Photoresist composition and pattern forming method

Abstract

Disclosed herein is a photoresist composition comprising: a first polymer formed by free radical polymerization, the first polymer comprising polymerized units formed from a monomer comprising an ethylenically unsaturated double bond and an acid-labile group; a photoacid generator; and a quencher having the formula (1): #imgabs0# wherein: R1 is independently a hydrogen atom, C1-C 20 Straight chain, C3‑C 20 Branched or C 3‑20 Cyclic alkyl groups - the alkyl groups optionally contain an -O- group in addition to the α-position relative to the amide C(O), or a C6-C 20 Aryl; R2 is independently a hydrogen atom, C1-C 20 Straight chain, C3‑C 20 Branched or C3‑C 20 Cyclic alkyl, or C6-C 20 Aryl; L is C1-C 20 Straight chain or C3‑C 20 A branched alkylene group comprising one or more heteroatom-containing groups independently selected from -O-, -S- or -N(R3)-, wherein R3 is selected from a hydrogen atom or a C1-C 20 Straight chain or C3‑C 20 a branched or cyclic alkyl group; each of R1, R2 and L can independently be substituted or unsubstituted; wherein the quencher does not contain a cross-linkable group; and a solvent.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 058,953, filed on July 30, 2020, the entire disclosure of which is incorporated herein by reference. Background Art

[0003] The present disclosure relates to photoresist compositions comprising a diamide quencher and pattern forming methods using such photoresist compositions. More specifically, photoresist compositions are particularly useful in the electronics industry for fabricating semiconductor devices.

[0004] Photoresist materials are photosensitive compositions used to transfer an image to one or more underlying layers, such as metal, semiconductor, or dielectric layers, disposed on a semiconductor substrate. To increase the integration density of semiconductor devices and allow the formation of structures with dimensions in the nanometer range, photoresists and photolithography processing tools with high-resolution capabilities have been and continue to be developed.

[0005] Chemically enhanced photoresists are commonly used for high-resolution processing. Such resists typically use polymers and photoacid generators with acid-labile groups. Patterned exposure to activating radiation through a photomask causes the acid generator to form an acid, which, during post-exposure baking, causes the acid-labile groups in the exposed areas of the polymer to crack. This creates a difference in solubility characteristics between the exposed areas and the unexposed areas of the resist in the developer solution. In the positive tone development (PTD) process, the exposed areas of the photoresist layer become soluble in the developer and are removed from the substrate surface, while the unexposed areas that are insoluble in the developer are retained to form a positive image after development. In the negative tone development (NTD) process, the exposed areas of the photoresist layer become insoluble in the developer and are retained to form a negative image after development. The resulting relief image allows selective processing of substrates. See, for example, Chemistry and Lithography by Uzodinma Okoroanyanwu, SPIE Press and John Wiley & Sons, 2010, and Fundamental Principles of Optical Lithography by Chris Mack, John Wiley & Sons, 2007.

[0006] One approach to achieving nanoscale feature sizes in semiconductor devices is to use short wavelength light, for example, light of 248 nanometers (nm) or less, during exposure of a chemically amplified photoresist. To further improve lithographic performance, immersion lithography tools have been developed to effectively increase the numerical aperture (NA) of the lens of an imaging device (e.g., a scanner with a KrF (248 nm) or ArF (193 nm) light source). This is accomplished by using a relatively high refractive index fluid (typically water) between the final surface of the imaging device and the upper surface of the semiconductor wafer. However, as lithographic resolution becomes increasingly higher, the line width roughness (LWR), critical dimension uniformity (CDU), and depth of focus (DoF) of the photoresist pattern have become increasingly important in forming high-fidelity patterns.

[0007] During the photolithography process, it is important to tightly control the focus of the light source entering the film because this largely determines the vertical concentration of the acid produced from the photoacid generator. This in turn affects the critical dimension (CD) of the pattern and the generation of LWR and defects. Although photolithography tools have become increasingly precise in controlling the focus point of the light, it is also desirable for the photoresist to exhibit a wide depth of focus. The depth of focus is the tolerance for unwanted variations in focus within the photoresist layer, which results in an acceptable variation in the CD of the obtained pattern, typically + / - 10% CD. To this end, the diffusion of the photogenerated acid within the photoresist layer is precisely controlled and should be matched to balance other resist properties, such as the speed of light. If the acid diffuses too quickly or unevenly, areas of the film may exhibit differences in acid concentration, which can lead to differences in CD and LWR and may produce defects.

[0008] There are examples of photoresist compositions with improved depth of focus and controlled acid diffusion in the literature. For example, U.S. Patent No. 9,513,549 discloses a photoresist composition having a polymer matrix containing protected polar groups. The document discloses that a wider depth of focus is observed due to the improved acid diffusion control of the photoresist.

[0009] There is a need in the art for photoresist compositions and patterning methods useful in electronic device fabrication that address one or more problems associated with the prior art. Summary of the Invention

[0010] Disclosed herein is a photoresist composition comprising: a first polymer formed by free radical polymerization, the first polymer comprising polymerized units formed from a monomer comprising an ethylenically unsaturated double bond and an acid-labile group; a photoacid generator; and a quencher having formula (1):

[0011]

[0012] Wherein: R1 is independently a hydrogen atom, C1-C20 Straight chain, C3-C 20 Branched or C 3-20 Cyclic alkyl - the alkyl group optionally contains an -O- group in addition to the α-position relative to the amide C(O), or a C6-C 20 Aryl; R2 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C3-C 20 Cyclic alkyl, or C6-C 20 Aryl; L is C1-C 20 Straight chain or C3-C 20 A branched alkylene group comprising one or more heteroatom-containing groups independently selected from -O-, -S- or -N(R3)-, wherein R3 is selected from a hydrogen atom or a C1-C 20 Straight chain or C3-C 20 a branched or cyclic alkyl group; each of R1, R2 and L can independently be substituted or unsubstituted; wherein the quencher does not contain a cross-linkable group; and a solvent. DETAILED DESCRIPTION

[0013] As used herein, the terms "a, an" and "the" do not indicate a limitation of quantity and are interpreted as including both the singular and the plural, unless otherwise indicated herein or clearly contradicted by the context. Unless expressly indicated otherwise, "or" means "and / or".

[0014] As used herein, " acid-labile group " refers to following group, wherein by the catalytic action of acid (optionally and typically together with thermal treatment) make key rupture, cause polar group (as carboxylic acid or alcohol group, form on polymer) and optionally and typically, the part of the key that is connected to rupture that disconnects with polymer.This acid is typically the photogenerated acid that occurs under the situation of key cleavage during the exposure back baking.Suitable acid-labile group comprises, for example: tertiary alkyl ester group, secondary or tertiary aryl ester group, there is secondary or tertiary ester group, tertiary alkoxy, acetal group or ketal group of the combination of alkyl and aryl.Acid-labile group is also referred to as " acid cleavable group ", " acid cleavable blocking group ", " acid-labile blocking group ", " acid leaving group ", " acid decomposable group " and " acid sensitive group " usually in this area.

