Sublayers and methods for EUV lithography

Abstract

Novel lithography compositions for use as EUV underlayers are disclosed. The present invention includes methods for fabricating microelectronic structures using these compositions, and structures formed by these methods. The methods include utilizing an underlayer directly beneath a photoresist layer. The underlayer can be coated directly onto a substrate or onto any intermediate layer(s) that can be coated onto a substrate. Preferred underlayers are formed from spin-coatable monomer compositions, oligomer compositions, and / or polymer compositions and exhibit uniform thickness and low roughness. The disclosed methods enable 14 / 28 nm patterns using EUV lithography and allow for better depth of focus (DOF) than standard EUV underlayers.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 445,213, filed on February 13, 2023, entitled "SPIN - ON PRIMER AND METHODS FOR EUV LITHOGRAPHY", which is hereby incorporated by reference in its entirety.

[0002] Technical Field This disclosure relates to materials and methods for manufacturing microelectronic structures using extreme ultraviolet (EUV) lithography.

Background Art

[0003] As the semiconductor industry continues to follow Moore's law, the ever - decreasing requirements for feature sizes necessitate the use of thinner films to prevent pattern collapse. Thinner films require the use of a hard mask to transfer the pattern to the substrate. Extreme ultraviolet (EUV) exposure is expected to be the method selected for single - exposure lithography to achieve the required critical dimension (CD) targets above the 7nm node. Unfortunately, EUV lithography has been hindered by many problems, including a lack of powerful radiation sources, stochastic effects, and adhesion issues.

[0004] Conventional three - layer stacks, including a carbon - containing layer, a silicon - containing underlayer, and a photoresist, often have insufficient adhesion between the photoresist and the silicon underlayer. This insufficient adhesion can lead to significant collapse of the patterned resist, especially at lower critical dimensions.

[0005] One approach was to implement spin-on silicon hard masks, which offer better adhesion to photoresists due to their relatively high carbon content. One significant compromise for improved adhesion is the undesirable substantial reduction in CF4 etching rate as a result of the lower silicon content of the silicon hard mask (Si-HM) layer.

[0006] Alternative stack structures utilizing a "4-layer stack" or a "3-layer stack" have also been proposed. In this structure, a thicker underlayer is coated between the silicon-containing layer (or any intervening layer on the substrate) and the photoresist. [Overview of the project] [Problems that the invention aims to solve]

[0007] This lower layer is intended to act as an adhesion promoter between the two layers and prevent the diffusion of the photoresist component into the lower layer, but conventional layers lacked these features. [Means for solving the problem]

[0008] In one embodiment, the disclosure broadly relates to a method for forming a structure. This method includes forming a lower layer on a stack, forming a photoresist layer on the lower layer, and subjecting at least a portion of the photoresist layer to EUV irradiation. The lower layer is (a) Polymers, oligomers, or mixtures thereof comprising at least about 75 mol% of a monomer having an adhesive portion and a surface-modifying group selected from a silanol portion, a Si-O portion, or both. (b) A monomer compound comprising an adhesive portion and a surface-modifying group selected from a silanol portion, a Si-O portion, or both, or (c) Formed from a composition containing components selected from combinations of (a) and (b).

[0009] In further embodiments, this disclosure may extend to: A substrate having a surface, Optionally, one or more intermediate layers on the substrate surface, and if one or more intermediate layers exist, one or more intermediate layers on the substrate surface that have the uppermost intermediate layer. The layer on the substrate surface, or the layer below the uppermost intermediate layer, and A structure is provided that includes a photoresist on the lower layer. The lower layer is (a) Polymers, oligomers, or mixtures thereof comprising at least about 75 mol% of monomers having an adhesive moiety at the first end of the alkyl group and a Si-O moiety at the second end of the alkyl group, (b) A monomer compound having an adhesive moiety at the first end of the alkyl group and a Si-O moiety at the second end of the alkyl group, or (c) Includes combinations of (a) and (b).

[0010] Further embodiments provide a method for hydrolyzing silanes. This method involves combining silane with an acid and at least one solvent and hydrolyzing the silane for at least 60 minutes. The silanes include glycidylpropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)methyl-dimethoxysilane, 2-chloroethylmethyldimethoxysilane, 3-acetoxypropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-phenylpropylmethyldimethoxysilane, 4-amino-3,3-dimethylbutylmethyldimethoxysilane, vinylmethyldimethoxysilane, and dimeth Selected from 2-dimethoxysilane, phenylmethyldimethoxysilane, glycidylpropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, (methacryloxymethyl)trimethoxysilane, 2-chloroethyltrimethoxysilane, 3-acetoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-phenylpropyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, [(3-triethoxysilyl)propyl]succinic anhydride, or a combination thereof. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram (not to scale) showing one embodiment of a lithography stack. [Figure 2] This shows the uniformity of the material thickness in Example 1. [Figure 3] The line-space focus exposure matrix (FEM) of monomer sublayer 1 in Example 10 is shown. [Figure 4]It is a line-space scanning electron microscope (SEM) photograph (164kX) of the monomer lower layer 1 of Example 10. [Figure 5] It is a Bossung plot of line-space critical dimension versus focus for the monomer lower layer 1 of Example 10. [Figure 6] It is a line-space FEM of the monomer lower layer 2 of Example 11. [Figure 7] It is a graph of critical dimension versus focus for the monomer lower layer 2 of Example 11. [Figure 8] It is a graph of line width roughness versus focus for the monomer lower layer 2 of Example 11. [Figure 9] It is a cross-sectional view of a SEM photograph (164kX) of EUV lithography performed using the monomer lower layer 2 of Example 11. [Figure 10] It is a comparison of CD-dose between the standard EUV lower layer and the monomer lower layer 2 in Example 12. [Figure 11] It is a comparison of CD-DOF between the standard EUV lower layer and the monomer lower layer 2 in Example 12. [Figure 12] It is a comparison of CD-LWR between the standard EUV lower layer and the monomer lower layer 2 in Example 12. [Figure 13] It is a comparison of the process window at the baking temperature that functions best between the standard EUV lower layer and the monomer lower layer 2 in Example 12. [Figure 14(A)] It shows the influence of the baking temperature of the monomer lower layer 2 of Example 12 on CD-dose. [Figure 14(B)] It shows the influence of the baking temperature of the monomer lower layer 2 of Example 12 on CD-DOF. [Figure 14(C)] It shows the influence of the baking temperature of the monomer lower layer 2 of Example 12 on CD-LWR. [Figure 15] It shows the contact hole FEM of the monomer lower layer 2 of Example 12. [Figure 16] It shows the defect review for CD of the monomer lower layer 2 and the standard EUV lower layer of Example 12. [Figure 17] The EUV lithography results for monomer sublayer 2 of Example 12 are shown. [Figure 18] The Bossung plot of the critical dimension versus focus of the monomer sublayer 2 in Example 12 is shown. [Figure 19] The CDU-DOF vs. CD ratio for monomer sublayer 2 and standard spin-on EUV sublayer in Example 12 is shown. [Figure 20] The CDU vs. CD ratio for monomer sublayer 2 and standard spin-on EUV sublayer in Example 12 is shown. [Figure 21] This is the line-space FEM of the material from Example 13 (see Example 21). [Figure 22] This is a top-down SEM image (164kX) of the material from Example 13 (see Example 21). [Figure 23] This is the line-space FEM of the material from Example 13 (see Example 22). [Figure 24] This is a top-down SEM image (164kX) of the material from Example 13 (see Example 22). [Figure 25] This is the line-space FEM of the material from Example 13 (see Example 23). [Figure 26] This is a top-down SEM image (164kX) of the material from Example 13 (see Example 23). [Figure 27] This is the line-space FEM of the material from Example 14 (see Example 24). [Figure 28] This is a top-down SEM image (164kX) of the material from Example 14 (see Example 24). [Figure 29] This is the line-space FEM of the material from Example 14 (see Example 25). [Figure 30] This is a top-down SEM image (164kX) of the material from Example 14 (see Example 25). [Figure 31] This is the line-space FEM of the material from Example 17 (see Example 26). [Figure 32]This is a top-down SEM image (164kX) of the material from Example 17 (see Example 26). [Figure 33] The diagram includes two different lithography stacks, showing the level of metal diffusion from the metal oxide resist to each stack. [Modes for carrying out the invention]

[0012] This disclosure more broadly relates to compositions for forming underlayers (preferably ultrathin underlayers) and methods for forming microelectronic structures using these compositions. The compositions are useful over a wide range of wavelengths but are particularly well suited to EUV lithography processes.

[0013] Composition for lower layer A composition suitable for use as a substrate as described herein comprises a component selected from one or more monomers, oligomers, and / or polymers. Preferred such components include adhesive parenchyma that improve the adhesion of the photoresist layer to the formed substrate and / or "entangle" the substrate with the photoresist layer. Preferred adhesive parenchyma include epoxy groups (including glycidyl groups and / or epoxycyclohexyl groups), isocyanurate groups, benzene groups, carbomethoxy groups, vinyl groups, anhydride groups, carboxylic acids (including dicarboxylic acids), chlorine atoms, or combinations thereof.

[0014] Furthermore, the selected components preferably contain one or more functional groups that can perform surface modification (e.g., enhance surface wettability and / or adhesion) to bond the lower layer to the underlying substrate or any intermediate layer, reduce fouling / lifting, and / or achieve other effects that may be desirable for lithography performance. Suitable examples of such surface modification groups include silanol moieties (e.g., -SiR(OH)2 groups containing two silanol moieties, or -Si(OH)3 groups containing three silanol moieties), Si-O moieties (i.e., [ka] ), or a combination thereof.

