Photoresist composition and pattern forming method

Abstract

Disclosed is a photoresist composition comprising: an acid-sensitive polymer comprising repeating units having an acid-labile group; an iodonium salt comprising an anion and a cation, the iodonium salt having the formula (1): wherein Z ‑ It is an organic anion; Ar 1 is a substituted or unsubstituted furan heterocycle containing C 4‑60 heteroaryl; and R 1 is a substituted or unsubstituted hydrocarbon group as provided herein, wherein the cation optionally comprises an acid labile group, wherein Ar 1 and R 1 are optionally linked to each other via a single bond or one or more divalent linking groups to form a ring, and wherein the iodonium salt is optionally linked to each other via Ar 1 or its substituents are covalently bonded to the polymer as pendant groups, the iodonium salt being optionally 1 or its substituents are covalently bonded to the polymer as pendant groups, or the iodonium salt is optionally bonded to the polymer via Z ‑ Covalently bonded to the polymer as a pendant group; and solvent. #imgabs0#

Description

Technical Field

[0001] The present invention relates to photoresist compositions and pattern forming methods using such photoresist compositions. The present invention finds particular applicability in photolithography applications in the semiconductor manufacturing industry. Background Art

[0002] Photoresist materials are light-sensitive compositions typically used to transfer an image onto one or more underlying layers, such as metal, semiconductor, or dielectric layers, disposed on a semiconductor substrate. To increase the integration density of semiconductor devices and allow the formation of structures with dimensions in the nanometer range, photoresists and photolithography processing tools with high-resolution capabilities have been and continue to be developed.

[0003] Positive chemically enhanced photoresists are generally used for high resolution processing. Such resists typically use polymers and photoacid generators (PAGs) with acid labile groups. Patterned exposure to activating radiation by photomask makes the acid generator form acid, and during post-exposure baking, the acid breaks the acid labile groups in the exposed areas of the polymer. This creates a difference in solubility characteristics between the exposure and unexposed areas of the resist in the developer solution. In the positive development (PTD) process, the exposed areas of the photoresist layer become soluble in developer and are removed from the substrate surface, while the unexposed areas that are insoluble in the developer retain to form a positive image after development. Gained relief image allows the selective processing of substrate. See, for example, Uzodinma Okoroanyanwu, Chemistry and Lithography, SPIEPress and John Wiley and Sons, Inc., 2010, and Chris Mack, Fundamental Principles of Optical Lithography, John Wiley and Sons, 2007.

[0004] One approach to achieving nanoscale feature sizes in semiconductor devices is to use short wavelength light, such as 193 nanometers (nm) or shorter, during exposure of chemically amplified photoresists. To further improve lithographic performance, immersion lithography tools (e.g., scanners with KrF (248 nm) or ArF (193 nm) light sources) have been developed to effectively increase the numerical aperture (NA) of the imaging device's lens. This is achieved by using a higher refractive index fluid (typically water) between the final surface of the imaging device and the upper surface of the semiconductor wafer. By using multiple (secondary or higher level) patterning schemes, ArF immersion tools are currently pushing the boundaries of lithography to the 16 nm and 14 nm nodes. However, the use of multiple patterning is typically costly in terms of increased material usage and the number of processing steps required compared to single-step direct imaging patterns. This has provided momentum for the development of next generation technologies such as extreme ultraviolet (EUV) lithography and electron beam lithography. However, as photolithography resolution becomes increasingly higher, line width roughness (LWR), critical dimension uniformity (CDU), and sensitivity of photoresist patterns have become increasingly important in forming high-fidelity patterns.

[0005] EUV and e-beam photoresist compositions and their use have been described in the literature. For example, Japanese Patent Document JP 9183960 A discloses PAG compounds using organoborate anions as counterparts to iodonium cations. However, the use of boron-containing compounds in photolithographic processes is problematic due to the risk of contamination of silicon surfaces, such as silicon surfaces that are undesirably doped with boron, which can adversely alter electronic properties.

[0006] Japanese patent documentation JP 1999153870 A discloses an onium compound with a furan moiety incorporated into a polycationic structure. Using the polycationic structure disadvantageously increases the polarity of the PAG compound and reduces its solubility in organic solvents. The reduced solubility ultimately limits its use in photoresist compositions. In addition, in photoresist compositions, using poorly soluble onium salts typically results in aggregation in the film over an extended period of time and this is converted into unreliable lithographic performance.

[0007] There continues to be a need for photoresist compositions that address one or more of the problems associated with the prior art. In particular, there continues to be a need for photoresist compositions that have good sensitivity at 193 nm and EUV wavelengths, including photoresist compositions that have good solubility and can provide enhanced absorption at EUV wavelengths. Summary of the Invention

[0008] Provided is a photoresist composition comprising: an acid-sensitive polymer comprising a repeating unit having an acid-labile group; and an iodonium salt comprising an anion and a cation, wherein the iodonium salt has formula (1):

[0009]

[0010] where Z - is an organic anion comprising a group selected from the group consisting of sulfonate, methide, sulfonamide, sulfonimide, sulfamate, phenoxide, or carboxylate; Ar 1 is a substituted or unsubstituted furan heterocycle containing C 4-60 heteroaryl; and R 1 It is C 1-20 Alkyl, C 1-20 Heteroalkyl, C 3-20 Cycloalkyl, C 2-20 Heterocycloalkyl, C 2-20 Alkenyl, C 2-20 Heteroalkenyl, C 6-30 Aryl, C 4-30 Heteroaryl, C 7-20 Arylalkyl, or C 4-20 heteroarylalkyl, each of which is substituted or unsubstituted, wherein the cation optionally comprises an acid labile group, wherein Ar 1 and R 1 are optionally linked to each other via a single bond or one or more divalent linking groups to form a ring, and wherein the iodonium salt is optionally linked to each other via Ar 1 or covalently bonded to the polymer via its substituents as pendant groups, the iodonium salt optionally being bonded via R 1 or covalently bonded to the polymer via its substituent as a pendant group, or the iodonium salt is optionally bonded via Z - covalently bonded to the polymer as pendant groups; and solvent.

[0011] Also provided is a pattern forming method comprising (a) applying a layer of the photoresist composition of the present invention on a substrate; (b) pattern-wise exposing the photoresist composition layer to activating radiation; and (c) developing the exposed photoresist composition layer to provide a resist relief image. DETAILED DESCRIPTION

[0012] Reference will now be made in detail to exemplary embodiments, examples of which are presented in this specification. In this regard, the exemplary embodiments may have different forms and should not be construed as limited to the description shown herein. Accordingly, exemplary embodiments are described below solely with reference to the accompanying drawings to illustrate various aspects of this specification. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. When a statement such as "at least one of..." precedes a list of elements, it modifies the entire list of elements and does not modify the individual elements in the list.

[0013] As used herein, the terms "a, an" and "the" do not represent a limit to quantity and are interpreted as including both the singular and the plural unless otherwise indicated herein or clearly contradictory to the context. Unless otherwise expressly indicated, "or" means "and / or". The modifier "about" used in conjunction with quantity includes the value and has the meaning specified by the context (e.g., including the degree of error associated with the measurement of a specific quantity). The full range disclosed herein includes endpoints, and these endpoints are independently combinable with each other. The suffix "(s)" is intended to include both the singular and the plural of the term it modifies, thereby including at least one of the terms. "Optional" or "optionally" means that the event or situation described subsequently may or may not occur, and the description includes examples of the occurrence of the event and examples of its non-occurrence. The terms "first", "second" and similar terms do not represent order, quantity, or importance in this article, but are used to distinguish one element from another. When an element is referred to as being "on" another element, it can be in direct contact with the other element or an intermediate element that may be present therebetween. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. It will be understood that the components, elements, limitations, and / or features of the described aspects may be combined in any suitable manner in the various aspects.

[0014] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as an idealized or overly formal meaning unless expressly defined as such herein.

[0015] As used herein, the term "hydrocarbyl" refers to an organic compound having at least one carbon atom and at least one hydrogen atom, which is optionally substituted where indicated by one or more substituents; "alkyl" refers to a straight or branched chain saturated hydrocarbon having the specified number of carbon atoms and having a valence of 1; "alkylene" refers to an alkyl group having a valence of 2; "hydroxyalkyl" refers to an alkyl group substituted with at least one hydroxyl (-OH) group; "alkoxy" refers to "alkyl-O-"; "carboxylic acid" refers to a group having the formula "-C(=O)-OH"; "cycloalkyl" refers to a monovalent group having one or more saturated rings in which all ring members are carbon; "cycloalkylene" refers to a cycloalkyl group having a valence of 2; "alkenyl" refers to a straight or branched chain monovalent hydrocarbon group having at least one carbon-carbon double bond; "alkenyloxy" refers to "alkenyl-O-"; "alkenylene" refers to a group having a valence of 2. "cycloalkenyl" refers to a non-aromatic cyclic divalent hydrocarbon radical having at least three carbon atoms and at least one carbon-carbon double bond; "alkynyl" refers to a monovalent hydrocarbon radical having at least one carbon-carbon triple bond; the term "aromatic group" refers to a monocyclic or polycyclic ring system that satisfies Huckel's rule and comprises carbon atoms in the ring and optionally may include one or more heteroatoms selected from N, O and S replacing carbon atoms in the ring; "aryl" refers to a monovalent aromatic monocyclic or polycyclic ring system in which each ring member is carbon and may include groups having an aromatic ring fused to at least one cycloalkyl or heterocycloalkyl ring; "arylene" refers to an aryl radical having a valence of 2; "alkylaryl" refers to an aryl radical that has been substituted with an alkyl radical; "arylalkyl" refers to an alkyl radical that has been substituted with an aryl radical; "aryloxy" refers to "aryl-O-"; and "arylthio" refers to "aryl-S-".

