US 11,720,021 B2
Positive resist composition and patterning process
Jun Hatakeyama, Joetsu (JP); and Masahiro Fukushima, Joetsu (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by Shin-Etsu Chemical Co., Ltd., Tokyo (JP)
Filed on Oct. 2, 2020, as Appl. No. 17/62,048.
Claims priority of application No. 2019-191782 (JP), filed on Oct. 21, 2019.
Prior Publication US 2021/0116808 A1, Apr. 22, 2021
Int. Cl. G03F 7/004 (2006.01); G03F 7/039 (2006.01); C08F 212/14 (2006.01); C08F 220/18 (2006.01); C08F 220/30 (2006.01); C08F 20/52 (2006.01); C08F 220/56 (2006.01)
CPC G03F 7/039 (2013.01) [C08F 20/52 (2013.01); C08F 212/24 (2020.02); C08F 220/1808 (2020.02); C08F 220/30 (2013.01); C08F 220/303 (2020.02); C08F 220/56 (2013.01)] 11 Claims
 
1. A positive resist composition comprising a base polymer comprising recurring units (a) containing an imide group having an iodine-substituted aromatic group bonded thereto, and recurring units of at least one type selected from recurring units (b1) having a carboxyl group whose hydrogen is substituted by an acid labile group and recurring units (b2) having a phenolic hydroxyl group whose hydrogen is substituted by an acid labile group,
wherein the recurring units (a) have the formula (a), the recurring units (b1) have the formula (b1) and the recurring units (b2) have the formula (b2):

OG Complex Work Unit Chemistry
 wherein RA is hydrogen or methyl,
X′ is a single bond, phenylene group, naphthylene group, or C1-C12 linking group containing an ester bond, ether bond or lactone ring,
R1 is hydrogen or C1-C4 alkyl,
R2 is a single bond or C1-C6 alkanediyl group,
R3 is hydroxyl,
p is an integer of 1 to 4, q is an integer of 1 to 4, and 2≤p+q≤5,”

OG Complex Work Unit Chemistry
 wherein RA is each independently hydrogen or methyl, Y1 is a single bond, phenylene group, naphthylene group, or C1-C12 linking group containing an ester bond, ether bond or lactone ring, Y2 is a single bond, ester bond or amide bond, Y3 is a single bond, ether bond or ester bond, R11 and R12 each are an acid labile group, R13 is fluorine, trifluoromethyl, cyano or a C1-C6 saturated hydrocarbyl group, R14 is a single bond or a C1-C6 saturated hydrocarbylene group in which some carbon may be replaced by an ether bond or ester bond, a is 1 or 2, and b is an integer of 0 to 4.