[0015] In one or more embodiments, the monomer compound or repeating monomer (in the case of a polymer and / or oligomer component) contains at least two, more preferably at least three, total surface modification groups. Thus, the monomer compound and / or repeating monomer may have at least two or at least three surface modification groups, which are at least one or at least two silanol moieties, at least two or at least three Si-O moieties, or a mixture of silanol moieties and Si-O moieties.

[0016] Regardless of the selected functional group, in some embodiments, the surface-modifying group and the bonding portion are preferably spaced apart from each other within a particular monomer compound or repeating monomer (in the case of polymer and / or oligomeric components). This spacing can be achieved by spacer portions, preferably linear spacer portions. The spacer portion preferably has a first end and a second end substantially opposite the first end, with the surface-modifying group at the first end and the bonding portion at the second end. Examples of suitable spacer portions include alkyl groups (preferably divalent alkyl groups). Preferred alkyl groups are C2 to about C8 alkyl groups, more preferably about C2 to about C5 alkyl groups. The alkyl groups may be substituted or unsubstituted.

[0017] 1. Monomer compounds for use in compositions If the components of the lower layer composition are monomer compounds (i.e., not polymers or oligomers), they can be purchased or synthesized according to the user's preference. In some embodiments, a base or starting monomer containing the adhesive portion and preferably the less reactive silicon-containing groups spaced apart as described above can be hydrolyzed in a weakly acidic solution (e.g., pKa greater than 0) to form a silanol moiety and / or Si-O moiety.

[0018] To hydrolyze the monomer, an acid is added to a suitable hydrolysis solvent(s) in the reactor while stirring. Hydrolysis solvents include propylene glycol monomethyl ether acetate ("PGMEA"), propylene glycol methyl ether ("PGME"), acetone, propylene glycol ethyl ether ("PGEE"), cyclohexanone, ethyl lactate, 3-methyl-1,5-pentanediol, 1,2-propylene glycol, 1,3-propylene glycol, ethylene glycol, or mixtures thereof.

[0019] Suitable acids for hydrolysis include maleic acid, nitric acid, hydrochloric acid, acetic acid, sulfuric acid, or combinations thereof. The acid is typically added at a level of about 0.001 mol% to about 0.1 mol%, preferably about 0.005 mol% to about 0.01 mol%, where mol% is based on the total moles of monomer. The acid / solvent mixture is preferably stirred for about 1 minute to about 20 minutes, more preferably about 5 minutes to about 10 minutes.

[0020] Next, the reactor is filled with the desired monomer(s). The monomer solids percentage in the reaction mixture is generally about 1% to about 15%, preferably about 2% to about 8%, based on 100% by weight of the total weight of the reaction mixture (e.g., monomer, acid, and solvent(s)).

[0021] Preferred starting monomers include alkoxysilanes, particularly dialkoxy and / or trialkoxysilanes. C1-C4 dialkoxysilanes and / or C1-C4 trialkoxysilanes, especially those containing adhesive portions with or without spacer portions as described above, are particularly preferred.

[0022] Examples of such starting monomers include glycidylpropylmethyldiethoxysilane (glyDEOS), 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane (ECHDEOS), phenyltrimethoxysilane (PTMS), (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione) (DAICATEOS), (methacryloxymethyl)methyl-dimethoxysilane, and 2-chloroethylmethyldimethoxy Examples include silanes, 3-acetoxypropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-phenylpropylmethyldimethoxysilane, 4-amino-3,3-dimethylbutylmethyldimethoxysilane, vinylmethyldimethoxysilane (VDMS), dimethyl-dimethoxysilane (MDMS), phenylmethyldimethoxysilane (PDMS), or combinations thereof. In preferred embodiments, the composition is homomonomer, meaning that only one monomer is used.

[0023] After loading the monomers into the reactor, the reaction mixture is stirred typically for about 60 minutes to about 24 hours, preferably about 12 to about 20 hours. The resulting mother liquor can be used "as is" for further formulation.

[0024] Two exemplary hydrolysis reactions are shown in Scheme A. Scheme A [ka]

[0025] 2. Polymers and / or oligomers for use in compositions If the components of the lower layer composition are oligomers (i.e., 2 to 10 monomers or repeating units) or polymers, the polymers or oligomers can be purchased, or the starting monomers can be polymerized or oligomerized according to the user's preference. In some embodiments, the adhesive portion and the base or starting monomer containing less reactive silicon-containing groups, preferably spaced apart as described above, can be simultaneously polymerized and hydrolyzed in a weakly acidic solution (e.g., pKa greater than 0) to form a silanol moiety and / or Si-O moiety.

[0026] In some embodiments, polymers and oligomers are synthesized by loading the starting monomer(s) into an optional distillation apparatus or a reactor with a reflux setting in a suitable polymerization solvent, preferably with stirring. Preferred starting monomers include alkoxysilanes, particularly trialkoxysilanes. C1-C4 trialkoxysilanes, especially those containing adhesive portions with or without spacer portions as described above, are particularly preferred.

[0027] Examples of such starting monomers include glycidylpropyltrimethoxysilane (glyTMS), 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane (ECHTEOS), 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECHTMS), phenyltrimethoxysilane (PTMS), and (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione)(DAICATEOS) Examples include (methacryloxymethyl)trimethoxysilane, 2-chloroethyltrimethoxysilane, 3-acetoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-phenylpropyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, vinyltrimethoxysilane (VTMS), methyltrimethoxysilane (MTMS), [(3-triethoxysilyl)propyl]succinic anhydride (TEOSPSA), or combinations thereof.

[0028] In some embodiments, a mixture of different starting monomers can be used to form a polymer or oligomer.

[0029] In one or more embodiments, at least about 75 mol%, preferably at least about 85 mol%, and more preferably at least about 95 mol%, of the polymer or oligomer comprises the above monomers. In one embodiment, the polymer and / or oligomer is essentially made from, or even made from, one or more of the above monomer types.

[0030] In some embodiments, the polymer is a homopolymer and / or the oligomer is a homooligomer. In other words, the polymer and / or oligomer are essentially composed of, or even derived from, a single type of monomer of the above monomer types.

[0031] Polymerization solvents include PGMEA, PGME, acetone, PGEE, cyclohexanone, ethyl lactate, 3-methyl-1,5-pentanediol, 1,2-propylene glycol, 1,3-propylene glycol, ethylene glycol, or mixtures thereof. The monomer solids percentage in the reaction mixture is typically about 1% to about 25%, preferably about 5% to about 20%, based on 100% by weight of the total weight of the reaction mixture (e.g., monomers, catalyst, and solvent(s)).

[0032] In some embodiments, the catalyst is then slowly packed into the reactor at a temperature of about 20°C to about 30°C, preferably about 25°C, for about 5 minutes to about 60 minutes, preferably about 10 minutes to about 30 minutes. The reactants are typically hydrolyzed for about 5 minutes to about 60 minutes, preferably about 15 minutes to about 45 minutes.

[0033] Suitable polymerization catalysts include nitric acid, hydrochloric acid, acetic acid, trifluoroacetic acid, sulfonic acid, or combinations thereof. The catalyst is preferably added as an aqueous solution. The catalyst solution is preferably prepared in water as a solution of about 0.001 N to about 10 N, more preferably a solution of about 0.01 N to about 5 N, even more preferably a solution of about 3 N for weak acids (i.e., pKa greater than 0), and about 0.01 N for strong acids (i.e., pKa less than or equal to about 0). These aqueous catalyst solutions are preferably added in amounts of about 0.5 equivalents to about 20 equivalents, more preferably about 5 equivalents to about 15 equivalents, and even more preferably about 10 equivalents relative to the total monomer, where 1 equivalent is approximately equal to 1 mole of water per mole of monomer (or about 18 grams of water per mole of monomer).

[0034] The reactants are further stirred at a temperature of preferably about 20°C to about 100°C, more preferably about 40°C to about 100°C, for about 60 minutes to about 24 hours, preferably about 6 hours to about 16 hours. The reaction may optionally be carried out under an inert atmosphere such as nitrogen.

[0035] The crosslinkability of the lower layers can be enhanced by polymerizing the material under conditions that promote more branched polymer structures rather than more linear polymer structures during the synthesis of the polymer material. While many variables affect the polymer structure, more branched and higher crosslinked polymers can be synthesized by using a lower acid concentration, increasing the amount of water, increasing the hydrolysis time, and / or decreasing the reaction time and temperature. These and other process conditions can be controlled to produce a higher proportion of low-weight oligomers during synthesis, thus promoting more branching in the polymer structure and resulting in more crosslinking sites.

[0036] Preferred oligomers and polymers preferably have a relatively low weight-average molecular weight, i.e., when determined by gel permeation chromatography (GPC) using a linear polystyrene standard, preferably less than about 2,500 daltons, more preferably less than about 2,000 daltons, even more preferably between about 300 and 2,000 daltons, and most preferably between about 800 and 1,500 daltons. Furthermore, preferred oligomers and polymers preferably have a relatively low polydispersity, i.e., preferably less than about 2, more preferably less than about 1.5, and even more preferably less than about 1.3.

[0037] In one or more embodiments, if the starting monomer contains 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane as the sole monomer or as one of two or more monomer types, the polymer preferably has a weight-average molecular weight of less than about 2,000 daltons and / or is a branched polymer.

[0038] In some embodiments, it is also preferable that the polymer or oligomer skeleton does not contain metal atoms. In one or more embodiments, the polymer or oligomer contains less than about 5% metal, preferably less than about 3% metal, more preferably less than about 1% metal, and even more preferably about 0% metal, based on 100% by weight of the total weight of the polymer or oligomer.

