(10)  Patent No.:  US 8,968,979 B2  (45)  Date of Patent:  Mar.3,2015  c12)  United States Patent  Takemura et al.  (54)  POSITIVE RESIST COMPOSITION AND  PATTERNING PROCESS  (75)  Inventors:  Katsuya Takemura,  Joetsu (JP);  Keiichi  Masunaga,  Joetsu (JP);  Daisuke  Dornon,  Joetsu (JP);  Masayoshi  Sagehashi,  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 840 days.  (21)  Appl. No.:  12/623,155  (22)  Filed:  Nov. 20, 2009  (51)  Int. Cl.  (52)  U.S. Cl.  USPC ..................  430/270.1;  430/273.1; 430/275.1;  430/311; 430/326; 430/330; 430/905; 430/907;  430/910; 430/942  ( 58)  Field of Classification Search  None  See application file for complete search history.  OTHER PUBLICATIONS  (57)  ABSTRACT  16 Claims, No Drawings  FOREIGN PATENT DOCUMENTS  U.S. PATENT DOCUMENTS  (56)  References Cited  (30)  Foreign Application Priority Data  (65)  Prior Publication Data  G03F  71039  G03F  7111  G03F  7120  G03F  7130  G03F  7138  (2006.01)  (2006.01)  (2006.01)  (2006.01)  (2006.01)  5,650,483 A  6,312,867 Bl  6,329,125 B2  7,498,126 B2  7,569,326 B2  7,625,690 B2  7,887,988 B2  7/1997 Malik et al.  11/2001 Kinsho et al.  12/2001 Takechi et al.  3/2009 Ohsawa et al.  8/2009 Ohsawa et al.  12/2009 Mizutani et al.  2/2011 Mizutani et al.  2004/0214102 Al*  2005/0147920 Al*  2007/0218407 Al*  2008/0153030 Al  2009/0170029 Al *  10/2004 DiPietro et al. ............ 430/270.1  7/2005 Linetal. ....................... 430/311  9/2007 Mizutani et al. ........... 430/270.1  6/2008 Kobayashi et al.  7/2009 Choi et al. ................. 430/285.1  JP  JP  JP  JP  JP  JP  JP  7-325402  A  9-73173 A  9-90637  A  2000-171977 A  2000-336121  A  2002-372785  2004-85657  A  12/1995  3/1997  4/1997  6/2000  12/2000  * 12/2002  3/2004  JP  JP  JP  2004-292740  2006-178317 A  2007-140289 A  * 10/2004  7/2006  6/2007  (Continued)  Derwent English abstract of JP2004-292740 (2004). *  (Continued)  Primary Examiner  - Sin Lee  (74)  Attorney, Agent, or Firm  -Birch, Stewart, Kolasch &  Birch, LLP  A positive resist composition comprises a polymer compris› ing repeat units having formula (1) or (2).  (1)  (2)  Nov. 21, 2008  (JP) ................................. 2008-297828  US 2010/0129738Al  May 27, 2010  US008968979B2  denotes an aromatic hydrocarbon group, R$^{1 }$is H, methyl or  trifluoromethyl, R 2  is H, C$_{1}$-C$_{12 }$alkyl or aromatic hydrocar› bon group, R$^{3 }$is C$_{1 }$-C$_{12 }$alkyl, or R $^{2 }$and R$^{3 }$may bond together  to form a ring, and a is 1 or 2. When used in the ArF lithog› raphy, the resist composition exhibits high resolution. When  used in the EB image writing for mask processing, the resist  composition exhibits high resolution and sensitivity sufficient  to comply with high-accelerating-voltage EB irradiation, and  high etch resistance.  Herein 