Polymer, chemically amplified resist composition and patterning process

Patent metadata

Field	Value
Publication number	US-12032289-B2
Application number	US-202017022368-A
Country	US
Kind code	B2
Filing date	Sep 16, 2020
Priority date	Sep 26, 2019
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

A polymer comprising recurring units having a multiple bond-containing acid labile group, recurring units having a phenolic hydroxyl group, and recurring units adapted to generate an acid upon exposure is used to formulate a resist composition, which exhibits a high sensitivity, low LWR and improved CDU when processed by lithography using EUV of wavelength 13.5 nm.

First claim

The invention claimed is:

1. A resist composition comprising a polymer consisting of recurring units having an acid labile group containing a multiple bond, recurring units having a phenolic hydroxyl group, recurring units adapted to generate an acid upon exposure, and recurring units having the formula (d1) or (d2),
wherein the recurring units having an acid labile group containing a multiple bond have the formula (a):

wherein R A is each independently hydrogen, fluorine, methyl or trifluoromethyl,
X 1 is a single bond, phenylene group, naphthylene group or (backbone)-C(═O)—O—X 11 —, X 11 is a C 1 -C 10 aliphatic hydrocarbylene group which may contain a hydroxyl moiety, ether bond, ester bond or lactone ring, or a phenylene or naphthylene group,
A L1 is an acid labile group having the formula (a1) or (a2):

wherein R 1 to R 8 are each independently hydrogen or a C 1 -C 20 hydrocarbyl group which may contain a heteroatom, with the proviso that not both R 1 and R 2 are hydrogen at the same time and not both R 6 and R 7 are hydrogen at the same time, a pair of R 1 and R 2 , R 1 and R 3 , R 3 and R 4 , R 4 and R 5 , R 6 and R 7 , or R 6 and R 8 may bond together to form an aliphatic ring with the carbon atom(s) to which they are attached or the carbon atoms to which they are attached and the intervening carbon atom,
wherein the recurring units adapted to generate an acid upon exposure have the formula (c1), (c2) or (c3):

wherein R A is each independently hydrogen, fluorine, methyl or trifluoromethyl,
Z 1 is a single bond or phenylene group,
Z 2 is a single bond, —C(═O)—O—Z 21 —, —C(═O)—NH—Z 21 — or —O—Z 21 —, —Z 21 is a C 1 -C 6 aliphatic hydrocarbylene group, phenylene group or a divalent group obtained from combination thereof, which may contain a carbonyl moiety, ester bond, ether bond or hydroxyl moiety,
Z 3 is a single bond, phenylene, naphthylene, or (backbone)-C(═O)—O—Z 31 —, Z 31 is a C 1 -C 10 aliphatic hydrocarbylene group which may contain a hydroxyl moiety, ether bond, ester bond or lactone ring, or phenylene or naphthylene group,
Z 4 is a single bond or —Z 41 —C(═O)—O—, Z 41 is a C 1 -C 20 hydrocarbylene group which may contain a heteroatom,
Z 5 is a single bond, methylene, ethylene, phenylene, fluorinated phenylene, —C(═O)—O—Z 51 —, —C(═O)—NH—Z 51 — or —O—Z 51 —, Z 51 is a C 1 -C 6 aliphatic hydrocarbylene group or phenylene group, which may contain a carbonyl moiety, ester bond, ether bond or hydroxyl moiety,
R 21 and R 22 are each independently a C 1 -C 20 hydrocarbyl group which may contain a heteroatom, R 21 and R 22 may bond together to form a ring with the sulfur atom to which they are attached,
L 1 is a single bond, ether bond, ester bond, carbonyl group, sulfonic acid ester bond, carbonate bond or carbamate bond,
Rf 1 and Rf 2 are each independently fluorine or a C 1 -C 6 fluoroalkyl group,
Rf 3 and Rf 4 are each independently hydrogen, fluorine or a C 1 -C 6 fluoroalkyl group,
M − is a non-nucleophilic counter ion,
A + is an onium cation, and
k is an integer of 0 to 3,
wherein A + is a cation having the formula (c4) or (c5):