[0015] "Substituted" means that at least one hydrogen atom on a group is replaced by another atom or group, provided that the normal valence of the designated atom is not exceeded. When the substituent is an oxo group (i.e., =O), then two hydrogens on the carbon atom are replaced. Combinations of substituents or variables are permissible. Exemplary groups that may be present in a "substituted" position include, but are not limited to, nitro (-NO2), cyano (-CN), hydroxyl (-OH), oxo (=O), amino (-NH2), mono- or di- (C 1-6 ) alkylamino, alkanoyl (such as C 2-6 Alkanoyl such as acyl), formyl (-C(=O)H), carboxylic acid or its alkali metal or ammonium salt; ester (including acrylate, methacrylate and lactone) such as C 2-6 Alkyl esters (-C(=O)O-alkyl or -OC(=O)-alkyl) and C 7-13 Aryl ester (-C(=O)O-aryl or -OC(=O)-aryl); amide (-C(=O)NR2, where R is hydrogen or C 1-6 alkyl), carboxamido (-CH2C(=O)NR2, wherein R is hydrogen or C 1-6 alkyl), halogen, mercapto (-SH), C 1-6 Alkylthio (-S-alkyl), thiocyano (-SCN), C 1-6 Alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Halogenated alkyl, C 1-9 Alkoxy, C 1-6 Halogenated alkoxy, C 3-12 Cycloalkyl, C 5-18 Cycloalkenyl, C 6-12 Aryl (e.g., phenyl, biphenyl, naphthyl, etc., each ring is substituted or unsubstituted aromatic), C having 1 to 3 separate or fused rings and 6 to 18 ring carbon atoms 7-19 Arylalkyl, arylalkoxy having 1 to 3 separate or fused rings and 6 to 18 ring carbon atoms, C 7-12 Alkyl aryl, C 4-12 Heterocycloalkyl, C 3-12 Heteroaryl, C 1-6 Alkylsulfonyl (-S(=O)2-alkyl), C 6-12 Arylsulfonyl (-S(=O)2-aryl), or tosyl (CH3C6H4SO2-). When a group is substituted, the number of carbon atoms indicated is the total number of carbon atoms in the group, excluding those of any substituents. For example, the group -CH2CH2CN is a C2 alkyl substituted with a cyano group.

[0016] Disclosed herein is a photoresist composition comprising: a first polymer formed by free radical polymerization, the first polymer comprising polymerized units formed from a monomer comprising an ethylenically unsaturated double bond and an acid-labile group;

[0017] A photoacid generator; a solvent; and a diamide quencher containing a heteroatom in the bridge that bonds the two amide groups. In embodiments, the heteroatom may comprise oxygen, nitrogen, sulfur, or a combination thereof. It is believed that the presence of the two amide groups and the heteroatom-containing linker in the quencher can effectively quench (neutralize) the photogenerated acid (which would otherwise diffuse from exposed resist layer areas to unexposed resist layer areas), allowing for desirable properties such as increased depth of focus and reduced roughness.

[0018] The first polymer is an acid-sensitive polymer (it is preferably formed by free radical polymerization) and comprises a polymerized unit formed by a monomer comprising an ethylenically unsaturated double bond and an acid-labile group. The first polymer is typically a copolymer comprising two or more different repeating units. The copolymer can be a random copolymer, a block copolymer, a star-shaped block copolymer, a gradient copolymer, etc., wherein preferably a random copolymer.

[0019] The monomer comprising an acid labile group may have formula (1a), (1b), (1c) or (1d):

[0020]

[0021] In formulas (1a) and (1b), R c and R d are each independently hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R c is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl).

[0022] In formula (1a), L 2 is a divalent linking group comprising at least one carbon atom, at least one heteroatom or a combination thereof. For example, L 2 May include 1 to 10 carbon atoms and at least one heteroatom. In an embodiment, L 2 It can be -OCH2-, -OCH2CH2O- or -N(R 41 )-, where R 41 is hydrogen or C 1-6 alkyl.

[0023] In formulas (1a) and (1b), R 1 to R 6are each independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 3-20 Heterocycloalkyl, linear or branched C 2-20 Alkenyl, monocyclic or polycyclic C 3-20 Cycloalkenyl, monocyclic or polycyclic C 3-20 Heterocycloalkenyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 4-20 heteroaryl, each of which is substituted or unsubstituted; provided that R 1 to R 3 Only one of them can be hydrogen and R 4 to R 6 Only one of them can be hydrogen. Preferably, R 1 to R 6 Each independently is a linear or branched C 1-6 Alkyl, or monocyclic or polycyclic C 3-10 cycloalkyl, each of which is substituted or unsubstituted.

[0024] In formula (1a), R 1 to R 3 Any two of together optionally form a ring, and R 1 to R 3 Each of which may optionally include as part of its structure a radical selected from -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 42 )-S(O)2-, wherein R 42 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl. In formula (1b), R 4 to R 6 Any two of together optionally form a ring, and R 4 to R 6 Each of which may optionally include as part of its structure a radical selected from -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 43 )-S(O)2-, wherein R 43 is hydrogen, straight-chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl. For example, R 1 to R 6Any one or more of may independently be of the formula -CH2C(=O)CH (3-n) Y n wherein each Y is independently substituted or unsubstituted C 3-10 heterocycloalkyl and n is 1 or 2. For example, each Y can independently be a substituted or unsubstituted radical comprising a radical having the formula -O(C a1 )(C a2 )O- 3-10 Heterocycloalkyl, wherein C a1 and C a2 are each independently hydrogen or substituted or unsubstituted alkyl, and wherein C a1 and C a2 together optionally forming a ring.

[0025] In formula (1c), R 7 to R 8 can be independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 3-20 Heterocycloalkyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 4-20 heteroaryl, each of which is substituted or unsubstituted; and R 9 Is a straight chain or branched chain C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl, each of which is substituted or unsubstituted. Optionally, R 7 or R 8 One of the R 9 Together they form a heterocyclic ring. Preferably, R 7 and R 8 can be independently hydrogen, a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl.

[0026] In formula (1d), R 10 to R 12 C can be independently linear or branched 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 3-20 Heterocycloalkyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 4-20 heteroaryl, each of which is substituted or unsubstituted, R 10 to R 12Any two of together optionally form a ring, and R 10 to R 12 Each of which optionally may contain as part of its structure a radical selected from -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 44 )-S(O)2-, wherein R 44 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl; X a is a polymerizable group selected from vinyl and norbornyl; and L 3 is a single bond or a divalent linking group, provided that when X a When it is vinyl 3 is not a single bond. Preferably, L 3 Is a monocyclic or polycyclic C 6-30 Arylene, or monocyclic or polycyclic C 6-30 Cycloalkylene, each of which may be substituted or unsubstituted. In formula (1d), n is 0 or 1. It should be understood that when n is 0, L 3 The group is directly attached to the oxygen atom.

[0027] Non-limiting examples of monomer (1a) include:

[0028]

[0029] Non-limiting examples of monomers having formula (1b) include:

[0030]

[0031]

[0032]

[0033] where R d is as defined above; and R' and R" are each independently a linear or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, monocyclic or polycyclic C 3-20 Heterocycloalkyl, linear or branched C 2-20 Alkenyl, monocyclic or polycyclic C 3-20 Cycloalkenyl, monocyclic or polycyclic C 3-20 Heterocycloalkenyl, monocyclic or polycyclic C 6-20 Aryl, or monocyclic or polycyclic C 4-20 heteroaryl, each of which is substituted or unsubstituted.

[0034] Non-limiting examples of monomers having formula (1c) include:

[0035]

[0036] where R d is as defined above.

[0037] Non-limiting examples of monomer (1d) include:

[0038]

[0039] In yet another example, the monomer comprising an acid labile group can have, for example, a cyclic acetal group or a cyclic ketal group having the formula:

[0040]

[0041] where R d is as defined above.

[0042] In yet another example, the monomer comprising an acid labile group can have a tertiary alkoxy group, for example, having the formula:

[0043]

[0044] The repeating units containing an acid labile group are typically present in the first polymer in an amount of 25 to 70 mole percent (mol%), typically 30 to 50 mol%, more typically 30 to 45 mol%, based on the total repeating units in the first polymer.

[0045] In an exemplary embodiment, the first polymer is a (meth)acrylate polymer.

