US 9,810,983 B2
Polymer, chemically amplified positive resist composition and patterning process
Jun Hatakeyama, Joetsu (JP); Koji Hasegawa, Joetsu (JP); and Masayoshi Sagehashi, Joetsu (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed on Jun. 17, 2016, as Appl. No. 15/185,195.
Claims priority of application No. 2015-124100 (JP), filed on Jun. 19, 2015.
Prior Publication US 2016/0370702 A1, Dec. 22, 2016
Int. Cl. G03F 7/039 (2006.01); C08F 220/16 (2006.01); C08F 224/00 (2006.01); G03F 7/32 (2006.01); C08F 222/20 (2006.01); G03F 7/004 (2006.01); G03F 7/085 (2006.01)
CPC G03F 7/0392 (2013.01) [C08F 220/16 (2013.01); C08F 222/20 (2013.01); C08F 224/00 (2013.01); G03F 7/0045 (2013.01); G03F 7/0046 (2013.01); G03F 7/0395 (2013.01); G03F 7/0397 (2013.01); G03F 7/085 (2013.01)] 13 Claims
 
1. A polymer comprising recurring units (a1) having the general formula (1):

OG Complex Work Unit Drawing
wherein R1 is —C(═O)—R4, —O—C(═O)—R4 or —C(═O)—O—R4, R2 is hydrogen or methyl, R3 is an acid labile group, and R4 is a straight or branched C1-C4 alkyl group or C2-C4 alkenyl group, the polymer having a weight average molecular weight of 1,000 to 500,000.
 
9. A chemically amplified positive resist composition comprising the polymer of claim 1, and an organic solvent.
 
12. A pattern forming process comprising the steps of coating the positive resist composition of claim 9 onto a substrate, baking the coating to form a resist film, exposing the resist film to high-energy radiation, and developing the exposed resist film in a developer.
 
13. The process of claim 12 wherein the high-energy radiation is KrF excimer laser, ArF excimer laser, soft X-ray of wavelength 3 to 15 nm, or electron beam.