Photoresist composition and pattern forming method
By introducing non-solvent-based, alkali-insoluble base materials and non-polymeric ionic photoacid generators into the photoresist composition, and utilizing intramolecular non-covalent bonds to stabilize sulfonate anions, the problem of low acid dissociation constant in existing photoresist compositions is solved, thereby improving photosensitivity and lithography properties, making it suitable for high-resolution lithography in semiconductor manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 杜邦电子材料国际有限责任公司
- Filing Date
- 2024-08-16
- Publication Date
- 2026-05-01
AI Technical Summary
Among existing photoresist compositions, fluorinated photoacid generating compounds have high acid dissociation constants but are not environmentally friendly. Furthermore, fluorine-free alternatives such as p-toluenesulfonate and camphorsulfonate anions have low acid dissociation constants, which limits their application in generating high-intensity photoacids.
A photoresist composition based on non-solvent, alkali-insoluble base materials is used. It contains non-polymeric ionic photoacid generating compounds and uses iodonium or sulfonium cations and anions with specific structures to stabilize sulfonate anions through intramolecular non-covalent bonds, thereby improving acid dissociation ability.
High-acidity photo-acid generation was achieved, improving photosensitivity and lithography characteristics, such as sizing energy, exposure latitude, and linewidth roughness, to meet the requirements of high-resolution lithography, while reducing the impact on the environment.
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Figure CN121969993A_ABST
Abstract
Description
Cross-Reference to Applications Related to Photoresist Compositions and Patterning Methods This application claims priority and benefit to U.S. Provisional Application Serial No. 65 / 533,270, filed August 17, 2023, the entire contents of which are incorporated herein by reference. Technical Field
[0001] This invention relates to photoresist compositions and methods for patterning using such photoresist compositions. The invention finds particular applicability in photolithography applications within the semiconductor manufacturing industry. Background Technology
[0002] Photoresist compositions are photosensitive materials used to transfer patterns onto one or more underlying layers (such as metal, semiconductor, or dielectric layers) disposed on a substrate. Positively chemically enhanced photoresist compositions are commonly used for high-resolution processing. Such photoresist compositions typically include a polymer with acid-indestabilized groups and a photoacid generator (PAG). The layer of the photoresist composition is exposed to activating radiation in a patterned manner, and the PAG generates acid in the exposed areas. During post-exposure baking, the acid causes the acid-indestabilized groups of the polymer to break down and results in a polarity reversal of the polymer in the exposed areas. This creates a difference in solubility properties between the exposed and unexposed areas of the photoresist layer in the developer solution. During positive development (PTD), the exposed areas of the photoresist layer become soluble in the developer (typically an aqueous alkaline developer) and are removed from the substrate surface, while the unexposed areas remain on the substrate to form a positive relief image. Alternatively, during negative development (NTD), unexposed areas of the photoresist layer can be removed using an organic solvent developer (typically n-butyl acetate), while the exposed areas remain on the substrate to form a negative relief image. The resulting relief image allows for selective processing of the substrate.
[0003] A key property of photoresist compositions that can directly impact semiconductor manufacturing costs is photosensitivity, i.e., sensitivity to activation radiation generated by exposure tools, where higher sensitivity corresponds to higher process yields for a given feature size. To increase photosensitivity, it is desirable for PAGs to generate sufficiently strong acids to cleave acid-indestabilized groups on the polymer. For this purpose, ionic PAG compounds are typically formed with a photoactive cation and an anion containing a fluorinated sulfonate group, wherein a fluorine atom and / or a fluoroalkyl group is adjacent to the sulfonate group, typically acting as a substituent bonded to one or more alkylene carbon atoms bonded to the sulfonate anion group. Upon exposure to activation radiation, the photoactive cation undergoes a series of photochemical and chemical processes leading to the formation of fluorinated sulfonic acid. While some fluorinated PAGs in this class allow for high-acidity photoacids, the semiconductor manufacturing industry and government regulatory agencies are increasingly interested in replacing them with more sustainable alternatives.
[0004] Existing examples of fluorine-free PAGs include p-toluenesulfonate anions and camphorsulfonate anions. However, these anions have relatively low acid dissociation constants (e.g., about 18 orders of magnitude smaller than that of tris(trifluoromethylsulfonyl)methane), which limits their usefulness in photoresists requiring higher-strength photoacids. Therefore, it would be desirable to have photoresist compositions containing an ionic photoacid generating compound that produces a sulfonic acid of sufficient strength to increase acidity without relying on specific fluorine substitution.
[0005] There is a persistent need to address one or more problems related to the prior art in photoresist compositions, and patterning methods using such photoresist compositions. Summary of the Invention
[0006] On one hand, a photoresist composition is provided, comprising one or more non-solvent-based, alkali-insoluble base materials present in an amount greater than 50% by weight of the total solids of the photoresist composition; and a non-polymeric ionic photoacid generating compound comprising an anion and an iodonium or sulfonium cation, wherein the anion is represented by formula (1): (1) Wherein, in equation (1), Ar 1 Is it a single-ring or multi-ring C? 3-60 Aromatic groups; each L 1 Independently, it is a single bond or one or more divalent connecting groups, wherein L 1 Fluorine-free; each R 1 C is either substituted or unsubstituted independently. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Cycloalkenyl, substituted or unsubstituted C 3-30 Heterocyclic alkyl, 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 6-30 aryloxy, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 Alkyl heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, or substituted or unsubstituted C 3-30 Heteroaryl groups; wherein at least one R 1 Replaced by halogens; each R 1 Optionally, it may further comprise one or more divalent linking groups as part of its structure; each Z 1 Independently contains an anionic stabilizing group, wherein at least one Z 1It is configured to form an intramolecular noncovalent bond with a sulfonate anion group to form a ring with 5 to 8 atoms, wherein Z 1 Independently selected from -OH, -C(O)OH, -SH, -C(O)SH, -NHS(O)2R 2 -S(O)2R 2 -S(O)2NHS(O)2R 2 -CH (=NOH), or -B (R) 3 )2; Each Z 1 Optionally, it may further comprise one or more divalent linking groups as part of its structure; each R 2 Independently selected from fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 heteroaryl; each R 3 Independently selected from hydrogen, fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 heteroaryl; two R 1 Together with Ar 1 A fused ring is formed, wherein the fused ring optionally further comprises one or more divalent linking groups as part of its structure; and a Z 1 And an R 1 Together with Ar 1 A fused ring is formed, wherein the fused ring optionally further comprises one or more divalent linking groups as part of its structure, each a being independently 1 or 2; b being an integer from 1 to 4; and c being an integer from 1 to 3; and a solvent.
[0007] On the other hand, a patterning method is provided, which includes applying a layer of photoresist composition onto a substrate to provide a photoresist composition layer; exposing the photoresist composition layer in a patterned manner to activation radiation to provide an exposed photoresist composition layer; and developing the exposed photoresist composition layer to provide a resist relief image. Detailed Implementation
[0008] Reference will now be made in detail to exemplary embodiments, examples of which are shown in this specification. In this respect, exemplary embodiments of the invention may take different forms and should not be construed as limited to the description herein. Therefore, exemplary embodiments are described below only by reference to the accompanying drawings to explain 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 the list of elements, it modifies the entire list of elements and does not modify any individual element in the list.
[0009] As used herein, the terms “a / an” and “the” do not indicate a limitation of quantity and are to be construed as including both the singular and plural unless otherwise indicated herein or clearly contradicted by the context. Unless otherwise explicitly stated, “or” means “and / or”. The modifier “about” used in conjunction with quantity includes the stated value and has the meaning specified by the context (e.g., including the degree of error associated with a particular quantity of measurement). The full scope disclosed herein includes endpoints, and these endpoints can be independently combined with each other. The suffix “(s)” is intended to include both the singular and plural of the term it modifies, thereby including at least one of the terms. “Optional” or “optionally” means that an event or situation subsequently described may or may not occur, and the description includes both the occurrence and non-occurrence of the event. The terms “first,” “second,” and similar terms herein do not indicate order, quantity, or importance, but are used to distinguish one element from another. When an element is referred to as being “on” another element, it may be in direct contact with that other element or interposed between the elements. In contrast, there is no inserted element when an element is described as being "directly on" another element. It should be understood that the components, elements, limitations, and / or features of the described aspects can be combined in any suitable manner within the aspects.
[0010] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will be further understood that terms (such as those defined in common dictionaries) shall be interpreted as having the same meaning as they have in the relevant field and in the context of this disclosure, and shall not be construed as having an idealized or overly formal meaning unless expressly defined herein.
[0011] As used herein, "photochemical rays" or "radiation" refers to, for example, the bright-line spectrum of a mercury lamp, far-ultraviolet light represented by an excimer laser, extreme ultraviolet light (EUV light), X-rays, particle rays (such as electron beams and ion beams), etc. Additionally, in this invention, "light" refers to photochemical rays or radiation. A krypton fluoride laser (KrF laser) is a specific type of excimer laser, sometimes called an excimer complex laser. "Excimer" is an abbreviation for "excited dimer," and "excimer complex" is an abbreviation for "excited complex." Excimer lasers use a mixture of rare gases (argon, krypton, or xenon) and halogen gases (fluorine or chlorine) that, under suitable electrical stimulation and high voltage conditions, emit coherent stimulated emission (laser) in the ultraviolet range. Furthermore, unless otherwise stated, "exposure" in this specification includes not only exposure through a mercury lamp, far-ultraviolet light represented by an excimer laser, X-rays, extreme ultraviolet light (EUV light), etc., but also writing with particle rays (such as electron beams and ion beams).
[0012] As used herein, the term "hydrocarbon" refers to an organic compound or group having at least one carbon atom and at least one hydrogen atom; "alkyl" refers to a straight-chain or branched saturated hydrocarbon group having a specified number of carbon atoms and 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 group (-OH); "alkoxy" refers to "alkyl-O-"; "carboxyl" and "carboxylic acid" refer to groups having the formula "-C(O)-OH"; "cycloalkyl" refers to a group having all ring members... "A" is a monovalent group of one or more saturated rings of carbon; "cycloalkylene" refers to a cycloalkyl group with a valence of 2; "alkenyl" refers to a straight-chain or branched monovalent hydrocarbon group with at least one carbon-carbon double bond; "alkenyloxy" refers to "alkenyl-O-"; "alkenylene" refers to an alkenyl group with a valence of 2; "cycloalkenyl" refers to a non-aromatic cyclic divalent hydrocarbon group with at least three carbon atoms and at least one carbon-carbon double bond; "alkynyl" refers to a monovalent hydrocarbon group with at least one carbon-carbon triple bond; the term "aromatic group" refers to a group that satisfies Hückel's rule (4n+2). A monocyclic or polycyclic aromatic ring system containing carbon atoms (π electrons); the term "heteroaromatic group" refers to an aromatic group containing one or more heteroatoms selected from N, O, and S (e.g., 1-4 heteroatoms) that replace carbon atoms in the ring; "aryl" refers to a monovalent monocyclic or polycyclic aromatic ring system in which each ring member is carbon and may include a group having an aromatic ring fused to at least one cycloalkyl or heterocyclic alkyl ring; "arylene" refers to an aryl group having a valence of 2; "alkylaryl" refers to an aryl group that has been substituted by an alkyl group; "arylalkyl" refers to an alkyl group that has been substituted by an aryl group; "aryloxy" refers to "aryl-O-"; and "arylthio" refers to "aryl-S-".
[0013] The prefix "hetero" indicates that a compound or group contains at least one member (e.g., 1, 2, 3, or 4 or more heteroatoms) as a heteroatom replacing a carbon atom, wherein one or more heteroatoms are each independently N, O, S, Si, or P; "heteroatom-containing group" refers to a substituent group containing at least one heteroatom; "heteroalkyl" refers to an alkyl group having at least one heteroatom replacing a carbon atom; "heterocyclic alkyl" refers to a cycloalkyl group having 1-4 heteroatoms as a ring member replacing a carbon atom; "heterocyclic alkyl" refers to a cycloalkyl group having 2... Heterocyclic alkyl groups with a valence of 1-4 heteroatoms (if monocyclic), 1-6 heteroatoms (if bicyclic), or 1-9 heteroatoms (if tricyclic) are aromatic 4-8 membered monocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic systems, each heteroatom being independently selected from N, O, S, Si, or P (e.g., carbon atom and 1-3, 1-6, or 1-9 N, O, or S heteroatoms, respectively, if monocyclic, bicyclic, or tricyclic). Examples of heteroaryl groups include pyridyl, furanyl (furyl or furanyl), imidazolyl, benzimidazolyl, pyrimidinyl, thiophenyl or thienyl, quinolinyl, indolyl, thiazolyl, etc.; and "hybrid aryl" refers to a heteroaryl group with a valence of 2.