[0046] The first polymer typically comprises one or more additional repeating units that are different from the first repeating unit. Suitable additional repeating units can include, for example, one or more additional units for the purpose of adjusting the properties (such as etching rate and solubility) of the photoresist composition. Exemplary additional units can include one or more of (meth)acrylates, vinyl ethers, vinyl ketones and vinyl esters. One or more additional repeating units (if present in the first polymer) can be used in an amount of up to 70 mol%, typically 3 to 50 mol%, based on the total repeating units of the first polymer. Suitable additional repeating units include, for example, repeating units comprising lactone groups, repeating units comprising alkali soluble groups, repeating units comprising polar groups, repeating units comprising diamide quenchers of the present invention as described below, and one or more combinations thereof.

[0047] Suitable repeat units comprising a lactone group may be derived from monomers having formula (2):

[0048]

[0049] In formula (2), R f is hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R f is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl). 4 It may be a single bond or a divalent linking group comprising one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 1-30 Heteroalkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted C 7-30 Arylalkylene, or substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted C 3-30 Heteroarylalkylene, wherein L 4 Optionally, it may further comprise a group selected from, for example, -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 44 )-S(O)2-, wherein R 44 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl. 14 C can be monocyclic, polycyclic or fused polycyclic 4-20 Lactone-containing groups.

[0050] Non-limiting examples of lactone group-containing monomers having formula (2) include:

[0051]

[0052] where R f As disclosed herein.

[0053] For polymeric units containing alkali-soluble groups, the alkali-soluble groups have a pKa less than or equal to 12, preferably from 2 to 12, more preferably from 3 to 9, and most preferably from 4 to 8. The pKa is typically measured in aqueous solution at 25°C and can be determined experimentally, for example, by potentiometric titration (e.g., by using a potentiometric pH meter available from Sirius Analytical Instruments Ltd), or can be calculated, for example, by using Advanced Chemical Developments (ACD) Labs software version 11.02. When measuring the acid value of a functional group with a relatively high pKa, such as a -C(CF3)2OH group, a non-aqueous titrant (such as an organic solvent or a mixture of organic solvents) can be used.

[0054] Suitable repeating units containing alkali soluble groups may be derived from monomers having formula (3):

[0055]

[0056] wherein the repeating unit has a pKa less than or equal to 12. g It can be hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R g is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl). Q 1 It can be one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted divalent C 7-30 Arylalkyl, substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted divalent C 3-30 Heteroarylalkyl or -C(O)-O-. W is an alkali soluble group and can be selected from, for example, -C(O)-OH; a fluorinated alcohol such as -C(CF3)2OH; an amide; an imide; or -NH-S(O)2-Y 1 , where Y 1 Is F or C 1-4 In formula (3), a is an integer of 1 to 3.

[0057] Non-limiting examples of monomers having formula (3) include:

[0058]

[0059] where R g and Y 1 is as described above.

[0060] Suitable repeating units containing polar groups may be derived from monomers having formula (4):

[0061]

[0062] In formula (4), R f is hydrogen, fluorine, cyano, substituted or unsubstituted C 1-10 Alkyl, substituted or unsubstituted C 1-10 Preferably, R f is hydrogen, fluorine, or substituted or unsubstituted C 1-5 Alkyl (typically methyl). 4 It may be a single bond or a divalent linking group comprising one or more of the following: substituted or unsubstituted C 1-30 Alkylene, substituted or unsubstituted C 1-30 Heteroalkylene, substituted or unsubstituted C 3-30 Cycloalkylene, substituted or unsubstituted C 1-30 Heterocycloalkylene, substituted or unsubstituted C 6-30 Arylene, substituted or unsubstituted C 7-30 Arylalkylene, or substituted or unsubstituted C 1-30 Heteroarylene, or substituted or unsubstituted C 3-30 Heteroarylalkylene, wherein L 4 Optionally, it may further comprise a group selected from, for example, -O-, -C(O)-, -C(O)-O-, -S-, -S(O)2-, and -N(R 44 )-S(O)2-, wherein R 44 It can be hydrogen, straight chain or branched C 1-20 Alkyl, monocyclic or polycyclic C 3-20 Cycloalkyl, or monocyclic or polycyclic C 3-20 Heterocycloalkyl. 15 It can be a polar group, such as a hydroxyalkyl group (e.g., a C1-C12 group substituted with one or more hydroxyl or cyano groups). 15 alkyl).

[0063] Non-limiting examples of monomers having formula (4) include:

[0064]

[0065] Exemplary copolymers useful as the first polymer include, for example, the following:

[0066]

[0067]

[0068] The first polymer typically has a weight average molecular weight M of 1,000 to 50,000 Daltons (Da), specifically 2,000 to 30,000 Da, more specifically 3,000 to 20,000 Da, still more specifically 3,000 to 10,000 Da. w The molecular weight is determined by GPC using polystyrene standards. The first polymer is typically present in the photoresist composition in an amount of 50 to 97 weight percent (wt%), preferably 75 to 95 wt%, and more preferably 80 to 90 wt%, based on the total solids of the photoresist composition.

[0069] The first polymer is preferably prepared by free radical polymerization using techniques well known to those skilled in the art.

[0070] For example, one or more monomers corresponding to the repeating units described herein can be combined or fed separately using suitable one or more solvents and initiators and polymerized in a reactor. For example, the first polymer and the second polymer can be obtained by polymerization of the corresponding monomers under any suitable conditions, such as by heating at an effective temperature, irradiating with actinic radiation at an effective wavelength, or a combination thereof. Typically, once mixed and once the desired molecular weight is reached, the reaction mixture is allowed to cool and then poured into a non-solvent. The polymer precipitates from the non-solvent and can be collected by filtration, separated, and dried. The reaction mixture can also be simply concentrated by removing the reaction solvent.

[0071] The photoresist composition may further comprise one or more polymers in addition to and different from the first polymer described above. For example, the photoresist composition may comprise additional polymers as described above but having different compositions, or polymers similar to those described above but not comprising each of the essential repeating units. In addition or alternatively, the one or more additional polymers may include those well-known in the photoresist field, for example, those selected from the following: polyacrylates, polyvinyl ethers, polyesters, polynorbornenes, polyacetals, polyethylene glycols, polyamides, polyacrylamides, polyphenols, novolacs, styrenic polymers, polyvinyl alcohol, or a combination thereof.

[0072] The photoresist composition further comprises one or more photoacid generators (PAGs). Suitable photoacid generator compounds may have the formula G + A - , where G + is an organic cation and A -is an organic anion typically comprising a sulfonate, sulfonamide, sulfonimide or methide anion. Suitable organic anions include, for example, fluoroalkyl and alkylsulfonates, fluoro-cycloalkyl and cycloalkylsulfonates.