[0016] The prefix "hetero" means that the compound or group includes at least one member that is a heteroatom replacing a carbon atom (e.g., 1, 2, 3, or 4, or more heteroatoms), wherein the one or more heteroatoms are each independently N, O, S, Si, or P; a "heteroatom-containing group" refers to a substituent containing at least one heteroatom; a "heteroalkyl" refers to an alkyl group having 1-4 heteroatoms replacing carbon; a "heterocycloalkyl" refers to a cycloalkyl group having 1-4 heteroatoms as ring members replacing carbon; a "heterocycloalkylene" refers to a heterocycloalkyl group having a valence of 2; a "heteroaryl" refers to an aryl group having 1-4 heteroatoms as ring members replacing carbon; and a "heteroarylene" refers to a heteroaryl group having a valence of 2.

[0017] The term "halogen" refers to a monovalent substituent that is fluorine (fluorine / fluoro), chlorine (chlorine / chloro), bromine (bromine / bromo), or iodine (iodine / iodo). The prefix "halo" refers to a group that contains one or more of fluorine, chlorine, bromine, or iodine substituents replacing a hydrogen atom. A combination of halides (e.g., bromine and fluorine) or only fluorine groups can be present.

[0018] "Fluorinated" should be understood to mean having one or more fluorine atoms incorporated into the group. For example, when indicating C 1-18 When a fluoroalkyl group is present, the fluoroalkyl group may include one or more fluorine atoms, such as a single fluorine atom, two fluorine atoms (e.g., as a 1,1-difluoroethyl group), three fluorine atoms (e.g., as a 2,2,2-trifluoroethyl group), or a fluorine atom on each free valence of a carbon (e.g., as a perfluorinated group such as -CF3, -C2F5, -C3F7, or -C4F9). "Substituted fluoroalkyl" is understood to mean a fluoroalkyl group that is further substituted with another substituent.

[0019] "Substituted" means that at least one hydrogen atom on a group is replaced by another group, provided that the normal valence of the designated atom is not exceeded. When the substituent is an oxo group (i.e., =O), then two hydrogens on the carbon atom are replaced. Combinations of substituents or variables are permissible. Exemplary groups that may be present in a "substituted" position include, but are not limited to, nitro (-NO2), cyano (-CN), hydroxyl (-OH), oxo (=O), amino (-NH2), mono- or di- (C 1-6 ) alkylamino, alkanoyl (such as C 2-6 Alkanoyl such as acyl), formyl (-C(=O)H), carboxylic acid or its alkali metal or ammonium salt; ester (including acrylate, methacrylate and lactone) such as C 2-6 Alkyl esters (-C(=O)O-alkyl or -OC(=O)-alkyl) and C 7-13 Aryl ester (-C(=O)O-aryl or -OC(=O)-aryl); amide (-C(=O)NR2, where R is hydrogen or C 1-6 alkyl), carboxamido (-CH2C(=O)NR2, wherein R is hydrogen or C 1-6 alkyl), halogen, mercapto (-SH), C 1-6 Alkylthio (-S-alkyl), thiocyano (-SCN), C 1-6 Alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Halogenated alkyl, C 1-9 Alkoxy, C 1-6 Halogenated alkoxy, C 3-12 Cycloalkyl, C 5-18Cycloalkenyl, C 6-12 Aryl (e.g., phenyl, biphenyl, naphthyl, etc., each ring is substituted or unsubstituted aromatic), C having 1 to 3 separate or fused rings and 6 to 18 ring carbon atoms 7-19 Arylalkyl, arylalkoxy having 1 to 3 separate or fused rings and 6 to 18 ring carbon atoms, C 7-12 Alkyl aryl, C 4-12 Heterocycloalkyl, C 3-12 Heteroaryl, C 1-6 Alkylsulfonyl (-S(=O)2-alkyl), C 6-12 Arylsulfonyl (-S(=O)2-aryl), or tosyl (CH3C6H4SO2-). When a group is substituted, the number of carbon atoms indicated is the total number of carbon atoms in the group, excluding those of any substituents. For example, the group -CH2CH2CN is a C2 alkyl substituted with a cyano group.

[0020] As used herein, " acid-labile group " refers to following group, wherein by the catalytic action of acid (optionally and typically together with heat treatment), key rupture is made, causes the formation of polar group (as carboxylic acid or alcohol group, forms on polymer) and the part of the key that is connected to rupture that is optionally and typically disconnected from polymer.This acid is typically the photogenerated acid under the situation of key cleavage during exposure back baking.Suitable acid-labile group includes, for example: tertiary alkyl ester group, secondary or tertiary aryl ester group, secondary or tertiary ester group with the combination of alkyl and aryl, tertiary alkoxy, acetal group or ketal group.Acid-labile group is also referred to as " acid cleavable group ", " acid cleavable protecting group ", " acid-labile protecting group ", " acid leaving group ", " acid decomposable group " and " acid sensitive group " usually in this area.

[0021] As discussed above, there remains a continuing need for photoresist compositions with improved sensitivity at 193 nm and EUV wavelengths, which, for example, can allow for higher throughput in semiconductor manufacturing. The inventors have discovered that incorporation of oxygen-containing heterocycles (e.g., furans or benzofurans) can be used to improve the sensitivity of photoresists at both 193 nm and EUV exposure wavelengths. These results are unexpected in view of both JP 9183960 A and JP 1999153870 A, as noted above, in which iodonium salts containing furan subunits exhibited limited lithographic performance.

[0022] The present invention relates to a photoresist composition comprising an acid-sensitive polymer comprising repeating units having an acid-labile group, an iodonium salt, a solvent, and may contain additional optional components. The inventors have unexpectedly discovered that the specific photoresist composition of the present invention can achieve significantly improved lithographic performance, such as higher EUV absorbance, faster photospeed, and good solubility in organic solvents.

[0023] Ionium salt comprises iodonium cation and anion part, and for convenience it can be respectively referred to as the cation part and anion part of iodonium salt in this article.Ionium salt is photodecomposable and produces acid when photodecomposition.The intensity of light-generated acid can vary widely depending on the anion part.Depending on the intensity of the acid produced and other components of the photoresist composition, iodonium salt can play a variety of roles in the composition.For example, on the one hand, iodonium salt can serve as the source of acid to deprotect the acid-labile group on the acid-sensitive polymer.On the other hand, iodonium salt can serve as a photodecomposable quencher when used in combination with a photoacid generator (PAG) compound different from the iodonium salt, wherein the corresponding photoacid of the PAG has a pKa lower than the corresponding photoacid of the iodonium salt of the present invention.The photoacid from the iodonium salt can, for example, have a pKa of -20 to 20, -15 to 15, -12 to 12, -15 to -1 or greater than -1 to 6.

[0024] Ionium salts have the formula (1):

[0025]

[0026] In formula (1), Ar 1 is a substituted or unsubstituted furan heterocycle containing C 4-60 Heteroaryl.

[0027] In formula (1), R 1 It is C 1-20 Alkyl, C 1-20 Heteroalkyl, C 3-20 Cycloalkyl, C 2-20 Heterocycloalkyl, C 2-20 Alkenyl, C 2-20 Heteroalkenyl, C 6-30 Aryl, C 4-30 Heteroaryl, C 7-20 Arylalkyl, or C 4-20 heteroarylalkyl, each of which is substituted or unsubstituted.

[0028] In some aspects, Ar 1 Can be selected from the following C 4-60 Heteroaryl:

[0029]

[0030] where R 6a 、R 6b 、R 6c 、R 6d 、R 6e and R 6f are each independently a single bond, hydrogen, substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 1-30 Haloalkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 1-30 Heterocycloalkyl, substituted or unsubstituted C 2-30 Alkenyl, substituted or unsubstituted C 2-30 Alkynyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 7-30 Alkylaryl, substituted or unsubstituted C 3-30 Heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, halogen, -OR 61 、-SR 62 , or -NR 63 R 64 , where R 61 to R 64 are each independently hydrogen, or substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 2-30 Heterocycloalkyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 3-30 Heteroaryl, or substituted or unsubstituted C 4-30 Heteroarylalkyl, provided that R 6a 、R 6b 、R 6c 、R 6d 、R 6e or R 6f One of the is a single bond to the iodonium cation. In the above formula, m is an integer from 0 to 6, n is an integer from 0 to 6, and x is an integer from 1 to 6.

[0031] In some respects, R 1 It may contain one or more of the following formulae as all or part of its structure:

[0032]

[0033] wherein n is an integer from 0 to 6, and "*" indicates the point of attachment to the iodine atom.

[0034] In some respects, R 1 Can be C 4-60 Heteroaryl, wherein the C 4-60 Heteroaryl is as above for Ar 1 As defined. 1 It is C 4-60 When heteroaryl, Ar 1 and R 1 They may be the same as or different from each other.

[0035] Exemplary cationic moieties having formula (1) include the following:

[0036]

[0037]

[0038]

[0039] In some aspects, Ar 1 and R 1 They may optionally be linked to each other via a single bond or one or more divalent linking groups L to form a ring having formula (1a):

[0040]

[0041] Suitable one or more divalent linking groups L include, for example, one or more of the following: -O-, -S-, -Te-, -Se-, -C(O)-, C(O)-O-, -N(R a )-、-C(O)-N(R 2a )、-S(O)-、-S(O)2-、-N(R 2a )-S(O)2-, -C(S)-, -C(Te)-, -C(Se)-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted C 7-30 Arylenealkyl, substituted or unsubstituted C 1-30 Heteroarylene, substituted or unsubstituted C 3-30 Heteroarylene alkyl, or with Ar 1 or R 1 A single bond forming part of a ring; wherein R a and R 2a It is hydrogen, C 1-20 Alkyl, C1-20 Heteroalkyl, C 6-30 Aryl or C 4-30 Heteroaryl, wherein each of the groups except hydrogen may be substituted or unsubstituted. Preferably, Ar 1 and R 1 It can be optionally connected via -O-, -S-, -Te-, -Se-, -C(O)-, -C(S)-, -C(Te)-, -C(Se)-, or substituted or unsubstituted C 1-5 One or more of the alkylene groups are linked to each other.