[0039] 2. Preparation of the composition The reaction mixture (mother liquor) may be formulated without further treatment, or the components (i.e., monomer compounds, polymers, oligomers) may be isolated before being used in the final formulation. In the latter case, the components are dispersed or dissolved in a solvent system (i.e., one or more solvents). Preferred solvent systems include solvents selected from PGMEA, PGME, PGEE, propylene glycol n-propyl ether ("PnP"), ethyl lactate, cyclohexanone, gamma-butyrolactone ("GBL"), methyl isobutylcarbinol, 3-methyl-1,5-pentanediol, 1,2-propylene glycol, 1,3-propylene glycol, ethylene glycol, or mixtures thereof.

[0040] The solvent system is preferably used at a level of about 20% to about 99.99% by weight, more preferably about 80% to 99.9%, and even more preferably about 90% to about 99.9%, based on 100% by weight of the total weight of the composition. The composition used to form the lower layer preferably contains a solids content of about 0.01% to about 20% by weight, more preferably about 0.01% to about 10% by weight, and even more preferably about 0.05% to about 1.5% by weight, based on 100% by weight of the total weight of the composition.

[0041] The components are preferably present at a level of about 0.01% to about 1% by weight, more preferably about 0.01% to about 0.5% by weight, and even more preferably about 0.01% to about 0.1% by weight, based on 100% by weight of the total weight of the composition. Additionally or alternatively, the components are preferably present at a level of about 50% to about 100% by weight, more preferably about 98% to about 100% by weight, based on 100% by weight of the total weight of all solids present in the composition.

[0042] In some embodiments, catalysts such as crosslinking catalysts can be included in the underlying composition. Suitable catalysts include those selected from thermal acid generators (TAGs, e.g., quaternary ammonium sequestered triflic acid thermal acid generators, e.g., TAG2689 and TAG2690 from King Industries), acids (such as nitric acid or maleic acid), benzyltriethylammonium chloride ("BTEAC"), ethyltriphenylphosphonium bromide, tetrabutylphosphonium bromide, or combinations thereof. When used, the catalyst is present in a particular composition at a level of preferably about 0.01% to about 10% by weight, more preferably about 0.1% to about 5% by weight, with the total weight of the components being 100% by weight.

[0043] In some embodiments, surfactants may be included in the composition to improve coating quality. Nonionic surfactants, such as those having a highly fluorinated alkyl group, are preferred. Examples of commercially available preferred surfactants include R30N (DIC Corporation, Japan) and FS3100 (The Chemours Company FC, LLC, USA). The surfactant is present in a particular composition at a level of preferably about 0.01% to about 10% by weight, more preferably about 0.1% to about 5% by weight, based on 100% by weight of the total weight of the components.

[0044] By mixing the above components together in a solvent system, a composition is formed that can be used to form the underlying layers described below. Furthermore, any optional component (e.g., a surfactant) is also dispersed in the solvent system (e.g., simultaneously). Examples of potential optional components include those selected from bases, base catalysts, polymers (other than or in addition to those described above), or mixtures thereof.

[0045] In some embodiments, the composition essentially consists of, or even consists of, components dissolved or dispersed in a solvent system.

[0046] In other embodiments, the composition essentially consists of, or even consists of, components and catalysts dissolved or dispersed in a solvent system.

[0047] In one embodiment, the composition essentially consists of, or even consists of, components and surfactants dissolved or dispersed in a solvent system.

[0048] In yet another embodiment, the composition essentially consists of, or even consists of, components, catalysts, and surfactants dissolved or dispersed in a solvent system.

[0049] In preferred embodiments, the composition used to form the lower layer is essentially metal-free. That is, the metal content of the composition is less than about 0.005% by weight, preferably less than about 0.001% by weight, and more preferably about 0% by weight, with the total weight of solids in the composition being 100% by weight.

[0050] In one or more embodiments, the composition used to form the lower layer is essentially free of chromophores that are part of the structural components, and also free of chromophores that are separately added to the composition. That is, the total chromophore content of the composition (including any further separately added as part of the components) is less than about 0.005% by weight, preferably less than about 0.001% by weight, and more preferably about 0% by weight, with the total weight of solids in the composition being 100% by weight. In some embodiments, the composition used to form the lower layer essentially does not contain chromophores that are separately added to the composition (i.e., chromophores that are not part of the structure of the components). In these embodiments, the “added” chromophore content of the composition is less than about 0.005% by weight, preferably less than about 0.001% by weight, and more preferably about 0% by weight, with respect to 100% by weight of the total weight of solids in the composition.

[0051] Method of using a silicone hard mask composition Referring to Figure 1(A), the stack 10 is schematically shown. The stack 10 includes a substrate 12 having a surface 14 and an optional intermediate layer(s) 16.

[0052] The substrate 12 includes a microelectronic substrate, preferably a semiconductor substrate. Exemplary substrates 12 include silicon, SiGe, SiO2, Si3N4, SiON, SiCO:H (e.g., sold by SVM under the name Black Diamond, Santa Clara, California, USA), tetramethyl silate and tetramethyl-cyclotetrasiloxane combinations (e.g., sold under the name CORAL), aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, tantalum nitride, Ti3N4, hafnium, HfO2, ruthenium, indium phosphide, glass, or combinations thereof. The surface 14 of the substrate 12 may be planar or may include topographic features (e.g., via holes, trenches, contact holes, raised features, lines, etc.). As used herein, “topography” refers to the height or depth of structures within or on the substrate surface 14. In Figure 1(A), surface 14 is shown as having substantially planar topography, but the topography may include non-planar topography, such as lines, trenches, holes, pillars, etc.

[0053] Figure 1 shows a single intermediate layer 16 for illustrative purposes, but the stack 10 may include multiple intermediate layers or may not include any intermediate layers at all. In some embodiments, a suitable intermediate layer 16 may include a primer layer, which may include a separate, isolated layer or a layer more appropriately characterized as a modifying layer on the substrate surface 14. Preferred primers include hexamethyldisilizanes ("HMDS"). The primer can be formed, for example, by exposing the substrate 12 to vapor of the primer composition in a sealed chamber while heating at about 150°C for about 90 seconds.

[0054] Another suitable intermediate layer 16 includes a carbon-rich layer that can be formed on the substrate surface 14 or on any other intermediate layer that may be present (e.g., a prime layer or modified surface as discussed above). The carbon-rich layer includes a spin-on carbon (SOC) layer, an amorphous carbon layer, and a carbon planarization layer. An exemplary carbon-rich layer is generally formed from a carbon-rich composition comprising a polymer dissolved or dispersed in a solvent(s) and one or more optional components, including an acid quencher, a base quencher, a catalyst, a crosslinking agent, a surface modification additive, or a mixture thereof. A preferred carbon-rich composition can be formed into a relatively thick layer and therefore typically has a solids content of about 0.1% to about 70% by weight, more preferably about 5% to about 40% by weight, and even more preferably about 10% to about 30% by weight, with the total weight of the carbon-rich composition being 100% by weight. The term "carbon-rich" refers to a composition and / or layer containing more than about 50% by weight of carbon, preferably more than about 70% by weight of carbon, more preferably about 75% to about 95% by weight of carbon, and even more preferably about 75% to about 80% by weight of carbon, with the total solids content in the composition being 100% by weight.

[0055] The carbon-rich layer can be formed by any known coating method, one preferred method being spin-coating at a speed of about 1,000 to about 5,000 rpm, preferably about 1,250 to about 1,750 rpm, for a time of about 30 to about 120 seconds, preferably about 45 to about 75 seconds. After coating the carbon-rich composition, it is preferable to heat the mixture to a temperature of about 100°C to about 400°C, more preferably about 160°C to about 350°C, for about 30 to about 120 seconds, preferably about 45 to about 60 seconds, to evaporate the solvent. The average thickness of the carbon-rich layer after baking is typically about 10 nm to about 120 nm, preferably about 20 nm to about 100 nm, more preferably about 40 nm to about 60 nm, and even more preferably about 50 nm to about 60 nm. As used herein, “average thickness” is determined by using an ellipsometer and taking the average of five measurements at five different positions. The carbon-rich layer may also be formed by other conventional coating methods, including chemical vapor deposition ("CVD"), plasma-enhanced chemical vapor deposition ("PECVD"), atomic layer deposition ("ALD"), or plasma-enhanced atomic layer deposition ("PEALD").

[0056] An optional hard mask layer can be applied to the substrate surface 14 adjacent to the carbon-rich material, or to any intermediate layer on the substrate surface 14. The hard mask layer can be formed by any known coating method, such as chemical vapor deposition (CVD) or plasma-enhanced chemical vapor deposition (PECVD). Another preferred method is spin coating at a speed of about 1,000 to about 5,000 rpm, preferably about 1,250 to about 1,750 rpm, for a time of about 30 to about 120 seconds, preferably about 45 to about 75 seconds.

[0057] A suitable hard mask layer is preferably a high-silicon-containing material selected from the group consisting of silanes, siloxanes, silsesquioxanes, silicon oxynitride, silicon nitride, polysilicon, amorphous silicon, or mixtures thereof, or any layer having a high etching bias to the underlying layer. A suitable hard mask layer generally comprises a polymer dissolved or dispersed in a solvent system together with one or more of the following components: a surfactant, an acid or base catalyst, and a crosslinking agent.

[0058] A preferred composition for forming a hard mask layer has a solid content of preferably about 0.1% to about 70%, more preferably about 0.5% to about 10%, even more preferably about 0.5% to about 2%, and most preferably about 0.5% to about 1%, based on 100% by weight of the total weight of the hard mask composition. After applying the hard mask, it is preferable to evaporate the solvent by heating at a temperature of about 100°C to about 300°C, more preferably about 150°C to about 250°C, for about 30 seconds to about 120 seconds, preferably about 45 seconds to about 60 seconds. The average thickness of the hard mask layer after baking is preferably about 5 nm to about 50,000 nm, more preferably about 5 nm to about 1,000 nm, and even more preferably about 10 nm to about 30 nm. The hard mask layer preferably has an etching rate of about 0.75 times or more the etching rate of the photoresist in a fluorine-rich plasma atmosphere. Additionally or alternatively, the etching rate of the hard mask layer is preferably about 20% or less (5 times slower) than the etching rate of the carbon-rich layer in the acid-rich plasma etching atmosphere.