[0073]

[0074] Suitable organic cations include, for example, iodonium cations substituted with two alkyl groups, aryl groups, or a combination of alkyl and aryl groups; and sulfonium cations substituted with three alkyl groups, aryl groups, or a combination of alkyl and aryl groups. + is an iodonium cation substituted with two alkyl groups, aryl groups, or a combination of alkyl and aryl groups; or is a sulfonium cation substituted with three alkyl groups, aryl groups, or a combination of alkyl and aryl groups. In some embodiments, G + is a substituted sulfonium cation having the following formula (5A) or an iodonium cation having the following formula (5B):

[0075]

[0076] Among them, each R aa Independently C 1-20 Alkyl, C 1-20 Fluoroalkyl, C 3-20 Cycloalkyl, C 3-20 Fluorocycloalkyl, C 2-20 Alkenyl, C 2-20 Fluoroalkenyl, C 6-30 Aryl, C 6-30 Fluoroaryl, C 6-30 Iodoaryl, C 1-30 Heteroaryl, C 7-20 Arylalkyl, C 7-20 Fluoroarylalkyl, C 2-20 Heteroarylalkyl, or C 2-20 Fluoroheteroarylalkyl, each of which is substituted or unsubstituted, wherein each R aa is separated or connected to another group R via a single bond or a divalent linking group aa To form a ring. Each R aa Optionally, it may include as part of its structure one or more groups selected from the group consisting of: -O-, -C(O)-, -C(O)-O-, -C 1-12 Alkylidene-, -O-(C 1-12 alkylene)-、-C(O)-O-(C 1-12 alkylene)- and -C(O)-O-(C 1-12 Each R aaIndependently, it may optionally contain an acid labile group selected from, for example, a tertiary alkyl ester group, a secondary or tertiary aryl ester group, a secondary or tertiary ester group having a combination of alkyl and aryl groups, a tertiary alkoxy group, an acetal group, or a ketal group. aa The divalent linking group of the group includes, for example, -O-, -S-, -Te-, -Se-, -C(O)-, -C(S)-, -C(Te)- or -C(Se)-, substituted or unsubstituted C 1-5 Alkylene, and combinations thereof.

[0077] Exemplary sulfonium cations having formula (5A) include the following:

[0078]

[0079]

[0080] Exemplary iodonium cations having formula (5B) include the following:

[0081]

[0082]

[0083] The PAG can be present in the photoresist composition in a non-polymeric form or in a polymeric form, for example as part of the first polymer or a different polymer. Suitable PAGs are known in the art of chemically amplified photoresists and include, for example, onium salts such as triphenylsulfonium trifluoromethanesulfonate, (p-tert-butoxyphenyl)diphenylsulfonium trifluoromethanesulfonate, tris(p-tert-butoxyphenyl)sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium (adamantan-1-ylmethoxycarbonyl)-difluoromethanesulfonate, and triphenylsulfonium camphorsulfonate; di-tert-butylphenyliodonium perfluorobutanesulfonate and di-tert-butylphenyliodonium camphorsulfonate. Also known are nonionic sulfonates and sulfonyl compounds that act as photoacid generators, such as nitrobenzyl derivatives, for example, 2-nitrobenzyl-p-toluenesulfonate, 2,6-dinitrobenzyl-p-toluenesulfonate, and 2,4-dinitrobenzyl-p-toluenesulfonate; sulfonic acid esters, for example, 1,2,3-tris(methylsulfonyloxy)benzene, 1,2,3-tris(trifluoromethylsulfonyloxy)benzene, and 1,2,3-tris(p-toluenesulfonyloxy)benzene; diazomethane derivatives, for example, bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane; glyoxime derivatives, for example, bis-O-(p-toluenesulfonyl)diazomethane; )-α-dimethylglyoxime, and bis-O-(n-butanesulfonyl)-α-dimethylglyoxime; sulfonate derivatives of N-hydroxyimide compounds, such as N-hydroxysuccinimide methanesulfonate, N-hydroxysuccinimide trifluoromethanesulfonate; and halogen-containing triazine compounds, such as 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, triphenylsulfonium(adamantan-1-ylmethoxycarbonyl)-difluoromethanesulfonate, triphenylsulfonium camphorsulfonate, and 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine. Suitable photoacid generators are further described in U.S. Patent No. 8,431,325 to Hashimoto et al. at column 37, lines 11-47 and columns 41-91. Other suitable sulfonate PAGs include sulfonated esters and sulfonyloxyketones, nitrobenzyl esters, s-triazine derivatives, benzoin tosylate, α-(p-toluenesulfonyloxy)-tert-butylphenyl acetate, and α-(p-toluenesulfonyloxy)-tert-butyl acetate; as described in U.S. Patent Nos. 4,189,323 and 8,431,325. Typically, the photoacid generator is present in the photoresist composition in an amount of 2 to 65 wt%, more typically 5 to 55 wt%, and more preferably 8 to 25 wt%, based on the total solids of the photoresist composition.

[0084] The photoresist composition further contains a quencher having a structure of formula (6):

[0085]

[0086] Wherein R1 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C3-C 20 Cyclic alkyl - the alkyl group optionally contains an -O- group in addition to the α-position relative to the amide C(O), or a C6-C 20 Aryl; R2 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C3-C 20 Cyclic alkyl, or C6-C 20 Aryl; L is C1-C 20 Straight chain or C3-C 20 A branched alkylene group comprising one or more heteroatom-containing groups independently selected from -O-, -S- or -N(R3)-, wherein R3 is selected from a hydrogen atom or a C1-C 20 Straight chain or C3-C 20 branched or cyclic alkyl; and wherein each of R1, R2 and L can be independently substituted or unsubstituted. Suitable substituents for R1, R2 and L include, for example, cyano, C 1-6 Cyanoalkyl, C 1-6 Alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Halogenated alkyl, C 1-9 Alkoxy, C 1-6 Halogenated alkoxy, C 3-12 Cycloalkyl, C 5-18 Cycloalkenyl, C 6-12 Aryl (e.g., phenyl, biphenyl, naphthyl, etc., each ring is substituted or unsubstituted aromatic), C having 1 to 3 separate or fused rings and 6 to 18 ring carbon atoms 7-19 Arylalkyl, arylalkoxy having 1 to 3 separate or fused rings and 6 to 18 ring carbon atoms, C 7-12 Alkyl aryl, C 4-12 Heterocycloalkyl, C 3-12 Heteroaryl, C 1-6 Alkylsulfonyl (-S(=O)2-alkyl), C 6-12 Arylsulfonyl (-S(=O)2-aryl), tosyl (CH3C6H4SO2-), or a combination thereof. When a group is substituted, the number of carbon atoms indicated is the total number of carbon atoms in the group, excluding those of any substituents. For example, the group -CH2CH2CN is a C2 alkyl substituted with a cyano group.

[0087] The quencher does not contain crosslinkable groups, such as hydroxyl, epoxy, carbamate and vinyl. As such, none of R1, R2 or L (whether substituted or unsubstituted) include crosslinkable groups. It is believed that the presence of such groups on the quencher will result in reaction with -COOH or -OH groups on the first polymer (which can be formed after the cracking of acid-labile groups on the polymer during exposure and post-exposure baking). This will cause the polarity conversion of the polymer in the exposed area of the photoresist layer to decrease, thereby reducing the contrast between the exposed area and the unexposed area of the photoresist layer.

[0088] The quencher is present in the photoresist composition to control the diffusion of photogenerated acid in the photoresist layer formed from the composition during the resist patterning process. It is believed that the presence of the two amide groups and the heteroatom-containing linker in the quencher of the present invention can effectively quench (neutralize) the photogenerated acid (which would otherwise diffuse from exposed resist layer areas to unexposed resist layer areas), allowing for the achievement of desirable properties such as increased depth of focus and reduced roughness.