[0042] Among them, Ar 1 and R 1 Non-limiting examples of rings linked to each other via a single bond or one or more divalent linking groups to form a ring having formula (1a) include:

[0043]

[0044] The iodonium salt of formula (1) can be included in the photoresist composition as a non-polymeric compound and / or in polymeric form, for example, in a polymeric repeat unit of an acid-sensitive polymer as described herein or as part of a different polymer. In some aspects, the iodonium salt of formula (1) can be optionally reacted with Ar 1 or R 1 , or through Ar 1 or R 1 The respective substituents are covalently bonded to the polymer as pendant groups, or, for example, iodonium salts of formula (1) may optionally be attached via Z - covalently bonded to the polymer as a pendant group. That is, the iodonium salt having formula (1) may optionally be bonded to the polymer via Ar 1 or covalently bonded to the polymer via its substituents as pendant groups, the iodonium salt of formula (1) may optionally be bonded via R 1 or covalently bonded to the polymer as a side group via its substituent, or the anionic portion of the iodonium salt of formula (1) can optionally be bonded via Z - Covalently bonded to the polymer as a pendant group. For example, the pendant group can be attached to the main chain or backbone of the polymer.

[0045] For example, the polymer optionally may comprise repeat units containing an iodonium salt, such as repeat units derived from one or more monomers having formula (2a), (2b), or (3):

[0046]

[0047] Among them, Ar 1 and R 1 is as defined herein.

[0048] In formulas (2a), (2b) and (3), R a 、R b and R c are each independently hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R a 、R b and R c are each independently hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl).

[0049] In formulas (2a), (2b) and (3), Q 1 , Q 2 and Q 3 are each independently a single bond or a divalent linking group selected from one or more of the following: a heteroatom, a substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted C 4-30 Preferably, Q 1 , Q 2 and Q 3 Each independently may contain 1 to 10 carbon atoms and at least one heteroatom, more preferably -C(O)-O-.

[0050] In formulas (2a), (2b) and (3), A 1 、A 2 and A 3 Each independently is one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, or substituted or unsubstituted C 4-30 Preferably, A 1 、A 2 and A 3 Each independently is an optionally substituted divalent C 1-30 Perfluoroalkylene.

[0051] In formulas (1), (2a), (2b) and (3), Z - is an organic anion comprising a group selected from the group consisting of sulfonate, methide, sulfonamide, sulfonylimide, sulfamate, phenoxide, or carboxylate.

[0052] Exemplary organic anions having a sulfonate group include the following:

[0053]

[0054]

[0055] Exemplary non-sulfonated organic anions include the following:

[0056]

[0057] In some aspects, the iodonium salt can be prepared by Z - Covalently bonded to the polymer as a pendant group. Such iodonium salts may comprise repeating units derived from exemplary monomers having formula (3);

[0058]

[0059]

[0060] Among them, Ar 1 and R 1 is as defined herein.

[0061] If used in a polymer, such iodonium salt-containing repeating units are typically present in an amount of 1 to 20 mol%, more typically 1 to 10 mol%, and still more typically 2 to 8 mol%, based on the total repeating units in the polymer.

[0062] Polymkeric substance can optionally comprise one or more other repeating units that are different from the repeating unit that comprises iodonium salt.Other repeating unit can comprise one or more other units for characteristic (such as etch rate and solubility) purpose for regulating photoresist composition.Exemplary other unit can comprise one or more in (methyl) acrylate, vinyl ether, vinyl ketone and vinyl ester.One or more other repeating units in polymkeric substance (if existing) typically use with the amount of up to 99mol% and typically 3 to 80mol% based on the total repeating unit of polymkeric substance.

[0063] The polymer typically has an M of 1,000 to 50,000 Da, specifically 2,000 to 30,000 Da, more specifically 3,000 to 20,000 Da, still more specifically 3,000 to 10,000 Da. w The PDI of the polymer (which is M w With M n The ratio of ) is typically 1.1 to 3, specifically 1.1 to 2. The molecular weight is determined by GPC using polystyrene standards.

[0064] In some aspects, the cationic portion of the iodonium salt having formula (1) may include an acid-labile group that can be cleaved by photogenerated acid under post-exposure bake conditions. 1 and R 1 Each of the groups may optionally contain an acid-labile group selected from, for example, a tertiary alkyl ester group, a tertiary aryl ester group, a tertiary ester group having a combination of an alkyl group and an aryl group, a tertiary alkoxy group, an acetal group, or a ketal group. 1 or R 1 The divalent linking group of the group may include -O-, -S-, -Te-, -Se-, -C(O)-, -C(O)O-, -C(S)-, -C(S)-O-, C(O)-S, -C(Te)-, -S(O)-, -S(O)2-, -N(R)-, -C(Se)-, substituted or unsubstituted C 1-5 Alkylene, and combinations thereof, wherein R is hydrogen, C 1-20 Alkyl, C 1-20 Heteroalkyl, C 6-30 Aryl or C 4-30 Heteroaryl, wherein each of the groups except hydrogen may be substituted or unsubstituted. Alternatively, the acid labile group may be linked to the corresponding Ar via a single bond (i.e., the divalent linking group may be omitted in some embodiments). 1 or R 1 group.

[0065] The acid-sensitive polymers of the present invention comprise repeating units having acid-labile groups. For example, the repeating units having acid-labile groups can be derived from one or more monomers having formula (4a), (4b), (4c), (4d), or (4e):

[0066]

[0067] In formulas (4a), (4b) and (4c), R d is hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R d is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl).

[0068] In formula (4a), L 1 is a divalent linking group comprising at least one carbon atom, at least one heteroatom, or a combination thereof. For example, L 2 May contain 1 to 10 carbon atoms and at least one heteroatom. In a typical embodiment, L 1It can be -OCH2-, -OCH2CH2O- or -N(R 21 )-, where R 21 is hydrogen or C 1-6 alkyl.

[0069] In formulas (4a) and (4b), R 1 to R 6 are each independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 1-20 Heterocycloalkyl, linear or branched C 2-20 Alkenyl, monocyclic or polycyclic C 3-20 Cycloalkenyl, monocyclic or polycyclic C 3-20 Heterocycloalkenyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 2-20 Heteroaryl, wherein each except hydrogen is substituted or unsubstituted; provided that R 1 to R 3 Only one of them can be hydrogen, and R 4 to R 6 Only one of them can be hydrogen, and only if R 1 to R 3 When one of the 1 to R 3 The remaining one or two are substituted or unsubstituted monocyclic or polycyclic C 6-20 Aryl or substituted or unsubstituted monocyclic or polycyclic C 4-20 heteroaryl, and when R 4 to R 6 When one of the 4 to R 6 The remaining one or two are substituted or unsubstituted monocyclic or polycyclic C 6-20 Aryl or substituted or unsubstituted monocyclic or polycyclic C 4-20 Preferably, R 1 to R 6 Each independently is a linear or branched C 1-6 Alkyl, or monocyclic or polycyclic C 3-10 cycloalkyl, each of which is substituted or unsubstituted.

[0070] In formula (4a), R 1 to R 3 Any two of together optionally form a ring, and R 1 to R 3 Each of which may optionally include as part of its structure a radical selected from -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R42 )-S(O)2-, wherein R 42 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 1-20 Heterocycloalkyl. In formula (4b), R 4 to R 6 Any two of together optionally form a ring, and R 4 to R 6 Each of which may optionally include as part of its structure a radical selected from -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 43 )-S(O)2-, wherein R 43 is hydrogen, straight-chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 1-20 Heterocycloalkyl. For example, R 1 to R 6 Any one or more of may independently be of the formula -CH2C(=O)CH (3-n) Y n wherein each Y is independently substituted or unsubstituted C 1-30 heterocycloalkyl and n is 1 or 2. For example, each Y can independently be a substituted or unsubstituted radical comprising a radical having the formula -O(C a1 )(C a2 )O- 1-30 Heterocycloalkyl, wherein C a1 and C a2 are each independently hydrogen or substituted or unsubstituted alkyl, and wherein C a1 and C a2 together optionally forming a ring.

[0071] In formulas (4c) and (4e), R 7 to R 8 can be independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 1-20 Heterocycloalkyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 2-20 heteroaryl, each of which is substituted or unsubstituted; and R 9 Is a straight chain or branched chain C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 1-30Heterocycloalkyl, each of which is substituted or unsubstituted. Optionally, R 7 or R 8 One of the 9 Together they form a heterocyclic ring. Preferably, R 7 and R 8 can be independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 1-20 Heterocycloalkyl.

[0072] In formula (4d), R 10 to R 12 can be independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 1-20 Heterocycloalkyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 2-20 Heteroaryl, wherein each of the groups except hydrogen is substituted or unsubstituted, R 10 to R 12 Any two of together optionally form a ring, and R 10 to R 12 Each of which optionally may contain as part of its structure a radical selected from -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 44 )-S(O)2-, wherein R 44 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 1-20 heterocycloalkyl; provided that when the acid-labile group is not an acetal group, R 10 to R 12 Only one of them can be hydrogen, provided that when R 10 to R 12 When one of the 10 to R 12 The remaining one or two are substituted or unsubstituted monocyclic or polycyclic C 6-20 Aryl or substituted or unsubstituted monocyclic or polycyclic C 4-20 Heteroaryl.