wherein R 31 , R 32 and R 33 are each independently a C 1 -C 20 hydrocarbyl group which may contain a heteroatom, R 31 and R 32 may bond together to form a ring with the sulfur atom to which they are attached, R 34 and R 35 are each independently a C 1 -C 20 hydrocarbyl group which may contain a heteroatom,

wherein R A is each independently hydrogen, fluorine, methyl or trifluoromethyl,
X 1 is a single bond, phenylene group, naphthylene group or (backbone)-C(═O)—O—X 11 —, X 11 is a C 1 -C 10 aliphatic hydrocarbylene group which may contain a hydroxyl moiety, ether bond, ester bond or lactone ring, or a phenylene or naphthylene group,
Y 1 is a single bond or (backbone)-C(═O)—O—,
A L2 and A L3 are each independently an acid labile group free of multiple bond,
R 41 is halogen, cyano, a C 1 -C 20 hydrocarbyl group which may contain a heteroatom, C 1 -C 20 hydrocarbyloxy group which may contain a heteroatom, C 2 -C 20 hydrocarbylcarbonyl group which may contain a heteroatom, C 2 -C 20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or C 2 -C 20 hydrocarbyloxycarbonyl group which may contain a heteroatom, and
p is an integer of 0 to 4.

2. The resist composition of claim 1 wherein the recurring units having a phenolic hydroxyl group have the formula (b):

wherein R A is each independently hydrogen, fluorine, methyl or trifluoromethyl, Y′ is a single bond or (backbone)-C(═O)—O—, R 11 is halogen, cyano, a C 1 -C 20 hydrocarbyl group which may contain a heteroatom, C 1 -C 20 hydrocarbyloxy group which may contain a heteroatom, C 2 -C 20 hydrocarbylcarbonyl group which may contain a heteroatom, C 2 -C 20 hydrocarbylcarbonyloxy group which may contain a heteroatom, or C 2 -C 20 hydrocarbyloxycarbonyl group which may contain a heteroatom, m is an integer of 1 to 4, n is an integer of 0 to 4, and 1≤m+n≤5.

3. The resist composition of claim 1 , further comprising an organic solvent.

4. The resist composition of claim 1 , further comprising a photoacid generator.

5. The resist composition of claim 1 , further comprising a quencher.

6. The resist composition of claim 1 , further comprising a surfactant which is insoluble or substantially insoluble in water and soluble in an alkaline developer and/or a surfactant which is insoluble or substantially insoluble in water and an alkaline developer.

7. A process for forming a pattern comprising the steps of applying the resist composition of claim 1 to a substrate to form a resist film thereon, exposing the resist film to high-energy radiation, and developing the exposed resist film in a developer.

8. The process of claim 7 wherein the high-energy radiation is i-line, KrF excimer laser, ArF excimer laser, EB, or EUV of wavelength 3 to 15 nm.

9. The resist composition of claim 1 wherein the fraction of recurring units (a), (b), (c), (d1) and (d2) is 0<a<1.0, 0<b<1.0, 0<c<1.0, 0≤d1≤0.8, 0≤d2≤0.8, d1+d2>0 and a+b+c+d1+d2=1.0.

10. The resist composition of claim 9 wherein the fraction of recurring units (a), (b) and (c) is 0.05≤a≤0.9, 0.09≤b≤0.55, and 0.01≤c≤0.4.

Assignees

• Shinetsu Chemical Co

Inventors

• Fukushima Masahiro
• Sagehashi Masayoshi
• Ono Emiko

Classifications

• G03F7/039

  Macromolecular compounds which are photodegradable, e.g. positive electron resists (G03F7/075 takes precedence; macromolecular quinonediazides G03F7/023) · CPC title

• C08F220/283

  and containing one or more carboxylic moiety in the chain, e.g. acetoacetoxyethyl(meth)acrylate · CPC title

• C09D125/18

  Homopolymers or copolymers of aromatic monomers containing elements other than carbon and hydrogen · CPC title

• C08F212/24

  Phenols or alcohols · CPC title

• C09D133/14

  of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen · CPC title