content_image/913741.jpg content_image/913761.jpg content_image/913728.jpg content_image/913759.jpg content_image/913758.jpg content_image/913760.jpg
# c12) United States Patent Ohashi et al. 

# (54) SULFONIUM SALT, CHEMICALLY AMPLIFIED RESIST COMPOSITION, AND PATTERN FORMING PROCESS 

(71) Applicant: SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP) 

(72) Inventors: Masaki Ohashi, Joetsu (JP); Masahiro Fukushima, Joetsu (JP); Tomohiro Kobayashi, Joetsu (JP); Ryosuke Taniguchi, Joetsu (JP) 

(73) Assignee: SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP) 

( *) Notice: Subject to any disclaimer, the term ofthis patent is extended or adjusted under 35 U.S.C. 154(b) by O days. 

(21) Appl. No.: 14/481,324 

(22) Filed: Sep.9,2014 

## (65) Prior Publication Data 

US 2015/0086926 Al Mar. 26, 2015 

## (30) Foreign Application Priority Data 

Sep. 11, 2013 (JP) ................................. 2013-188086 

(51) Int. Cl. 

<img src='content_image/913741.jpg'>

(52) U.S. Cl. CPC ............. C07C 691753 (2013.01); C07C 591115 (2013.01); C07C 69/63 (2013.01); 

( 58) Field of Classification Search CPC .. C07C 69/753; C07C 69/635; C07C 69/757; G03F 7/004; G03F 7/2004; G03F 7/38 USPC ........ 560/117, 127; 430/270.1, 913,322,331 See application file for complete search history. 

(Continued) 

(Continued) 

<img src='content_image/913761.jpg'>

<img src='content_image/913728.jpg'>

# (IO) Patent No.: US 9,221,742 B2 

# (45) Date of Patent: Dec. 29, 2015 

## (56) References Cited 

<img src='content_image/913759.jpg'>

## FOREIGN PATENT DOCUMENTS 

<img src='content_image/913758.jpg'>

Machine translation of JP 2002-148790 (no date).* 

Primary Examiner - Amanda C Walke 

(74) Attorney, Agent, or Firm - Westerman, Hattori, Daniels & Adrian, LLP 

## (57) ABSTRACT 

A caboxylic acid sulfonium salt having formula (1) is pro› vided wherein R $^{0 }$is hydrogen or a monovalent hydrocarbon group, R 0 I and R $^{02 }$are hydrogen or a monovalent hydrocar› bon group, at least one ofR 0 , R 0 I and R $^{02 }$has a cyclic struc› ture, Lis a single bond or forms an ester, sulfonate, carbonate or carbamate bond with the vicinal oxygen atom, R 2 , R $^{3 }$and R 4 are monovalent hydrocarbon groups. The sulfonium salt functions as a quencher in a resist composition, enabling to form a pattern of good profile with minimal LWR, rectangu› larity, and high resolution. 

<img src='content_image/913760.jpg'>

US009221742B2 

## U.S. PATENT DOCUMENTS 

(Continued) 

(Continued) 

## OTHER PUBLICATIONS 

## 17 Claims, 14 Drawing Sheets 