[0073] In formulas (4d) and (4e), X a is a polymerizable group selected from vinyl and norbornyl; and L 2 is a single bond or a divalent linking group, provided that when X a When it is vinyl, L 2is not a single bond. Preferably, L 2 Is a monocyclic or polycyclic C 6-30 Arylene, or monocyclic or polycyclic C 6-30 Cycloalkylene, each of which may be substituted or unsubstituted. In formulas (4d) and (4e), n is 0 or 1. It should be understood that when n is 0, L 2 The group is directly attached to the oxygen atom.

[0074] Non-limiting examples of monomer (4a) include:

[0075]

[0076] Non-limiting examples of monomers having formula (4b) include:

[0077]

[0078]

[0079] where R d is as defined above; and R ’ and R" are each independently a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 1-20 Heterocycloalkyl, linear or branched C 2-20 Alkenyl, monocyclic or polycyclic C 3-20 Cycloalkenyl, monocyclic or polycyclic C 3-20 Heterocycloalkenyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 4-20 heteroaryl, each of which is substituted or unsubstituted.

[0080] Non-limiting examples of monomers having formula (4c) include:

[0081]

[0082] where R d is as defined above.

[0083] Non-limiting examples of monomer (4d) include:

[0084]

[0085] Non-limiting examples of monomer (4e) include:

[0086]

[0087] In yet another example, the repeating units of the polymer having acid labile groups can be derived from one or more monomers having cyclic acetal or cyclic ketal groups, such as monomers having the formula:

[0088]

[0089] where R d is as defined above.

[0090] In yet another example, the repeating units of the polymer having an acid labile group can be derived from one or more monomers having a tertiary alkoxy group, such as a monomer having the formula:

[0091]

[0092] The repeating unit having an acid labile group is typically present in the acid sensitive polymer in an amount of 10 to 80 mol%, more typically 25 to 75 mol%, still more typically 30 to 70 mol%, based on the total repeating units in the acid sensitive polymer.

[0093] In some aspects, the acid-sensitive polymer may comprise repeating units having aromatic groups, wherein the aromatic groups may be substituted or unsubstituted. The aromatic groups are monocyclic or polycyclic C-terminal rings optionally comprising one or more aromatic ring heteroatoms selected from N, O, S, or a combination thereof. 5-60 Aromatic group. When C 5-60 When the aromatic group is polycyclic, the rings or ring groups may be fused (e.g., naphthyl, etc.), directly linked (e.g., biaryl, biphenyl, etc.), bridged through heteroatoms (e.g., triphenylamino or diphenylene ether), and / or may include a combination of fused and directly linked rings (e.g., binaphthyl, etc.).

[0094] Monocyclic or polycyclic C 5-60 Aromatic groups may be substituted or unsubstituted. Exemplary substituents include, but are not limited to, substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 1-30 Haloalkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 1-30 Heterocycloalkyl, substituted or unsubstituted C 2-30 Alkenyl, substituted or unsubstituted C 2-30 Alkynyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 7-30 Alkylaryl, substituted or unsubstituted C 3-30 Heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, halogen, -OR51 、-SR 52 , or -NR 53 R 54 , where R 51 to R 54 are each independently hydrogen, or substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 2-30 Heterocycloalkyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 3-30 Heteroaryl, or substituted or unsubstituted C 4-30 Preferably, the aromatic group is a substituted C 6-30 Aryl or substituted C 7-30 Heteroaryl, in which the aromatic group is replaced by a heteroatom-containing substituent such as -OR 51 、-SR 52 , or -NR 53 R 54 Substituted, where R 51 to R 54 are each independently hydrogen, or substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 3-20 Cycloalkyl, substituted or unsubstituted C 2-20 Heterocycloalkyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 3-30 Heteroaryl, or substituted or unsubstituted C 4-30 Heteroarylalkyl.

[0095] The repeating units having an aromatic group are typically present in the acid-sensitive polymer in an amount of 5 to 80 mol%, more typically 10 to 50 mol%, still more typically 10 to 40 mol%, based on the total repeating units in the acid-sensitive polymer.

[0096] The acid-sensitive polymer may comprise lactone repeat units derived from a monomer having formula (5):

[0097]

[0098] In formula (5), R f is hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R f is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl).3 It may be a single bond or a divalent linking group comprising one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 1-30 Heteroalkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted C 7-30 Arylenealkyl, or substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted C 3-30 Heteroarylenealkyl, wherein L 3 Optionally, it may further comprise a group selected from, for example, -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 44 )-S(O)2-, wherein R 44 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl. 14 It can be a monocyclic, polycyclic, or fused polycyclic C 4-20 Contains lactone group.

[0099] Non-limiting examples of monomers having formula (5) include:

[0100]

[0101]

[0102] where R f As disclosed herein.

[0103] When present, the acid sensitive polymer typically comprises lactone repeat units in an amount of 5 to 60 mol%, typically 20 to 55 mol%, more typically 25 to 50 mol%, based on the total repeat units in the acid sensitive polymer.

[0104] The acid-sensitive polymer may comprise an alkali-soluble repeating unit having a pKa less than or equal to 12. For example, the alkali-soluble repeating unit may be derived from a monomer having formula (6):

[0105]

[0106] In formula (6), R g It can be hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10Preferably, R g is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl). Q 4 Can be one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted divalent C 7-30 Arylalkyl, substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted divalent C 3-30 Heteroarylalkyl or -C(O)-O-. W is an alkali-soluble group and can be selected from, for example, hydroxyl (-OH); -C(O)-OH; fluorinated alcohols such as -C(CF3)2OH; amides; imides; or -NH-S(O)2-Y 1 , where Y 1 Is F or C 1-4 In formula (6), a is an integer from 1 to 3.

[0107] Non-limiting examples of monomers having formula (6) include:

[0108]

[0109] where R g and Y 1 is as described above.

[0110] Other base-soluble groups may be N-hydroxyarylmaleimides having the following structure:

[0111]

[0112] Among them, Ar 2 is a hydroxy-substituted C 6-60 Aryl, hydroxy substituted C 4-60 Heteroaryl, or a combination thereof, optionally further substituted with one or more of: substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 1-30 Heteroalkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 1-30 Heterocycloalkyl, substituted or unsubstituted C 2-30 Alkenyl, substituted or unsubstituted C 2-30 Alkynyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 7-30Alkylaryl, substituted or unsubstituted C 2-30 Heteroaryl, substituted or unsubstituted C 3-30 Heteroarylalkyl, C 3-30 Alkylheteroaryl, -OR 21 、-NH2、-NHR 22 or -NR 23 R 24 , where R 21 to R 24 are each independently substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 1-30 Heterocycloalkyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 7-30 Alkylaryl, substituted or unsubstituted C 4-30 Heteroaryl, substituted or unsubstituted C 5-30 Heteroarylalkyl, or substituted or unsubstituted C 5-30 Alkyl heteroaryl. 2 Containing a single hydroxyl group or multiple hydroxyl groups (e.g., Ar 2 It can be a hydroxy-substituted C 6-60 Aryl, hydroxy substituted C 4-60 heteroaryl, or combinations thereof, each of which is independently optionally further substituted with hydroxyl). Non-limiting examples of monomers include the following:

[0113] When present, the base-soluble repeat units may be present in the acid-sensitive polymer in an amount of 2 to 75 mol%, typically 5 to 25 mol%, more typically 5 to 15 mol%, based on the total repeat units in the acid-sensitive polymer.

[0114] Non-limiting examples of acid-sensitive polymers include the following:

[0115]

[0116]

[0117]

[0118]

[0119] wherein a, b, c, and d represent the mole fractions of the corresponding repeating units, and n is an integer from 10 to 1,000.

[0120] The acid-sensitive polymer can randomly comprise one or more other repeating units.Other repeating units can comprise one or more other units for example for characteristic (such as etch rate and solubility) purpose of regulating photoresist composition.Exemplary other unit can comprise one or more in (methyl) acrylate, vinyl ether, vinyl ketone and vinyl ester.One or more other repeating units in the acid-sensitive polymer (if present) can be up to 70mol%, typically 3 to 50mol% amount use with the total repeating units based on the acid-sensitive polymer.

[0121] The acid-sensitive polymer typically has a weight average molecular weight (MW) of 1,000 to 50,000 Daltons (Da), specifically 2,000 to 30,000 Daltons (Da), more specifically 3,000 to 20,000 Daltons (Da), and even more specifically 3,000 to 10,000 Daltons (Da). w The polydispersity index (PDI) of the acid-sensitive polymer (which is the M w and number average molecular weight (M n ) is typically 1.1 to 3, specifically 1.1 to 2. Molecular weight values are determined by gel permeation chromatography (GPC) using polystyrene standards.

[0122] The photoresist composition may further comprise a PAG compound in addition to the iodonium salt compound. The additional PAG compound typically has a pKa of -15 to 1. The PAG may be in a non-polymeric form or in a polymeric form, for example, present in a polymerized repeat unit of an acid-sensitive polymer as described above, or as part of a different polymer. Suitable non-polymeric photoacid generator compounds may have the formula G + A - , where G + is an organic cation selected from iodonium cations substituted with two alkyl groups, two aryl groups, or a combination of alkyl and aryl groups; and sulfonium cations substituted with three alkyl groups, three aryl groups, or a combination of alkyl and aryl groups; and A - It is a non-polymerizable organic anion.

[0123] Particularly suitable non-polymeric organic anions include those whose conjugate acid has a pKa of -15 to 1. Particularly preferred anions are fluorinated alkylsulfonate and fluorinated sulfonimide anions.

