content_image/915874.jpg content_image/915875.jpg
[0031] In a further aspect, the invention provides an amine compound having the formula (A’). 

<img src='content_image/915874.jpg'>

[0032] Herein R1, X, m and n are as defined above. The ring R 3 is a C$_{4}$ -C$_{6 }$ heterocycle formed with the nitrogen atom, which may contain an ether bond, thioether bond, -N(R 4 )-, carbonyl group or sulfonyl group, R 4 is hydro› gen, C$_{1 }$-C$_{6 }$ alkyl, C$_{2}$ -C$_{6 }$ alkenyl, C$_{2}$ -C$_{8 }$ acyl, C$_{7}$-C$_{20 }$aralkyl or C$_{1 }$-C$_{16 }$alkoxycarbonyl group. 

[0033] The iodized aromatic ring-containing amine com› pound is fully absorptive to EUV due to the inclusion of iodine, has a sensitizing effect, and is quite effective for suppressing acid diffusion by virtue of the large atomic weight of iodine. Since the compound is not photosensitive and is not decomposed in the exposed region, it has a high ability to control acid diffusion in the exposed region and is also effective for preventing a pattern from any film thick› ness loss by alkaline developer. Thus a resist composition having a high sensitivity, low LWR and improved CDU is designed. 

[0034] As used herein, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. The notation (Cn-Cm) means a group containing from n to m carbon atoms per group. As used herein, the term "iodized" compound means an iodine› substituted compound. In chemical formulae, Me stands for methyl, and Ac for acetyl. 

[0035] The abbreviations and acronyms have the follow› ing meaning. 

[0036] EB: electron beam 

[0037] EUV: extreme ultraviolet [0038] Mw: weight average molecular weight 

[0039] Mn: number average molecular weight 

[0040] Mw/Mn: molecular weight distribution or <lisper- sity 

[0041] GPC: gel permeation chromatography 

[0042] PEB: post-exposure bake 

[0043] PAG: photoacid generator 

[0044] LWR: line width roughness 

[0045] CDU: critical dimension uniformity 

## Resist Composition 

[0046] The resist composition of the invention is defined as comprising a base polymer and a quencher in the form of an iodized aromatic ring-containing amine compound. 

## Iodized Aromatic Ring-Containing Amine Compound 

[0047] The iodized aromatic ring-containing amine com› pound is an amine compound having an iodine-substituted aromatic ring bonded to the nitrogen atom via a C$_{1 }$-C$_{20 }$ 

## Advantageous Effects of Invention 

## DESCRIPTION OF EMBODIMENTS 

divalent hydrocarbon group which may contain at least one moiety selected from ester bond and ether bond. Preferably the amine compound has the formula (A). 

<img src='content_image/915875.jpg'>

[0048] In formula (A), R 1 is hydroxyl, a C$_{1}$-C$_{6 }$ alkyl group, C$_{1 }$-C$_{6 }$ alkoxy group, C$_{2}$-C$_{6 }$ acyloxy group, fluorine, chlorine, bromine, amino group, -NR$^{1}$A-C(=O)-R$^{1}$B, or-NR$^{1}$A----C(=O)-O-R$^{1}$B. R$^{1}$A is hydrogen ora C$_{1}$-C$_{6 }$ alkyl group.RIB is a C$_{1 }$-C$_{6 }$ alkyl, C$_{2}$-C$_{8 }$ alkenyl, C$_{6}$-C$_{12 }$aryl or C$_{7}$-C$_{13 }$ aralkyl group. 

[0049] The C$_{1 }$-C$_{6 }$ alkyl group may be straight, branched or cyclic, and examples thereof include methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert› butyl, cyclobutyl, n-pentyl, cyclopentyl, n-hexyl, and cyclo› hexyl. Examples of the alkyl moiety in the C$_{1}$-C$_{6 }$ alkoxy and C$_{2}$-C$_{6 }$ acyloxy groups are as exemplified above for the alkyl group. 

[0050] The C$_{2}$ -C$_{8 }$ alkenyl group may be straight, branched or cyclic, and examples thereof include vinyl, 1-propenyl, 2-propenyl, butenyl, hexenyl and cyclohexenyl. 

[0051] Suitable C$_{6}$-C$_{12 }$ aryl groups include phenyl, tolyl, xylyl, 1-naphthyl and 2-naphthyl. Suitable C$_{7}$-C$_{13 }$ aralkyl groups include benzyl and phenethyl. 1 

[0052] Among others, R is preferably fluorine, chlorine, bromine, hydroxyl, amino, C$_{1 }$-C$_{3 }$ alkyl, C$_{1 }$-C$_{3 }$ alkoxy, C$_{2}$-C$_{4 }$ acyloxy, -NR$^{1}$A----C(=O)-R$^{1}$B or -NR$^{1}$A----C(=O)› O-R IB. When n is 2 or more, a plurality of groups R $^{1 }$may be the same or different. 2 

[0053] R is hydrogen, nitro, or a C$_{1}$-C$_{20 }$ monovalent hydrocarbon group. The C$_{1 }$-C$_{20 }$ monovalent hydrocarbon group may be straight, branched or cyclic. Examples thereof include C$_{1 }$-C$_{20 }$ straight or branched alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec› butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-de› cyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hep› tadecyl, octadecyl, nonadecyl, and icosyl; C$_{3}$ -C$_{20 }$ monovalent saturated cycloaliphatic hydrocarbon groups such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropyl› methyl, 4-methylcyclohexyl, cyclohexylmethyl, norbomyl, and adamantyl; C$_{2}$-C$_{20 }$ straight or branched alkenyl groups such as vinyl, propenyl, butenyl and hexenyl; C$_{2}$-C$_{20 }$mon› ovalent unsaturated cycloaliphatic hydrocarbon groups such as cyclohexenyl and norbomenyl; C$_{2}$-C$_{20 }$ alkynyl groups such as ethynyl, propynyl, butynyl, 2-cyclohexylethynyl, and 2-phenylethynyl; CcC$_{20 }$ aryl groups such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphe› nyl, n-butylphenyl isobutylphenyl, sec-butylphenyl, tert› butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, and tert-butylnaphthyl; and C$_{7}$ -C$_{20 }$ aralkyl groups such as benzyl and phenethyl. The foregoing monovalent hydrocarbon groups may contain at least one moiety selected from hydroxyl, carboxyl, thiol, ether bond, ester bond, nitro, cyano, halogen and amino moiety. 

