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CN-121986303-A - Radiation-sensitive composition, pattern forming method, and radiation-sensitive acid generator

CN121986303ACN 121986303 ACN121986303 ACN 121986303ACN-121986303-A

Abstract

The purpose of the present invention is to provide a radiation-sensitive composition capable of forming a resist film that can exhibit sufficient levels of sensitivity, LWR, pattern rectangularity, CDU, pattern circularity, and development defect performance, and a pattern formation method. In addition, the present invention also aims to provide a radioactive acid generator applicable to the radioactive composition. A radiation-sensitive composition comprising a polymer (A) containing a structural unit (I) having an acid dissociable group, a radiation-sensitive acid generator (B) represented by the following formula (1), and a solvent (E). [ formula 1] (in the formula (1), R 1 is a hydrogen atom, a nitro group, a hydroxyl group, a cyano group, a carboxyl group, a thiol group, a halogen atom or a monovalent organic group; when a plurality of R 1 are present, a plurality of R 1 are the same or different, R 2 is a monovalent organic group having 1 to 40 carbon atoms; M is an integer of 1 to 5; M + is a monovalent onium cation.)

Inventors

  • Abe Yudai
  • FURUICHI KOTA
  • Fuyuteru Kugawa
  • Dao Jianfu
  • NEMOTO KOICHI

Assignees

  • JSR株式会社

Dates

Publication Date
20260505
Application Date
20241213
Priority Date
20231221

Claims (11)

  1. 1. A radiation-sensitive composition comprising: a polymer (A) comprising a structural unit (I) having an acid dissociable group, A radioactive acid generator (B) represented by the following formula (1) Solvent (E). [ Chemical 1] (In the formula (1), R 1 is a hydrogen atom, a nitro group, a hydroxyl group, a cyano group, a carboxyl group, a thiol group, a halogen atom or a monovalent organic group. In the case where there are plural R 1 , plural R 1 are the same or different, respectively. R 2 is a monovalent organic group having 1 to 40 carbon atoms. M is an integer of 1 to 5. M + is a monovalent onium cation).
  2. 2. The radiation-sensitive composition according to claim 1, wherein the monovalent organic group represented by R 2 comprises at least one bond selected from the group consisting of an ester bond, an amide bond, an ether bond, a sulfonyl bond, a carbonyl bond, a thioether bond, and a carbonate bond.
  3. 3. The radiation-sensitive composition according to claim 1, wherein the monovalent organic group represented by R 2 comprises a cyclic structure.
  4. 4. The radiation-sensitive composition according to claim 1, wherein the content of the radiation-sensitive acid generator (B) is 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the polymer (a).
  5. 5. The radiation-sensitive composition according to claim 1, wherein the structural unit (I) having an acid dissociable group is represented by the following formula (2). [ Chemical 2] (In the formula (2), R α is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R A1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. R A2 and R A3 are each independently a monovalent chain hydrocarbon group having 1 to 20 carbon atoms or a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a divalent alicyclic group having 3 to 20 carbon atoms, wherein R A2 and R A3 are bonded to each other and are formed together with the bonded carbon atoms. M11 and m12 are each independently 0 or 1. Wherein, when m11 is 1, m12 is 1. When m11 is 0, L A1 represents a single bond or a divalent linking group, and when m11 is 1, L A1 is a divalent linking group).
  6. 6. The radiation-sensitive composition according to claim 1, wherein the polymer (a) further comprises a structural unit having a phenolic hydroxyl group.
  7. 7. The radiation-sensitive composition of claim 1, wherein the onium cation is a sulfonium cation or an iodonium cation.
  8. 8. The radiation-sensitive composition according to claim 1, further comprising an acid diffusion controlling agent (D).
  9. 9. A pattern forming method comprising: A step of forming a resist film by directly or indirectly applying the radiation-sensitive composition according to any one of claims 1 to 8 to a substrate; exposing the resist film to light, and And developing the exposed resist film.
  10. 10. The pattern forming method according to claim 9, wherein the exposure is performed by a KrF excimer laser, an ArF excimer laser, or an extreme ultraviolet ray.
  11. 11. A radioactive acid generator represented by the following formula (1). [ Chemical 3] (In the formula (1), R 1 is a hydrogen atom, a nitro group, a hydroxyl group, a cyano group, a carboxyl group, a thiol group, a halogen atom or a monovalent organic group. In the case where there are plural R 1 , plural R 1 are the same or different, respectively. R 2 is a monovalent organic group having 1 to 40 carbon atoms. M is an integer of 1 to 5. M + is a monovalent onium cation).

