1111111111111111 IIIIII IIIII 1111111111 11111 11111 lllll 111111111111111 11111 1111111111 11111111  US 20210033971Al  c19)  United States  c12)  Patent Application Publication  Hatakeyama  c10)  Pub. No.: US 2021/0033971 Al  (43)  Pub. Date:  Feb. 4, 2021  (54)  POSITIVE RESIST COMPOSITION AND  PATTERNING PROCESS  (71)  Applicant:  Shin-Etsu Chemical Co., Ltd.,  Tokyo  (JP)  (72)  Inventor:  Jun Hatakeyama,  Joetsu-shi (JP)  (73)  Assignee:  Shin-Etsu Chemical Co., Ltd.,  Tokyo  (JP)  (21)  Appl. No.:  16/942,981  (22)  Filed:  Jul. 30, 2020  (51)  Int. Cl.  (52)  U.S. Cl.  CPC ..........  G03F  71039  (2013.01);  G03F 7/70025  (2013.01);  C0SL  25114  (2013.01);  G03F  710045  (2013.01)  Publication Classification  (57)  ABSTRACT  (30)  Foreign Application Priority Data  Aug. 2, 2019  (JP) ................................. 2019-142916  A positive resist composition comprising a base polymer  comprising recurring units (a) of an ammonium salt of a  carboxylic acid having an iodized or brominated hydrocar› byl group and recurring units (bl) having an acid labile  group-substituted carboxyl group and/or recurring units (b2)  having an acid labile group-substituted phenolic hydroxyl  group has a high sensitivity and resolution and forms a  pattern of good profile with reduced edge roughness and  improved dimensional uniformity.  G03F  71039  G03F  71004  C0SL  25114  (2006.01)  (2006.01)  (2006.01) 