[0059] Commercially available hard mask layers can be used, and some preferred hard mask layers include copolymers of monomers selected from the group including phenethyltrimethoxysilane (PETMS), 2-(carbomethoxy)ethyltrimethoxysilane (CMETMS), tetraethoxysilane (TEOS), methyltrimethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane (MTMS), ethyltrimethoxysilane (ETMS), (3-glycidioxypropyl)triethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECHTMS).

[0060] A particularly preferred silicon hard mask has a low carbon content, preferably less than about 30% by weight of carbon, more preferably less than about 25% by weight of carbon, and even more preferably less than about 20% by weight of carbon. A silicon hard mask also preferably has a high silicon content, preferably at least about 25% by weight of silicon, more preferably at least about 30% by weight of silicon, and even more preferably at least about 40% by weight of silicon.

[0061] The lower layer 18 can be formed using the aforementioned lower layer compositions, regardless of whether the stack 10 contains zero, one, two, or more intermediate layers (Figure 1(B)). The lower layer 18 can be formed directly on the substrate surface 14 if no intermediate layers are used (not shown), on the intermediate layer 16 if only one intermediate layer is used (as in Figure 1B), or, in embodiments containing multiple intermediate layers, on the intermediate layer furthest from the substrate surface 14 (i.e., the topmost intermediate layer, preferably the hard mask layer) (not shown).

[0062] One preferred coating method involves spin-coating the underlying composition at a speed of about 350 rpm to about 4,000 rpm, preferably about 1,000 rpm to about 2,000 rpm, for a time of about 20 seconds to about 60 seconds, preferably about 30 seconds to about 60 seconds. After coating the underlying composition to form the underlying layer 18, the underlying layer 18 is preferably heated to a temperature high enough to evaporate substantially all (about 95% or more), preferably all (about 100%) of the solvent present in the underlying layer 18, resulting in crosslinking of polymers or oligomers in the underlying composition in some embodiments. If monomer compounds are included in the underlying composition, preferred baking conditions are a temperature of preferably about 120°C to about 205°C, more preferably about 150°C to about 180°C, and a baking time of about 20 seconds to about 60 seconds, preferably about 30 seconds to about 60 seconds. When polymers and / or oligomers are included in the underlying composition, preferred baking conditions are a temperature of preferably about 120°C to about 250°C, more preferably about 170°C to about 230°C, and a baking time of about 20 seconds to about 60 seconds, preferably about 30 seconds to about 60 seconds.

[0063] Scheme B shows the chemical reactions and / or interactions that occur during spin coating and baking, and the component in the underlying composition used to form the underlying layer 18 is hydrolyzed glycidylpropyl methyldimethoxysilane (glyDMS), the preparation of which is schematically shown in Scheme A above. Scheme B [ka]

[0064] In scheme B, the adhesive portion contains epoxy groups (specifically glycidyl groups), and the surface modification group contains a silanol moiety. The selected surface modification group interacts with chemical groups on the surface of the substrate or top intermediate layer during spin coating and baking (molecular interactions and / or chemical reactions, e.g., covalent reactions). This positions the lower layer components such that the surface modification groups are generally oriented toward the substrate or top intermediate layer, and the adhesive portion is generally oriented toward the photoresist layer that is ultimately coated on the lower layer (as described below).

[0065] Scheme B illustrates this chemical property with respect to a component that is a monomer compound (i.e., hydrolyzed glycidylpropylmethyldimethoxysilane), but it will be understood that similar interactions occur regardless of the selected component. Furthermore, if the component or oligomer is a polymer and / or oligomer, crosslinks may exist between monomers on the same polymer or oligomer molecule and / or between different polymer or oligomer molecules.

[0066] The average thickness of the baked underlayer 18 is less than about 4.5 nm, preferably less than about 3 nm, more preferably about 0.5 nm to 3 nm, even more preferably about 0.5 nm to about 2 nm, and most preferably about 0.5 nm to about 1 nm. In one preferred embodiment, the underlayer 18 is a single layer. If the surface to which the underlayer 18 is applied includes topography, it is preferable that the underlayer 18 is applied to a thickness sufficient to substantially cover the topography. In one embodiment, the underlayer 18 conforms to any topography on the surface to which the underlayer 18 is applied.

[0067] In some embodiments, the lower layer 18 has a low metal content. That is, the metal content is less than about 0.005% by weight, preferably less than about 0.001% by weight, and more preferably about 0% by weight, with the total weight of the lower layer 18 being 100% by weight. It is also preferable that the lower layer 18 is non-conductive.

[0068] It will be understood that the desired contact angle when a water droplet is placed on the lower layer 18 depends on the application. The surface contact angle of the lower layer 18 can be determined by using water as the droplet solvent and averaging five measurements obtained at different spots using the VCA-3000S wafer system (AST Products, Billerica, Massachusetts) contact angle measuring tool. In some embodiments, the contact angle of the lower layer 18 after baking is preferably about 50° to about 65°, more preferably about 55° to about 59°.

[0069] The lower layer 18 is preferably substantially undevelopable (i.e., substantially insoluble) using typical organic solvents such as ethyl lactate, propylene glycol methyl ether acetate, propylene glycol methyl ether, propylene glycol n-propyl ether, cyclohexanone, acetone, gamma butyrolactone, or mixtures thereof. Therefore, when subjected to a peel test, the lower layer 18 preferably has a peel percentage of less than about 25%, more preferably less than about 10%, even more preferably less than about 1%, and even more preferably about 0%. The peel percentage can be determined by measuring the average contact angle and average thickness of the lower layer 18 (determined by averaging measurements obtained at five different positions, respectively) before the lower layer 18 is exposed to any developer solvent. These averaged measurements are the initial film contact angle and initial film thickness. Next, the solvent (e.g., ethyl lactate) is paddled onto the film for about 30 seconds, and then the solvent is peeled off by spin-drying at about 3,000 rpm for about 30 seconds. The average contact angle and average thickness were again determined by measuring at five locations on the wafer that were approximately the same locations used to determine the initial film contact angle and initial film thickness, respectively. The average of these measurements represents the final film contact angle and final film thickness, respectively.

[0070] The amount of peeling is the difference between the initial film thickness and the final film thickness. The peeling percentage is as follows: Peeling % = (Amount of peeling / Initial average film thickness) × 100

[0071] In some cases, the lower layer 18 may be so thin that the thickness measurement cannot indicate the delamination percentage. In these cases, the contact angle may be a more accurate indicator of delamination. In these cases, the same test method as described above for thickness is used, except for measuring the change in contact angle. In these cases, the change in contact angle after delamination is preferably within about 3°, more preferably within about 2°, and even more preferably within about 1°.

[0072] In some embodiments, the lower layer 18 is crosslinked. For example, the lower layer 18 is preferably sufficiently crosslinked such that the peeling percentage is less than about 30%, more preferably less than about 20%, and even more preferably less than about 10%. The advantage of the crosslinking of the lower layer 18 is that there is little to no unbound polymer in the lower layer 18 after baking. This minimal or absent unbound polymer is likely to eliminate the need to peel off unbound polymer during the semiconductor device manufacturing process, thereby reducing the number of steps and improving throughput. In one embodiment, there is no solvent or developer rinsing step required before coating the photoresist.

[0073] In addition to the peel test, there is further indication of the high degree of crosslinking of the lower layer 18. Preferably, there is substantially no change in the water contact angle after contact with the solvent or developer; i.e., the change in the contact angle is preferably less than about 5°, more preferably less than about 3°.

[0074] Another indicator of sufficient crosslinking is good thickness uniformity and a substantially uniform, defect-free surface as measured by KLA SP5. Preferably, the sublayer 18 has sublimation of less than about 200 ng, more preferably less than about 100 ng, and even more preferably less than about 50 ng, as measured by quartz crystal microbalance (QCM) when heated to about 205°C for about 3 minutes. A well-crosslinked sublayer 18 generally has a surface roughness (R1) of less than about 0.15, more preferably less than about 0.125, and even more preferably less than about 0.10, as measured by atomic force microscopy.

[0075] In one or more embodiments, if the component is a polymer containing 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane monomer as the sole monomer or one of two or more monomer types, the lower layer 18 is preferably crosslinked and / or exhibits less than about 30% exfoliation, more preferably less than about 20%, even more preferably less than about 10%, and most preferably less than about 2%.

[0076] After the lower layer 18 is formed, a photoresist layer 20 (i.e., an image-forming layer) having an upper surface 21 is formed on the lower layer 18. A preferred photoresist layer 20 is an EUV photoresist, and any commercially available EUV photoresist composition can be used to form the photoresist layer 20. In one embodiment, the photoresist layer 20 is a chemically amplified resist (CAR). In another embodiment, the photoresist layer 20 is a non-chemically amplified resist. In one embodiment, the non-chemically amplified photoresist includes metals selected from the group consisting of titanium, zinc, tin, hafnium, zirconium, indium, vanadium, cobalt, molybdenum, tungsten, aluminum, gallium, silicon, germanium, phosphorus, arsenic, yttrium, lanthanum, cerium, lutetium, and mixtures thereof. In another embodiment, the photoresist layer 20 includes a metal oxide or organometallic compound in the photoresist composition.

[0077] In some embodiments, the photoresist layer 20 is substantially metal-free. That is, the metal content of the photoresist 20 is less than about 0.005% by weight, preferably less than about 0.001% by weight, and more preferably about 0% by weight, based on 100% by weight of the total weight of the photoresist layer 20.

