I 1111111111111111 1111111111 11111 1111111111 1111111111 11111 lll111111111111111  USO 10082736B2  c12)  United States Patent  De Silva et al.  (IO)  Patent No.:  US 10,082,736 B2  Sep.25,2018  (45)  Date of Patent:  (54)  APPROACH TO LOWERING EXTREME  ULTRAVIOLET EXPOSURE DOSE FOR  INORGANIC HARDMASKS FOR EXTREME  ULTRAVIOLET PATTERNING  Grenville, et al., "Integrated Fab Process for Metal Oxide EUV  Photoresist", SPIE Advanced Lithography Conference 2015. Feb.  22, 2015. Proceedings vol. 9425. pp. 1-8.  (Continued)  G03F  71004  G03F  7116  G03F  7111  G03F  7109  G03F  7120  H0JL  211027  H0JL  2113213  B82Y  40100  (2006.01)  (2006.01)  (2006.01)  (2006.01)  (2006.01)  (2006.01)  (2006.01)  (2011.01)  (51)  Int. Cl.  (52)  U.S. Cl.  CPC ..............  G03F  71165  (2013.01);  B82Y  40100  (2013.01);  G03F  71094  (2013.01);  G03F  7111  (2013.01);  G03F  71168  (2013.01);  G03F  712004  (2013.01);  G03F  712037  (2013.01);  An extreme ultraviolet lithography pattern stack, including,  an inorganic hardmask layer, an under layer on the inorganic  hardmask layer, and a resist layer on the under layer, where  the inorganic hardmask layer, under layer, and resist layer  have a combined thickness in the range of about 8.5 nm to  about 70 nm.  (57)  ABSTRACT  20 Claims, 2 Drawing Sheets  Primary Examiner  - Amanda C Walke  (74)  Attorney, Agent, or Firm  - Tutunjian & Bitetto,  P.C.; Vazken Alexanian  OTHER PUBLICATIONS  (71)  Applicant:  INTERNATIONAL BUSINESS  MACHINES CORPORATION,  Armonk, NY (US)  (72)  Inventors:  Ekmini A. De Silva,  Slingerlands, NY  (US);  Karen E. Petrillo,  Voorheesville,  NY (US);  Indira P. Seshadri,  Troy, NY  (US)  (73)  Assignee:  International Business Machines  Corporation,  Armonk, NY (US)  ( *)  Notice:  Subject to any disclaimer, the term ofthis  patent is extended or adjusted under 35  U.S.C. 154(b) by 0 days.  (21)  Appl. No.:  15/406,327  (22)  Filed:  Jan. 13, 2017  (65)  Prior Publication Data  US 2018/0203355 Al  Jul. 19, 2018  H0JL 2110274  (2013.01);  H0JL 2110276  (2013.01);  H0JL 21/32139  (2013.01)  (58)  Field of Classification Search  CPC .......... G03F 7/004; G03F 7/2037; G03F 7/11;  G03F 7/165; G03F 7/094; H01L 21/0274;  H0lL 21/0276; H0lL 21/32139; B82Y  40/00  USPC ....... 430/270.1, 271.1, 273.1, 311, 322, 325,  430/329, 300, 331  See application file for complete search history.  (56)  References Cited  (Continued)  7,736,833 B2  8,257,910 Bl  8,658,050 B2  *  8,759,220 Bl  8,945,820 B2  6/2010 Angelopoulos et al.  9/2012 Guerrero et al.  2/2014 Engelmann ......... H0lL 21/0332  216/47  6/2014 Ogihara et al.  2/2015 Ogihara et al.  U.S. PATENT DOCUMENTS  210  FORM ORGANIC PLANARIZA.TION LAYER (OPL) ON  SUBSTRATE  220  FORM AN INORGANIC HARDMASK LAYER ON THE OPL  230  FORM AN UNDER LAYER ON THE INORGANIC  HARDMASK LAYER  240  FORM A RESlSTLAYER ON THE UNDER LAYER TO  FORM A PATTERN STACK  250  EXPOSE THE PATTERN STACK TO EUV LIGHT  (E.G., 13.5 nm) TO GENERATE ACID GROUPS  260  DEVELOP THE RESIST LAYER TO FORM A MASK  PATTERN AND BAKE THE PATTERN STACK  270  ETCH THE EXPOSED PORTIONS OF THE UNDER tAYER  ANO UNDERLYING HARDMASK 