[0089] As described above, the quencher can be in a non-polymeric form. Suitable quenchers of the present invention are commercially available and / or can be manufactured by one of ordinary skill in the art. The non-polymeric quencher is typically present in the photoresist composition in an amount of 0.01 to 5 wt %, preferably 0.02 to 3 wt %, based on the total solids of the photoresist composition. An exemplary suitable non-polymeric quencher having formula (6) is shown below:

[0090]

[0091] The photoresist composition can further include a material (alkali unstable material) comprising one or more alkali unstable groups. As mentioned herein, the alkali unstable group is a functional group that can undergo a cleavage reaction to provide a polar group (such as a hydroxyl, carboxylic acid, sulfonic acid, etc.) in the presence of an aqueous alkali developer after the exposure step and the post-exposure baking step. The alkali unstable group will not undergo a significant reaction (such as a bond cleavage reaction) before the developing step of the photoresist composition comprising the alkali unstable group. Therefore, such as, the alkali unstable group will be substantially inert during the soft baking step before exposure, the exposure step, and the post-exposure baking step. "Substantially inert" means that ≤5%, preferably ≤1% of the alkali unstable group (or part) will split, break, or react during the soft baking step before exposure, the exposure step, and the post-exposure baking step. The alkali unstable group is reactive under the photoresist developing conditions of a typical aqueous alkali photoresist developer (such as a 0.26 standard (N) aqueous solution of tetramethylammonium hydroxide (TMAH)). In one embodiment, the present invention relates to a photoresist layer comprising a plurality of photoresist compositions comprising a plurality of photoresist compositions, wherein the plurality of photoresist compositions comprise a plurality of photoresist compositions, and a plurality of photoresist compositions comprising a plurality of photoresist compositions. The plurality of photoresist compositions comprising a ...

[0092] In some aspects, the base-labile material is a polymeric material (also referred to herein as a base-labile polymer) that can include one or more repeating units comprising one or more base-labile groups. For example, the base-labile polymer can include repeating units containing two or more identical or different base-labile groups. Preferred base-labile polymers include at least one repeating unit comprising 2 or more base-labile groups, for example, repeating units comprising 2 or 3 base-labile groups.

[0093] The base labile polymer may be a polymer comprising repeating units derived from a monomer having formula (7)

[0094]

[0095] where X b is a polymerizable group selected from vinyl and acrylic groups, L 5is a divalent linking group comprising one or more of the following: substituted or unsubstituted linear or branched C 1-20 Alkylene, substituted or unsubstituted C 3-20 Cycloalkylene, -C(O)- or -C(O)O-; and Rf is substituted or unsubstituted C 1-20 Fluoroalkyl group, provided that the carbon atom bonded to the carbonyl group (C=O) in formula (7) is substituted with at least one fluorine atom.

[0096] Exemplary monomers having formula (7) include the following:

[0097]

[0098] The base labile polymer may comprise repeating units comprising two or more base labile groups. For example, the base labile polymer may comprise repeating units derived from a monomer having formula (8)

[0099]

[0100] where X b and Rf are defined as in formula (7); L 6 is a polyvalent linking group comprising one or more of the following: substituted or unsubstituted linear or branched C 1-20 Alkylene, substituted or unsubstituted C 3-20 cycloalkylene, -C(O)- or -C(O)O-; and n is an integer of 2 or greater, for example, 2 or 3.

[0101] Exemplary monomers having formula (8) include the following:

[0102]

[0103] The base-labile polymer may comprise repeating units comprising one or more base-labile groups. For example, the base-labile polymer may comprise repeating units derived from a monomer having formula (9):

[0104]

[0105] where X b is defined as in formula (7); L 7 is a divalent linking group comprising one or more of the following: substituted or unsubstituted linear or branched C 1-20 Alkylene, substituted or unsubstituted C 3-20 Cycloalkylene, -C(O)- or -C(O)O-; L f is substituted or unsubstituted C 1-20 A fluoroalkylene group, wherein the carbon atom bonded to the carbonyl group (C=O) in formula (9) is substituted with at least one fluorine atom; and Rm is a substituted or unsubstituted straight or branched chain C 1-20 Alkyl, substituted or unsubstituted C 3-20 Cycloalkyl.

[0106] Exemplary monomers having formula (9) include the following:

[0107]

[0108] In another preferred aspect of the present invention, the unstable polymer of alkali can comprise one or more unstable groups of alkali and one or more unstable groups of acid, as one or more unstable ester moieties of acid (for example tert-butyl ester) or unstable acetal group of acid.For example, the unstable polymer of alkali can comprise the repeating unit that comprises unstable groups of alkali and unstable groups of acid, that is, wherein unstable groups of alkali and unstable groups of acid are both present on same repeating unit.In another example, the unstable polymer of alkali can comprise the first repeating unit that contains unstable groups of alkali and the second repeating unit that contains unstable groups of acid.Preferred photoresist of the present invention can show the defect relevant with the resist relief image formed by photoresist composition of reduction.

[0109] Alkali unstable polymers can be prepared using any suitable method in the art, including those described herein for the first and second polymers. For example, alkali unstable polymers can be obtained by polymerization of the corresponding monomers under any suitable conditions, such as by heating at an effective temperature, irradiating with actinic radiation under an effective wavelength, or a combination thereof. Additionally or alternatively, suitable methods can be used to graft one or more alkali unstable groups onto the backbone of the polymer. Alkali unstable polymers typically have a weight average molecular weight M of 1,000 to 50,000 Da, specifically 2,000 to 30,000 Da, more specifically 3,000 to 20,000 Da, and more specifically 3,000 to 10,000 Da. w The molecular weight is determined by GPC using polystyrene standards. In some aspects, the base labile material is a single molecule comprising one or more base labile ester groups, preferably one or more fluorinated ester groups. The base labile material that is a single molecule may have an M of 50 to 1,500 Da. W Exemplary single molecule base-labile materials include the following:

[0110]

[0111] The photoresist composition further comprises a solvent for dissolving the components of the composition and promoting its coating on the substrate. Preferably, the solvent is an organic solvent conventionally used in the manufacture of electronic devices. Suitable solvents include, for example: aliphatic hydrocarbons such as hexane 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 and 4-methyl-2-pentanol; 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. Ester, 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 non-cyclic carbonates such as propylene carbonate, dimethyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate and propylene carbonate; polar aprotic solvents such as dimethyl sulfoxide and dimethylformamide; water; and combinations thereof. Among these, preferred solvents are PGME, PGMEA, EL, GBL, HBM, CHO, and combinations thereof. The total solvent content in the photoresist composition (i.e., the cumulative solvent content of all solvents) is typically 40 to 99 wt %, for example 70 to 99 wt %, or 85 to 99 wt %, based on the total weight of the photoresist composition. The desired solvent content will depend, for example, on the desired thickness of the applied photoresist layer and the coating conditions.

[0112] The photoresist composition may further comprise one or more additional optional additives. For example, the optional additives may include one or more photodegradable quenchers (also known as photodegradable bases), basic quenchers other than the diamide quencher compounds described above, surfactants, resist stabilizers, actinic dyes and contrast dyes, anti-striation agents, plasticizers, speed enhancers, sensitizers, and the like, or combinations thereof. Unless otherwise stated below, 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.

[0113] The photodecomposable quencher generates a weak acid upon irradiation. The acid generated by the photodecomposable quencher is not strong enough to react rapidly with the acid-labile groups present in the resist matrix. Exemplary photodecomposable quenchers include, for example, photodecomposable cations, and preferably can also be used to prepare strong acid generator compounds but are not suitable for use with weak acids (pKa>1) such as, for example, C 1-20 Carboxylic acid or C 1-20Examples of the photodegradable quencher include those that are paired with an anion of a sulfonic acid (e.g., a succinic acid). Exemplary carboxylic acids include formic acid, acetic acid, propionic acid, tartaric acid, succinic acid, cyclohexanecarboxylic acid, benzoic acid, salicylic acid, and the like. Exemplary carboxylic acids include p-toluenesulfonic acid, camphorsulfonic acid, and the like. In a preferred embodiment, the photodegradable quencher is a photodegradable organic zwitterionic compound, such as diphenyliodonium-2-carboxylate.