[0014] The term "halogen" refers to a monovalent substituent of fluorine (fluoro), chlorine (chloro), bromine (bromo), or iodine (iodo). The prefix "halogenated" refers to a group containing one or more of the fluorine, chlorine, bromine, or iodine substituents that replace a hydrogen atom. Combinations of halogen groups (e.g., bromine and fluorine) or only fluorine groups may be present. For example, the term "halogenated alkyl" refers to an alkyl group substituted with one or more halogens. As used herein, "substituted C" refers to an alkyl group substituted with one or more halogens. 1-8 "Halogenated alkyl" refers to a C that has been substituted with at least one halogen. 1-8 Alkyl groups, and further substituted by one or more other substituents that are not halogens. It should be understood that substitution of a group with a halogen atom should not be considered a heteroatom-containing group, because the halogen atom does not substitute for a carbon atom.
[0015] Unless otherwise explicitly stated, each of the aforementioned substituents may be optionally substituted. The term “optionally substituted” means substituted or unsubstituted. “Substituted” means that at least one hydrogen atom of a chemical structure or group is substituted by another terminal substituent, typically monovalent, provided that the valence of the specified atom is not exceeded. When the substituent is oxo (i.e., O), the two twin hydrogen atoms on the carbon atom are replaced by a terminal oxo group. Further note that the oxo group is bonded to carbon via a double bond to form a carbonyl group (C=O), which is represented herein as -C(O)-. Combinations of substituents or variables are permitted. Exemplary substituents that may be present at the “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, alkylacyl (such as C 2-6 Alkyl groups, such as acyl groups, formyl groups (-C(O)H), carboxylic acids or their alkali metal or ammonium salts; esters (including acrylates, methacrylates and lactones), such as C 2-6 Alkyl esters (-C(O)O-alkyl or -OC(O)-alkyl) and C 7-13 Aryl esters (-C(O)O-aryl or -OC(O)-aryl); amide groups (-C(O)NR2, where R is hydrogen or C). 1-6 alkyl), formamido (-CH2C(O)NR2, where R is hydrogen or C 1-6 Alkyl groups, halogens, mercapto groups (-SH), C 1-6 Alkylthio (-S-alkyl), thiocyano (-SCN), C 1-6 Alkyl, C 2-6 alkenyl, C 2-6 alkynyl group, C 1-6 Haloalkyl, C 1-9 Alkoxy, C 1-6 Halogenated alkoxy groups, C 3-12 cycloalkyl, C 5-18 Cycloalkenyl, C 2-18 Heterocyclic alkenyl groups, C groups having at least one aromatic ring 6-12 Aryl (e.g., phenyl, biphenyl, naphthyl, etc., each ring being substituted or unsubstituted aromatic), having 1 to 3 individual or fused rings and 6 to 18 ring carbon atoms, C 7-19 Arylalkyl, arylalkoxy having 1 to 3 individual or fused rings and 6 to 18 ring carbon atoms, C 7-12 alkylaryl, C 3-12 Heterocyclic alkyl, C 3-12 heteroaryl, C 1-6 alkylsulfonyl (-S(O)2-alkyl), C 6-12Arylsulfonyl (-S(O)2-aryl) or toluenesulfonyl (CH3C6H4SO2-).
[0016] As used herein, unless otherwise defined, "divalent linker" refers to -O-, -S-, -Te-, -Se-, -C(O)-, C(O)O-, and -N(R)-. ’ )-、-C(O)N(R ’ -, -S(O)-, -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 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 A divalent group of heteroaryl or a combination thereof, wherein each R ’ It is independently hydrogen, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Heteroaryl groups. Typically, the divalent linking groups include -O-, -S-, -C(O)-, -C(O)O-, -N(R')-, and -C(O)N(R). ' -, -S(O)-, -S(O)2-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 One or more of heteroaryl groups or combinations thereof, wherein R' is hydrogen, substituted or unsubstituted C. 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Heteroaryl groups. More typically, the divalent linking groups include -O-, -C(O)-, -C(O)O-, and -N(R-). ' -, -C(O)N(R')-, substituted or unsubstituted C 1-10 Alkylene, substituted or unsubstituted C 3-10 Cycloalkylene, substituted or unsubstituted C 3-10 Heterocyclic alkyl, substituted or unsubstituted C 6-10 aryl, substituted or unsubstituted C 3-10At least one of heteroaryl groups or combinations thereof, wherein R is hydrogen, substituted or unsubstituted C. 1-10 Alkyl, substituted or unsubstituted C 1-10 Heteroalkyl, substituted or unsubstituted C 6-10 aryl, or substituted or unsubstituted C 3-10 Mixed aromatic compounds.
[0017] As used herein, an "acid-indestructible group" refers to a group in which a bond is cleaved by the action of an acid, optionally and typically by thermal treatment, resulting in the formation of a polar group, such as a carboxylic acid or alcohol group. In some cases, the acid-indestructible group can form on a polymer and optionally and typically detach from the polymer along with the portion attached to the cleaved bond. In other systems, nonpolymerized compounds may contain an acid-indestructible group that can be cleaved by the action of an acid, resulting in the formation of a polar group, such as a carboxylic acid or alcohol group, on the cleaved portion of the nonpolymerized compound. Such acids are typically photogenerated acids in cases where bond cleavage occurs during post-exposure baking (PEB); however, the examples are not limited thereto, and such acids may, for example, be thermally generated. Suitable acid-indestructible groups include, for example, tertiary alkyl ester groups, secondary or tertiary ester groups having an aryl group, secondary or tertiary ester groups having a combination of alkyl and aryl groups, tertiary alkoxy groups, acetal groups, or ketal groups. Acid-indestructible groups are also commonly referred to in the art as "acid-cleavable groups," "acid-cleavable protecting groups," "acid-indestructible protecting groups," "acid-leaving groups," "acid-decomposable groups," and "acid-sensitive groups."
[0018] The sensitivity of photoresist performance is generally correlated with the final device production yield. In particular, high-resolution lithography techniques (such as 193 nm lithography (ArF)) tend to struggle with photoresists possessing optimal sensitivity. To achieve good sensitivity, many photoresists employ photoacid generators (PAGs) containing anions belonging to the sulfonate class coupled to polymers containing low-activation-energy leaving groups (e.g., acetals or acetal-esters). Over the past decade, numerous sulfonate derivatives have been developed for this purpose, with fluorinated sulfonates being a prime example. These compounds, which exhibit excellent performance in lithography due to their extremely high acidity, are being considered worldwide as alternatives in support of more sustainable alternatives. The need for PAG anions with good acidity and better sustainability remains.
[0019] The inventors of this invention have discovered a photoacid generator comprising an anionic core containing an aromatic group substituted with: (i) at least one group comprising a halogen atom; (ii) a sulfonate anionic group; and (iii) an anionic stabilizing group configured to stabilize the sulfonate anionic group with an intramolecular noncovalent bond. In other words, the anionic stabilizing group is configured to form an intramolecular noncovalent bond with the sulfonate anionic group. For example, without being bound by theory, the anionic stabilizing group can form an intramolecular noncovalent bond with the sulfonate anionic group, or, for example, the anionic stabilizing group can form an intramolecular noncovalent bond with the sulfonate anionic group. In some embodiments, the intramolecular noncovalent bond can be formed in situ, such as when a nonpolymeric ionic photoacid generator compound is included in a photoresist composition. When used in a photoresist composition, the PAG according to the invention can produce suitable photolithographic properties, such as sizing energy (E). 尺寸 Exposure latitude % (EL%), and / or line width roughness.
[0020] A photoresist composition is provided comprising one or more non-solvent-based, alkali-insoluble base materials present in an amount greater than 50 wt% of the total solids of the photoresist composition, and a non-polymeric ionic photoacid generating compound comprising an anion and an iodonium or sulfonium cation, wherein the anion is represented by formula (1): (1); where b is an integer from 1 to 4, and at least one R 1 The components are halogenated, and the remaining groups are as defined herein; and the solvent. It should be understood that the total solids comprise one or more non-solvent-based insoluble base materials, non-polymeric ionic photoacid generating compounds, and other non-solvent components.
[0021] In equation (1), Ar 1 Is it a single-ring or multi-ring C? 3-60 Aromatic groups. For example, monocyclic or polycyclic carbon groups. 3-60 Aromatic groups can be monocyclic C 3-60 Aromatic groups or polycyclic carbons 6-60 Aromatic groups. In the examples, monocyclic or polycyclic C... 3-60 The aromatic group can be a monocyclic or polycyclic C 6-60 arylene or monocyclic or polycyclic C 3-60 Heteroaryl, typically monocyclic or polycyclic C 6-30 arylene or monocyclic or polycyclic C 3-30 Hybrid aryl.
[0022] It should be understood that when "single-ring or multi-ring C" 6-60When the "aryl" group is polycyclic, the number of carbon atoms is sufficient to make the group chemically feasible. For example, "monocyclic or polycyclic C..." 6-60 "Aryl" can refer to "monocyclic C6 arylene or polycyclic C6 arylene". 10-60 "Arylidene"; or, for example, "monocyclic C6 arylidene or polycyclic C6 arylidene". 10-30 "Aspartic". Similarly, when "monocyclic or polycyclic C..." 3-60 When a "heteroaryl" group is polycyclic, the number of carbon atoms is sufficient to make the group chemically feasible. For example, "monocyclic or polycyclic C..." 3-60 "Hybrid aryl" can refer to "monocyclic C 3-6 Heteroaryl or polycyclic C 5-60 "Hybrid aryl"; or, for example, "monocyclic C". 3-6 Heteroaryl or polycyclic C 5-30 "hybrid aryl".
[0023] Exemplary single-ring or multi-ring C 3-60 Aromatic groups include, but are not limited to, benzene, naphthalene, anthracene, phenanthrene, pyrene, guanidine, benzo[a]phenanthrene, phenanthracene, phenaene, benzo[a]anthracene, dibenzo[a,h]anthracene, or benzo[a]pyrene.
[0024] In equation (1), each L 1 Independently, it is a single bond or one or more divalent connecting groups, wherein L 1 Fluorine-free. In other words, when L... 1 When it is one or more divalent linking groups, then L 1 Fluorine-free. Each of the one or more divalent linking groups may be substituted or unsubstituted. Exemplary divalent linking groups may each be independently selected from -O-, -C(O)-, -C(O)O-, -S-, -S(O)-, -S(O)2-, -N(R ’ -, -C(O)N(R')-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 heteroaryl, or combinations thereof, wherein R ’ It can be hydrogen, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Hybrid aromatics. Typically, L 1 It can be a single bond, or a substituted or unsubstituted C. 1-20 Alkylene, preferably single bond or substituted or unsubstituted C 1-10alkylene, wherein L 1 It does not contain α-carbon atoms of sulfur atoms that are directly covalently bonded to sulfonate anionic groups substituted with fluorine atoms or fluoroalkyl groups.
[0025] In equation (1), each R 1 C is either substituted or unsubstituted independently. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, 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 6-30 aryloxy, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 Alkyl heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, or substituted or unsubstituted C 3-30 Heteroaryl groups, wherein at least one R 1 Replaced by halogens. For example, each R 1 C can be substituted or unsubstituted independently. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Heteroaryl, wherein at least one R 1 Replaced by halogens.
[0026] In some embodiments, at least one R 1 It is the replacement of C 6-30 Aryl or substituted C 7-30 arylalkyl, wherein at least one R 1 Replaced by halogens. For example, at least one R 1 It can be a substitute for C 6-30 Aryl or substituted C 6-10 aryl, wherein at least one R 1 It is replaced by one or more fluorine atoms, one or more iodine atoms, or a combination thereof.
[0027] In equation (1), each R 1Optionally, it may further include one or more divalent linking groups as part of its structure. Each of the one or more divalent linking groups may be substituted or unsubstituted. Exemplary divalent linking groups may be selected from -O-, -C(O)-, -C(O)O-, -S-, -S(O)-, -S(O)2-, -N(R ’ -, -C(O)N(R')-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 heteroaryl, or combinations thereof, wherein R ’ It can be hydrogen, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Mixed aromatic compounds.
[0028] Typically, R 1 It contains one or more divalent linking groups as part of its structure. In some embodiments, R 1 Contains one or more divalent linking groups selected from the following: -O-, -C(O)-, -C(O)O-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 Heteroaryl groups or combinations thereof, preferably wherein R 1 It may contain one or more divalent linking groups selected from the following: -O-, -C(O)-, -C(O)O-, substituted or unsubstituted C 1-30 Alkylenes, or combinations thereof. For example, R 1 The divalent linker can be -O-, -C(O)O-, or -O(CH2). x O-, where x is an integer from 1 to 4.
[0029] In some embodiments, one or more R 1 Each of them may independently include acid-insecure groups, lactone-containing groups, alkali-soluble groups, or combinations thereof as part of their structure.