[0078] Suitable EUV photoresists are available from several commercial suppliers, including JSR, TOK, Sumitomo, Shin Etsu, FujiFilm, Inpria, Irresistible Materials, and Zeon.

[0079] Regardless of the type of photoresist, the photoresist layer 20 can be formed by any conventional method, one preferred method being to spin-coat the photoresist composition at a speed of about 350 rpm to about 4,000 rpm (preferably about 1,000 rpm to about 2,500 rpm) for a period of about 10 seconds to about 60 seconds (preferably about 10 seconds to about 30 seconds). The photoresist layer 20 is then optionally post-bake ("PAB") at a temperature of at least about 45°C, preferably about 80°C to about 250°C, more preferably about 100°C to about 150°C for about 20 seconds to about 30 minutes, more preferably about 30 seconds to about 20 minutes. The average thickness of the photoresist layer 20 after baking is typically about 5 nm to about 200 nm, preferably about 10 nm to about 50 nm, more preferably about 20 nm to about 40 nm.

[0080] One advantage of using the underlayer 18 described herein is that, when used in combination with metal oxide resists (MORs), such as some tin oxide resists developed for EUV applications, the underlayer 18 can reduce metal diffusion from the resist into the stack far more effectively than other options. This is important for minimizing or preventing contamination of the substrate 12, the intermediate layer 16, and / or the fabricated microelectronic device by metal in the MOR. The underlayer 18 reduces metal (e.g., Sn) contamination in any intermediate layer 16 and / or substrate 12 by at least about 50%, more preferably at least about 75%, compared to the same structure without the underlayer 18. Furthermore, the underlayer 18 can prevent cross-mixing between the EUV photoresist layer 20 and any intermediate layer 16 beneath the underlayer 18.

[0081] Referring to Figure 1(C), a mask 22 is positioned above the upper surface 21 of the photoresist layer 20. The mask 22 has an exposure portion 24 designed to allow radiation (in the case of EUV) to be reflected by the mask and come into contact with the surface 21 of the photoresist layer 20, thus forming an exposure region 26 on and / or within the photoresist layer 20. The mask 22 also includes a non-exposure portion 28 designed to absorb or block radiation to prevent radiation from coming into contact with the surface 21 of the photoresist layer 20 in specific areas (i.e., non-exposure region 30), thus resulting in selective exposure of the photoresist layer 20. It will be readily apparent to those skilled in the art that the type of mask and the arrangement of the reflective and absorbing portions (i.e., the exposure portion 24 and the non-exposure portion 28) are designed based on the desired pattern formed on the photoresist layer 20, ultimately the underlayer 18, any intermediate layer 16, and the substrate 12.

[0082] The exposure wavelength is preferably about 10 nm to about 400 nm, more preferably about 13 nm to about 193 nm. In one embodiment, the layer is exposed to wavelengths less than about 20 nm, preferably about 11 nm to about 14 nm, more preferably about 13.5 nm, including EUV radiation. Nevertheless, a preferred exposure dose is about 5 mJ / cm². 2 ~Approx. 100mJ / cm 2 Preferably about 10 mJ / cm² 2 ~about 80mJ / cm 2 More preferably about 20 mJ / cm² 2 ~about 60mJ / cm 2 That is the case.

[0083] After exposure, the photoresist layer 20 is optionally subjected to post-exposure baking (PEB) at a temperature of at least about 45°C, preferably about 60°C to about 250°C, more preferably about 80°C to about 150°C, for about 20 seconds to about 5 minutes, preferably about 30 seconds to about 2 minutes.

[0084] Next, the photoresist layer 20 is brought into contact with a developer to form a pattern 32 on the photoresist layer 20' (Figure 1(D)). Depending on whether the photoresist used is positive or negative, the developer either peels off the exposed portion of the photoresist layer 20' or peels off the unexposed portion of the photoresist layer 20' to form the pattern. The pattern 32 is then transferred to the underlying layer 18, any existing intermediate layer 16 (e.g., a hard mask layer), and finally to the substrate 12. This pattern transfer can be performed via plasma etching (e.g., CF4 etching solution, O2 etching solution), wet etching, or a development process. In embodiments where the pattern is transferred from the photoresist layer 20' to the substrate 12 by etching, the etching rate of the underlying layer 18 relative to the EUV photoresist used (e.g., CAR photoresist, non-CAR photoresist, or organometallic photoresist) is preferably at least about 1x, and more preferably about 1.5x to about 2x.

[0085] Regardless of whether the pattern transfer is performed by etching or development, the resulting features can have high resolution. For example, a resolution of less than approximately 40 nm, preferably less than 30 nm, can be achieved with the method of the present invention. Advantageously, the underlying layer of the present invention also improves the tilt margin of the final feature. The tilt margin is the dose-to-size ratio and the dose range from the dose at which the structure is stationary.

[0086] Further advantages of various embodiments will be apparent to those skilled in the art upon further examination of the disclosures herein and the following embodiments. It will be understood that the various embodiments described herein are not necessarily mutually exclusive unless otherwise indicated herein. For example, features described or illustrated in one embodiment may, but may not, be included in other embodiments. Thus, this disclosure encompasses various combinations and / or incorporations of the specific embodiments described herein.

[0087] As used herein, when the phrase "and / or" is used in a list of two or more items, it means that any one of the listed items may be used alone, or any combination of two or more of the listed items may be used. For example, if it is stated that a composition contains or excludes components A, B and / or C, the composition may contain or exclude A alone, B alone, C alone, a combination of A and B, a combination of A and C, a combination of B and C, or a combination of A, B and C.

[0088] This specification also uses numerical ranges to quantify certain parameters relating to various embodiments. Where numerical ranges are provided, it should be understood that such ranges should be interpreted as providing literal support for limitation of claims that enumerate only the lower limits of the range and limitation of claims that enumerate only the upper limits of the range. For example, a disclosed numerical range of about 10 to about 100 provides literal support for claims that state “greater than about 10” (no upper limit) and claims that state “less than about 100” (no lower limit). [Examples]

[0089] The following examples illustrate the methods according to the present disclosure. However, it should be understood that these examples are provided for illustrative purposes only, and nothing in them should be construed as limiting the entire scope.

[0090] [Example 1] Synthesis and formulation of monomer lower layer 1 In this example, 1.8 grams of water and 35.0 grams of self-filtered PGME (Fuji Film Ultra Pure Solutions, Castroville, California) were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.87 grams of 0.2 wt% maleic acid (diluted from 2 wt% maleic acid in PGME, manufactured by Sigma-Aldrich, St. Louis, Missouri) were added to the filtered PGME solution. Next, 2.5 grams of glycidylpropyl methyldimethoxysilane (glyDMS, Gelest, Morrisville, Pennsylvania) were added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0091] The resulting mother liquor, containing 5% solids in PGME, was diluted to 1% solids by mixing 20 grams of it with 70.1 grams of in-house filtered PGME and 9.9 grams of in-house filtered PGMEA (Fuji Film Ultra Pure Solutions, Castroville, California) (90:10 mixture).

[0092] [Example 2] Synthesis and formulation of monomer lower layer 2 In this example, 1.8 grams of water and 35.0 grams of filtered PGME were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.88 grams of 0.2% maleic acid were added to the PGME solution. Next, 2.58 grams of 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane (ECHDEOS, Gelest, Morrisvir) were added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0093] The resulting mother liquor was diluted to a 1% solid content in PGME / PGMEA by mixing 20 grams of mother liquor with 70.1 grams of filtered PGME and 9.9 grams of filtered PGMEA (90:10 mixture).

[0094] [Example 3] Synthesis and formulation of monomer lower layer 3 In this example, 1.8 grams of water and 26.0 grams of filtered PGME were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.65 grams of 0.2% maleic acid were added to the PGME solution. Next, 2.58 grams of phenylmethyldimethoxysilane (PDMS, Gelest, Morrisvir) were added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0095] The resulting mother liquor was diluted to a 1% solid content in PGME / PGMEA by mixing 20 grams of mother liquor with 70.1 grams of filtered PGME and 9.9 grams of filtered PGMEA (90:10 mixture).

[0096] [Example 4] Synthesis and formulation of monomer lower layer 4 In this example, 1.8 grams of water and 24.57 grams of filtered PGME were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.61 grams of 0.2% maleic acid was added to the PGME solution. Next, 1.98 grams of phenyltrimethoxysilane (PTMS, Gelest, Morrisvir) was added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0097] The resulting mother liquor was diluted to a 1% solid content in PGME / PGMEA by mixing 20 grams of mother liquor with 70.1 grams of filtered PGME and 9.9 grams of filtered PGMEA (90:10 mixture).

[0098] [Example 5] Synthesis and formulation of monomer lower layer 5 In this example, 1.8 grams of water and 3.89 grams of filtered PGME were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.85 grams of 0.2% maleic acid were added to the PGME solution. Next, 2.24 grams of 3-phenylpropylmethyldimethoxysilane (Gelest, Morrisville, Pennsylvania) were added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0099] The resulting mother liquor was diluted to a 1% solid content in PGME / PGMEA by mixing 20 grams of mother liquor with 70.1 grams of filtered PGME and 9.9 grams of filtered PGMEA (90:10 mixture).

[0100] [Example 6] Synthesis and formulation of monomer lower layer 6 In this example, 1.8 grams of water and 3.31 grams of filtered PGME were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.58 grams of 0.2% maleic acid were added to the PGME solution. Next, 1.69 grams of 2-chloroethylmethyldimethoxysilane (ClDMS, Gelest, Morrisvir) was added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0101] The resulting mother liquor was diluted to a 1% solid content in PGME / PGMEA by mixing 20 grams of mother liquor with 70.1 grams of filtered PGME and 9.9 grams of filtered PGMEA (90:10 mixture).