[0124] Suitable non-polymeric PAG compounds are known in the art of chemically amplified photoresists and include, for example, onium salts such as triphenylsulfonium trifluoromethanesulfonate, (p-tert-butoxyphenyl)diphenylsulfonium trifluoromethanesulfonate, tris(p-tert-butoxyphenyl)sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate; di-tert-butylphenyliodonium perfluorobutanesulfonate and di-tert-butylphenyliodonium camphorsulfonate. Also known are nonionic sulfonates and sulfonyl compounds that act as photoacid generators, such as nitrobenzyl derivatives, for example, 2-nitrobenzyl-p-toluenesulfonate, 2,6-dinitrobenzyl-p-toluenesulfonate, and 2,4-dinitrobenzyl-p-toluenesulfonate; sulfonic acid esters, for example, 1,2,3-tris(methylsulfonyloxy)benzene, 1,2,3-tris(trifluoromethylsulfonyloxy)benzene, and 1,2,3-tris(p-toluenesulfonyloxy)benzene; diazomethane derivatives, for example, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane; ethylenediamine derivatives, for example, bis(benzenesulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane; and ethylenediamine derivatives. Oxime derivatives, such as bis-O-(p-toluenesulfonyl)-α-dimethylglyoxime and bis-O-(n-butanesulfonyl)-α-dimethylglyoxime; sulfonate derivatives of N-hydroxyimide compounds, such as N-hydroxysuccinimide methanesulfonate and N-hydroxysuccinimide trifluoromethanesulfonate; and halogen-containing triazine compounds, such as 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine and 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine. Suitable non-polymeric photoacid generators are further described in U.S. Patent No. 8,431,325 to Hashimoto et al., at column 37, lines 11-47 and columns 41-91. Other suitable sulfonate PAGs include sulfonated esters and sulfonyloxyketones, nitrobenzyl esters, s-triazine derivatives, benzoin tosylate, α-(p-toluenesulfonyloxy)-acetic acid tert-butylphenyl ester, and α-(p-toluenesulfonyloxy)-acetic acid tert-butyl ester; as described in U.S. Pat. Nos. 4,189,323 and 8,431,325.

[0125] Typically, when the photoresist composition includes a non-polymeric photoacid generator, the photoacid generator is present in the photoresist composition in an amount of 2 to 65 wt %, more typically 5 to 55 wt %, based on the total solids of the photoresist composition.

[0126] In other aspects, the acid-sensitive polymer or a different polymer optionally can comprise repeat units comprising PAG repeat units derived from formula (7):

[0127]

[0128] In formula (7), R h is hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10Alkyl, substituted or unsubstituted C 1-10 Preferably, R h is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl). Q 5 is a single bond or a divalent linking group selected from one or more of the following: a heteroatom, a substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted divalent C 7-30 Arylalkyl, substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted divalent C 3-30 Heteroarylalkyl, or a combination thereof. Preferably, Q 5 It may contain 1 to 10 carbon atoms and at least one heteroatom, more preferably -C(O)-O-.

[0129] In formula (7), A 4 is one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted divalent C 7-30 Arylalkyl, substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted divalent C 3-30 Preferably, A 4 is an optionally substituted divalent C 1-30 Perfluoroalkyl.

[0130] In formula (7), Z - is an anionic moiety whose conjugate acid typically has a pKa of -15 to 1. Particularly preferred anions of this type are fluorinated alkylsulfonate and fluorinated sulfonimide anions.

[0131] In formula (7), G + is an organic cation selected from iodonium cations substituted with two alkyl groups, two aryl groups, or a combination of alkyl and aryl groups; and sulfonium cations substituted with three alkyl groups, three aryl groups, or a combination of alkyl and aryl groups. In some embodiments, G + is an iodonium cation substituted with two alkyl groups, two aryl groups, or a combination of alkyl and aryl groups; or a sulfonium cation substituted with three alkyl groups, three aryl groups, or a combination of alkyl and aryl groups. Preferably, the photoacid generator comprises a sulfonium cation.

[0132] Exemplary monomers having formula (7) include the following:

[0133]

[0134] Among them G + It is an organic cation.

[0135] In some embodiments, G + is a sulfonium cation having the following formula (8A) or an iodonium cation having the following formula (8B):

[0136]

[0137] Among them, each R aa Independently C 1-20 Alkyl, C 1-20 Fluoroalkyl, C 3-20 Cycloalkyl, C 3-20 Fluorocycloalkyl, C 2-20 Alkenyl, C 2-20 Fluoroalkenyl, C 6-30 Aryl, C 6-30 Fluoroaryl, C 6-30 Iodoaryl, C 1-30 Heteroaryl, C 7-20 Arylalkyl, C 7-20 Fluoroarylalkyl, C 2-20 Heteroarylalkyl, or C 2-20 Fluoroheteroarylalkyl, each of which is substituted or unsubstituted, wherein each R aa is independent or connected to another group R via a single bond or a divalent linking group aa Form a ring. Each R aa Optionally, it may contain one or more groups selected from the group consisting of: -O-, -C(O)-, -C(O)-O-, -C 1-12 Alkylidene-, -O-(C 1-12 alkylene)-、-C(O)-O-(C 1-12 alkylene)- and -C(O)-O-(C 1-12 Alkylene)-O-. Each R aa Independently, it may optionally contain an acid labile group selected from, for example, a tertiary alkyl ester group, a secondary or tertiary aryl ester group, a secondary or tertiary ester group having a combination of alkyl and aryl groups, a tertiary alkoxy group, an acetal group, or a ketal group. aa The divalent linking group of the group includes, for example, -O-, -S-, -Te-, -Se-, -C(O)-, -C(S)-, -C(Te)- or -C(Se)-, substituted or unsubstituted C 1-5 Alkylene, and combinations thereof.

[0138] Exemplary sulfonium cations having formula (8A) include the following:

[0139]

[0140]

[0141] Exemplary iodonium cations having formula (8B) include the following:

[0142]

[0143] The polymer and / or acid-sensitive polymer may optionally comprise repeating units comprising a PAG derived from a monomer having formula (5), as disclosed above. The polymer and / or acid-sensitive polymer may comprise repeating units comprising a photoacid generator in an amount of 1 to 15 mol%, typically 1 to 8 mol%, more typically 2 to 6 mol%, based on the total repeating units in the polymer and / or acid-sensitive polymer.

[0144] In the photoresist composition of the present invention, the acid-sensitive polymer is typically present in the photoresist composition in an amount of 0.5 to 99.9 wt %, typically 1 to 15 wt %, more typically 1 to 10 wt % based on the total solids of the photoresist composition. It will be understood that the total solids include polymer, PAG, and other non-solvent components.

[0145] In some aspects, the photoresist composition can further include a material ("base unstable material") comprising one or more alkali unstable groups. As mentioned herein, the alkali unstable group is a functional group that can undergo a cleavage reaction to provide a polar group (such as a hydroxyl, carboxylic acid, sulfonic acid, etc.) in the presence of an aqueous alkali developer after the exposure step and the post-exposure baking step. The alkali unstable group will not undergo a significant reaction (such as a bond cleavage reaction) before the developing step of the photoresist composition comprising the alkali unstable group. Therefore, such as, the alkali unstable group will be substantially inert during the soft baking step before exposure, the exposure step, and the post-exposure baking step. "Substantially inert" means that ≤5%, preferably ≤1% of the alkali unstable group (or part) will decompose, crack, or react during the soft baking step before exposure, the exposure step, and the post-exposure baking step. The alkali unstable group is reactive under the photoresist developing conditions of a typical use, for example, an aqueous alkali photoresist developer (such as 0.26 standard (N) tetramethylammonium hydroxide (TMAH) aqueous solution). In some embodiments, the TMAH developer of the present invention is used to develop the resist pattern by using a single immersion developer or a dynamic development process. For example, the TMAH aqueous solution of 0.26N can be used to develop the resist pattern using a single immersion developer or a dynamic development process, and for example, the TMAH developer of 0.26N is assigned to the photoresist layer of imaging and continues a suitable period of time (for example 10 to 120 seconds (s)). Exemplary alkali unstable groups are ester groups, typically fluorinated ester groups. Preferably, the unstable material of alkali is substantially not miscible with the first and second polymers and other solid components of photoresist composition and has a surface energy lower than them. Thereby when being coated on substrate, the unstable material of alkali can be separated from other solid components of photoresist composition and arrives at the top surface of the photoresist layer formed.

[0146] In some aspects, the base-labile material is a polymeric material (also referred to herein as a base-labile polymer) that can include one or more repeating units comprising one or more base-labile groups. For example, the base-labile polymer can include repeating units containing 2 or more identical or different base-labile groups. Preferred base-labile polymers include at least one repeating unit comprising 2 or more base-labile groups, for example, repeating units comprising 2 or 3 base-labile groups.

[0147] The base labile polymer may be a polymer comprising repeating units derived from a monomer having formula (E1):

[0148]

[0149] where X b is a polymerizable group selected from vinyl and acrylic acid, L 5 is a divalent linking group comprising one or more of the following: substituted or unsubstituted linear or branched C 1-20Alkylene, substituted or unsubstituted C 3-20 Cycloalkylene, -C(O)- or -C(O)O-; and R k is substituted or unsubstituted C 1-20 Fluoroalkyl group, provided that the carbon atom bonded to the carbonyl group (C═O) in formula (E1) is substituted with at least one fluorine atom.

[0150] Exemplary monomers having formula (E1) include the following:

[0151]

[0152] The base-labile polymer may comprise repeating units comprising two or more base-labile groups. For example, the base-labile polymer may comprise repeating units derived from a monomer having formula (E2):

[0153]

[0154] where X b and R k is as defined in formula (E1); L 6 is a polyvalent linking group comprising one or more of the following: substituted or unsubstituted linear or branched C 1-20 Alkylene, substituted or unsubstituted C 3-20 cycloalkylene, -C(O)- or -C(O)O-; and n is an integer of 2 or greater, for example, 2 or 3.

