US010754248B2  (IO)  Patent No.:  US 10,754,248 B2  (45)  Date of Patent:  Aug. 25, 2020  c12)  United States Patent  Fujiwara et al.  (54)  SULFONIUM SALT, RESIST COMPOSITION,  AND PATTERNING PROCESS  (56)  References Cited  U.S. PATENT DOCUMENTS  FOREIGN PATENT DOCUMENTS  OTHER PUBLICATIONS  (57)  ABSTRACT  (65)  Prior Publication Data  (30)  Foreign Application Priority Data  (71)  Applicant:  SHIN-ETSU CHEMICAL CO., LTD.,  Tokyo (JP)  (73)  Assignee:  SHIN-ETSU CHEMICAL CO., LTD.,  Tokyo (JP)  (72)  Inventors:  Takayuki Fujiwara,  Joetsu (JP);  Ryo  Mitsui,  Joetsu (JP);  Kazuhiro  Katayama,  Joetsu (JP)  ( *)  Notice:  Subject to any disclaimer, the term ofthis  patent is extended or adjusted under 35  U.S.C. 154(b) by 7 days.  (21)  Appl. No.:  15/903,652  (22)  Filed:  Feb. 23, 2018  US 2018/0275516 Al  Sep. 27, 2018  Mar. 22, 2017  (JP) ................................... 2017-55526  (51)  Int. Cl.  (52)  U.S. Cl.  CPC ..............  G03F 71039  (2013.01);  C07C 69/00  (2013.01);  C07C 309112  (2013.01);  ( 58)  Field of Classification Search  CPC ...... G03F 7/039; G03F 7/2059; G03F 7/0397;  G03F 7/0045; G03F 7/029; G03F 7/0048;  (Continued)  (Continued)  (Continued)  G03F  71039  G03F  71029  (2006.01)  (2006.01)  The present invention provides a sulfonium salt capable of  providing a resist composition having few defects in pho› tolithography where a high energy beam is used as a light  source, and excellent in lithography performance by con› trolling acid diffusion.  The present invention was accomplished by a sulfonium salt  including an anion and a cation, the cation having a partial  structure represented by the following general formula (1),  except for a sulfonium salt having a cation represented by  the following general formula (1 ’),  Primary Examiner  - Cynthia Hamilton  (74)  Attorney, Agent, or Firm  - Oliff PLC  "Refractive index" Website Name: Encyclopaedia Britannica Pub› lisher: Encyclopaedia Britannica, Inc. Date Published: Dec. 28,  2018 URL: https://www.britannica.com/science/refractive-index Access  Date: Jul. 26, 2019, one page. (Year: 2018).*  (Continued)  (Continued)  (Continued)  Ra  Rfa  •-L!a_A!a++o-RXa  Rb  RJb  (1)  (Continued)  ORGANIC SOLVENT DEVELOPMENT  CN  JP  103787923 A  2003-066612 A  5/2014  3/2003  2003/0013039 Al  2006/0141383 Al  1/2003 Kobayashi et al.  6/2006 Miyamatsu et al. 