[0030] In equation (1), each Z 1 Independently contains an anionic stabilizing group, wherein at least one Z 1It is configured to form an intramolecular noncovalent bond with a sulfonate anion group to form a ring with 5 to 8 atoms, wherein Z 1 Independently selected from -OH, -C(O)OH, -SH, -C(O)SH, -NHS(O)2R 2 -S(O)2R 2 -S(O)2NHS(O)2R 2 -CH (=NOH), or -B (R) 3 )2, where R 2 and R 3 Each is as defined herein. Typically, each anionic stabilizing group Z 1 It can be independently selected from -OH, C(O)OH, SH, or -B(OH)2, and preferably has at least one anionic stabilizing group Z. 1 It contains -OH.
[0031] For example, each Z 1 It can be configured to form intramolecular non-covalent bonds with sulfonate anionic groups to form rings with 6 or 7 atoms. It should be understood that when monocyclic or polycyclic C... 3-60 Aromatic group Ar 1 Contains two or more anionic stabilizing groups Z 1 When, the anion stabilizing group Z 1 At least one of them is configured to form an intramolecular noncovalent bond with at least one sulfonate anionic group to form a ring having 5 to 8 atoms.
[0032] As used herein, an "anionic stabilizing group" means any suitable group that can stabilize a sulfonate anionic group via an intramolecular noncovalent bond, as provided herein. Thus, the anionic stabilizing group is configured to form an intramolecular noncovalent bond with the sulfonate anionic group, or, in other words, the anionic stabilizing group is capable of forming an intramolecular noncovalent bond with the sulfonate anionic group. As used herein, "noncovalent bond" can refer to any noncovalent interaction between the anionic stabilizing group and the sulfonate anionic group. As noted above, the noncovalent interaction is intramolecular, wherein the anionic stabilizing group and the sulfonate anionic group are on the same molecule. Exemplary noncovalent interactions include hydrogen bonding or ionic bonding. The anionic stabilizing group can include a group that is a proton. For example, an intramolecular noncovalent bond can be an intramolecular hydrogen bond between a suitable hydrogen atom of the anionic stabilizing group and the sulfonate anionic group. For example, in some embodiments, the anionic stabilizing group may be configured to form an intramolecular hydrogen bond with the sulfonate anionic group, and, for example, in some embodiments, the anionic stabilizing group may form an intramolecular hydrogen bond with the sulfonate anionic group. In some embodiments, intramolecular non-covalent bonding includes dipole-dipole interactions, ion-dipole interactions, or combinations thereof. As used herein, “non-covalent bond” does not include bonding based solely on van der Waals forces.
[0033] In some embodiments, the anionic stabilizing group may have a pKa of 25 or less, typically 20 or less, or 18 or less, and preferably 16 or less.
[0034] In some embodiments, each anion-stabilizing group comprises a group that is a proton. For example, when the anion-stabilizing group is a proton, then each Z 1 It can be independently selected from -OH, -C(O)OH, -SH, -C(O)SH, -NHS(O)2R 2 -S(O)2R 2a -S(O)2NHS(O)2R 2 -CH (=NOH), or -B (R) 3a )2, where each R 2 Independently selected from fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 heteroaryl; each R 2a It is a hydroxyl group; and each R 3a Independently selected from hydrogen, fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30aryl, or substituted or unsubstituted C 3-30 heteroaryl, provided that at least one R 3a It is hydrogen or hydroxyl.
[0035] In equation (1), each Z 1 Optionally, it may further include one or more divalent linking groups as part of its structure. Each of the one or more divalent linking groups may be substituted or unsubstituted. Exemplary divalent linking groups may be selected from -O-, -C(O)-, -C(O)O-, -S-, -S(O)-, -S(O)2-, -N(R ’ -, -C(O)N(R')-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 heteroaryl, or combinations thereof, wherein R ’ It can be hydrogen, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Mixed aromatic compounds. Typically, Z 1 Optionally, it may further include one or more divalent linking groups selected from: -O-, -C(O)-, -C(O)O-, -S(O)-, -S(O)2-, -N(R ’ -, -C(O)N(R')-, substituted or unsubstituted C 1-10 Alkylene, substituted or unsubstituted C 3-10 Cycloalkylene, substituted or unsubstituted C 3-10 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 heteroaryl, or combinations thereof, wherein R ’ It can be hydrogen, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Heteroaryl. In some embodiments, each Z... 1 It can independently exclude divalent linking groups, allowing the anionic stabilizing group to bond directly to Ar. 1 .
[0036] In equation (1), each R 2Independently selected from fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Mixed aromatic compounds.
[0037] In equation (1), each R 3 Independently selected from hydrogen, fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Mixed aromatic compounds.
[0038] In equation (1), the two R 1 Together with Ar 1 A fused ring is formed, wherein the fused ring optionally further comprises one or more divalent linking groups as part of its structure. Each of the one or more divalent linking groups is substituted or unsubstituted, and the fused ring is substituted or unsubstituted.
[0039] In equation (1), a Z 1 And an R 1 Together with Ar 1 A fused ring is formed, wherein the fused ring optionally further comprises one or more divalent linking groups as part of its structure. Each of the one or more divalent linking groups is substituted or unsubstituted, and wherein the fused ring is substituted or unsubstituted. (The last sentence appears to be incomplete and possibly refers to Ar.) 1 The fused rings formed can be aliphatic or aromatic.
[0040] In equation (1), each a is independently 1 or 2.
[0041] In equation (1), b is an integer from 1 to 4. Typically, b is an integer from 1 to 2, and preferably b is 1.
[0042] In equation (1), c is an integer from 1 to 3. Typically, c is 1 or 2, preferably c is 1. For example, in some embodiments, a can be 1 or 2 and c can be 1. In some embodiments, c can be 1 and L 1 It is a single key.
[0043] In some embodiments, the anion may be free of trifluoromethyl and difluoromethylene. In other words, in some embodiments, the anion having formula (1) may be free of trifluoromethyl and difluoromethylene.
[0044] In some embodiments, Ar 1 It can be a single-ring C3-60 Aromatic group and at least one Z 1 Located in -L 1 -SO3 - The position adjacent to the indicated group. For example, Ar 1 It can be a single-ring C 3-6 Aromatic groups and at least one Z1 may be located in the group consisting of -L 1 -SO3 - The adjacent position of the indicated group. In some embodiments, Ar 1 It can be a single-ring C 3-6 Aromatic groups, L 1 It is a single bond, and at least one Z1 can be located in the region defined by -L. 1 -SO3 - The adjacent position of the indicated group.
[0045] In some embodiments, Ar 1 It can be a polycyclic C 6-60 Aromatic group, and at least one Z 1 Groups can be bonded to Ar 1 Located on the same ring by -L 1 -SO3 - The carbon atom in the ring adjacent to the group is indicated. For example, Ar 1 It can be a polycyclic C 6-60 Aromatic groups, L 1 It is a single bond, and has at least one Z. 1 Groups can be bonded to Ar 1 Located on the same ring by -L 1 -SO3 - The cyclic carbon atom located adjacent to the group indicated.
[0046] In some embodiments, in equation (1), Ar 1 It can be a polycyclic C 6-60 Aromatic group, and at least one Z 1 Groups can be bonded to Ar 1 The relative to -L 1 -SO3 - The bonded ring carbon atom is located at the β-position of the ring carbon atom, and the at least one Z 1 Groups and -L 1 -SO3 - Different rings bonded to polycyclic aromatic groups. As used herein, the term "substituent group at the β-position" refers to a substituent group bonded to the corresponding aromatic ring carbon atom on a different ring of a polycyclic system, these ring carbon atoms being separated by the bonded ring carbon atoms.
[0047] In some embodiments, the conjugate acid of the photoacid generating compound may have a pKa of 0 or less. Typically, the conjugate acid of the photoacid generating compound may have a pKa of -2 or less, preferably -5 or less. The conjugate acid of the photoacid generating compound may, for example, have a pKa of -15 to 0 or -15 to -2.
[0048] In some embodiments, an anion having formula (1) can be represented by formula (1a): (1a)
[0049] In equation (1a), Ar 1 Is it a single-ring or multi-ring C? 3-60 Aromatic groups, as defined in formula (1).
[0050] In equation (1a), each Z 1 It independently contains anionic stabilizing groups as defined in formula (1).
[0051] In equation (1a), each R 1 Independently as defined in equation (1).
[0052] In equation (1a), a is 1 or 2, and b is an integer from 0 to 4.
[0053] In some embodiments, an anion having formula (1) can be represented by one of formulas (2a) to (2f): (2a) (2b) (2c) (2d) (2e) (2f)
[0054] In equations (2a) to (2f), each Z 1 It independently contains anionic stabilizing groups as defined in formula (1).
[0055] In equations (2a) to (2f), each R 1 Independently as defined for equation (1).
[0056] In equations (2a) to (2f), a is 1 or 2, and b is an integer from 0 to 4.
[0057] In some embodiments, an anion having formula (1) can be represented by one of formulas (3a) to (3n): (3a) (3b) (3c) (3d) (3e) (3f) (3g) (3h) (3i) (3j) (3k) (3l) (3m) (3n)
[0058] In equations (3a) to (3n), each Z 1 It independently contains anionic stabilizing groups as defined in formula (1).
[0059] In equations (3a) to (3n), each R 1 Independently as defined for equation (1).
[0060] In equations (3a) to (3n), b is an integer from 0 to 4.
[0061] At least one Z1 is located in the region of -L 1 -SO3 - Exemplary groups at the adjacent positions of the indicated groups include, but are not limited to, those represented by formulas (3a), (3b), (3c), (3d), (3f), (3g), (3h), (3j), (3k), and / or (3l).
[0062] Among them, Ar 1 It is a fused polycyclic C 6-60 Aromatic group and at least one Z 1 Groups bonded to Ar 1 The relative to -L 1 -SO3 - The bonded ring carbon atom is located at the β-position of the ring carbon atom, and the at least one Z 1 Groups and -L 1 -SO3 - Bonding to fused polycyclic C 6-60 Exemplary groups of different rings of aromatic groups include, but are not limited to, those represented by formulas (3e), (3i), (3m) and / or (3n).
[0063] In other embodiments, Ar 1 It can be a fused polycyclic C 6-60 Aromatic groups, wherein at least one Z 1 Groups bonded to Ar 1 Located on the same ring by -L 1 -SO3 -The ring carbon atom adjacent to the indicated group, and at least one Z 1 Groups bonded to Ar 1 The relative to -L 1 -SO3 - The bonded ring carbon atom is located at the β-position of the ring carbon atom, and at least one Z-position is present. 1 Groups and -L 1 -SO3 - Bonding to fused polycyclic C 6-60 Different rings of aromatic groups. Structures that simultaneously satisfy the following two conditions include, but are not limited to, formulas (3f) and (3h): at least one Z1 is located in a ring formed by -L 1 -SO3 - The group is located adjacent to the group, and where Ar is located. 1 It is a multi-cyclic C 6-60 Aromatic group, and at least one of its Z groups 1 Groups bonded to Ar 1 The relative to the second substituent (containing sulfonate, -L) 1 -SO3 - The cyclic carbon atom bonded to the cyclic carbon atom is located at the β position.
[0064] In some embodiments, the nonpolymeric ionic photoacid generator compound may contain an anion represented by formula (4a): (4a)
[0065] In formula (4a), L is a single bond or a divalent linker containing 1 to 10 carbon atoms.
[0066] In equation (4a), each R 4 Independently, it is a hydroxyl, halogen, substituted or unsubstituted C. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, 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 6-30 aryloxy, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 Alkyl heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, or substituted or unsubstituted C 3-30 Heteroaryl groups. For example, each R 4 It can be halogenated, substituted or unsubstituted C independently. 1-30Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Mixed aromatic compounds.
[0067] In equation (4a), each R 4 Optionally, it may further include one or more divalent linking groups as part of its structure. Each of the one or more divalent linking groups may be substituted or unsubstituted. Exemplary divalent linking groups may be selected from -O-, -C(O)-, -C(O)O-, -S-, -S(O)-, -S(O)2-, -N(R ’ -, -C(O)N(R')-, substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 heteroaryl, or combinations thereof, wherein R ’ It can be hydrogen, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Mixed aromatic compounds.
[0068] In equation (4a), m is an integer from 0 to 4. Typically, m is an integer from 0 to 2, preferably 0 or 1.
[0069] In equation (4a), k is an integer from 1 to 5. Typically, k is an integer from 1 to 3.
[0070] In some embodiments, the nonpolymeric ionic photoacid generator compound may contain an anion represented by formula (4b): (4b)
[0071] In equation (4b), Z 1 Each of L and k is defined as in equation (4a).
[0072] Exemplary anions of the nonpolymeric ionic photoacid generating compound represented by formula (1) include the following:
[0073] The anions of non-polymeric ionic photoacid generating compounds can be obtained from commercial sources or prepared by any suitable method. For example, such anions can be prepared as described in the examples herein.