[0155] Exemplary monomers having formula (E2) include the following:

[0156]

[0157] The base-labile polymer may comprise repeating units comprising one or more base-labile groups. For example, the base-labile polymer may comprise repeating units derived from a monomer having formula (E3):

[0158]

[0159] where X b is as defined in formula (E1); L 7 is a divalent linking group comprising one or more of the following: substituted or unsubstituted linear or branched C 1-20 Alkylene, substituted or unsubstituted C 3-20 Cycloalkylene, -C(O)- or -C(O)O-; L f is substituted or unsubstituted C 1-20 A fluoroalkylene group, wherein the carbon atom bonded to the carbonyl group (C=O) in formula (E3) is substituted with at least one fluorine atom; and R mis a substituted or unsubstituted straight or branched chain C 1-20 Alkyl, substituted or unsubstituted C 3-20 Cycloalkyl.

[0160] Exemplary monomers having formula (E3) include the following:

[0161]

[0162] In another preferred aspect of the present invention, the unstable polymer of alkali can comprise one or more unstable groups of alkali and one or more unstable groups of acid, such as one or more unstable ester moieties of acid (such as tert-butyl ester) or unstable acetal groups of acid.For example, the unstable polymer of alkali can comprise the repeating unit that comprises unstable groups of alkali and unstable groups of acid, that is, wherein unstable groups of alkali and unstable groups of acid are both present on same repeating unit.In another example, the unstable polymer of alkali can comprise the first repeating unit that contains unstable groups of alkali and the second repeating unit that contains unstable groups of acid.Preferred photoresist of the present invention can show the defect relevant with the resist relief image formed by photoresist composition of reduction.

[0163] Base-labile polymers can be prepared using any suitable method in the art, including those described herein for the first and second polymers. For example, base-labile polymers can be obtained by polymerization of the corresponding monomers under any suitable conditions, such as by heating at an effective temperature, irradiation with actinic radiation at an effective wavelength, or a combination thereof. Additionally or alternatively, one or more base-labile groups can be grafted onto the polymer backbone using a suitable method.

[0164] In some aspects, the base labile material is a single molecule comprising one or more base labile ester groups, preferably one or more fluorinated ester groups. The base labile material that is a single molecule may have an M of 50 to 1,500 Da. W Exemplary base labile materials include the following:

[0165]

[0166] The photoresist composition can further comprise except above-mentioned polymer and acid-sensitive polymer and one or more polymers different therefrom.For example, the photoresist composition can comprise as above-mentioned but composition different other polymer, or be similar to above-mentioned those but do not comprise the polymer of essential repeating unit.In addition or alternatively, one or more other polymers can include those well-known in the photoresist field, for example, be selected from following those: polyacrylate, polyvinyl ether, polyester, polynorbornene, polyacetal, polyethylene glycol, polyamide, polyacrylamide, polyphenol, novolac, styrene polymer, polyvinyl alcohol or its combination.

[0167] The photoresist composition further comprises a solvent for dissolving the components of the composition and promoting its coating on the substrate. Preferably, the solvent is an organic solvent conventionally used in the manufacture of electronic devices. Suitable solvents include, for example: aliphatic hydrocarbons such as hexane or heptane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane and 1-chlorohexane; alcohols such as methanol, ethanol, 1-propanol, isopropanol, tert-butanol, 2-methyl-2-butanol, 4-methyl-2-pentanol and diacetone alcohol (4-hydroxy-4-methyl-2-pentanone); propylene glycol monomethyl ether (PGME); ethers such as diethyl ether, tetrahydrofuran, 1,4-dioxane and anisole; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, 2-heptanone and cyclohexane. Ketone (CHO); esters such as ethyl acetate, n-butyl acetate, propylene glycol monomethyl ether acetate (PGMEA), ethyl lactate (EL), methyl hydroxyisobutyrate (HBM) and ethyl pyruvate; lactones such as γ-butyrolactone (GBL) and ε-caprolactone; lactams such as N-methylpyrrolidone; nitriles such as acetonitrile and propionitrile; cyclic or non-cyclic carbonates such as propylene carbonate, dimethyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate and propylene carbonate; polar aprotic solvents such as dimethyl sulfoxide and dimethylformamide; water; and combinations thereof. Among these, preferred solvents are PGME, PGMEA, EL, GBL, HBM, CHO, and combinations thereof. The total solvent content in the photoresist composition (i.e., the cumulative solvent content of all solvents) is typically 40 to 99 wt%, for example 70 to 99 wt%, or 85 to 99 wt%, based on the total solids of the photoresist composition. The desired solvent content will depend, for example, on the desired thickness of the applied photoresist layer and the coating conditions.

[0168] The photoresist composition may further comprise one or more additional optional additives. For example, the optional additives may include actinic and contrast dyes, anti-striation agents, plasticizers, speed enhancers, sensitizers, photodegradable quenchers (PDQs) (also known as photodegradable bases), alkaline quenchers, surfactants, etc., or combinations thereof. If present, the optional additives are typically present in the photoresist composition in an amount of 0.01 to 10 wt % based on the total solids of the photoresist composition.

[0169] The photodecomposable quencher generates a weak acid upon irradiation. The acid generated by the photodecomposable quencher is not strong enough to react rapidly with the acid-labile groups present in the resist matrix. Exemplary photodecomposable quenchers include, for example, photodecomposable cations, and preferably can also be used to prepare strong acid generator compounds but are not suitable for use with weak acids (pKa>1) such as, for example, C 1-20 Carboxylic acid or C 1-20 Examples of the photodegradable quencher include those that are paired with an anion of a sulfonic acid (e.g., a succinic acid). Exemplary carboxylic acids include formic acid, acetic acid, propionic acid, tartaric acid, succinic acid, cyclohexanecarboxylic acid, benzoic acid, salicylic acid, and the like. Exemplary carboxylic acids include p-toluenesulfonic acid, camphorsulfonic acid, and the like. In a preferred embodiment, the photodegradable quencher is a photodegradable organic zwitterionic compound, such as diphenyliodonium-2-carboxylate.

[0170] Exemplary basic quenchers include, for example: linear aliphatic amines such as tributylamine, trioctylamine, triisopropanolamine, tetrakis(2-hydroxypropyl)ethylenediamine; n-tert-butyldiethanolamine, tris(2-acetoxyethyl)amine, 2,2',2",2"'-(ethane-1,2-diylbis(azanetriyl))tetraethanol, 2-(dibutylamino)ethanol, and 2,2',2"-nitrilotriethanol; cyclic aliphatic amines such as 1-(tert-Butoxycarbonyl)-4-hydroxypiperidine, tert-butyl 1-pyrrolidinecarboxylate, tert-butyl 2-ethyl-1H-imidazole-1-carboxylate, di-tert-butyl piperazine-1,4-dicarboxylate, and N-(2-acetoxy-ethyl)morpholine; aromatic amines such as pyridine, di-tert-butylpyridine, and pyridinium; linear and cyclic amides and their derivatives such as N,N-bis(2-hydroxyethyl)palmitamide, N,N-diethylacetamide, N 1 ,N 1 ,N 3 ,N 3 -tetrabutylmalonamide, 1-methylazacycloheptan-2-one, 1-allylazacycloheptan-2-one and tert-butyl 1,3-dihydroxy-2-(hydroxymethyl)propan-2-ylcarbamate; ammonium salts such as quaternary ammonium salts of sulfonates, sulfamates, carboxylates and phosphonates; imines such as primary and secondary aldimines and ketimines; diazines such as optionally substituted pyrazines, piperazines, and phenazines; diazoles such as optionally substituted pyrazoles, thiadiazoles and imidazoles; and optionally substituted pyrrolidones such as 2-pyrrolidone and cyclohexylpyrrolidine.

[0171] Exemplary surfactants include fluorinated and non-fluorinated surfactants and can be ionic or non-ionic, with non-ionic surfactants being preferred. Exemplary fluorinated non-ionic surfactants include perfluorinated C4 surfactants such as FC-4430 and FC-4432 surfactants available from 3M Corporation; and fluorodiols such as POLYFOX PF-636, PF-6320, PF-656, and PF-6520 fluorosurfactants from Omnova. In one aspect, the photoresist composition further includes a surfactant polymer comprising fluorinated repeating units.

[0172] Acid-sensitive polymers and other polymers as described herein can be prepared using any suitable method in the art. For example, one or more monomers corresponding to the repeating units described herein can be combined or fed separately using suitable one or more solvents and initiators and polymerized in a reactor. For example, polymers and acid-sensitive polymers can be obtained by polymerization of the corresponding monomers under any suitable conditions, such as by heating at an effective temperature, irradiating with actinic radiation at an effective wavelength, or a combination thereof.

[0173] A patterning method using the photoresist composition of the present invention will now be described. Suitable substrates on which the photoresist composition can be applied include electronic device substrates. A wide variety of electronic device substrates can be used in the present invention, such as semiconductor wafers; polycrystalline silicon substrates; packaging substrates, such as multi-chip modules; flat panel display substrates; substrates for light-emitting diodes (LEDs) including organic light-emitting diodes (OLEDs); etc., with semiconductor wafers being typical. Such substrates are typically made of one or more of silicon, polycrystalline silicon, silicon oxide, silicon nitride, silicon oxynitride, silicon germanium, gallium arsenide, aluminum, sapphire, tungsten, titanium, titanium-tungsten, nickel, copper, and gold. Suitable substrates can be in the form of wafers, such as those used to manufacture integrated circuits, optical sensors, flat panel displays, integrated optical circuits, and LEDs. Such substrates can be of any suitable size. Typical wafer substrate diameters are 200 to 300 millimeters (mm), although wafers with smaller and larger diameters can be appropriately used according to the present invention. The substrate can include one or more layers or structures, which can optionally include an active or operable portion of the device being formed.

