(IO)  Patent No.:  US 9,221,742 B2  (45)  Date of Patent:  Dec. 29, 2015  c12)  United States Patent  Ohashi et al.  (54)  SULFONIUM SALT, CHEMICALLY  AMPLIFIED RESIST COMPOSITION, AND  PATTERN FORMING PROCESS  US009221742B2  (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  (51)  Int. Cl.  (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)  G03F  71004  G03F  7138  (2006.01)  (2006.01)  (30)  Foreign Application Priority Data  (65)  Prior Publication Data  US 2015/0086926 Al  Mar. 26, 2015  Sep. 11, 2013  (JP) ................................. 2013-188086  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.  17 Claims, 14 Drawing Sheets  (57)  ABSTRACT  OTHER PUBLICATIONS  FOREIGN PATENT DOCUMENTS  U.S. PATENT DOCUMENTS  (56)  References Cited  (Continued)  (Continued)  Machine translation of JP 2002-148790 (no date).*  Primary Examiner  - Amanda C Walke  (74)  Attorney,  Agent,  or Firm  - Westerman,  Hattori,  Daniels  & Adrian, LLP  JP  JP  11-125907 A  11-327143 A  5/1999  11/1999  5,650,483 A  7/1997 Malik et al.  5,777,151 A *  7/1998 Crochemore ................... 560/61  (1) 