[0074] As explained above, the anionic stabilizing group is configured to form an intramolecular non-covalent bond with the sulfonate anionic group. For example, without being bound by theory, the anionic stabilizing group can form an intramolecular non-covalent bond with the sulfonate anionic group, or, for example, the anionic stabilizing group can form an intramolecular non-covalent bond with the sulfonate anionic group. In some embodiments, the intramolecular non-covalent bond can be formed in situ, such as when a non-polymeric ionic photoacid generator compound is included in a photoresist composition. In some aspects, the intramolecular non-covalent bond can be formed between the anionic stabilizing group and the sulfonate anion, such as an intramolecular hydrogen bond. The resulting intramolecular hydrogen-bonded structure can form a ring having 5-8 atoms, and most preferably 6-8 atoms. For example, an exemplary intramolecular hydrogen-bonded interaction between the anionic stabilizing group and the sulfonate anionic group is shown below in Formula (I), wherein the intramolecular hydrogen-bonded structure forms a ring having 6 atoms, but the embodiments are not limited thereto: (I)
[0075] The non-polymeric ionic photoacid generating compound further comprises an iodonium or sulfonium cation. In some embodiments, the cation may be a sulfonium cation having formula (5a) or an iodonium cation having formula (5b): (5a) (5b)
[0076] In equations (5a) and (5b), R 30 To R 34 Each is a substituted or unsubstituted C independently. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 2-30 alkenyl, substituted or unsubstituted C 2-30 Alkyne group, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 7-30 arylalkyl, or substituted or unsubstituted C 4-30 Heteroaryl alkyl groups, or combinations thereof. R 30 To R 34 Each of them can be attached to R individually or via a single bond or a divalent linker. 30 To R 34 Another group in it forms a ring. R 30 To R 34 Each of these may optionally contain a divalent linker as part of its structure. R 30 To R 34 Each of them may independently and optionally contain an acid-instable group selected from, for example, the following: tertiary alkyl ester group, secondary or tertiary aryl ester group, secondary or tertiary ester group having a combination of alkyl and aryl groups, tertiary alkoxy group, acetal group or ketal group.
[0077] An exemplary sulfonium cation having formula (5a) may include one or more of the following:
[0078] An exemplary iodonium cation having formula (5b) may include one or more of the following:
[0079] The cations used in nonpolymeric ionic photoacid generator compounds can be obtained from commercial sources or prepared using common synthetic procedures.
[0080] Suitable nonpolymeric ionic photoacid generating compounds include those generated by any combination of the aforementioned anions and cations. Nonpolymeric ionic photoacid generating compounds can be prepared by combining anionic and cationic substances under appropriate conditions.
[0081] Nonpolymeric ionic photoacid generating compounds may be included in the photoresist composition in an amount of 1 to 65 wt%, more typically 15 to 30%, 8 to 14 wt%, or 2 to 7 wt%, based on the total solids of the photoresist composition. In some embodiments, the photoresist composition may contain two or more different nonpolymeric ionic photoacid generating compounds as described herein. For example, the photoresist composition may contain one or more nonpolymeric ionic photoacid generating compounds in a combined amount of 1 to 65 wt%, more typically 15 to 30 wt%, 8 to 14 wt%, or 2 to 7 wt%, based on the total solids of the photoresist composition.
[0082] The photoresist composition may further comprise additional photoacid generators. The additional PAG may be in ionic or nonionic form. The additional PAG may be in polymeric or nonpolymeric form. When in polymeric form, the additional PAG may be present as part of a repeating unit in a polymer derived from a polymerizable PAG monomer.
[0083] In some embodiments, the additional photoacid generator may produce photoacid with a higher acidity than that produced by the aforementioned non-polymeric ionic photoacid generator compound. In other embodiments, the additional photoacid generator does not produce photoacid with a higher acidity than that produced by the aforementioned non-polymeric ionic photoacid generator compound.
[0084] Suitable alternative PAG compounds may have the formula G + A - G + It is a photoactive cation and A -The photoactive cation is an anion capable of generating photoacids. The photoactive cation is preferably selected from ononium cations, preferably iodonium or sulfonium cations, such as those described above with respect to the non-polymeric ionic photoacid generating compounds of the present invention (e.g., those having formulas (5a) and / or (5b)). Particularly suitable anions include those whose conjugate acid has a pKa of -18 to 0, or -15 to 0, or -14 to 0, or -13 to 0. The anion is typically an organic anion having a sulfonate group or a non-sulfonate group such as sulfonamidate, sulfonimidate, methyl, arsenate, or borate. In some embodiments, the additional PAG may have an anion having the structure of formula (1) as defined for the anion of the non-polymeric ionic photoacid generating compound, wherein the anion of the additional PAG compound does not include the group Z as an anion stabilizing group. 1 .
[0085] In some respects, the anions of additional PAGs do not include and are free from -F, -CF3, or -CF2- groups. It should be understood that "free from -F, -CF3, or -CF2- groups" means that the anions of additional PAGs do not include groups such as -CH2CF3 and -CH2CF2CH3. In other respects, the anions of additional PAGs are fluorine-free (i.e., they do not contain fluorine atoms and are not substituted by fluorine-containing groups). In some respects, additional PAGs are fluorine-free (i.e., neither the photoactive cation nor the anion is fluorine-free).
[0086] Exemplary onium salts may include, for example, triphenylsulfonium trifluoromethane sulfonate, (p-tert-butoxyphenyl)diphenylsulfonium trifluoromethane sulfonate, tri(p-tert-butoxyphenyl)sulfonium trifluoromethane sulfonate, triphenylsulfonium p-toluene sulfonate; di-tert-butylphenyl iodomonium perfluorobutane sulfonate, and di-tert-butylphenyl iodomonium camphor sulfonate. Other available PAG compounds are known in the field of chemically enhanced photoresists and include, for example: nonionic sulfonyl compounds, such as 2-nitrobenzyl p-toluenesulfonate, 2,6-dinitrobenzyl p-toluenesulfonate, and 2,4-dinitrobenzyl p-toluenesulfonate; sulfonates, such as 1,2,3-tris(methanesulfonyloxy)benzene, 1,2,3-tris(trifluoromethanesulfonyloxy)benzene, and 1,2,3-tris(p-toluenesulfonyloxy)benzene; and diazomethane derivatives, such as bis(benzenesulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, and bis(p-toluenesulfonyl)diazomethane. Nitrogen-based methanes; dioxime derivatives, such as bis-O-(p-toluenesulfonyl)-α-dimethyldioxime and bis-O-(n-butanesulfonyl)-α-dimethyldioxime; 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 additional PAGs are further described in U.S. Patent Nos. 8,431,325 and 4,189,323.
[0087] Typically, when the photoresist composition contains additional non-polymeric PAG, the additional PAG is present in the photoresist composition in an amount of 0.1 to 55 wt%, more typically 1 to 25 wt%, based on the total solids of the photoresist composition. When present in polymeric form, the additional PAG is typically included in the polymer in an amount of 1 to 25 mol%, more typically 1 to 8 mol%, or 2 to 6 mol%, based on the total repeating units in the polymer.
[0088] The photoresist composition further comprises one or more non-solvent-based, alkali-insoluble base materials present in an amount greater than 50% by weight of the total solids of the photoresist composition. These one or more non-solvent-based, alkali-insoluble base materials (which may alternatively be referred to herein as matrix materials) may be polymeric or non-polymeric. Suitable alkali-insoluble base materials will be apparent to those skilled in the art and based on the specification provided herein. In some embodiments, the alkali-insoluble base material does not contain phenolic hydroxyl groups, such as phenolic varnish resins containing phenolic hydroxyl groups. In some embodiments, the alkali-insoluble base material does not contain carboxylic acid groups. In some embodiments, the alkali-insoluble base material may contain phenolic hydroxyl groups and / or carboxylic acid groups, provided that the alkali insolubility of the base material is maintained.
[0089] To determine whether a particular base material is alkali-insoluble, the base material can be subjected to a solubility test using an aqueous solution of an alkaline developer, such as a 0.26 N tetramethylammonium hydroxide (TMAH) aqueous solution. Alkali solubility can be determined, for example, by spin-coating a film of the base material onto the surface of a Si substrate and measuring the initial film thickness. Alternatively, the film of the base material can be immersed in a 0.26 N TMAH aqueous solution at room temperature for 60 seconds, followed by DI water rinsing and air drying, typical development conditions, and then the film thickness can be measured again. Alkali insolubility is indicated by a thickness variation of less than 2 nanometers (nm), preferably less than 1 nm, less than 0.5 nm, less than 0.1 nm, or 0 nm.
[0090] In some embodiments, the base material may include polymers, metallic materials, or combinations thereof. It should be understood that “base material” does not define the material as alkaline (e.g., according to the definition of acid / base chemistry, the base material is not necessarily alkaline).
[0091] The polymer of the photoresist composition can be a homopolymer or a copolymer containing two or more repeating units with different structures. For example, the polymer can contain one or more repeating units containing functional groups selected from the following: hydroxyaryl, acid-labile, alkali-soluble, lactone-containing, sulfonyl-containing, polar, crosslinkable, crosslinking, etc., or combinations thereof.
[0092] In one or more embodiments, the polymer may comprise repeating units formed from monomers including acid-labile groups. Suitable acid-labile groups include, for example, tertiary ester groups, acetal groups, ketal groups, and tertiary ether groups. Where R dIt is hydrogen, halogen (e.g., F, Cl, Br, I), substituted or unsubstituted C 1-6 Alkyl, or substituted or unsubstituted C 3-6 Cycloalkyl.
[0093] When repeating units with acid-labile groups are present in a polymer, they are typically present in amounts of 25 to 75 mol%, more typically 25 to 50 mol%, and even more typically 30 to 50 mol%, based on the total repeating units in the polymer.
[0094] In some embodiments, the polymer may comprise repeating units derived from one or more lactone-containing monomers. Suitable lactone-containing monomers include, for example: Where R d It is hydrogen, halogen (e.g., F, Cl, Br, I), substituted or unsubstituted C 1-6 Alkyl, or substituted or unsubstituted C 3-6 Cycloalkyl.
[0095] When repeating units derived from one or more lactone-containing monomers are present in a polymer, they are typically present in amounts of 0.5 to 75 mol%, more typically 1 to 50 mol%, and even more typically 5 to 50 mol%, based on the total repeating units in the polymer.
[0096] In some embodiments, the polymer may comprise repeating units having alkali-soluble groups and / or having a pKa of less than or equal to 12. Exemplary alkali-soluble groups may include fluorohydrin groups, carboxylic acid groups, carboximide groups, sulfonamide groups, or sulfonimide groups.
[0097] Non-limiting examples of monomers containing alkali-soluble groups include the following: Where R i It is hydrogen, halogen (e.g., F, Cl, Br, I), substituted or unsubstituted C 1-6 Alkyl, or substituted or unsubstituted C 3-6Cycloalkyl.
[0098] When repeating units having alkali-soluble groups and / or having a pKa of less than or equal to 12 are present in a polymer, they are typically present in amounts of 0.5 to 30 mol%, more typically 15 to 25 mol%, and even more typically 5 to 10 mol%, based on the total repeating units in the polymer.
[0099] The polymer may further optionally comprise one or more repeating units containing aromatic groups. For example, such repeating units may include one or more of the following: Where R b It is hydrogen, halogen (e.g., F, Cl, Br, I), substituted or unsubstituted C 1-6 Alkyl, or substituted or unsubstituted C 3-6 Cycloalkyl.
[0100] When present, the polymer typically contains repeating units containing aromatic groups in amounts of 1 to 80 mol%, more typically 5 to 75 mol%, and even more typically 5 to 50 mol%, based on the total repeating units in the polymer.
[0101] In some embodiments, the polymer may optionally comprise repeating units derived from acetal monomers that do not include ester acetals, such as monomers having formula (5): (5)
[0102] In equation (5), X b It is a polymerizable group, which can be a carbon-carbon unsaturated vinyl group; L 2 It is selected from substituted or unsubstituted C 1-10 Alkylene, substituted or unsubstituted C 3-10 Cycloalkylene, substituted or unsubstituted C 3-10 Heterocyclic alkyl, substituted or unsubstituted C 6-12 aryl, substituted or unsubstituted C 4-12 A divalent linker group of heteroaryl or a combination thereof.
[0103] In equation (5), R 7 and R 8 Each is independently a hydrogen, substituted or unsubstituted C. 1-20 Alkyl, substituted or unsubstituted C 3-20 cycloalkyl, substituted or unsubstituted C 3-20 Heterocyclic alkyl, substituted or unsubstituted C 6-20 aryl, substituted or unsubstituted C 7-30 arylalkyl, substituted or unsubstituted C 7-30alkylaryl, substituted or unsubstituted C 3-20 heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, or substituted or unsubstituted C 4-30 Alkyl heteroaryl. Preferably, R 7 and R 8 Each is independently a hydrogen, substituted or unsubstituted C. 1-20 Alkyl, substituted or unsubstituted C 3-20 cycloalkyl, or substituted or unsubstituted C 3-20 Heterocyclic alkyl. R 7 and R 8 Each of them may optionally further include a divalent linker as part of its structure.