[0174] Typically, prior to coating the photoresist composition of the present invention, one or more photoresist layers, such as a hard mask layer (e.g., spin-on carbon (SOC), amorphous carbon, or a metal hard mask layer), a CVD layer (e.g., a silicon nitride (SiN), silicon oxide (SiO), or silicon oxynitride (SiON) layer), an organic or inorganic underlayer, or a combination thereof, are provided on the upper surface of the substrate. Such layers, together with the overcoated photoresist layer, form a photoresist material stack.

[0175] Optionally, an adhesion promoter layer can be applied to the substrate surface before applying the photoresist composition. If an adhesion promoter is desired, any suitable adhesion promoter for the polymer film can be used, such as a silane, typically an organosilane such as trimethoxyvinylsilane, triethoxyvinylsilane, hexamethyldisilazane, or an aminosilane coupling agent such as gamma-aminopropyltriethoxysilane. Particularly suitable adhesion promoters include those sold under the names AP 3000, AP 8000, and AP 9000S available from DuPont Electronics & Imaging (Marlborough, Massachusetts).

[0176] Can be by any suitable method, comprise that spin coating, spraying, dip coating, scraper etc. photoresist composition is coated on substrate.For example, applying photoresist layer can be by using coating track in solvent spin coating photoresist to complete, and wherein photoresist is distributed on the wafer of rotation.In the distribution process, wafer typically with up to 4,000 revs / min (rpm), for example 200 to 3,000rpm, for example 1,000 to 2, the speed rotation time of 500rpm to obtain the photoresist composition layer on substrate.It will be appreciated by those skilled in the art that the thickness of the layer through coating can be regulated by changing the solid content of rotational speed and / or composition.The photoresist layer formed by composition of the present invention typically has 10 to 200 nanometers (nm), preferably 15 to 100nm and more preferably 20 to 60nm dry layer thickness.

[0177] Next, the photoresist composition is typically soft-baked to minimize the solvent content in the layer, thereby forming a tack-free coating and improving the adhesion of the layer to the substrate. Soft baking is carried out, for example, on a hot plate or in an oven, where a hot plate is typical. The soft baking temperature and time will depend on, for example, specific photoresist composition and thickness. The soft baking temperature is typically 90° C. to 170° C., for example, 110° C. to 150° C. The soft baking time is typically 10 seconds to 20 minutes, for example, 1 minute to 10 minutes or 1 minute to 5 minutes. One of ordinary skill in the art can easily determine the heating time based on the composition of the composition.

[0178] Next, the photoresist layer is patterned and exposed to activating radiation to produce solubility difference between exposed area and unexposed area. The photoresist composition mentioned herein is exposed to the radiation that activates the composition and shows that radiation can form a latent image in the photoresist composition. Exposure is typically carried out by a patterned photomask, and the photomask has optically transparent areas and optically opaque areas corresponding to the resist layer area to be exposed and the unexposed resist layer area respectively. Alternatively, this exposure can be carried out in a direct write method without a photomask, and the direct write method is typically used for electron beam lithography. Activating radiation typically has a wavelength of sub-400nm, sub-300nm or sub-200nm, wherein preferably a wavelength of 248nm (KrF), 193nm (ArF) and 13.5nm (extreme ultraviolet, EUV) or electron beam lithography. These methods can be used for immersion or dry (non-immersion) lithography. The exposure energy is typically 1 to 200 mJ / cm2. 2 ), preferably 10 to 100 mJ / cm 2 and more preferably 20 to 50 mJ / cm 2 , depending on the exposure tool and the components of the photoresist composition. In some aspects, the activating radiation is EUV at a wavelength of 13.5 nm.

[0179] After exposing the photoresist layer, a post-exposure bake (PEB) of the exposed photoresist layer is performed. PEB can be performed, for example, on a hot plate or in an oven, with a hot plate being typical. The conditions for PEB will depend, for example, on the specific photoresist composition and layer thickness. PEB is typically performed at a temperature of 80°C to 150°C and for a time of 30 to 120 seconds. A latent image defined by polarity-switched regions (exposed regions) and polarity-unswitched regions (unexposed regions) is formed in the photoresist.

[0180] Then, the exposed photoresist layer is developed with a suitable developer to selectively remove those regions of the layer that are soluble in the developer while retaining insoluble regions, to form the photoresist pattern relief image of resulting. In the case of a positive tone development (PTD) process, the exposed regions of the photoresist layer are removed during development and unexposed regions are retained. On the contrary, in a negative tone development (NTD) process, the exposed regions of the photoresist layer are retained during development and unexposed regions are removed. The application of the developer can be completed by any suitable method, as described above for the application of photoresist compositions, wherein spin coating is typical. The developing time is the time period for effectively removing the soluble regions of the photoresist, wherein typically 5 to 60 seconds. Development is typically carried out at room temperature.

[0181] Suitable developers for the PTD process include aqueous alkaline developers, such as quaternary ammonium hydroxide solutions, such as tetramethylammonium hydroxide (TMAH) (preferably 0.26 standard (N) TMAH), tetraethylammonium hydroxide, tetrabutylammonium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, etc. Suitable developers for the NTD process are based on organic solvents, meaning that the cumulative content of organic solvents in the developer is 50 wt% or more, typically 95 wt% or more, 95 wt% or more, 98 wt% or more, or 100 wt% based on the total weight of the developer. Suitable organic solvents for NTD developers include, for example, those selected from ketones, esters, ethers, hydrocarbons, and mixtures thereof. The developer is typically 2-heptanone or n-butyl acetate.

[0182] A coated substrate can be formed from the photoresist composition of the present invention. Such a coated substrate comprises: (a) a substrate having one or more layers to be patterned on its surface; and (b) a photoresist composition layer on the one or more layers to be patterned.

[0183] The photoresist pattern can be used as, for example, an etching mask, so that the pattern is transferred to one or more sequentially arranged lower layers by known etching techniques, typically dry etching (such as reactive ion etching). The photoresist pattern can be, for example, used to transfer the pattern to an underlying hard mask layer, which is then used as an etching mask for transferring the pattern to one or more layers below the hard mask layer. If the photoresist pattern does not have loss during pattern transfer, it can be removed from substrate by known technology (such as oxygen plasma ashing or wet stripping process). When used for one or more such patterning processes, the photoresist composition can be used to manufacture semiconductor devices, such as storage devices, processor chips (CPUs), graphics chips, optoelectronic chips, LEDs, OLEDs and other electronic devices.

[0184] The present invention is further illustrated by the following examples.

[0185] Examples

[0186] Synthesis example. Synthesis reactions were carried out under normal pressure. All chemicals were used as received from the supplier and were not further purified. Nuclear magnetic resonance (NMR) spectra of the compounds were obtained at 500 and 600 MHz. Chemical shifts (δ) were reported in parts per million (ppm) relative to the residual signal of internal deuterated acetone or deuterated chloroform. Signal multiplicity was reported as singlet (s), doublet (d), triplet (t), multiplet (m), doublet (dd), doublet (dt), triplet (tt) or broad singlet (br), and the number of atoms corresponding to the signal was further clarified.

[0187] Synthesis of 2-furyl(phenyl)iodonium tosylate (1): A round-bottom flask (RBF) equipped with a stir bar and a rubber septum was charged with a dispersion of Koser's reagent [hydroxy(tosyloxy)iodobenzene] (1.0 g, 2.5 mmol) in 20 mL of dichloromethane (DCM). To this dispersion was added 2-furylboronic acid (0.28 g, 2.55 mmol), and the resulting contents were stirred at room temperature (23° C.-25° C.) for 16 hours. After 2 hours, a white precipitate was observed to form, and this material was identified as pure compound 1. The solid was filtered and washed with methyl tert-butyl ether (MTBE) to give 0.7 g of the desired compound, which was used in the next step without further purification.

[0188]

[0189] Synthesis of 2-furyl (phenyl) iodonium 1,1,2,2-tetrafluoro-(3-hydroxyadamantane-1-carbonyl) oxy) butane-1-sulfonate (2): A 100 mL RBF equipped with a stirring bar and a rubber gasket was charged with a solution of 2-furyl (phenyl) iodonium tosylate (1) (0.5 g, 1.1 mmol), compound (i-1) (2.6 g, 6.1 mmol), DCM (20 mL) and water (20 mL). These contents were vigorously stirred at room temperature (23° C.-25° C.) for 16 hours to mix the two-phase combination. The organic layer was then separated from the aqueous layer and extracted with deionized water (15 mL×3 times). The solvent was evaporated and precipitated from MTBE to give 0.4 g of the final compound (2) as a colorless oil (yield 54%). 1 H-NMR (600MHz acetone-d6, δ, ppm): 8.28 (d, 2H), 8.00 (dd, 1H), 7.74 (t, 1H), 7.68 (dd, 1H), 7 .60(t,2H),6.73(dd,1H),4.29(t,2H),2.61(m,2H),2.18(br,2H),1.80-1.55(m,12H); 13 C-NMR (150 MHz acetone-d6, δ, ppm): 175.6, 152.2, 134.9, 132.6, 132.1, 126.5, 117.3, 114.1, 110.3, 66.9, 57.1, 46.3, 44.3, 43.7, 37.6, 35.0, 31.9, 31.7, 30.3, 29.8; 19 F-NMR (600 MHz acetone-d6δ, ppm): -112.4 (m, 2F), -119.2 (m, 2F).