Description

Radiation-sensitive composition, pattern forming method, and radiation-sensitive acid generator Technical Field The present invention relates to a radiation-sensitive composition, a pattern forming method, and a radiation-sensitive acid generator. Background Photolithography using a resist composition is used for forming fine circuits of semiconductor elements. As a typical procedure, for example, a resist pattern is formed on a substrate by exposing a film of a resist composition to light through a mask pattern and irradiation with radiation to generate an acid, and by reacting the acid as a catalyst, a difference in solubility of a polymer to an alkali-based or organic-based developer is generated in an exposed portion and an unexposed portion. In the above-mentioned lithography technique, pattern miniaturization is advanced by using radiation having a short wavelength such as ArF excimer laser or by using a liquid immersion exposure method (liquid immersion lithography (Liquid Immersion Lithography)) in which exposure is further performed in a state in which a space between a lens of an exposure apparatus and a resist film is filled with a liquid medium. As a next-generation technique, lithography using radiation having a shorter wavelength such as electron beam, X-ray, and extreme ultraviolet (Extreme Ultraviolet, EUV) is also being studied. As the photoacid generator as a main component of the resist composition, a perfluoroalkylsulfonic acid capable of imparting a strong acid is often used in terms of improvement of sensitivity, resolution, and the like. On the other hand, in recent years, environmental awareness has been raised, and thus, a photoacid generator having a reduced fluorine atom content has been studied (see japanese patent application laid-open No. 2014-126767). Prior art literature Patent literature Patent document 1 Japanese patent laid-open publication No. 2014-126767 Disclosure of Invention Problems to be solved by the invention Even the photoacid generator having a reduced fluorine atom content is required to have performances equivalent to or higher than those of the conventional resists in terms of sensitivity, line width roughness (LINE WIDTH Roughness, LWR) indicating variations in line width or line width of resist patterns, pattern rectangularity, critical dimension uniformity (Critical Dimension Uniformity, CDU) as an index of uniformity of line width or aperture, pattern circularity, and development defect performance. The purpose of the present invention is to provide a radiation-sensitive composition capable of forming a resist film that can exhibit sufficient levels of sensitivity, LWR, pattern rectangularity, CDU, pattern circularity, and development defect performance, and a pattern formation method. In addition, the present invention also aims to provide a radioactive acid generator applicable to the radioactive composition. Technical means for solving the problems The present inventors have made diligent studies to solve the present problem, and as a result, have found that the above object can be achieved by adopting the following structure, and have completed the present invention. That is, the present invention relates in one embodiment to a radiation-sensitive composition comprising: a polymer (A) comprising a structural unit (I) having an acid dissociable group, A radioactive acid generator (B) represented by the following formula (1) Solvent (E). [ Chemical 1] (In the formula (1), R 1 is a hydrogen atom, a nitro group, a hydroxyl group, a cyano group, a carboxyl group, a thiol group, a halogen atom or a monovalent organic group, wherein when a plurality of R 1 exist, a plurality of R 1 are respectively the same or different; R 2 is a monovalent organic group with 1-40 carbon atoms; m is an integer of 1 to 5; M + is a monovalent onium cation) The radiation-sensitive composition can form a resist film exhibiting sensitivity, LWR, pattern rectangularity, CDU, pattern circularity and development defect performance at a sufficient level by containing the radiation-sensitive acid generator (B) represented by the formula (1). The reason for this is not limited to any theory, but is presumed as follows. The radioactive acid generator (B) has a difluoromethyl group at a carbon atom adjacent to a sulfonate anion, whereby it can maintain a sufficient acidity and be highly polarized as compared with a conventional radioactive acid generator having a large fluorine atom content. As a result, it is presumed that in the case of a positive resist, the solubility in an alkaline developer is improved by highly polarizing the radiation-sensitive acid generator (B), and various performances such as LWR and development defect performance can be improved. In the case of a negative resist, it is presumed that the effect of inhibiting dissolution of the developer is improved by the high polarization of the radiation-sensitive acid generator (B), and the effect of improving the shape of