[0104] In equation (5), R 9 Is it substituted or unsubstituted C? 1-20 Alkyl, substituted or unsubstituted C 3-20 cycloalkyl, or substituted or unsubstituted C 3-20 Heterocyclic alkyl. R 9 Optionally, it may further include a divalent linker group as part of its structure.
[0105] In equation (5), R 7 Or R 8 One of them can optionally be with R 9 Together, they form a heterocycle via single bonds or divalent linkages, wherein the ring is substituted or unsubstituted. The ring can be monocyclic, non-fused polycyclic, or fused polycyclic, and is typically monocyclic when formed.
[0106] Non-limiting examples of monomers represented by equation (5) include: Where R d It is a hydrogen, fluorine, cyano, substituted or unsubstituted C group. 1-10 alkyl.
[0107] When present, the polymer typically contains repeating units having acetal monomers excluding ester acetals in amounts of 1 to 80 mol%, more typically 5 to 75 mol%, and even more typically 5 to 50 mol%, based on the total repeating units in the polymer.
[0108] The polymer may further optionally comprise one or more additional repeating units. These additional repeating units may be, for example, units used to modulate the properties of the photoresist composition, such as etching rate and solubility. Exemplary additional units may include those derived from one or more of (meth)acrylates, vinyl aromatic compounds, vinyl ethers, vinyl ketones, and / or vinyl ester monomers. These one or more additional repeating units (if present in the polymer) may be used in amounts up to 50 mol%, typically 3 to 50 mol%, based on the total repeating units of the polymer.
[0109] Non-limiting exemplary polymers of the present invention include one or more of the following: Where a, b, and c represent the mole fractions of the repeating units of the polymer, and a + b + c = 1. It should be understood that the mole fractions of a, b, and c are chosen such that the polymer is alkali-insoluble.
[0110] In some embodiments, the non-solvent alkali-insoluble base material may include a chain-scissionable polymer, a chain-degrading polymer, or a combination thereof.
[0111] Chain-severable polymers can undergo chain-cleaving reactions under suitable conditions. Any suitable chain-severable polymer can be used. Exemplary direct photolysis-based chain-severable polymers include, for example, copolymers of one or more α-substituted styrene and substituted α-halogen acrylates, such as α-methylstyrene / methyl-α-chloroacrylate copolymers, 2-trifluoroethyl-α-chloroacrylate / α-methyl-4-fluorostyrene copolymers, and combinations thereof.
[0112] De-chaining polymers include polymers with de-chaining polymeric end groups that, upon a suitable stimulus (photo-induced or chemically induced), trigger the breaking of the polymer backbone into smaller segments. Typically, de-chaining polymers are chosen such that a first chemical modification or degradation event triggers some or all of the de-chaining effect. Any suitable de-chaining polymer can be used.
[0113] The polymer typically has a weight-average molecular weight (Mn) of 1,000 to 200,000 Daltons (Da), preferably 10,000 to 150,000 Da, more preferably 15,000 to 150,000 Da, and even more preferably 25,000 to 150,000 Da or 50,000 to 150,000 Da. w The first polymer's polydispersity index (PDI) (which is M) w Number-average molecular weight (M n The ratio of 1.1 to 3 is typically 1.1 to 3, and more typically 1.1 to 2. Molecular weight values are determined by gel permeation chromatography (GPC) using polystyrene standards.
[0114] Polymers can be prepared using any suitable method or one method in the art. For example, one or more monomers corresponding to the repeating units described herein can be fed together or separately using suitable solvents or initiators and polymerized in a reactor. For example, polymers can be obtained by polymerizing the respective monomers under any suitable conditions, such as by heating at an effective temperature, irradiation with photochemical radiation at an effective wavelength, or a combination thereof.
[0115] In some embodiments, one or more non-solvent-based base materials insoluble in alkali may be metal-containing materials. Exemplary metal-containing materials include organometallic resists (e.g., photo-induced crosslinkable organometallic resists), metal oxide resists, and combinations thereof. In some embodiments, metal-containing materials may include Sn, Zr, Hf, Si, Ge, Se, Cr, Mo, W, V, Nb, Ta, P, Sb, Ti, Ce, Ru, Sb, Y, Ga, Cr, Fe, Co, Ru, Al, In, Sc, Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Zn, Co, Ni, Mn, Mg, Ca, Sr, Ba, and combinations thereof. Typically, metal-containing materials may include Sn, Zr, Hf, Si, Ge, Se, and combinations thereof.
[0116] One or more non-solvent-based base materials are present in an amount greater than 50 wt% of the total solids of the photoresist composition. For example, one or more non-solvent-based base materials may be present in an amount of 50 wt% to 99 wt%, typically 60 wt% to 95 wt%, or 70 wt% to 90 wt% of the total solids of the photoresist composition.
[0117] The photoresist composition further comprises a solvent for dissolving the components of the composition and promoting its coating on a substrate. Preferably, the solvent is an organic solvent commonly used in the manufacture of electronic devices. Suitable solvents include, for example: aliphatic hydrocarbons such as hexane and 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) (DAA); 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... Cyclohexanone (CHO); esters, such as ethyl acetate, n-butyl acetate, propylene glycol monomethyl ether acetate (PGMEA), ethyl lactate (EL), methyl hydroxyisobutyrate (HBM), and ethyl acetoacetate; lactones, such as γ-butyrolactone (GBL) and ε-caprolactone; lactams, such as N-methylpyrrolidone; nitriles, such as acetonitrile and propionitrile; cyclic or acyclic 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; or combinations thereof. Among these, preferred solvents are PGME, PGMEA, EL, GBL, HBM, CHO, DAA, or combinations thereof.
[0118] The total solvent content (i.e., the cumulative solvent content of all solvents) in the photoresist composition is typically 40 to 99 wt%, for example 60 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 photoresist layer being coated and the coating conditions.
[0119] In some aspects, the photoresist composition may further comprise a material containing one or more base-indestructible groups (“base-indestructible material”). As mentioned herein, a base-indestructible group is a functional group that can undergo a cleavage reaction in the presence of an aqueous base developer after the exposure and post-exposure baking steps to provide a polar group (such as hydroxyl, carboxylic acid, sulfonic acid, etc.). The base-indestructible group will not react significantly prior to the development step of the photoresist composition containing the base-indestructible group (e.g., will not undergo a bond-breaking reaction). Therefore, for example, the base-indestructible group will be substantially inert during the pre-exposure soft bake step, the exposure step, and the post-exposure baking step. “Substantially inert” means during the pre-exposure soft bake step, the exposure step, and the post-exposure baking step. 5%, typically 1% of the base-unstable group (or portion) will decompose, cleave, or react. The base-unstable group is reactive under typical photoresist development conditions using, for example, aqueous base photoresist developers (such as an aqueous solution of tetramethylammonium hydroxide (TMAH) at a concentration of 0.26 N). For example, a 0.26 N aqueous solution of TMAH can be used for single-immersion or dynamic development, where, for example, 0.26 N TMAH developer is dispensed onto the imaged photoresist layer for a suitable duration (e.g., 10 to 120 seconds). Exemplary base-unstable groups are ester groups, typically fluorinated ester groups. Preferably, the base-unstable material is substantially immiscible with the first and / or second polymers and other solid components of the photoresist composition and has a lower surface energy than them. Thus, when coated onto a substrate, the base-unstable material can separate from the other solid components of the photoresist composition to reach the top surface of the formed photoresist layer.
[0120] In some respects, an alkali-insecure material can be a polymeric material that may contain one or more repeating units having one or more alkali-insecure groups (also referred to herein as an alkali-insecure polymer). For example, an alkali-insecure polymer may contain repeating units having two or more identical or different alkali-insecure groups. Preferred alkali-insecure polymers contain at least one repeating unit having two or more alkali-insecure groups, such as repeating units having two or three alkali-insecure groups.
[0121] Base-instable polymers can be prepared using any suitable method in the art, including those described herein with respect to the first and second polymers. For example, base-instable polymers can be obtained by polymerization of the corresponding monomers under any suitable conditions, such as by heating at an effective temperature, irradiation with photochemical radiation at an effective wavelength, or a combination thereof. Furthermore or alternatively, suitable methods can be used to graft one or more base-instable groups onto the polymer backbone.
[0122] In some respects, alkali-instable materials are single molecules comprising one or more alkali-instable ester groups, preferably one or more fluorinated ester groups. Alkali-instable materials that are single molecules typically have an M value in the range of 50 to 1,500 Da. w .
[0123] When present, alkali-instable materials are typically present in the photoresist composition in an amount of 0.01 to 10 wt% or 2 to 7 wt%, typically 1 to 5 wt%, based on the total solids of the photoresist composition.
[0124] In addition or alternatively, besides alkali-insoluble polymers, the photoresist composition may further comprise one or more polymers that are different from and not equivalent to the non-solvent-based alkali-insoluble base materials described above. For example, the photoresist composition may comprise other polymers as described above but with different compositions. In addition or alternatively, the one or more additional polymers may include those well known in the field of photoresists, such as those selected from: polyacrylates, polyvinyl ethers, polyesters, polynorbornene, polyacetals, polyethylene glycol, polyamides, polyacrylamide, polyphenols, phenolic varnishes, styrene polymers, polyvinyl alcohol, or combinations thereof.
[0125] The photoresist composition may further comprise one or more additional optional additives. For example, optional additives may include photochemical dyes and contrast dyes, anti-stripping agents, plasticizers, accelerators, sensitizers, photodegradable quenchers (PDQ) (and also referred to as photodegradable bases), alkaline quenchers, hot acid generators, 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.
[0126] PDQ produces a weak acid upon irradiation. The acid produced by the photodegradable quencher is not strong enough to react rapidly with acid-indegradable groups present in the resist matrix. Exemplary photodegradable quenchers include, for example, anions of weak acids (pKa > 1) such as Cp. 1-20 Carboxylic acid or C 1-20 The photodegradable quencher is a photodegradable cation paired with the anion of a sulfonic acid, and preferably those that can also be used to prepare strong acid generating compounds. Exemplary carboxylic acids include formic acid, acetic acid, propionic acid, tartaric acid, succinic acid, cyclohexanecarboxylic acid, benzoic acid, salicylic acid, etc. Exemplary sulfonic acids include p-toluenesulfonic acid, camphorsulfonic acid, etc. In a preferred embodiment, the photodegradable quencher is a photodegradable organic zwitterionic compound, such as diphenyliodonium-2-carboxylate.
[0127] The photodegradable quencher can be in non-polymeric or polymerically bonded form. When in polymeric form, the photodegradable quencher is present in polymeric units on a first or second polymer. The polymeric units containing the photodegradable quencher are typically present in an amount of 0.1 to 30 mol%, preferably 1 to 10 mol%, and more preferably 1 to 2 mol%, based on the total repeating units in the polymer.
[0128] Exemplary basic quenchers include, for example, straight-chain aliphatic amines such as tributylamine, trioctylamine, triisopropanolamine, tetra(2-hydroxypropyl)ethylenediamine, N-tert-butyldiethanolamine, tris(2-acetoxy-ethyl)amine, 2,2',2'',2'''-(ethane-1,2-diylbis(azanetriyl))tetraethanol, 2-(dibutylamino)ethanol, and 2,2',2''-nitrotriethanol; cyclic aliphatic amines, such as 1-(tert-butoxycarbonyl)-4-hydroxypiperidine, tert-butyl 1-pyrrolidinecarboxylate, tert-butyl 2-ethyl-1H-imidazolium-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)propyl-2-ylcarbamate; ammonium salts, such as quaternary ammonium salts of sulfonates, aminosulfonates, carboxylates, and phosphonates; imines, such as primary and secondary aldehyde imines 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.
[0129] The alkaline quencher can be in non-polymeric or polymeric form. When in polymeric form, the quencher can be present in repeating units of the polymer. The repeating units containing the quencher are typically present in an amount of 0.1 to 30 mol%, preferably 1 to 10 mol%, and more preferably 1 to 2 mol%, based on the total repeating units in the polymer.
[0130] Exemplary surfactants include fluorinated and nonfluorinated surfactants and may be ionic or nonionic, with nonionic surfactants being preferred. Exemplary fluorinated nonionic surfactants include perfluorinated C4 surfactants, such as FC-4430 and FC-4432 surfactants available from 3M Corporation; and fluorinated glycols, such as POLYFOX PF-636, PF-6320, PF-656, and PF-6520 fluorinated surfactants from Omnova. In one aspect, the photoresist composition further comprises a surfactant polymer containing fluorinated repeating units.