[0102] [Example 7] Synthesis and formulation of monomer lower layer 7 In this example, 3.6 grams of water and 28.12 grams of filtered PGME were weighed into a 100 mL Aicello bottle and stirred for 5 minutes using a magnetic stirrer. While stirring, 0.70 grams of 0.2% maleic acid were added to the PGME solution. Next, 2.96 grams of dimethoxydimethylsilane (MDMS, Gelest, Morrisvir) were added and stirred for a further 5 minutes. The solution was then stirred at room temperature for a further 16 hours.

[0103] The resulting mother liquor was diluted to a 1% solid content in PGME / PGMEA by mixing 20 grams of mother liquor with 70.1 grams of filtered PGME and 9.9 grams of filtered PGMEA (90:10 mixture).

[0104] [Example 8] Test of monomer lower layer 1 The formulation prepared in Example 1 was spin-coated onto a silicon wafer at 300 rpm for 3,000 seconds and baked at 180°C for 60 seconds. After baking, a layer approximately 10 Å thick was formed on the surface of the silicon wafer. Coating quality was inspected using a laser confocal microscope, uniformity was evaluated by ellipsometry, and surface roughness was measured using an atomic force microscope. Figure 3 shows the thickness uniformity measurement. The average thickness was 13.24 Å, and the standard deviation was 1.321 Å.

[0105] [Example 9] Testing of monomer underlayer materials The formulations prepared in Examples 1-7 were spin-coated onto a 100 mm silicon wafer at 1500 rpm for 60 seconds and baked at 180°C for 60 seconds. The stability of the underlying layer was evaluated using a solvent peel test, in which PGME was paddled onto the underlying layer for 30 seconds, followed by spin-drying at 1500 rpm. The thickness of the underlying layer before and after peeling was measured using an M-2000 ellipsometer (JAWoollam, Lincoln, Nebraska).

[0106] The surface energy of the lower layer was measured using the AST optima (B5RM5208-143) contact angle measuring tool.

[0107] The molecular weight of each formulation was measured using gel permeation chromatography (GPC). More specifically, GPC was performed using a column set consisting of a Phenogel 7.8 × 300 mm single-pore column, 1 × 500 angstrom, 1 × 100 angstrom, 2 × 50 angstrom columns, and a guard column. The column oven was set to 40°C. A THF (tetrahydrofuran) mobile phase was used at a flow rate of 1 mL / min. A differential refractometer was used for detection. Standard polystyrene Agilent PS-L vials were used. For the preparation of formulation samples for GPC analysis, the samples were diluted to a 0.5% solid content in the mobile phase, and then each sample was injected at a volume of 50 μL and run for 45 minutes. The results for each formulation sample are shown in Table 1. Table 1. Molecular weight, thickness, and contact angle of the underlying material. [Table 1]

[0108] [Example 10] Lithography of monomer sublayer 1 The formulation prepared in Example 1 was spin-coated as an underlayer on a pre-baked silicon wafer at 1,350 rpm for 60 seconds and baked at 180°C for 60 seconds. Then, the TOK Penta resist was spin-coated on the wafer with the underlayer coating at 1,500 rpm for 60 seconds and baked at 110°C for 60 seconds. EUV lithography was performed at IMEC using the NXE3400 scanner system. Figure 4 shows EUV lithography focus exposure matrix (FEM) and scanning electron microscope (SEM) images at central dose / central focus. Figure 5 shows the Bossong plot for CD versus focus.

[0109] [Example 11] Lithography of monomer sublayer 1 The formulation prepared in Example 2 was spin-coated onto a 100 mm unused silicon wafer pre-baked at 400°C at 1350 rpm for 60 seconds, and then baked at 180°C for 60 seconds to form a uniform underlayer with a thickness of less than 1 nanometer and low surface roughness. Next, the TOK Penta resist was spin-coated onto the underlayer-coated wafer at 1500 rpm for 60 seconds, and then baked at 110°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 6 shows the line-space focus exposure matrix (FEM) for underlayer material 2. Figure 7 shows the critical dimension (CD) versus focus plot. Figure 8 shows the line with roughness (LWR) versus focus plot. Figure 9 shows cross-sectional scanning electron microscope (SEM) images of the final features at the best dose and focus at a magnification of 500 kx.

[0110] [Example 11] Comparison of monomer sublayer 2 with standard spin-on EUV sublayer Compared to a standard spin-on silicon-containing EUV underlayer as described in U.S. Patent No. 11,361,967 (Brewer Science, Laura, Missouri), monomer underlayer 2, applied as described in Example 11, showed a large process window, a dramatic increase in depth of focus (DOF), and a decrease in LWR at similar doses. Defect-free depth of focus (DOF), i.e., the range of focus that maintains a resist profile of a given feature without nanobridges or line breaks, was defined as the set of dies with biased roughness (LWR) of <4 nm. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 8 shows a dose vs. CD comparison for the two materials. Figure 11 shows defect-free DOF vs. CD for the two materials. Figure 12 shows a line-with-roughness (LWR) vs. CD comparison for the two materials. Figure 13 shows the lithographic performance of monomer underlayer 2 at different bake temperatures. As shown in Figures 14(A) to (C), the lithography performance of monomer sublayer 2 is strongly dependent on the bake temperature, with monomer sublayer 2 exhibiting best performance (highest DOF and lowest LWR) at 180°C.

[0111] Monomer underlayer 2 was used to pattern contact holes in the CD range of 15.4–23.3 nm. Figure 15 shows the contact hole FEM of monomer underlayer 2. Corona comparisons were performed to review defects by measuring 19 CD-SEM images / chips (a total of 8600 contact holes were measured), and the percentage of defective contact holes was plotted against CD. As shown in Figure 16, monomer underlayer 2 gives a similar defect-free range (defect %=0) compared to conventional EUV underlayers, demonstrating a comparable large process window for monomer underlayer 2. Figure 17 shows the EUV lithography results for monomer underlayer 2 for contact holes. Figure 18 shows the Bossong plot of contact holes CD vs. focus for monomer underlayer 2.

[0112] Monomer underlayer 2 showed a significant increase in DOF and much lower critical dimension uniformity (CDU) compared to the standard spin-on underlayer thin film. Figure 19 shows a comparison of CDU-DOF vs. CD between monomer underlayer 2 and the standard spin-on EUV underlayer, where CDU-DOF was defined as the set of dies with CDU < 3.5 nm. Figure 20 shows a comparison of CDU vs. CD between monomer underlayer 2 and the standard spin-on underlayer, where the unbiased 3-sigma LCDU was 1.932 as measured by Metro LER.

[0113] [Example 12] Synthesis of polymer 1 mother liquor In this example, a three-necked round-bottom flask was filled with 12.3 grams of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECHTMS) and 37.7 grams of PGME. The contents were stirred for 5 minutes to ensure thorough mixing of the solutions. Then, 9 grams of 0.01 M nitric acid (HNO3 aqueous solution) were added dropwise over 15 minutes while stirring at room temperature. Hydrolysis of the contents was continued for a further 45 minutes. The contents were then stirred at 300 rpm at 90°C for 11 hours.

[0114] [Example 13] Formulation of polymer sublayer 1 from polymer mother liquor 1 In this example, 0.339 grams of polymer 1 mother liquor from Example 12 was placed in a 100 mL Aicello bottle containing 9.666 grams of filtered PGME 8 and 9.995 grams of filtered PGMEA, and mixed overnight at room temperature on a roller. The material was then filtered through a 0.1 μm filter. The resulting underlayer-forming composition is suitable for spin-coating an adhesion-promoting layer (<2.5 nm) as described above and consists of the following polymers dissolved or dispersed in a solvent system. [ka]

[0115] [Example 14] Formation of polymer lower layer 2 from polymer mother liquor 1 In this example, 0.3271 grams of polymer mother liquor from Example 12 was placed in a 100 mL Aicello bottle containing 0.1244 grams of a 0.2% solution of R30N in PGME, 9.553 grams of filtered PGME 8, and 9.995 grams of filtered PGMEA, and these were mixed overnight at room temperature on a roller. The material was then filtered through a 0.1 μm filter. The resulting underlayer-forming composition is suitable for spin-coating an adhesion-promoting layer (<2.5 nm) as described above and consists of the following polymers dissolved or dispersed in a solvent system.

[0116] [Example 15] Formulation of polymer lower layer 3 from polymer mother liquor 1 In this example, 0.3255 grams of polymer mother liquor from Example 12 was placed in a 100 mL Aicello bottle containing 0.1980 grams of a 0.25% solution of TAG2689 in PGME, 9.482 grams of filtered PGME 8, and 9.995 grams of filtered PGMEA, and these were mixed overnight at room temperature on a roller. The material was then filtered through a 0.1 μm filter. The resulting underlayer-forming composition is suitable for spin-coating an adhesion-promoting layer (<2.5 nm) as described above and consists of the following polymers dissolved or dispersed in a solvent system. [ka]

[0117] [Example 16] Synthesis of polymer 2 mother liquor In this example, a three-necked round-bottom flask was packed with 15.00 grams of (3-triethoxysilyl)propyl succinic anhydride (TEOSPSA) (Gelest) and 76.12 grams of filtered PGME. The contents were stirred for 5 minutes to ensure thorough mixing of the solutions. Then, 8.88 grams of 0.01 M HNO3 (aqueous solution) was added dropwise over 15 minutes while stirring at room temperature. Hydrolysis of the contents was continued for a further 45 minutes. The contents were then stirred under a flow of N2 at 300 rpm at 90°C for 5.5 hours.