[0190]

[0191] Synthesis of 2-benzofuranyl (phenyl) iodonium toluenesulfonate (3): In a 250 mL RBF equipped with a stirring rod and rubber gasket, benzofuran boronic acid (6.0 g, 0.0372 mol), 14.5 g of Koser's reagent (0.037 mol) and 50 mL of DCM were loaded. The reaction mixture was stirred for 2 hours, after which a white precipitate was observed to have formed. In the reaction mixture, MTBE was added and the resulting precipitate was filtered and washed with another 50 mL of MTBE. The precipitate was dried under vacuum to give 8.0 g of a white solid which was used in the next step without further purification.

[0192]

[0193] Synthesis of 2-benzofuranyl (phenyl) iodonium 1,1,2,2-tetrafluoro-(3-hydroxyadamantane-1-carbonyl) oxy) butane-1-sulfonate (4): A 200 mL RBF equipped with a stirring bar and a rubber gasket was charged with 2-benzofuranyl (phenyl) iodonium toluenesulfonate (3) (5.0 g, 10 mmol), compound (i-1) (6.5 g, 15 mmol), dichloromethane (20 mL) and water (20 mL). The resulting mixture was stirred at room temperature (23° C.-25° C.) for 24 hours. The organic phase was separated from the aqueous phase and DCM was subsequently removed from the organic phase under vacuum. Final compound (4) was obtained by precipitation with DCM and MTBE to obtain 5.0 g (67%) of a white solid. 1 H-NMR(500MHzδ,ppm):8.08(d,2H),7.73(s,1H),7.67(d,1H),7.59(t,1H),7.53(d,1H),7. 45(m,3H),7.33(t,1H),4.24(t,2H),2.54-2.45(m,2H),2.23(br,2H),1.82-1.56(m,14H); 13 C-NMR (125 MHz CDCl 3, δ,ppm):176.3,158.8,134.9,132.6,132.3,127.9,127.2,124.7,122.6,12 2.4,117.1,115.3,111.9,68.6,57.4,46.30,44.34,37.6,35.1,31.6,30.3; 19 F-NMR (500MHz-CDCl3δ, ppm): -112.1 (t, 2F), -117.7 (s, 2F).

[0194]

[0195] The chemical structures of the polymers used in Examples and Comparative Examples are shown below. The acid-sensitive polymer P1 and the embedded barrier layer (EBL) F1 were prepared using methods generally available in the art.

[0196]

[0197] The chemical structures of the photoactive compounds C1, 2, and 4 and the quencher compound D1 used in the Examples and Comparative Examples are shown below.

[0198]

[0199] Compounds C1 and D1 were purchased from commercial sources and used as received.Solvents propylene glycol methyl ether acetate (S1) and methyl-2-hydroxyisobutyrate (S2) were used as received without further purification.

[0200] Photoresist Formulation. A photoresist composition was prepared by dissolving the solid components in a solvent using the materials and amounts listed in Table 1. The resulting mixture, prepared in a ratio of 14-30 g, was shaken on a mechanical shaker for 3 to 24 hours and then filtered through a PTFE disk filter with a pore size of 0.2 μm. The amounts of PAG, quencher, and EBL are reported as wt% based on total solids.

[0201] Table 1

[0202]

[0203] *E 尺寸 (mJ / cm 2 ) is for a 1:1 line / space (L / S) pattern as described below.

[0204] Example 1: Immersion patterning. Immersion lithography was performed using a TEL Lithius 300mm wafer track and an ASML 1900i immersion scanner with 1.3NA, 0.86 / 0.61 inner / outer σ and 35Y polarization dipole illumination. The wafers used for the lithography test were coated with AR40A TM The bottom anti-reflective coating (BARC) was cured at 205°C for 60 seconds to obtain Then in AR40A TM AR104 BARC is deposited on the layer TM and cured at 175°C for 60 seconds to obtain the top of the double BARC stack. The photoresist composition was then coated on the double BARC stack and baked at 90°C for 60 seconds to obtain Resist film. The wafer was exposed using a focus exposure matrix with a 55nm / 110nm pitch and a 43nm / 86nm pitch 1:1 line / space (L / S) pattern as the target and subjected to PEB at 95°C for 60 seconds. After PEB, the wafer was developed in 0.26N TMAH solution for 12 seconds, rinsed with deionized water, and spin-dried. Scanning electron microscopy (SEM) was performed to collect images and the printed patterns were analyzed using a Hitachi CG4000 CD-SEM. 尺寸 Values are in mJ / cm 2 As shown in Table 1, the photoresist compositions of the present invention comprising PAG 2 or PAG 4 achieve lower E values at both 1:1 L / S of 55 nm and 43 nm compared to the comparative photoresist composition comprising PAG C1. 尺寸 , indicating that PAGC1 has a faster photosensitivity compared to the control.

[0205] Calculated EUV Transmittance. The effect of using furan-substituted iodonium PAG compounds on film absorption under EUV radiation was evaluated by calculating the absorbance at this wavelength. The calculated transmittances of two exemplary furan-substituted iodonium cations and their respective phenyl and naphthyl analogs at the EUV exposure wavelength (13.5 nm) are reported in Table 2. The transmittance values were obtained from the Center for X-Ray Optics at Lawrence Berkeley National Laboratory website (https: / / henke.lbl.gov / optical_constants / ) by entering the calculated composition formula and assuming a film density of 1.20 g / cm 3 The calculation is based on a film thickness of 100 nm.

[0206] Table 2

[0207]

[0208] The structures of cation A (A), cation B (B), comparative cation A (A') and comparative cation B (B') are as follows:

[0209]

[0210] As can be seen from Table 2, the inventive PAG cations A and B achieve lower calculated transmittance at 13.5 nm than the comparative PAG cations A' and B'. The resulting increased EUV absorption for PAG cations A and B is desirable for improving EUV photoresist performance.

[0211] While the disclosure has been described in connection with what are presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A photoresist composition comprising: an acid-sensitive polymer comprising repeating units having an acid-labile group; An iodonium salt comprising an anion and a cation, the cation comprising a single iodonium cation, the iodonium salt having formula (1): in, Z - is an organic anion comprising a group selected from the group consisting of a sulfonate, a methide anion, a sulfonamide anion, a sulfonylimide anion, a sulfamate, a phenoxide, or a carboxylate; Ar 1 is a substituted or unsubstituted furan heterocycle containing C 4-60 heteroaryl; and R 1 It is C 1-20 Alkyl, C 1-20 Heteroalkyl, C 3-20 Cycloalkyl, C 2-20 Heterocycloalkyl, C 2-20 Alkenyl, C 2-20 Heteroalkenyl, C 6-30 Aryl, C 4-30 Heteroaryl, C 7-20 Arylalkyl, or C 4-20 heteroarylalkyl, each of which is substituted or unsubstituted, wherein the cation optionally comprises an acid labile group, Among them, Ar 1 and R 1 are optionally linked to each other via a single bond or one or more divalent linking groups to form a ring, and wherein the iodonium salt is optionally 1 or covalently bonded to the polymer via its substituents as pendant groups, the iodonium salt optionally being bonded via R 1 or covalently bonded to the polymer via its substituent as a pendant group, or the iodonium salt is optionally bonded via Z - covalently bonded to the polymer as a pendant group; and solvent.

2. The photoresist composition according to claim 1, wherein Ar 1 and R 1 They are linked to each other via a single bond or a divalent linking group to form a ring.

3. The photoresist composition according to claim 1 or 2, wherein Ar 1 Substituted with an acid-labile group, R 1 Substituted with an acid-labile group, or Ar 1 and R 1 Both are independently substituted with an acid-labile group. 4 . The photoresist composition according to claim 1 , further comprising a photoacid generator, wherein the corresponding photoacid of the photoacid generator has a lower pKa than the corresponding photoacid of the iodonium salt.

5. The photoresist composition according to any one of claims 1 to 4, further comprising a photodecomposable quencher, wherein the corresponding photoacid of the photodecomposable quencher has a higher pKa than the corresponding photoacid of the iodonium salt.

6. The photoresist composition according to any one of claims 1 to 5, wherein The acid-sensitive polymer comprises a repeating unit having an aromatic group, wherein the aromatic group is substituted or unsubstituted.

7. The photoresist composition according to any one of claims 1 to 5, wherein The C 4-60 Heteroaryl is in, R 6a 、R 6b 、R 6c 、R 6d 、R 6e and R 6f are each independently a single bond, hydrogen, substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 1-30 Haloalkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 1-30 Heterocycloalkyl, substituted or unsubstituted C 2-30 Alkenyl, substituted or unsubstituted C 2-30 Alkynyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 7-30 Alkylaryl, substituted or unsubstituted C 3-30 Heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, halogen, -OR 61 、-SR 62 , or -NR 63 R 64 , where R 61 to R 64 are each independently hydrogen, or substituted or unsubstituted C 1-30 Alkyl, substituted or unsubstituted C 3-30 Cycloalkyl, substituted or unsubstituted C 2-30 Heterocycloalkyl, substituted or unsubstituted C 6-30 Aryl, substituted or unsubstituted C 7-30 Arylalkyl, substituted or unsubstituted C 3-30 Heteroaryl, or substituted or unsubstituted C 4-30 heteroarylalkyl; R 6a 、R 6b 、R 6c 、R 6d 、R 6e or R 6f One of them is a single bond to the iodonium cation; m is 0 to 6; n is 0 to 6; and x is 1 to 6.

8. The photoresist composition according to any one of claims 1 to 7, wherein The iodonium salt is covalently bonded to the polymer as a pendant group.

9. A pattern forming method comprising: (a) applying a layer of the photoresist composition according to any one of claims 1 to 8 on a substrate; (b) pattern-wise exposing the photoresist composition layer to activating radiation; as well as (c) developing the exposed photoresist composition layer to provide a resist relief image.

10. The pattern forming method according to claim 9, wherein The activating radiation is extreme ultraviolet radiation at a wavelength of 13.5 nanometers.

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