[0114] Exemplary basic quenchers include, for example, linear aliphatic amines such as tributylamine, trioctylamine, triisopropanolamine, tetrakis(2-hydroxypropyl)ethylenediamine, n-tert-butyldiethanolamine, tris(2-acetoxyethyl)amine, 2,2',2",2"'-(ethane-1,2-diylbis(azanetriyl))tetraethanol, 2-(dibutylamino)ethanol, and 2,2',2"-nitrilotriethanol; cyclic aliphatic amines such as 1 -(tert-Butoxycarbonyl)-4-hydroxypiperidine, tert-butyl 1-pyrrolidinecarboxylate, tert-butyl 2-ethyl-1H-imidazole-1-carboxylate, di-tert-butyl piperazine-1,4-dicarboxylate and N-(2-acetoxy-ethyl)morpholine; aromatic amines such as pyridine, di-tert-butylpyridine and pyridinium; linear and cyclic amides and their derivatives such as N,N-bis(2-hydroxyethyl)palmitamide, N,N-diethylacetamide, N 1 ,N 1 ,N 3 ,N 3 -tetrabutylmalonamide, 1-methylazacycloheptan-2-one, 1-allylazacycloheptan-2-one and tert-butyl 1,3-dihydroxy-2-(hydroxymethyl)propan-2-ylcarbamate; ammonium salts such as quaternary ammonium salts of sulfonates, sulfamates, carboxylates and phosphonates; imines such as primary and secondary aldimines and ketimines; diazines such as optionally substituted pyrazines, piperazines and phenazines; diazoles such as optionally substituted pyrazoles, thiadiazoles and imidazoles; and optionally substituted pyrrolidones such as 2-pyrrolidone and cyclohexylpyrrolidine.

[0115] Exemplary surfactants include fluorinated and non-fluorinated surfactants and can be ionic or non-ionic, with non-ionic surfactants being preferred. Exemplary fluorinated non-ionic surfactants include perfluorinated C4 surfactants such as FC-4430 and FC-4432 surfactants available from 3M Corporation; and fluorodiols such as POLYFOX PF-636, PF-6320, PF-656, and PF-6520 fluorosurfactants from Omnova. In one aspect, the photoresist composition further includes a surfactant polymer containing fluorinated repeating units.

[0116] The photoresist composition can be prepared according to known procedures. For example, the composition can be prepared by dissolving the solid (non-solvent) components of the composition in one or more solvent components.

[0117] A patterning method using the photoresist composition of the present invention will now be described. Suitable substrates on which the photoresist composition can be applied include electronic device substrates. A wide variety of electronic device substrates can be used in the present invention, such as semiconductor wafers; polycrystalline silicon substrates; packaging substrates, such as multi-chip modules; flat panel display substrates; substrates for light-emitting diodes (LEDs) including organic light-emitting diodes (OLEDs); etc., with semiconductor wafers being typical. Such substrates are typically made of one or more of silicon, polycrystalline silicon, silicon oxide, silicon nitride, silicon oxynitride, silicon germanium, gallium arsenide, aluminum, sapphire, tungsten, titanium, titanium-tungsten, nickel, copper, and gold. Suitable substrates can be in the form of wafers, such as those used to manufacture integrated circuits, optical sensors, flat panel displays, integrated optical circuits, and LEDs. Such substrates can be of any suitable size. Typical wafer substrate diameters are 200 to 300 millimeters (mm), although wafers with smaller and larger diameters can be appropriately used according to the present invention. The substrate may include one or more layers or structures, which may optionally include an active or operable portion of the device being formed.

[0118] Typically, prior to coating the photoresist composition of the present invention, one or more photoresist layers, such as a hard mask layer (e.g., spin-on carbon (SOC), amorphous carbon, or a metal hard mask layer), a CVD layer (e.g., a silicon nitride (SiN), silicon oxide (SiO), or silicon oxynitride (SiON) layer), an organic or inorganic underlayer, or a combination thereof, are provided on the upper surface of the substrate. Such layers, together with the overcoated photoresist layer, form a photoresist material stack.

[0119] Optionally, an adhesion promoter layer can be applied to the substrate surface before applying the photoresist composition. If an adhesion promoter is desired, any suitable adhesion promoter for the polymer film can be used, such as a silane, typically an organosilane such as trimethoxyvinylsilane, triethoxyvinylsilane, hexamethyldisilazane, or an aminosilane coupling agent such as gamma-aminopropyltriethoxysilane. Particularly suitable adhesion promoters include those sold under the names AP 3000, AP 8000, and AP 9000S available from DuPont Electronics & Imaging (Marlborough, Massachusetts).

[0120] Can be by any suitable method, comprise that spin coating, spraying, dip coating, scraper etc. photoresist composition is coated on substrate.For example, applying photoresist layer can be by using coating track in solvent spin coating photoresist to complete, and wherein photoresist is distributed on the wafer of rotation.During distribution, wafer typically with up to 4,000 revs / min (rpm), for example 200 to 3,000rpm, for example 1,000 to 2, the speed rotation time period of 500rpm to obtain photoresist composition layer on substrate.It will be appreciated by those skilled in the art that the thickness of the layer through coating can be regulated by changing the solid content of rotational speed and / or composition.The thickness of the photoresist layer formed by composition of the present invention can be widely changed according to application.For some application, resist can have 10 to 400 nanometers (nm), preferably 15 to 200nm and more preferably 50 to 100nm dry layer thickness.

[0121] Next, the photoresist composition is typically soft-baked to minimize the solvent content in the layer, thereby forming a tack-free coating and improving the adhesion of the layer to the substrate. Soft baking is carried out, for example, on a hot plate or in an oven, where a hot plate is typical. The soft baking temperature and time will depend on, for example, the specific photoresist composition and thickness. The soft baking temperature is typically 70°C to 170°C, for example, 70°C to 150°C. The soft baking time is typically 10 seconds to 20 minutes, for example, 1 minute to 10 minutes or 1 minute to 5 minutes. One of ordinary skill in the art can easily determine the heating time based on the composition of the composition.

[0122] Next, the photoresist layer is exposed to activating radiation in a patterned manner to produce a solubility difference between the exposed area and the unexposed area. The photoresist composition mentioned herein is exposed to radiation that has an activating effect on the composition and shows that radiation can form a latent image in the photoresist composition. Exposure is typically carried out through a patterned photomask, and the photomask has optically transparent areas and optically opaque areas corresponding to the resist layer area to be exposed and the unexposed resist layer area respectively. Alternatively, this exposure can be carried out in a direct write method without a photomask, and the direct write method is typically used for electron beam lithography. Activating radiation typically has a wavelength less than 400nm, less than 300nm or less than 200nm, wherein preferably a wavelength of 248nm (KrF), 193nm (ArF) and 13.5nm (EUV) or electron beam lithography. The method can be used in immersion or dry (non-immersion) lithography. The exposure energy is typically 1 to 200 mJ / cm2. 2 ), preferably 10 to 100 mJ / cm 2 and more preferably 20 to 50 mJ / cm 2, which depends on the exposure tool and the components of the photoresist composition.

[0123] After exposing the photoresist layer, a post-exposure bake (PEB) of the exposed photoresist layer is performed. PEB can be performed, for example, on a hot plate or in an oven, with a hot plate being typical. The conditions for PEB will depend, for example, on the specific photoresist composition and layer thickness. PEB is typically performed at a temperature of 80°C to 150°C and for a time of 30 to 120 seconds. A latent image defined by polarity-switched regions (exposed regions) and polarity-unswitched regions (unexposed regions) is formed in the photoresist.

[0124] Then, with suitable developer, the exposed photoresist layer is developed to selectively remove those regions of the layer that are soluble in the developer while retaining insoluble regions, to form the photoresist pattern relief image of gained. In the case of positive development (PTD) process, the exposed regions of the photoresist layer are removed during development and unexposed regions are retained. On the contrary, in negative development (NTD) process, the exposed regions of the photoresist layer are retained during development and unexposed regions are removed. The application of developer can be completed by any suitable method, as described above for the application of photoresist compositions, wherein spin coating is typical. Developing time is the time period for effectively removing the soluble regions of the photoresist, wherein typically 5 to 60 seconds. Typically, development is carried out at room temperature.

