(45)  Date of Patent:  Oct. 30, 2012  (IO)  Patent No.:  US 8,298,748 B2  c12)  United States Patent  Seshimo et al.  (54)  POSITIVE RESIST COMPOSITION, METHOD  OF FORMING RESIST PATTERN, AND  POLYMERIC COMPOUND  (75)  Inventors:  Takehiro Seshimo,  Kawasaki (JP);  Yoshiyuki Utsumi,  Kawasaki (JP);  Yoshitaka Komuro,  Kawasaki (JP);  Takeyoshi Mimura,  Kawasaki (JP);  Daichi Takaki,  Kawasaki (JP)  (73)  Assignee:  Tokyo Ohka Kogyo Co., Ltd.,  Kawasaki-shi (JP)  ( *)  Notice:  Subject to any disclaimer, the term ofthis  patent is extended or adjusted under 35  U.S.C. 154(b) by 215 days.  (21)  Appl. No.:  12/781,540  (22)  Filed:  May 17, 2010  (51)  Int. Cl.  G03F 71004  (2006.01)  C0SF 228102  (2006.01)  (52)  U.S. Cl.  .....................  430/270.1;  430/905; 430/910;  430/921; 430/922; 526/286; 526/287; 526/288  (58)  Field of Classification Search  ............... 430/270.1,  430/905, 910, 921, 922; 526/286, 287, 288  See application file for complete search history.  (74)  Attorney, Agent, or Firm  -Knobbe Martens Olson &  BearLLP  6 Claims, No Drawings  (57)  ABSTRACT  OTHER PUBLICATIONS  FOREIGN PATENT DOCUMENTS  (56)  References Cited  U.S. PATENT DOCUMENTS  (65)  Prior Publication Data  (30)  Foreign Application Priority Data  US 2010/0297560Al  Nov. 25, 2010  May 20, 2009  (JP) ................................. 2009-122566  5,130,392  A  *  5,548,055  A  5,945,517 A  5,998,559  A  6,153,733  A  6,624,328 Bl  7,074,543 B2  7,396,960 B2  7,514,204 B2  *  7,858,287 B2  7/1992 Schwalm et al. ............. 526/288  8/1996 Narang et al.  8/ 1999 Nitta et al.  12/1999 Narang et al.  11/2000 Yukawa et al.  9/2003 Guerra et al.  7/2006 Iwai et al.  7/2008 Iwabuchi et al.  4/2009 Hatakeyama et al. ..... 430/270.1  12/2010 Watanabe et al. .......... 430/270.1  (Continued)  JP  H09-208554  8/1997  (Continued)  (Continued)  Kozawa, Takahiro et al., "Analysis of acid yield generated in chemi› cally amplified electron beam resist," J. Vac. Sci Technology. B, vol.  24, No. 6, pp. 3055 to 3060 (2006).  Primary Examiner  - John Chu  A positive resist composition including a base component  (A’) which exhibits increased solubility in an alkali develop› ing solution under action of acid and generates acid upon  exposure, the base component (A’) including a polymeric  compound (Al’) having a structural unit ( a5- l) represented  by general formula (a5-l), a structural unit (a0-1) represented  by general formula (a0-1) and a structural unit (a0-2) that  generates acid upon exposure, the structural unit (a0-2) con› taining a group represented by general formula (a0-2’)  (wherein  x- represents an anion moiety represented by one of  general formulas (1) to (5)).  (a5-1)  (a0-1)  (a0-2’)  (1)  0  x $^{0}$-Q 2 -0---fCF27;,S03  (2)  0  XIO-Q3-y!O_ N-S02-yll  0  A:  (3)  Y $^{12}$--’-CH .:...-so 0  \  2  Jq  3  (5)  US008298748B2 