[0131] A patterning method using the photoresist composition of the present invention will now be described. Suitable substrates on which the photoresist composition can be coated 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.; wherein semiconductor wafers are typical. Such substrates are typically composed of one or more of silicon, polycrystalline silicon, silicon oxide, silicon nitride, silicon oxynitride, silicon germanide, 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 for manufacturing integrated circuits, optical sensors, flat panel displays, integrated optical circuits, and LEDs. Such substrates can have any suitable size. Typical wafer substrate diameters are 200 to 300 millimeters (mm), although wafers with smaller and larger diameters can be suitably used according to the present invention. The substrate may include one or more layers or structures, which may optionally include active or operable portions of the formed device.
[0132] Typically, prior to coating the photoresist composition of the present invention, one or more photolithographic layers, such as hard mask layers (e.g., spin-coated carbon (SOC), amorphous carbon, or metal hard mask layers), CVD layers (e.g., silicon nitride (SiN), silicon oxide (SiO), or silicon oxynitride (SiON) layers), organic or inorganic underlayers, or combinations thereof, are provided on the upper surface of the substrate. These layers, together with the externally coated photoresist layer, form a photolithographic material stack.
[0133] Optionally, a layer of adhesion promoter can be applied to the substrate surface prior to coating the photoresist composition. If an adhesion promoter is desired, any suitable adhesion promoter for polymer films can be used, such as silanes, typically organosilanes like trimethoxyvinylsilane, triethoxyvinylsilane, hexamethyldisilazane, or aminosilane coupling agents like γ-aminopropyltriethoxysilane. Particularly suitable adhesion promoters include those sold from DuPont Electronics & Industrial (Marlborough, Massachusetts) under the names AP™ 3000, AP™ 8000, and AP™ 9000S.
[0134] Photoresist compositions can be coated onto a substrate by any suitable method, including spin coating, spray coating, dip coating, blade coating, etc. For example, the application of a photoresist layer can be accomplished by spin coating the photoresist in a solvent using a coating track, wherein the photoresist is dispensed onto a rotating wafer. During dispensing, the wafer is typically rotated at a speed of up to 4,000 rpm, for example 200 to 3,000 rpm, or 1,000 to 2,500 rpm, for a period of 15 to 120 seconds to obtain a layer of photoresist composition on the substrate. Those skilled in the art will understand that the thickness of the coated layer can be adjusted by changing the rotation speed and / or the total solids of the composition. The photoresist composition layer formed from the compositions of the present invention typically has a dry layer thickness of 1 nanometer (nm) to 120 micrometer (μm), preferably greater than 5 nm to 110 μm, and more preferably 6 to 100 μm. In some embodiments, the photoresist composition layer formed from the composition may have a dry layer thickness of 10 nm to 5 μm or 3 to 20 μm.
[0135] Next, the photoresist composition is typically soft-baked to minimize the solvent content in the layer, thereby forming a non-stick coating and improving the adhesion of the layer to the substrate. Soft baking is performed, for example, on a heated plate or in an oven, with a heated plate being typical. The soft baking temperature and time will depend, for example, on the photoresist composition and thickness. Soft baking temperatures are typically 80°C to 170°C, and more typically 90°C to 150°C. Soft baking times are typically 10 seconds to 20 minutes, more typically 1 to 10 minutes, and even more typically 1 to 2 minutes. Those skilled in the art can readily determine the heating time based on the composition.
[0136] Next, the photoresist layer is patterned and exposed to activating radiation to create a solubility difference between the exposed and unexposed areas. The exposure of the photoresist composition to radiation that activates the composition, as described herein, indicates that radiation can form a latent image in the photoresist composition. Exposure is typically performed using a patterned photomask with optically transparent and optically opaque regions corresponding to the areas of the photoresist layer to be exposed and the areas of the unexposed photoresist layer, respectively. Alternatively, such exposure can be performed without a photomask using a direct-write method, typically used in electron beam lithography. The activating radiation typically has wavelengths less than 400 nm, less than 300 nm, or less than 200 nm, with wavelengths of 248 nm (KrF), 193 nm (ArF), 13.5 nm (EUV), or electron beam lithography being preferred. Preferably, the activating radiation is 248 nm radiation. These methods can be used in immersion or dry (non-immersion) lithography techniques. Exposure energy is typically 1 to 200 millijoules per square centimeter (mJ / cm²). 2 ), preferably 10 to 100 mJ / cm 2 And more preferably 20 to 50 mJ / cm 2 This depends on the composition of the exposure tool and the photoresist composition.
[0137] After the photoresist layer is exposed, post-exposure baking (PEB) of the exposed photoresist layer is performed. PEB can be performed, for example, on a heated plate or in an oven, with a heated plate being typical. The conditions of PEB will depend, for example, on the photoresist composition and the layer thickness. PEB is typically performed at temperatures of 70°C to 150°C, preferably 75°C to 120°C, for a time of 30 to 120 seconds. A latent image, defined by polarity-converted regions (exposed regions) and polarity-unconverted regions (unexposed regions), is formed in the photoresist.
[0138] The exposed photoresist layer is then developed with a suitable developer to selectively remove areas of the layer that are soluble in the developer, while the remaining insoluble areas form the resulting photoresist pattern relief image. In the case of a positive development (PTD) process, the exposed areas of the photoresist layer are removed during development, while the unexposed areas are retained. Conversely, in a negative development (NTD) process, the exposed areas of the photoresist layer are retained during development, while the unexposed areas are removed. The developer can be applied by any suitable method, as described above regarding the application of the photoresist composition, with spin coating being typical. The development time is the period of time during which the soluble areas of the photoresist are effectively removed, typically 5 to 60 seconds. Development is typically performed at room temperature.
[0139] Suitable developers for PTD processes include aqueous alkaline developers, such as quaternary ammonium hydroxide solutions, such as tetramethylammonium hydroxide (TMAH) (preferably 0.26 equivalent (N) TMAH), tetraethylammonium hydroxide, tetrabutylammonium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, etc. Suitable developers for NTD processes 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, 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. Typical developers are 2-heptanone or n-butyl acetate.
[0140] The 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 layer of photoresist composition on the one or more layers to be patterned.
[0141] Photoresist patterns can be used, for example, as an etch mask to transfer the pattern to one or more sequentially arranged underlying layers using known etch techniques, typically dry etching (such as reactive ion etching). Photoresist patterns can also be used, for example, to transfer a pattern to an underlying hard mask layer, which in turn serves as an etch mask for transferring the pattern to one or more layers below the hard mask layer. If the photoresist pattern is not lost during pattern transfer, it can be removed from the substrate using known techniques such as oxygen plasma ashing. When used in one or more such patterning processes, photoresist compositions can be used to manufacture semiconductor devices such as memory devices, processor chips (CPUs), graphics chips, optoelectronic chips, LEDs, OLEDs, and other electronic devices.
[0142] The invention is further illustrated by the following non-limiting examples. Examples
[0143] All reactions were carried out under ambient atmospheric conditions. All chemicals used were sourced directly from the supplier. Unless otherwise specified, NMR spectra for all compounds were obtained on a 500 MHz spectrometer. Chemical shifts are reported as δ (parts per million, ppm) values relative to the signal from the internal deuterated chloroform residue. Multiplicity is indicated by s (singleton), d (doublet), t (triplet), m (multiplex), dd (doublet), dt (doubletuplet), tt (tripletuplet), and br (broad singlet).
[0144] The following photoacid generators were prepared in the synthesis examples for use in the following photolithography examples. Synthetic Example: Synthesis of Tetraethylammonium 2-hydroxy-4-((4-iodophenoxy)carbonyl)benzenesulfonate
[0145] N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (5.75 g, 30 mmol) was added to a mixture of potassium 4-carboxy-2-hydroxybenzenesulfonate (6.41 g, 25 mmol), 4-iodophenol (8.25 g, 37.5 mmol), tetraethylammonium chloride (8.29 g, 50 mmol), and 4-pyrrolidinylpyridine (185 mg, 1.25 mmol) in N,N-dimethylformamide (DMF, 75 mL) at room temperature. The reaction was stirred for 3 hours (hr). The reaction was then quenched by pouring into an aqueous solution of tetraethylammonium chloride (20% w / v, 500 mL). The resulting mixture was extracted with dichloromethane (DCM, 4 × 100 mL), and the combined organic layers were washed with an aqueous solution of tetraethylammonium chloride (20% w / v, 3 × 50 mL) and water (3 × 100 mL). The organic layer was dried over filter paper and concentrated under vacuum. The resulting residue was resuspended in acetone (50 mL) and added dropwise to a stirred solution of methyl tert-butyl ether (500 mL). The oily precipitate was separated by decanting the mother liquor and washing with excess methyl tert-butyl ether. The residual solvent was removed by storing in a vacuum oven at 3°C overnight to give a product (6.08 g, 44%) as a colorless oil. 1 ¹H NMR (499 MHz, DMSO-d⁶) δ 10.71 (s, 1H), 7.81 (d, J = 8.9 Hz, 2H), 7.66 (d, J = 8.0 Hz, 1H), 7.56 (dd, J = 8.0, 1.7 Hz, 1H), 7.47 (d, J = 1.6 Hz, 1H), 7.15 (d, J = 8.7 Hz, 2H), 3.19 (q, J = 7.3 Hz, 8H), 1.15 (tt, J = 7.3, 1.7 Hz, 12H). Synthesis of phenyl(3-(trifluoromethyl)phenyl)iodonium 2-hydroxy-4-((4-iodophenoxy)carbonyl)benzenesulfonate (D1):
[0146] Tetraethylammonium 2-hydroxy-4-((4-iodophenoxy)carbonyl)benzenesulfonate (2.0 g, 3.63 mmol) and phenyl(3-(trifluoromethyl)phenyl)iodonium chloride (1.40 g, 3.63 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (50 mL) and water (50 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was doped with n-heptane to achieve a final ratio of n-heptane:DCM of 1:3. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and then added to a stirred solution of n-heptane (500 mL) to form a precipitate. The precipitate was separated by decantation of the mother liquor and washed with excess n-heptane. The residual solvent was removed by storing the product in a vacuum oven at 35°C overnight to obtain product D1 (1.76 g, 63%) as an amorphous colorless solid. 1 H NMR (499 MHz, DMSO-d6) δ 10.71 (s, 1H), 8.75 (s, 1H), 8.55 (d, J = 8.1Hz, 1H), 8.31 (d, J = 7.7 Hz, 2H), 8.02 (d, J = 7.9 Hz, 1H), 7.80 (d, J = 8.7Hz, 2H), 7.75 (t, J = 8.0 Hz, 1H), 7.67 (t, J = 7.9 Hz, 2H), 7.59 - 7.51 (m,3H), 7.49 (d, J = 1.7 Hz, 1H), 7.17 - 7.12 (m, 2H). 19 F NMR (470 MHz, DMSO) δ -61.22. Synthesis of tris(4-fluorophenyl)sulfonium 2-hydroxy-4-((4-iodophenoxy)carbonyl)benzenesulfonate (D2):
[0147] Tetraethylammonium 2-hydroxy-4-((4-iodophenoxy)carbonyl)benzenesulfonate (2.0 g, 3.63 mmol) and tris(4-fluorophenyl)sulfonium bromide (1.45 g, 3.63 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (50 mL) and water (50 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was doped with n-heptane to achieve a final ratio of n-heptane:DCM of 1:3. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and added to a stirred solution of n-heptane (500 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. Residual solvent was removed by storage in a vacuum oven at 35°C overnight to give product D2 (1.53 g, 57%) as a white solid. 1 H NMR (499 MHz, DMSO-d6) δ10.70 (s, 1H), 7.97 - 7.89 (m, 6H), 7.81 (dt, J = 8.7, 2.0 Hz, 2H), 7.66 (t,J = 8.1 Hz, 7H), 7.55 (dd, J = 8.0, 1.7 Hz, 1H), 7.46 (d, J = 1.7 Hz, 1H), 7.18 - 7.12 (m, 2H). 19 F NMR (470 MHz, DMSO) δ -103.50. Synthesis of tetraethylammonium 4-((2-fluorophenoxy)carbonyl)-2-hydroxybenzenesulfonic acid:
[0148] N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (3.59 g, 18.2 mmol) was added to a mixture of potassium 4-carboxy-2-hydroxybenzenesulfonate (4.00 g, 15.6 mmol), 2-fluorophenol (2.62 g, 23.4 mmol), tetraethylammonium chloride (5.17 g, 31.2 mmol), and 4-pyrrolidinylpyridine (100 mg) in DMF (30 mL) at room temperature. The mixture was stirred overnight at room temperature. The reaction was quenched by pouring into an aqueous solution of tetraethylammonium chloride (20% w / v, 500 mL). The resulting mixture was extracted with DCM (4 × 100 mL), and the combined organic layers were washed with an aqueous solution of tetraethylammonium chloride (20% w / v, 3 × 50 mL) and water (3 × 100 mL). The organic layers were dried over filter paper and concentrated under reduced pressure. The resulting residue was resuspended in acetone (50 mL) and added dropwise to a stirred solution of methyl tert-butyl ether (500 mL) to form a precipitate. The oily precipitate was separated by decantation of the mother liquor and washing with excess methyl tert-butyl ether. The residual solvent was removed by storing the product overnight in a vacuum oven at 35°C to give a colorless oily product (3.20 g, 46%). 1 ¹H NMR (499 MHz, DMSO-d⁶) δ 7.71 (d, J = 8.0 Hz, 1H), 7.61 (dd, J = 8.1, 1.7 Hz, 1H), 7.51 (d, J = 1.7 Hz, 1H), 7.50 - 7.36 (m, 3H), 7.31 (td, J = 7.6, 1.7 Hz, 1H), 3.20 (q, J = 7.3 Hz, 8H), 1.27 - 1.12 (t, 12H). Synthesis of bis(4-(tert-butyl)phenyl)iodonium 4-((2-fluorophenoxy)carbonyl)-2-hydroxybenzenesulfonate (D₃):
[0149] Tetraethylammonium 4-((2-fluorophenoxy)carbonyl)-2-hydroxybenzenesulfonate (3.20 g, 7.2 mmol) and bis(4-(tert-butyl)phenyl)iodonium acetate (2.95 g, 6.5 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (70 mL) and water (70 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and added to a stirred solution of methyl tert-butyl ether (500 mL) to provide a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. Residual solvent was removed by storage in a vacuum oven at 35°C overnight to give product D3 (2.60 g, 50%) as a white solid. 1 H NMR (499 MHz, DMSO-d6) δ 10.80 (s, 1H), 8.20 - 8.14 (m, 4H), 7.71 (d, J = 8.0 Hz, 1H), 7.59 (dd, J = 8.0, 1.7 Hz, 1H), 7.56 -7.49 (m, 5H), 7.48- 7.33 (m, 3H), 7.29 (td, J = 7.7, 1.8 Hz, 1H), 1.26 (s, 18H). 19 F NMR (470MHz, DMSO) δ 129.50. Synthesis of tetraethylammonium 4-((2,6-difluorophenoxy)carbonyl)-2-hydroxybenzenesulfonic acid:
[0150] N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (3.59 g, 18.2 mmol) was added to a mixture of potassium 4-carboxy-2-hydroxybenzenesulfonate (4.00 g, 15.6 mmol), 2,6-difluorophenol (3.04 g, 23.4 mmol), tetraethylammonium chloride (5.17 g, 31.2 mmol), and 4-pyrrolidinylpyridine (100 mg) in DMF (30 mL) at room temperature. The mixture was stirred overnight at room temperature. The reaction was quenched by pouring into an aqueous solution of tetraethylammonium chloride (20% w / v, 500 mL). The resulting mixture was extracted with DCM (4 × 100 mL), and the combined organic layers were washed with an aqueous solution of tetraethylammonium chloride (20% w / v, 3 × 50 mL) and water (3 × 100 mL). The organic layers were dried over filter paper and concentrated under reduced pressure. The resulting residue was resuspended in acetone (50 mL) and added dropwise to a stirred solution of methyl tert-butyl ether (500 mL) to form a precipitate. The oily precipitate was separated by decantation of the mother liquor and washing with excess methyl tert-butyl ether. The residual solvent was removed by storing the product overnight in a vacuum oven at 35°C to give a colorless oily product (4.20 g, 59%). 1 ¹H NMR (499MHz, acetone-d6) δ 7.84 (d, J = 8.1 Hz, 1H), 7.66 (dd, J = 8.0, 1.8 Hz, 1H), 7.61 (d, J = 1.7 Hz, 1H), 7.44 (tt, J = 8.5, 6.1 Hz, 1H), 7.25 (t, J = 8.3 Hz, 2H), 3.45 (q, J = 7.3 Hz, 8H), 1.36 (t, J = 9.1, 5.5, 1.9 Hz, 12H). Synthesis of bis(4-(tert-butyl)phenyl)iodonium 4-((2,6-difluorophenoxy)carbonyl)2-hydroxybenzenesulfonate (D4): D4
[0151] Tetraethylammonium 4-((2,6-difluorophenoxy)carbonyl)-2-hydroxybenzenesulfonate (4.20 g, 9.1 mmol) and bis(4-(tert-butyl)phenyl)iodonium acetate (3.70 g, 8.2 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (70 mL) and water (70 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and added to a stirred solution of methyl tert-butyl ether (500 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. Residual solvent was removed by storage in a vacuum oven at 35°C overnight to give product D4 (3.43 g, 58%) as a white solid. 1 H NMR (499 MHz, CDCl3) δ 7.85 - 7.83 (m, 4H), 7.51 (t, J = 1.1Hz, 1H), 7.42 (d, J = 1.0 Hz, 2H), 7.29 - 7.26 (m, 4H), 7.14-7.12 (m, J =8.5, 5.9 Hz, 1H), 6.97 - 6.92 (m, 2H), 1.18 (s, 18H). 19 F NMR (470 MHz, DMSO-d6) δ 126.06. Synthesis of tetraethylammonium 2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonic acid:
[0152] N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (18.40 g, 96 mmol) was added to a mixture of potassium 4-carboxy-2-hydroxybenzenesulfonate (20.50 g, 80 mmol), 2,4,6-triiodophenol (56.61 g, 120 mmol), tetraethylammonium chloride (26.51 g, 160 mmol), and 4-pyrrolylpyridine (590 mg, 4 mmol) in DMF (150 mL) at room temperature. The reaction was stirred for 3 hours. The reaction was then quenched by pouring the mixture into an aqueous solution of tetraethylammonium chloride (20% w / v, 750 mL). The resulting mixture was extracted with DCM (4 × 200 mL), and the combined organic layers were washed with an aqueous solution of tetraethylammonium chloride (20% w / v, 3 × 100 mL) and water (3 × 200 mL). The organic layers were dried over filter paper and concentrated under reduced pressure. The resulting residue was resuspended in acetone (100 mL) and added dropwise to a stirred solution of methyl tert-butyl ether (900 mL) to form a precipitate. The oily precipitate was separated by decantation of the mother liquor and washing with excess methyl tert-butyl ether. The residual solvent was removed by storing the product overnight in a vacuum oven at 35°C to give a product as a white solid (28.50 g, 44%). 1 ¹H NMR (499 MHz, DMSO-d6) δ 10.77 (s, 1H), 8.24 (s, 2H), 7.72 (d, J = 8.1 Hz, 1H), 7.63 (dd, J = 8.1, 1.8 Hz, 1H), 7.52 (d, J = 1.7 Hz, 1H), 3.19 (q, J = 7.3 Hz, 8H), 1.19 - 1.12 (m, 12H). Synthesis of tri-p-tolylsulfonium 2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonate (D5): D5
[0153] Tetraethylammonium 2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonate (4.0 g, 5 mmol) and tri-p-tolylsulfonium bromide (1.93 g, 5 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (50 mL) and water (50 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was doped with n-heptane to achieve a final ratio of n-heptane:DCM of 1:3. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and added to a stirred solution of n-heptane (500 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. Residual solvent was removed by storage in a vacuum oven at 35°C overnight to give product D5 (4.61 g, 94%) as a white solid. 1 ¹H NMR (499 MHz, DMSO-d6) δ 10.78 (s, 1H), 8.23 (s, 2H), 7.71 (d, J = 8.0 Hz, 1H), 7.67 (d, J = 8.5 Hz, 6H), 7.61 (dd, J = 8.1, 1.7 Hz, 1H), 7.57 (d, J = 8.2 Hz, 6H), 7.51 (d, J = 1.7 Hz, 1H), 2.43 (s, 9H). Synthesis of 5-phenyl-5H-dibenzo[b,d]thiophene-5-onthium-2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonate (D6): D6
[0154] Tetraethylammonium 2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonate (4.0 g, 5 mmol) and 5-phenyl-5H-dibenzo[b,d]thiophene-5-onium bromide (1.71 g, 5 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (50 mL) and water (50 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was doped with n-heptane to achieve a final ratio of n-heptane:DCM of 1:3. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and added to a stirred solution of n-heptane (500 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. The residual solvent was removed by storing the product in a vacuum oven at 35°C overnight to obtain product D6 (3.53 g, 76%) as a white solid. 1¹H NMR (499MHz, DMSO-d6) δ 10.77 (s, 1H), 8.52 (d, J = 7.9 Hz, 2H), 8.38 (d, J = 7.9 Hz, 2H), 8.23 (s, 2H), 7.95 (td, J = 7.6, 1.1 Hz, 2H), 7.79 - 7.66 (m, 4H), 7.64- 7.55 (m, 5H), 7.52 (d, J = 1.7 Hz, 1H). Synthesis of phenyl(3-(trifluoromethyl)phenyl)iodonium-2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonate (D7): D7
[0155] Tetraethylammonium 2-hydroxy-4-((2,4,6-triiodophenoxy)carbonyl)benzenesulfonate (6.70 g, 8.4 mmol) and phenyl(3-(trifluoromethyl)phenyl)iodonium chloride (3.38 g, 8.8 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (60 mL) and water (60 mL) at room temperature. Acetone (50 mL) was added and stirring was continued overnight. Stirring was stopped, and the two-phase mixture was separated into individual layers. The aqueous layer was back-extracted with DCM (3 × 50 mL), and the combined organic layers were washed with water (5 × 50 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (100 mL) and added to a stirred solution of n-heptane and methyl tert-butyl ether (1:1, 900 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. The residual solvent was removed by storing the product in a vacuum oven at 35°C overnight to obtain product D7 (2.58 g, 30%) as a white solid. 1 H NMR (499 MHz, DMSO-d6) δ 10.76 (s, 1H), 8.75 (s,1H), 8.55 (d, J = 8.1 Hz, 1H), 8.31 (d, J = 7.6 Hz, 2H), 8.24 (s, 2H), 8.05(d, J = 7.9 Hz, 1H), 7.76 (t, J = 8.0 Hz, 1H), 7.73 - 7.66 (m, 2H), 7.62 (dd,J = 8.1, 1.7 Hz, 1H), 7.56 (t, J = 7.8 Hz, 2H), 7.52 (d, J = 1.7 Hz, 1H). 19FNMR (470 MHz, DMSO-d6) δ -61.19. Synthesis of 2-(4-iodophenoxy)ethane-1-ol:
[0156] A mixture of 4-iodophenol (8.80 g, 40 mmol) and potassium carbonate (16.58 g, 120 mmol) in N,N-dimethylformamide (100 mL) was heated to 75°C. 2-bromoethanol (15 g, 120 mmol) was added cleanly to the reaction mixture, and the mixture was stirred for 3 hours. The reaction mixture was quenched by pouring in water (500 mL). Methyl tert-butyl ether (300 mL) was added, and the mixture was stirred for 15 minutes. The two-phase mixture was separated into individual layers, and the aqueous layer was extracted with methyl tert-butyl ether (2 × 100 mL). The combined organic layers were washed with an aqueous solution of potassium hydroxide (1 M, 3 × 100 mL) and water (3 × 100 mL), dried over filter paper, and concentrated under reduced pressure to give a product as a white solid (5.82 g, 55%). 1 ¹H NMR (499 MHz, DMSO-d⁶) δ 7.57 (dt, J = 9.0, 2.3 Hz, 2H), 6.78 (dt, J = 9.0, 2.2 Hz, 2H), 4.87 (t, J = 5.3 Hz, 1H), 3.95 (dd, J = 5.4, 4.6 Hz, 2H), 3.70 (q, J = 4.8 Hz, 2H). Synthesis of tetraethylammonium 2-hydroxy-4-((2-(4-iodophenoxy)ethoxy)carbonyl)benzenesulfonic acid:
[0157] N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (5.21 g, 27.2 mmol) was added to a mixture of potassium 4-carboxy-2-hydroxybenzenesulfonate (5.82 g, 22.7 mmol), 2-(4-iodophenoxy)ethane-1-ol (9.00 g, 34.1 mmol), tetraethylammonium chloride (7.52 g, 45.4 mmol), and 4-pyrrolidinylpyridine (170 mg, 1.1 mmol) in DMF (50 mL) at room temperature. The reaction was stirred for 3 hours and then quenched by pouring into an aqueous solution of tetraethylammonium chloride (20% w / v, 300 mL). The resulting mixture was extracted with DCM (4 × 50 mL), and the combined organic layers were washed with an aqueous solution of tetraethylammonium chloride (20% w / v, 3 × 50 mL) and water (3 × 50 mL). The organic layers were dried over filter paper and concentrated under reduced pressure. The resulting residue was resuspended in acetone (100 mL) and added dropwise to a stirred solution of methyl tert-butyl ether (900 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess methyl tert-butyl ether. Residual solvent was removed by storing in a vacuum oven at 35°C overnight to give a product as a white solid (2.80 g, 21%). 1 HNMR (499 MHz, DMSO-d6) δ 10.65 (s, 1H), 7.63 - 7.56 (m, 3H), 7.38 (dd, J =8.1, 1.7 Hz, 1H), 7.31 (d, J = 1.7 Hz, 1H), 6.85 (dt, J = 8.8, 2.0 Hz, 2H), 4.56 (t, J = 4.6 Hz, 2H), 4.32 (t, J = 4.5 Hz, 2H), 3.19 (q, J = 7.2 Hz, 8H), 1.15 (tt, J = 7.2, 1.8 Hz, 12H). Synthesis of tri-p-tolylsulfonium 2-hydroxy-4-((2-(4-iodophenoxy)ethoxy)carbonyl)benzenesulfonate (D8): D8
[0158] Tetraethylammonium 2-hydroxy-4-((2-(4-iodophenoxy)ethoxy)carbonyl)benzenesulfonate (2.80 g, 4.72 mmol) and tri-p-tolylsulfonium bromide (1.82 g, 4.72 mmol) were vigorously stirred for 3 hours in a two-phase mixture of DCM (50 mL) and water (50 mL) at room temperature. Stirring was stopped, and the two-phase mixture was separated into individual layers. The organic layer was doped with n-heptane to achieve a final ratio of n-heptane:DCM of 1:3. The organic layer was washed with water (5 × 20 mL), dried over filter paper, and concentrated under reduced pressure. The resulting residue was resuspended in acetone (20 mL) and added to a stirred solution of n-heptane (500 mL) to form a precipitate. The precipitate was separated by vacuum filtration and washing with excess n-heptane. The residual solvent was removed by storing the product in a vacuum oven at 35°C overnight to obtain product D8 (2.48 g, 69%), which was a colorless oil. 1 ¹H NMR (499 MHz, DMSO-d⁶) δ 10.67 (s, 1H), 7.67 (d, J = 8.5 Hz, 6H), 7.62–7.54 (m, 9H), 7.38 (dd, J = 8.0, 1.7 Hz, 1H), 7.31 (d, J = 1.7 Hz, 1H), 6.85 (dt, J = 8.9, 1.9 Hz, 2H), 4.57 (t, J = 4.5 Hz, 2H), 4.32 (t, J = 4.6 Hz, 2H), 2.43 (s, 9H). Preparation of photoresist polymer.