[0125] Suitable developers for the PTD process include aqueous alkaline developers, such as quaternary ammonium hydroxide solutions, such as tetramethylammonium hydroxide (TMAH) (preferably 0.26 standard (N) TMAH), tetraethylammonium hydroxide, tetrabutylammonium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, etc. Suitable developers for the NTD process are based on organic solvents, meaning that the cumulative content of organic solvents in the developer is 50 wt% or more, typically 95 wt% or more, 95 wt% or more, 98 wt% or more, or 100 wt% based on the total weight of the developer. Suitable organic solvents for NTD developers include, for example, those selected from ketones, esters, ethers, hydrocarbons, and mixtures thereof. The developer is typically 2-heptanone or n-butyl acetate.

[0126] A coated substrate can be formed from the photoresist composition of the present invention. Such a coated substrate comprises: (a) a substrate having one or more layers to be patterned on its surface; and (b) a photoresist composition layer on the one or more layers to be patterned.

[0127] The photoresist pattern can be used as, for example, an etching mask, so that the pattern is transferred to one or more sequentially arranged lower layers by known etching techniques, typically dry etching (such as reactive ion etching). The photoresist pattern can be used, for example, for transferring the pattern to an underlying hard mask layer, which is then used as an etching mask for transferring the pattern to one or more layers below the hard mask layer. In another aspect, the photoresist pattern can be used as a mask for an ion implantation process, for example, for selectively introducing a dopant into the substrate surface. If the photoresist pattern does not have loss during pattern transfer or implantation process, it can be removed from substrate by known technology (such as oxygen plasma ashing). When used for one or more such patterning processes, the photoresist composition can be used to manufacture semiconductor devices, such as storage devices, processor chips (CPUs), graphics chips, optoelectronic chips, LEDs, OLEDs and other electronic devices.

[0128] The photoresist compositions disclosed herein are exemplified by the following non-limiting examples.

[0129] Examples

[0130] Example 1

[0131] The various reactants used in these examples are shown below.

[0132] Polymer P1

[0133] Polymer P-1 is a copolymer of the repeating units shown below.

[0134]

[0135] The values 0.4, 0.4 and 0.2 respectively show the mole fractions of the corresponding repeating units in the copolymer.

[0136] Photoacid generator PAG-1A

[0137] Two photoacid generators (triphenylsulfonium (adamantan-1-ylmethoxycarbonyl)-difluoromethanesulfonate) PAG-1A and (triphenylsulfonium camphorsulfonate) PAG-2A were used in the examples.

[0138]

[0139] The fluorinated polymer P-2 was prepared generally according to the procedure described in US 20180059545

[0140]

[0141] Polymer P-2 is a copolymer of the repeating units shown above. The values 0.06 and 0.94 show the mole fractions of the repeating units in the copolymer.

[0142] Quencher Q-6

[0143]

[0144] (Commercially available from Waco Chemicals).

[0145] All reactions were carried out under normal atmospheric conditions. All chemicals used were directly from suppliers. The nuclear magnetic resonance (NMR) spectra of all compounds were obtained on a 600MHz spectrometer. Chemical shifts were reported with respect to the δ (ppm) value of the internal deuterated acetone residual signal. Multiplicity was indicated by s (singlet), d (doublet), t (triplet), m (multiplet), dd (double two doublets), dt (double triplets), tt (triplet triplets), br (wide singlet). Purchase 2-[2-(2-aminoethoxy)ethoxy]ethanamine from Sigma-Aldrich, purchase acetic acid from FischerScientific.

[0146] Quencher (N,N-(ethane-1,2-diylbis(oxy)bis(ethane-2,1-diyl)diethylamide) (denoted as Q- 1) Synthesis.

[0147] In the round-bottom flask that 500mL is equipped with stirring rod, reflux condenser and thermometer, 2- [2- (2-aminoethoxy) ethoxy] ethylamine (10.0g, 0.067mol) (Sigma-Aldrich) is dissolved in the ethyl acetate of 100g. Concentrated acetic acid (0.4g, 0.0067mol) is added dropwise to the reaction mixture and they are stirred together at room temperature for 10 minutes.Then the temperature is raised to 77 DEG C and a clear solution is obtained. By 1H-NMR monitoring reaction conversion and after 20 hours, it is considered that the reaction is complete. The reaction mixture is cooled in a dry ice bath to provide a white precipitate, which is filtered on a Buchner funnel and washed with cold ethyl acetate (-4 DEG C, 50mL) and room temperature methyl tert-butyl ether (100mL). Under high vacuum, the precipitate is dried overnight to provide 10.7g of product (68%) as a white powder. 1 H-NMR (500 MHz-acetone-d6) 7.17 (br, 2H), 3.55 (s, 4H), 3.49 (t, 4H), 3.31 (q, 4H), 1.88 (s, 6H) ppm. 13 C-NMR (125 MHz-acetone-d6) 170.3, 70.94, 70.48, 39.9, 22.9 ppm.

[0148]

[0149] Quencher (N,N'-((ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl)bis(3-methoxypropionyl) Synthesis of amine (denoted as Q-2)

[0150] In the round-bottom flask that 500mL is equipped with stirring rod, reflux condenser and thermometer, 2-[2-(2-aminoethoxy) ethoxy] ethylamine (6.0g, 0.04mol) (Sigma-Aldrich) is dissolved in the 3-methoxypropionic acid methyl ester of 95.7g.Concentrated acetic acid (0.122g, 0.002mol) is added dropwise in reaction mixture and they are stirred together at room temperature 10 minutes.Then the temperature is increased to 90 ℃ and they are stirred together 18 hours.Reaction mixture is cooled in dry ice bath and white precipitate is provided, is filtered on Buchner funnel and washed with cold methyl tert-butyl ether (100mL).Precipitate is dried overnight under high vacuum and provides the product (77%) of 10.1g as white powder. 1 H-NMR(500MHz-acetone-d6)7.14(br,2H),3.59,(t,4H),3.56(s,4H),3.50(t,4H),3.33(q,4H),3.27(s,6H),2.38(t,4H)ppm. 13 C-NMR (125 MHz-acetone-d6) 171.1, 71.0, 70.5, 69.5, 58.6, 39.8, 37.3 ppm.

[0151]

[0152] Synthesis of Quencher N,N'-(oxybis(ethane-2,1-diyl))diethylamide (denoted as Q-3)

[0153] In a 100 mL round-bottom flask equipped with a stirring rod, a reflux condenser, a thermometer, and a nitrogen inlet, 2-(2-aminoethoxy)ethylamine (3.0 g, 28 mmol) was dissolved in 43 g of ethyl acetate. Concentrated acetic acid (0.17 g, 0.0028 mol) was added to the reaction mixture and stirred together at room temperature for 10 minutes. The temperature was then raised to 77° C. and the mixture was stirred by 1 The reaction was concentrated by H-NMR and the reaction was stopped after 29 hours. The crude mixture was passed through a basic aluminum column. The organic phase obtained was then concentrated and cooled in a dry ice bath to provide a white precipitate, which was filtered on a Buchner funnel. The precipitate was dried overnight under high vacuum to provide 2.0 g (37%) of the product as a white powder. 1 H-NMR (500MHz, CDCl3) δ6.47(s,2H),3.53(t,4H),3.41(q,4H),2.00(s,6H). 13 C-NMR (125MHz, CDCl3) δ23.2, 39.2, 69.6, 170.6.

