Ar2 and Ar3 are each independently a C6-C20 aryl group in which some or all of the hydrogen atoms on its aromatic ring may be substituted by halogen or a C1-C20 hydrocarbyl group which may contain a heteroatom, at least one of Ar1, Ar2 and Ar3 is substituted with a group having the formula (1a), (1b) or (1c), any two of Ar1, Ar2 and Ar3 may bond together to form a ring with the sulfur atom to which they are attached,

OG Complex Work Unit Chemistry
wherein Ra1, Ra2 and Ra3 are each independently hydrogen or a C1-C10 hydrocarbyl group; Rb1, Rb2 and Rb3 are each independently a C1-C10 hydrocarbyl group, Rb1 and Rb2 may bond together to form a ring with the carbon atom to which they are attached; Rc1 and Rc2 are each independently hydrogen or a C1-C10 hydrocarbyl group, Rc3, Rc4 and Rc5 are each independently a C1-C10 hydrocarbyl group, Rc3 and Rc4 may bond together to form a ring with the carbon atom to which they are attached; the broken line designates a valence bond, and
X− is an anion, exclusive of a halide ion, BF4−, PF6−, SbF6− and anions having the following formulae (ex1) to (ex4):

OG Complex Work Unit Chemistry
wherein Rex1 is halogen or a C1-C40 hydrocarbyl group which may contain a heteroatom; Rex2, Rex3, Rex4, Rex5 and Rex6 are each independently fluorine or a C1-C40 hydrocarbyl group which may contain a heteroatom, Rex2 and Rex3 may bond together to form a ring with the carbon atoms to which they are attached and intervening atoms, Rex4 and Rex5 may bond together to form a ring with the carbon atoms to which they are attached and intervening atoms; Rex7 is halogen, hydroxy or a C1-C40 hydrocarbyl group which may contain a heteroatom; Rex8 and Rex9 are each independently fluorine or trifluoromethyl.