[0118] [Example 17] Formulation of polymer lower layer 4 from polymer mother liquor 2 In this example, 0.39 grams of polymer 2 mother liquor from Example 16 was placed in an Aicello bottle containing 9.41 grams of filtered PGME, 9.99 grams of filtered PGMEA, 0.06 grams of 2% maleic acid in PGME, and 0.15 grams of 0.2% ethyltriphenylphosphonium bromide (EtPPB) in PGME, and these were mixed on a roller at room temperature for one hour. The material was then filtered through a 0.1 μm filter. The resulting underlayer-forming composition is suitable for spin-coating an adhesion-promoting underlayer (<2.5 nm) as described above and contains the following polymers dissolved or dispersed in a solvent system.

[0119] [Example 18] Formulation of polymer lower layer 5 from polymer mother liquor 2 In this example, 2.6547 grams of polymer 2 mother liquor from Example 16 was placed in a 100 mL Aicello bottle containing 1.9972 grams of a 0.2% solution of EtPPB (ethyltriphenylphosphonium bromide) in PGME, 0.3950 grams of a 2.0% solution of maleic acid in PGME, 179.480 grams of filtered PGME, and 21.210 grams of filtered PGMEA. This mixture was then mixed overnight at room temperature on a roller. The material was then filtered through a 0.1 μm filter. The resulting underlayer-forming composition is suitable for spin-coating an adhesion-promoting layer (<2.5 nm) as described above and consists of the following polymers dissolved or dispersed in a solvent system.

[0120] [Example 19] Synthesis of polymer mother liquor In this example, a three-necked round-bottom flask was packed with 36.92 grams of (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione)(DAICATEOS)(Silar Laboratories) and 46.98 grams of filtered PGME. The contents were stirred for 5 minutes to ensure thorough mixing of the solutions. Then, 16.09 grams of 0.01 M HNO3 (aqueous solution) was added dropwise over 15 minutes while stirring at room temperature. Hydrolysis of the contents was continued for a further 45 minutes. The contents were then stirred under a flow of N2 at 300 rpm at 90°C for 11 hours.

[0121] [Example 20] Formulation of polymer lower layer 6 from polymer mother liquor 3 In this example, 0.27 grams of polymer 3 mother liquor from Example 19 was placed in an Aicello bottle containing 134.48 grams of filtered PGME, 14.99 grams of filtered PGMEA, 0.07 grams of 2% maleic acid in PGME, and 0.18 grams of 0.2% ethyltriphenylphosphonium bromide (EtPPB) in PGME, and these were mixed on a roller at room temperature for 1 hour. The material was then filtered through a 0.1 μm filter. The resulting underlayer-forming composition is suitable for spin-coating an adhesion-promoting underlayer (<2.5 nm) as described above and consists of the following polymers dissolved or dispersed in a solvent system. [ka]

[0122] [Example 21] Lithography test of polymer underlayer 1 on CAR resist Bare silicon wafers were primed with hexamethyldisilazane (HMDS) and baked at 135°C. Following the priming of the wafers, an experimental silicon hard mask ("SiHM") from Brewer Science was spin-coated onto the wafers at 1,391 rpm for 60 seconds and baked at 205°C for 60 seconds, targeting a 10 nm film thickness. Next, the formulation prepared in Example 13 was spin-coated onto the experimental hard mask as a base layer at 1,654 rpm for 60 seconds and baked at 205°C for 60 seconds, targeting a base layer thickness of less than 2.5 nanometers. Then, TOK Penta resist was spin-coated onto the primer-coated wafers at 1,500 rpm for 60 seconds and baked at 110°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 21 shows the EUV lithography focal exposure matrix (FEM), and Figure 22 shows the scanning electron microscope (SEM) image at the central dose / central focus.

[0123] [Example 22] Lithography test of polymer underlayer 1 on CAR resist The formulation prepared in Example 13 was spin-coated onto a 100 mm unused (untreated) silicon wafer at 1,983 rpm for 60 seconds and baked at 205°C for 60 seconds to form a sublayer less than 2.5 nanometers thick with uniform thickness and low surface roughness. Then, the TOK Penta resist was spin-coated onto the primer-coated wafer at 1,500 rpm for 60 seconds and baked at 110°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 23 shows the EUV lithography focus exposure matrix (FEM), and Figure 24 shows the scanning electron microscope (SEM) image at the central dose / central focus.

[0124] [Example 23] Lithography of polymer underlayer 1 on MOR resist The formulation prepared in Example 13 was spin-coated onto a 100 mm unused (untreated) silicon wafer at 1,983 rpm for 60 seconds and baked at 205°C for 60 seconds to form an underlayer less than 2.5 nanometers thick with uniform thickness and low surface roughness. The Inpria YATU1011 resist was coated at 1,500 rpm for 60 seconds and baked at 100°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 25 shows the EUV lithography focus exposure matrix (FEM), and Figure 26 shows the scanning electron microscope (SEM) image at the central dose / central focus.

[0125] [Example 24] Lithography of polymer underlayer 2 on CAR resist The formulation prepared in Example 14 was spin-coated onto a 100 mm unused (untreated) silicon wafer at 1,983 rpm for 60 seconds and baked at 205°C for 60 seconds to form a sublayer less than 2.5 nanometers thick with uniform thickness and low surface roughness. Then, the TOK Penta resist was spin-coated onto the primer-coated wafer at 1,500 rpm for 60 seconds and baked at 110°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 27 shows the EUV lithography focus exposure matrix (FEM), and Figure 28 shows the scanning electron microscope (SEM) image at the central dose / central focus.

[0126] [Example 25] Lithography of polymer underlayer 2 on CAR resist An experimental silicon hard mask ("SiHM") from Brewer Science was spin-coated onto a bare silicon wafer at 1,391 rpm for 60 seconds and baked at 205°C for 60 seconds, aiming for a 10 nm film thickness. Next, the formulation prepared in Example 14 was spin-coated onto the experimental hard mask as an underlayer at 1,654 rpm for 60 seconds and baked at 205°C for 60 seconds, aiming for an underlayer thickness of less than 2.5 nanometers. Then, TOK Penta resist was spin-coated onto the coated wafer at 1,500 rpm for 60 seconds and baked at 110°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 29 shows the EUV lithography focus exposure matrix (FEM), and Figure 30 shows the scanning electron microscope (SEM) image at the central dose / central focus.

[0127] [Example 26] Lithography of polymer underlayer 4 on MOR resist The formulation prepared in Example 17 was spin-coated onto a 100 mm unused (untreated) silicon wafer at 1,500 rpm for 60 seconds and baked at 205°C for 60 seconds to form an underlayer less than 2.5 nanometers thick with uniform thickness and low surface roughness. The Inpria YATU1011 resist was coated at 1,500 rpm for 60 seconds and baked at 100°C for 60 seconds. EUV lithography was performed at IMEC using an NXE3400 scanner system. Figure 31 shows the EUV lithography focus exposure matrix (FEM), and Figure 32 shows the scanning electron microscope (SEM) image at the central dose / central focus.

[0128] [Example 27] Metal diffusion into the lower stack An experimental silicon hard mask ("SiHM") manufactured by Brewer Science was spin-coated onto a wafer at 1,500 rpm for 60 seconds, and then baked at 205°C for 60 seconds, aiming for a 10 nm film. Next, the formulation prepared in Example 13 was spin-coated onto the experimental hard mask as a base layer at 1,500 rpm for 60 seconds, and then baked at 205°C for 60 seconds, aiming for a base layer with a thickness of less than 2 nanometers. Then, Inpria YATU1011 resist was spin-coated onto a primer-coated wafer at 1,500 rpm for 30 seconds, baked at 100°C for 60 seconds, and then baked at 180°C for 60 seconds.

[0129] A Brewer Science experimental silicon hard mask ("SiHM") was spin-coated onto a control wafer at 1,500 rpm for 60 seconds, and baked at 205°C for 60 seconds to achieve a target film thickness of 10 nm. Subsequently, without applying an underlayer as described herein, an Inpria YATU1011 resist was spin-coated onto a primer-coated wafer at 1,500 rpm for 30 seconds, baked at 100°C for 60 seconds, and then baked at 180°C for 60 seconds.

[0130] Both wafers were subjected to a development step including paddle immersion in IDS-033-AA developer (Inpria, Corvallis, Oregon) for 20 seconds, followed by rinsing for 5 seconds and then spin-drying for 45 seconds to remove the resist. The wafers were then baked at 250°C for 60 seconds. Both wafers were then subjected to XPS analysis of the surface (for stack 1) and the underlying layer (for stack 2) beneath the Si-HM layer. As shown in Figure 33, when used, the underlying layer reduces Sn contamination in the surface layer by at least approximately 25% and up to approximately 75%. Furthermore, the underlying layer can prevent cross-mixing between the EUV photoresist layer and any intermediate layer beneath it.

Claims

1. A method for forming a structure, The method described above is Forming a lower layer on top of a stack, Forming a photoresist layer on the aforementioned lower layer, and This includes subjecting at least a portion of the photoresist layer to EUV irradiation. The aforementioned lower layer is, (a) A polymer, oligomer, or mixture thereof comprising at least about 75 mol% of a monomer having an adhesive portion and a surface-modifying group selected from a silanol portion, a Si-O portion, or both. (b) A monomer compound comprising an adhesive portion and a surface-modifying group selected from a silanol portion, an SiO portion, or both, or (c) A method comprising a composition comprising a component selected from a combination of (a) and (b).

2. (i) The monomer further comprises an alkyl having first and second terminals, wherein the surface modification group is at the first terminal and the adhesive portion is at the second terminal, (ii) The monomer compound further comprises an alkyl having first and second terminals, wherein the surface modifying group is at the first terminal and the adhesive portion is at the second terminal, or The method according to claim 1, wherein both (iii)(i) and (ii) are true.