[0154]

[0155] Synthesis of Quencher N,N'-(Thiobis(ethane-2,1-diyl))diethylamide (denoted as Q-4)

[0156] In a 100mL round-bottom flask equipped with a stirring rod, a reflux condenser, a thermometer and a nitrogen inlet, 2,2'-thiobis(ethyl-1-amine) (3.0g, 25.0mmol) was dissolved in 43g of ethyl acetate. Concentrated acetic acid (0.2g, 0.003mol) was added to the reaction mixture and stirred together at room temperature for 10 minutes. The temperature was then raised to 77°C and the reaction conversion was monitored by 1H-NMR, and the reaction was stopped after 29 hours. Methanol was added to the crude mixture until a clear solution was obtained and the mixture was passed through a basic aluminum column. The organic phase obtained was then concentrated and cooled in a dry ice bath to provide a white precipitate, which was filtered on a Buchner funnel. The product was recrystallized in ethyl acetate / methanol by slowly evaporating the solvent. The precipitate was dried overnight under high vacuum to provide 1.2g of product (18%) as a white powder. 1 H-NMR(400MHz,D2O)δ3.32(t,4H),2.65(t,4H),1.93(s,6H). 13 C NMR (125MHz, D2O) δ21.8, 30.4, 38.7, 174.2ppm.

[0157]

[0158] Q-1, Q-2, Q-3 and Q-4 are quenchers of the present invention, which are used in the compositions of the present invention, while quenchers Q-5 and Q-6 are comparative quenchers.

[0159] Synthesis of comparative quencher N-(3-acetamidopropyl)-N-methylacetamide (denoted as Q-5)

[0160] In a 100mL round-bottom flask equipped with a stirring rod, N-methylethane-1,2-diamine (2.96g, 0.04mol) and acetic anhydride (9.53g, 0.09mol) were stirred neat at room temperature for 72h. The reaction mixture was transferred to a separatory funnel and a 1:1 mixture of water and tert-butyl alcohol was added, followed by solid sodium hydroxide. The organic phase was dried over sodium sulfate, collected, and the solvent was removed using a rotary evaporator. Ammonium chloride (2mL) and tert-butyl alcohol were added to the residue. Acetone was added until no white precipitate formed. The precipitated product was separated and further dried in a vacuum pump to obtain 3.47g of the desired product. 1H-NMR (500 MHz-chloroform-d3) 6.82 (br, 1H), 3.45 (t, 2H), 3.18 (t, 2H), 2.97 (s, 3H), 2.05 (s, 3H), 1.98 (s, 3H), 1.62 (m, 2H) ppm.

[0161]

[0162] General preparation of photoresist compositions

[0163] Photoresist compositions (shown in Table 1 below) were prepared by mixing the components listed in Table 1. Each mixture was filtered through a 0.2 μm PTFE disk. The numbers in parentheses are parts by weight per hundred. Solvent-1 was propylene glycol methyl ether acetate (PGMEA) and solvent-2 was 2-hydroxyisobutyric acid methyl ester (HBM).

[0164] Table 1

[0165]

[0166] Photolithography

[0167] Photoresists made from the photoresist compositions of Table 1 were evaluated by photolithography. A 300 millimeter (mm) silicon wafer was first spin-coated with a bottom anti-reflective coating AR TM40 (DuPont Electronics & Imaging) and baked at 205°C for 60 seconds to form an 80 nanometer (nm) film. A silicon-containing n-type reflective coating was then spin-coated on top and baked at 240°C for 60 seconds to form a 22 nm film. Finally, a photoresist composition was spin-coated on top to form a 100 nm film and soft-baked at 85°C for 60 seconds. The coated wafer was then exposed with an ArF excimer laser (193 nm) through a mask pattern with dense spaces using an ArF exposure device ASML / 1900i (1.35 NA (numerical aperture), annular irradiation, and 0.8o / 0.4iσ (where "o" and "i" are the outer σ and inner σ of the annular irradiation). Thereafter, the wafer was baked at 95°C for 60 seconds, followed by development with a 0.26N tetramethylammonium hydroxide (TMAH) solution and subsequent water washing. The critical dimension (CD) was determined by processing images captured by top-down scanning electron microscopy (SEM) using a Hitachi CG-4000 CD-SEM. An 80 nm trench was obtained using an 80 nm / 160 nm pitch mask. Focus latitude was evaluated by allowing a + / - 10% CD tolerance around the target CD of 80 nm. If the focus latitude was greater than 270 nm, it was designated as A; if the focus latitude was between 200 nm and 270 nm, it was designated as B; and if the focus latitude was less than 200 nm, it was designated as C. Focus latitude was evaluated for the 80 nm trench and the results are summarized in Table 2 below.

[0168] Table 2

[0169] focal length tolerance Example 1 A Example 2 A Example 3 B Example 4 A Example 5 A Comparative Example 1 B Comparative Example 2 C

Claims

1. A photoresist composition comprising: a first polymer formed by free radical polymerization, the first polymer comprising polymerized units formed from monomers comprising an ethylenically unsaturated double bond and an acid-labile group; Photoacid generators; A quencher having formula (1): in: R1 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C 3-20 Cyclic alkyl, said alkyl optionally containing an -O- group in addition to the α-position relative to the amide C(O), or C6-C 20 Aryl; R2 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C3-C 20 Cyclic alkyl, or C6-C 20 Aryl; L is C1-C 20 Straight chain or C3-C 20 a branched alkylene group comprising one or more heteroatom-containing groups independently selected from -O- or -S-, wherein each of R1, R2, and L may independently be substituted or unsubstituted; wherein the quencher does not contain a cross-linkable group; and solvent.

2. The photoresist composition according to claim 1, wherein L includes a plurality of heteroatom-containing groups.

3. The photoresist composition according to claim 1, wherein The one or more heteroatom-containing groups are -O-.

4. The photoresist composition according to claim 1, wherein Each R1 is C1-C 20 Straight chain, C3-C 20 Branched or C3-C 20 Cyclic alkyl groups which contain -O- groups in addition to the α-position relative to the amide C(O).

5. The photoresist composition according to claim 1, wherein The quencher is selected from:

6. The photoresist composition according to claim 1, wherein The first polymer comprises a (meth)acrylate polymer.

7. The photoresist composition of claim 1, further comprising a material containing one or more base-labile groups.

8. The photoresist composition according to claim 1, wherein The first polymer further comprises polymerized units of the following formula: and / or 9. A pattern forming method comprising: (a) applying a layer of the photoresist composition according to claim 1 on a substrate; (b) pattern-wise exposing the photoresist composition layer to activating radiation; as well as (c) developing the exposed photoresist composition layer to provide a resist relief image.

10. The pattern forming method of claim 9, further comprising transferring the pattern of the resist relief image to the substrate.

11. A photoresist composition comprising: a first polymer formed by free radical polymerization, the first polymer comprising polymerized units formed from monomers comprising an ethylenically unsaturated double bond and an acid-labile group; Photoacid generators; A quencher having formula (1): in: R1 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C 3-20 Cyclic alkyl, said alkyl optionally containing an -O- group in addition to the α-position relative to the amide C(O), or C6-C 20 Aryl; R2 is independently a hydrogen atom, C1-C 20 Straight chain, C3-C 20 Branched or C3-C 20 Cyclic alkyl, or C6-C 20 Aryl; wherein L contains multiple heteroatom-containing groups; L is C1-C 20 Straight chain or C3-C 20 A branched alkylene group comprising one or more heteroatom-containing groups independently selected from -O-, -S- or -N(R3)-, wherein R3 is selected from a hydrogen atom or a C1-C 20 Straight chain or C3-C 20 A branched or cyclic alkyl group; each of R1, R2 and L may independently be substituted or unsubstituted; wherein the quencher does not contain a cross-linkable group; and solvent.

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