[0159] The chemical structures of the polymer (P1), quencher (Q1), and comparative photoacid generator (cD1) used in the examples and comparative examples are shown below. Polymer P1 was prepared using methods commonly available in the art, and quencher Q1 and comparative PAG cD1 were obtained from commercial sources. Preparation and processing of photoresist compositions
[0160] KrF photoresist compositions. Photoresist compositions were prepared by dissolving the solid components in a solvent using the materials and amounts shown in Tables 1 and 2, where amounts are expressed as wt% of 100 wt% of the total weight of solids. The total solids content of the photoresist compositions was 2.1 wt%. The solvent system contained propylene glycol monomethyl ether acetate (50 wt%) and 4-hydroxy-4-methyl-2-pentanone (50 wt%). Each mixture was shaken using a mechanical oscillator and then filtered through a PTFE disc filter with a pore size of 0.2 micrometers.
[0161] Photolithography evaluation was performed using a CLEAN TRAC ACT8 (TEL, Tokyo Electron Co.) wafer track. A 200 nm wafer used for photolithography testing was coated with AR™ 3 BARC (DuPont Electronics & Industries) and soft-baked at 205°C for 60 seconds to obtain a 70 nm film. Then, an AR™ 40A BARC (DuPont Electronics & Industries) coating was deposited on the AR™ 3 layer and soft-baked at 215°C for 60 seconds to form a second BARC layer with a thickness of approximately 80 nm. A photoresist composition was then coated onto the double BARC stack and soft-baked at 110°C for 60 seconds to obtain a photoresist film layer with a thickness of approximately 50 nm.
[0162] The wafer was exposed to 248 nm radiation using a mask with selective features on a CANON FPA-5000 ES4 scanner (NA = 0.8, outer sigma = 0.85, inner sigma = 0.57). After exposure at 100°C, the wafer was baked for 60 seconds, developed with MF™ CD26 TMAH developer (DuPont Electronics & Industries) for 60 seconds, rinsed with deionized (DI) water, and dried. The critical dimension (CD) linewidth of the formed pattern was measured using a HITACHI S-9380 CD-SEM. Linewidth roughness (LWR) values were determined by top-down SEM at an accelerating voltage of 800 volts (V), a probe current of 8.0 picoamperes (pA), a magnification of 200 Kx at 1.0 digital zoom, and a frame count of 64. LWR was measured in 40 nm steps over a 2 μm line length and reported as the average LWR of the measured area. The size energy (E) of these lines was determined based on CD measurements. 尺寸 ) and LWR. The pseudo-Z factor is reported as follows, and is determined according to Equation 1: Pseudo-Z factor = (E 尺寸 ) × (LWR) 2 Equation 1 where E 尺寸 millijoules per square centimeter (mJ / cm²) 2 The report, LWR is reported in nanometers (nm), and the pseudo-Z factor is reported in mJ × 10⁻¹⁰. -11 Report. The pseudo-Z factor (Z' factor) is a modified measure of photoresist performance based on the Z factor, a known parameter indicating RLS (resolution, line edge roughness, sensitivity) photoresist performance (see, for example, Wallow, T. et al., Proc. SPIE [International Society for Optics and Photonics Conference Proceedings] 6921, 69211F, 2008). The pseudo-Z factor is calculated at constant resolution (CD size). Table 1 Table 2
[0163] As shown in Tables 1 and 2, each of the photoresist examples PR1 to PR9 produces patterns with good contours (patterning quality). As shown in Table 2, the comparative photoresist example cPR1 contains a comparative photoacid generator cD1, which contains anionic perfluorobutane sulfonate and cationic bis(4-(tert-butyl)phenyl)iodonium. Photoresist examples PR8 and PR9 can be directly compared to cPR1 by direct comparison, as PR8 and PR9 each have the same polymer and quencher components as cPR1. The photoacid generators in the photoresist compositions PR8 and PR9 of the present invention each contain anionic 4-((2-fluorophenoxy)carbonyl)-2-hydroxybenzenesulfonate or 4-((2,6-difluorophenoxy)carbonyl)-2-hydroxybenzenesulfonate. The photoresists of examples PR8 and PR9 achieve better lithography performance, as shown by higher quality images with less LWR and a lower Z-factor compared to cPR1.
[0164] While this disclosure has been described in conjunction with exemplary embodiments now considered to be practical, it should be understood that the invention is not limited to the disclosed embodiments, but rather 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: one or more non-solvent-based, base-insoluble base materials present in an amount greater than 50% by weight of the total solids of the photoresist composition; and a non-polymeric ionic photoacid generating compound comprising an anion and an iodonium or sulfonium cation, wherein the anion is represented by formula (1): (1) Among them, In equation (1), Ar 1 Is it a single-ring or multi-ring C? 3-60 Aromatic groups, each L 1 Independently, it is a single bond or one or more divalent connecting groups, wherein L 1 Fluorine-free, each R 1 C is either substituted or unsubstituted independently. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, 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 6-30 aryloxy, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 Alkyl heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, or substituted or unsubstituted C 3-30 Heteroaryl groups, wherein at least one R 1 Replaced by halogens, each R 1 Optionally, it may further include one or more divalent linking groups as part of its structure, each Z 1 Independently contains an anionic stabilizing group, wherein at least one Z 1 It is configured to form an intramolecular noncovalent bond with a sulfonate anion group to form a ring with 5 to 8 atoms, wherein Z 1 Independently selected from -OH, -C(O)OH, -SH, -C(O)SH, -NHS(O)2R 2 -S(O)2R 2 -S(O)2NHS(O)2R 2 -CH (=NOH), or -B (R) 3 )2, each Z 1 Optionally, it may further include one or more divalent linking groups as part of its structure, each R 2 Independently selected from fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 heteroaryl, each R 3 Independently selected from hydrogen, fluorine, hydroxyl, substituted or unsubstituted C 1-20 Alkyl, substituted or unsubstituted C 1-20 Heteroalkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 heteroaryl, two R 1 Together with Ar 1 Forming a fused ring, wherein the fused ring optionally further comprises one or more divalent linking groups as part of its structure, a Z 1 And an R 1 Together with Ar 1 A fused ring is formed, wherein the fused ring optionally further comprises one or more divalent linking groups as part of its structure, each a being independently 1 or 2, b being an integer from 1 to 4, and c being an integer from 1 to 3; and a solvent.
2. The photoresist composition as claimed in claim 1, wherein, Each R 1 C is either substituted or unsubstituted independently. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Heterocyclic alkyl, substituted or unsubstituted C 6-30 aryl, or substituted or unsubstituted C 3-30 Heteroaryl, wherein at least one R 1 Replaced by halogens, and each R 1 Optionally, it may further include one or more divalent linking groups as part of its structure.
3. The photoresist composition as described in claim 1, wherein, Each Z 1 It is configured to form an intramolecular noncovalent bond with the sulfonate anion group to form a ring with 6 or 7 atoms.
4. The photoresist composition of claim 1, wherein, Each anion stabilizing group has a pKa of 25 or less.
5. The photoresist composition of claim 1, wherein, Each anion-stabilizing group contains a group that acts as a proton.
6. The photoresist composition of claim 1, wherein, The anion does not contain trifluoromethyl and difluoromethylene.
7. The photoresist composition of claim 6, wherein, The at least one R 1 It can be replaced by fluorine, iodine, or a combination thereof.
8. The photoresist composition of claim 1, wherein, Ar 1 It is a single-ring C 3-6 Aromatic group, and at least one Z 1 Located in -L 1 -SO3 - The adjacent position of the indicated group.
9. The photoresist composition of claim 1, wherein, Ar 1 It is a multi-cyclic C 6-60 Aromatic groups.
10. The photoresist composition of claim 9, wherein, At least one Z 1 Groups bonded to Ar 1 Located on the same ring by -L 1 -SO3 - The cyclic carbon atom located adjacent to the group indicated.
11. The photoresist composition of claim 9, wherein, Ar 1 It is a fused polycyclic C 6-60 Aromatic groups, at least one Z 1 Groups bonded to Ar 1 The relative to -L 1 -SO3 - The bonded cyclic carbon atom is located at the β-position of the cyclic carbon atom, and the at least one Z 1 Groups and -L 1 -SO3 - Bonded to the fused polycyclic C 6-60 Different rings of aromatic groups.
12. The photoresist composition of claim 1, wherein, The conjugate acid of the non-polymeric ionic photoacid generating compound has a pKa of 0 or less.
13. The photoresist composition of claim 1, wherein, The non-solvent, alkali-insoluble base material includes polymers.
14. The photoresist composition of claim 13, wherein, The non-solvent, alkali-insoluble base material includes chain-breakable polymers, chain-degrading polymers, or combinations thereof.
15. The photoresist composition of claim 1, wherein, The non-solvent, alkali-insoluble base materials include metal-containing materials.
16. The photoresist composition of claim 1, wherein, At least one R 1 It is the replacement of C 6-30 The aryl group may optionally further comprise one or more divalent linking groups as part of its structure.
17. The photoresist composition of claim 1, wherein, c is 1 and L 1 It is a single key.
18. The photoresist composition of claim 1, wherein, The photoresist composition does not contain a photoacid generator that produces photoacids with a higher acidity than those produced by the ionic photoacid generator compound.
19. The photoresist composition of claim 1, wherein, The non-polymeric ionic photoacid generating compound contains an anion represented by formula (4a): (4a) Wherein, in formula (4a), L is a single bond or a divalent linking group containing 1 to 10 carbon atoms; each R 4 Independently, it is a hydroxyl, halogen, substituted or unsubstituted C. 1-30 Alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 3-30 Heterocyclic alkyl, 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 6-30 aryloxy, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 Alkyl heteroaryl, substituted or unsubstituted C 4-30 Heteroarylalkyl, or substituted or unsubstituted C 3-30 Heteroaryloxy groups; and each R 4 Optionally, it may further include one or more divalent linking groups as part of its structure; m is an integer from 0 to 4; and k is an integer from 1 to 5.
20. A patterning method, the method comprising: A layer of the photoresist composition as described in claim 1 is applied to a substrate to provide a photoresist composition layer; The photoresist composition layer is exposed to activation radiation in a patterned manner to provide exposure to the photoresist composition layer; And develop the exposed photoresist composition layer to provide a photoresist relief image.
Citation Information
Patent Citations
Radiation-sensitive copying composition
US4189323A
Compound, resin, resist composition and method for producing resist pattern
US8431325B2