3. The method according to claim 1 or 2, wherein the adhesive portion comprises one or more epoxy groups, isocyanurate groups, benzene groups, carbomethoxy groups, vinyl groups, anhydride groups, carboxylic acid groups, chlorine atoms, or mixtures thereof.

4. (I) The monomer comprises at least two surface-modifying groups, (II) The monomer compound comprises at least two surface modifying groups, or (III) The method according to any one of claims 1 to 3, wherein both (I) and (II) are met.

5. (A) The monomer includes hydrolyzed forms of glycidylpropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)trimethoxysilane, 2-chloroethyltrimethoxysilane, 3-acetoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-phenylpropyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, [(3-triethoxysilyl)propyl]succinic anhydride, or combinations thereof. (B) The monomer compound includes glycidylpropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)methyl-dimethoxysilane, 2-chloroethylmethyldimethoxysilane, 3-acetoxypropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-phenylpropylmethyldimethoxysilane, 4-amino-3,3-dimethylbutylmethyldimethoxysilane, vinylmethyldimethoxysilane, dimethyl-dimethoxysilane, phenylmethyldimethoxysilane, or a hydrolyzed form of a combination thereof, or (C) The method according to any one of claims 1 to 4, wherein both (A) and (B) are met.

6. The method according to any one of claims 1 to 5, wherein the polymer is a homopolymer, the oligomer is a homooligomer, or both.

7. The method according to any one of claims 1 to 6, wherein the lower layer has an average thickness of approximately 4.5 nm or less.

8. The method according to any one of claims 1 to 7, wherein the lower layer is a single layer.

9. The method according to any one of claims 1 to 8, wherein the composition essentially consists of the component and a catalyst dispersed or dissolved in a solvent system.

10. The method according to any one of claims 1 to 8, wherein the composition essentially consists of the component dispersed or dissolved in a solvent system, a catalyst, and a surfactant.

11. If the component is a polymer and the monomer is 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane or a hydrolyzed form of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, then at least one of the following is true: The polymer has a weight-average molecular weight of less than approximately 2,000 daltons. The aforementioned lower layer shows a peeling percentage of less than approximately 30%. The polymer is crosslinked in the lower layer, or The method according to any one of claims 1 to 10, wherein the polymer is branched.

12. The aforementioned stack A substrate having a surface, and Optionally, the surface may include one or more intermediate layers. The method according to any one of claims 1 to 11, wherein if one or more intermediate layers are present, the uppermost intermediate layer is on the surface; if a lower layer is present, the lower layer is on the uppermost intermediate layer; or if no intermediate layers are present, the lower layer is on the surface.

13. The substrate is silicon, SiGe, SiO ２ Si ３ N ４ SiO, SiCO:H, combination of tetramethyl silate and tetramethylcyclotetrasiloxane, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, tantalum nitride, Ti ３ N ４ , hafnium, HfO ２ The method according to claim 12, comprising ruthenium, indium phosphide, or glass.

14. After subjecting the photoresist layer to EUV irradiation, a pattern is formed on the photoresist layer, and The aforementioned pattern In the lower layer, If present, in the intermediate layer, and The method according to claim 12 or 13, comprising transferring to the substrate.

15. The method according to any one of claims 12 to 14, wherein the stack includes one or more intermediate layers on the surface, and the one or more intermediate layers include a hard mask layer.

16. The method according to any one of claims 1 to 15, wherein the photoresist layer contains a metal.

17. The method according to claim 16, wherein the photoresist layer contains a metal oxide.

18. A substrate having a surface, Optionally, one or more intermediate layers on the substrate surface, and if one or more intermediate layers exist, the uppermost intermediate layer is located on the substrate surface, The lower layer on the substrate surface, or, if present, on the uppermost intermediate layer, the lower layer is (a) A polymer, oligomer, or mixture thereof comprising at least about 75 mol% of a monomer having an adhesive portion at the first end of the alkyl group and a Si-O portion at the second end of the alkyl group. (b) A monomer compound having an adhesive portion at the first end of the alkyl group and a Si-O portion at the second end of the alkyl group, or (c) A lower layer including the combination of (a) and (b), A structure comprising the aforementioned lower layer of photoresist.

19. The photoresist has a wavelength of less than approximately 20 nm and / or approximately 5 mJ / cm². ２ ~Approx. 100mJ / cm ２ The structure according to claim 18, which can be patterned with the exposure amount.

20. The structure according to claim 18 or 19, wherein the adhesive portion is generally oriented toward the photoresist layer.

21. The structure according to any one of claims 18 to 20, wherein, if present, the Si-O portion is generally oriented toward the uppermost intermediate layer, or, if the intermediate layer is absent, the Si-O portion is oriented toward the substrate surface.

22. The substrate is silicon, SiGe, SiO ２ , Si ３ N ４ , SiON, SiCO:H, a combination of tetramethylsilicate and tetramethyl-cyclotetrasiloxane, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, tantalum nitride, Ti ３ N ４ , hafnium, HfO ２ , ruthenium, indium phosphide, or glass, the structure according to any one of claims 18 to 21.

23. The structure according to any one of claims 18 to 22, wherein the adhesive portion comprises one or more epoxy groups, isocyanurate groups, benzene groups, carbomethoxy groups, vinyl groups, anhydride groups, carboxylic acid groups, chlorine atoms, or mixtures thereof.

24. (I) The monomer comprises at least two Si-O moieties, (II) The monomer compound comprises at least two Si-O moieties, or The structure according to any one of claims 18 to 23, which is both (III)(I) and (II).

25. (A) The monomer includes hydrolyzed forms of glycidylpropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)trimethoxysilane, 2-chloroethyltrimethoxysilane, 3-acetoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-phenylpropyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, [(3-triethoxysilyl)propyl]succinic anhydride, or combinations thereof. (B) The monomer compound includes glycidylpropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)methyl-dimethoxysilane, 2-chloroethylmethyldimethoxysilane, 3-acetoxypropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-phenylpropylmethyldimethoxysilane, 4-amino-3,3-dimethylbutylmethyldimethoxysilane, vinylmethyldimethoxysilane, dimethyl-dimethoxysilane, phenylmethyldimethoxysilane, or a hydrolyzed form of a combination thereof, or (C) The structure according to any one of claims 18 to 24, which is both (A) and (B).

26. The structure according to any one of claims 18 to 25, wherein the polymer is a homopolymer, the oligomer is a homooligomer, or both.

27. The structure according to any one of claims 18 to 26, wherein the lower layer has an average thickness of approximately 4.5 nm or less.

28. The structure according to any one of claims 18 to 27, wherein the lower layer is a single layer.

29. If the lower layer contains the polymer and the monomer is derived from a hydrolyzed form of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, then at least one of the following is true: The aforementioned lower layer shows a peeling percentage of less than approximately 30%. The polymer is crosslinked in the lower layer, or The structure according to any one of claims 18 to 28, wherein the polymer is branched.

30. The stack includes one or more intermediate layers on the surface, and the one or more intermediate layers are Spin-on carbon layer, hard mask layer, or The structure according to any one of claims 18 to 29, comprising both the spin-on carbon layer and the hard mask layer on the spin-on carbon layer.

31. The structure according to any one of claims 18 to 30, wherein the photoresist layer contains a metal.

32. A method for hydrolyzing silane, wherein the method is The method involves combining the silane with an acid and at least one solvent, and hydrolyzing the silane for at least 60 minutes. The silanes mentioned above are glycidylpropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)methyl-dimethoxysilane, 2-chloroethylmethyldimethoxysilane, 3-acetoxypropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-phenylpropylmethyldimethoxysilane, 4-amino-3,3-dimethylbutylmethyldimethoxysilane, vinylmethyldimethoxysilane, and di Selected from methyl-dimethoxysilane, phenylmethyldimethoxysilane, glycidylpropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, (methacryloxymethyl)trimethoxysilane, 2-chloroethyltrimethoxysilane, 3-acetoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-phenylpropyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, [(3-triethoxysilyl)propyl]succinic anhydride, or combinations thereof. A method for hydrolyzing a silane, wherein the acid is selected from maleic acid, nitric acid, hydrochloric acid, acetic acid, sulfuric acid, or a combination thereof.

33. The above combination forms a reagent, The silane is selected from glycidylpropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)methyl-dimethoxysilane, 2-chloroethylmethyldimethoxysilane, 3-acetoxypropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-phenylpropylmethyldimethoxysilane, 4-amino-3,3-dimethylbutylmethyldimethoxysilane, vinylmethyldimethoxysilane, dimethyl-dimethoxysilane, phenylmethyldimethoxysilane, or a combination thereof. The silane is incorporated into the reaction mixture at a level of about 1% to about 15% by weight relative to the total weight of the reaction mixture. The method according to claim 32, wherein the acid is added to the reaction mixture at a level of about 0.001 mol% to about 0.1 mol% relative to the total moles of silane.

34. The above combination forms a reagent, The silane is selected from glycidylpropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, phenyltrimethoxysilane, (1,3-di-2-propen-1-yl)-5-(([3-triethoxysilylpropyl])-(1,3,5-triazine-2,4,6(1H,3H,5H)-trione), (methacryloxymethyl)trimethoxysilane, 2-chloroethyltrimethoxysilane, 3-acetoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-phenylpropyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, [(3-triethoxysilyl)propyl]succinic anhydride, or a combination thereof. The silane is added to the reaction mixture at a level of about 1% to about 25% by weight relative to the total weight of the reaction mixture. The acid is added to the reaction mixture in an amount of about 0.5 equivalents to about 20 equivalents relative to the total monomer. The method according to claim 32, wherein the reaction is carried out at a temperature of about 20°C to about 100°C.

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