US008114570B2  c12)  United States Patent  Ohsawa et al.  (IO)  Patent No.:  US 8,114,570 B2  (45)  Date of Patent:  Feb.14,2012  (54)  PHOTOACID GENERATOR, RESIST  COMPOSITION, AND PATTERNING  PROCESS  (75)  Inventors:  Youichi Ohsawa,  Joetsu (JP);  Takeshi  Kinsho,  Joetsu (JP);  Takeru Watanabe,  Joetsu (JP);  Koji Hasegawa,  Joetsu (JP);  Masaki Ohashi,  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 511 days.  (21)  Appl. No.:  12/410,357  (22)  Filed:  Mar. 24, 2009  (65)  Prior Publication Data  US 2009/0246694 Al  Oct. 1, 2009  (30)  Foreign Application Priority Data  Mar. 25, 2008  (JP) ................................. 2008-078049  (51)  Int. Cl.  G03F 71004  (2006.01)  G03F 7130  (2006.01)  C07D 307100  (2006.01)  C07C 309/03  (2006.01)  C07C 309/19  (2006.01)  (52)  U.S. Cl.  .....................  430/270.1;  430/326; 430/330;  430/91 O; 549/269; 549/300; 562/30; 562/111;  562/113  (58)  Field of Classification Search  ............... 430/270.1,  430/326, 330, 910; 549/269, 300; 562/30,  562/111, 113  See application file for complete search history.  (56)  References Cited  U.S. PATENT DOCUMENTS  5,635,332  A  5,705,702  A  5,714,625  A  6,063,953  A  6,136,502  A  6,261,738 Bl  6,306,555 Bl  6,312,867 Bl  6,329,125 B2  6,440,634 Bl  6,512,020 Bl  6,723,483 Bl  6,830,866 B2  6,849,374 B2  6,893,792 B2  7,288,359 B2  7,381,842 B2  7,399,577 B2  7,527,912 B2 *  7,927,780 B2 *  2004/0260031 Al  2007 /0003871 Al  2007 /0078269 Al  6/1997 Nakano et al.  l/ 1998 Osawa et al.  2/ 1998 Hada et al.  5/2000 Hada et al.  10/2000 Satoshi et  al.  7/2001 Asakura et al.  10/2001 Schulz et al.  11/2001 Kinsho et al.  12/2001 Takechi et al.  8/2002 Ohsawa et al.  1/2003 Asakura et  al.  4/2004 Oono et al.  12/2004 Kobayashi et al.  2/2005 Cameron et  al.  5/2005 Miya et al.  10/2007 Iwasawa et al.  6/2008 Kunimoto et al.  7/2008 Yamato et  al.  5/2009 Ohsawa et al. ............ 430/270.1  4/2011 Kawaue et al. ............ 430/270.1  12/2004 Takeda et al.  1/2007 Kodama et al.  4/2007 Harada et al.  16 Claims, 4 Drawing Sheets  2007/0122750 Al  5/2007 Yamaguchi et al.  2007/0218401 Al  9/2007 Ando eta!.  2007 /0231738 Al  10/2007 Kaneko et al.  2008/0318160 Al  12/2008 Ohsawa et al.  2009/0208871 Al *  8/2009 Kawaue et  al. ............ 430/285.1  2010/0099042 Al *  4/2010 Ohashi et al. .............. 430/270.1  FOREIGN PATENT DOCUMENTS  EP  0 473 547 Al  3/1992  JP  4-230645  A  8/1992  JP  7-25846  A  1/1995  JP  8-311018 A  11/1996  JP  9-15848 A  1/1997  JP  9-73173 A  3/1997  JP  9-90637  A  4/1997  JP  9-95479  A  4/1997  JP  9-208554  A  8/1997  JP  9-230588  A  9/1997  JP  9-301948 A  11/1997  JP  2906999 B2  6/1999  JP  11-190904 A  7 /1999  JP  2000-314956  A  11/2000  JP  2000-336121  A  12/2000  JP  2001-122850  A  5/2001  JP  2001-181221 A  7/2001  JP  2001-233842  A  8/2001  JP  2002-193887  A  7/2002  JP  2002-193925  A  7/2002  JP  2002-214774  A  7/2002  JP  2003-66612  A  3/2003  JP  2003-107706  A  4/2003  JP  2003-252855  A  9/2003  JP  2004-2252  A  1/2004  JP  2004-4561 A  1/2004  JP  2004-115630 A  4/2004  JP  2004-531749 A  10/2004  (Continued)  OTHER PUBLICATIONS  Choi et al., "Improved Lithographic Performance with Ultra-thin 193  nm Resist" Journal of Photopolymer Science and Technology, vol.  19, No. 3, 2006, pp. 313-318.  Lowe, "Synthesis of sulphonium salts" The chemistry of the  sulphortiunn group Part 1, John Wiley & Sons, 1981, Chapter 11, pp.  267-312.  Devoe et al., "Photochemistry and Photophysics of Onium Salts*"  Advances in Photochemistry, vol. 17, 1992 by John Wiley & Sons,  pp. 313-320.  (Continued)  Primary Examiner  - John Chu  (74)  Attorney, Agent, or Firm  -Birch, Stewart, Kolasch &  Birch, LLP  (57)  ABSTRACT  Photoacid generators generate sulfonic acids of formula (la)  upon exposure to high-energy radiation.  ROC(=O)R $^{1}$-----COOCH$_{2}$CF$_{2}$S0$_{3 }$ -w  (la)  RO is OH or C$_{1}$-C$_{20 }$organoxy, R 1  is a divalent C$_{1}$-C$_{20 }$ali› phatic group or forms a cyclic structure with RO. The photo› acid generators are compatible with resins and can control  acid diffusion and are thus suited for use in chemically ampli› fied resist compositions. 