Radiation sensitive organotin compositions having oxygen heteroatoms in hydrocarbyl ligand and application thereof

Abstract

The expression RSnL is explained 3. Organotin compositions and corresponding synthesis methods. R comprises an aromatic ether moiety, a cyclic ether moiety, and / or a halide ether moiety or a polyether, and L comprises a hydrolyzable group. The organotin composition can be formed on a substrate as a radiation-patternable coating. The coating can have an average thickness of about 1 nanometer to about 75 nanometers and has the formula RSnO. n(OH) A 3-2n oxo-hydroxyl network is formed, wherein R is a hydrocarbon ether group having 1 to 30 carbon atoms and 0 < n < 3 / 2. In the liquid-coating development step performed after baking at 150°C for 120 seconds, the regions of the coating are soluble in 2-heptanone. The coating can be irradiated and patterned using ultraviolet, extreme ultraviolet, or ion beam radiation, and the corresponding methods are described.

Description

Technical Field

[0001] The present invention relates to an organotin composition and its application. Prior Art

[0002] Organometallic compounds provide metal ions in solution and vapor form for thin film deposition. Organotin compounds provide high EUV (extreme ultraviolet) absorption and radiation-sensitive tin-ligand bonds, which can be used for lithographic patterning of thin films. Fabricating semiconductor devices with ever-shrinking dimensions using EUV radiation requires new materials with wide process latitude to achieve the required patterning resolution and low defect density. Summary of the Invention

[0003] One aspect of the present invention relates to an organotin composition having a hydrocarbyl group represented by the formula R1-OR2SnL3, wherein the hydrocarbyl group comprises a Sn-C bond and one or more carbon atoms are substituted with oxygen heteroatoms, wherein R1 is selected from a linear, aromatic, cyclic, branched, or unsaturated hydrocarbyl ligand having 1 to 30 carbon atoms and optionally further substituted with one or more heteroatoms (e.g., O, F, I, Si, Sn, Te, and / or Sb), R2 is a hydrocarbyl ligand having a Sn-C bond and 2 to 5 carbon atoms, and L is a hydrolyzable ligand. In some particularly interesting embodiments, R1-OR2- forms a C-Sn bond and introduces cyclic ethers, aromatic ethers, and polyethers, which can provide the desired ligands for the tin patterning composition. Organotin compounds can have R 1-OR 2-ligands selected to impart solubility in polar solvents. Organotin compounds having ether ligands containing C—Sn bonds and three hydrolyzable ligands can be formulated with R OSnL'3 compounds into precursor blends to tailor desired precursor properties for patterning, particularly patterning using EUV radiation.

[0004] Another embodiment of the present invention relates to a composition comprising a solvent and an organotin composition represented by the formula R1-OR2SnL3, wherein R1 is selected from a linear hydrocarbon ligand, an aromatic hydrocarbon ligand, a cyclic hydrocarbon ligand, a branched hydrocarbon ligand, or an unsaturated hydrocarbon ligand having 1 to 30 carbon atoms and optionally further substituted with one or more heteroatoms (e.g., O, F, I, Si, Sn, Te, and / or Sb), R2 is a hydrocarbon ligand having a Sn-C bond and 2 to 5 carbon atoms, and L is a hydrolyzable ligand.

[0005] Another embodiment of the present invention relates to a high-purity organotin composition having a hydrocarbon group containing a Sn-C bond and one or more carbon atoms substituted with oxygen heteroatoms, and having a purity greater than 99.9999% calculated as metal.

[0006] Another embodiment of the present invention relates to a method for forming a coating on a substrate, wherein the method comprises hydrolyzing a composition represented by the formula R1-OR2SnL3, wherein R1 is selected from a linear hydrocarbon ligand, an aromatic hydrocarbon ligand, a cyclic hydrocarbon ligand, a branched hydrocarbon ligand, or an unsaturated hydrocarbon ligand having 1 to 30 carbon atoms and optionally further substituted with one or more heteroatoms (e.g., O, F, I, Si, Sn, Te, and / or Sb), R2 is a hydrocarbon ligand having a Sn-C bond and 2 to 5 carbon atoms, and L is a hydrolyzable ligand.

[0007] Another embodiment of the present invention relates to a coating on a substrate, wherein the coating comprises a composition containing an R1-OR2Sn moiety, wherein R1 is selected from a linear hydrocarbyl ligand, an aromatic hydrocarbyl ligand, a cyclic hydrocarbyl ligand, a branched hydrocarbyl ligand, or an unsaturated hydrocarbyl ligand having 1 to 30 carbon atoms and optionally further substituted with one or more heteroatoms (e.g., O, F, I, Si, Sn, Te, and / or Sb), and R2 is a hydrocarbyl ligand having a Sn-C bond and 2 to 5 carbon atoms.

[0008] Another embodiment of the present invention relates to a method for patterning an organotin composition comprising an R1-OR2Sn moiety, wherein R1 is selected from a linear hydrocarbyl ligand, an aromatic hydrocarbyl ligand, a cyclic hydrocarbyl ligand, a branched hydrocarbyl ligand, or an unsaturated hydrocarbyl ligand having 1 to 30 carbon atoms and further optionally substituted with one or more heteroatoms (e.g., O, F, I, Si, Sn, Te, and / or Sb), R2 is a hydrocarbyl ligand having a Sn-C bond and 2 to 5 carbon atoms, and wherein patterning is performed using UV (ultraviolet), EUV, or ion beam radiation.

[0009] In another embodiment, the present invention relates to an organotin composition represented by the formula RSnL 3, wherein L is a hydrolyzable ligand and R is (A) an aromatic ether represented by the formula Ar-O-(CR' 2) m-, (B) a cyclic ether represented by the formula cyclo(O(CR" 2) nCR'R 0-), (C) a halogenated ether represented by the formula R 1OR 0C(R 2R 3)-, or (D) a polyether represented by the formula R 1R 2R 3C-, wherein Ar is an aromatic organic moiety; m is an integer from 1 to 4; R' is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and optionally heteroatoms; n is an integer from 1 to 8; R" is hydrogen or a hydrocarbon group having 1 to 4 carbon atoms and optionally heteroatoms; optionally, CR" The R2 group may be substituted by O to form a cyclic polyether, and two R" groups may be combined to form a polycyclic structure; R0 is a bond or a hydrocarbon group having 1 to 5 carbon atoms and optionally heteroatoms; R1 is a hydrocarbon group having 1 to 10 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms; R2 and R3 are independently hydrogen, halogen, or a hydrocarbon group having 1 to 7 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, wherein at least one of R1, R2, and R3 has a halogen atom; and R1, R2, and R3 are independently a hydrocarbon group having 1 to 19 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, at least two of R1, R2, and R3 are ether moieties, or at least one of R1, R2, and R3 is a diether moiety. Solutions comprising organotin compositions in organic solvents are also described.

[0010] In another embodiment, the present invention relates to a radiation-patternable coated substrate comprising a substrate and a coating comprising any one or more of the above-mentioned organotin compositions.

[0011] In yet another embodiment, the present invention relates to a radiation-patternable coated substrate comprising a substrate and a coating layer having an average thickness of from about 1 nanometer to about 75 nanometers and formed of the formula RSnO n(OH) 3-2n to form an oxo-hydroxo network, where R is a hydrocarbyl ether group having from 1 to 30 carbon atoms and 0 < n < 3 / 2, and wherein in a puddle development step carried out after baking at 150 °C for 120 seconds, the regions of the coating layer are soluble in 2-heptanone.

[0012] In another embodiment, the present invention relates to a method of forming a radiation-patternable coated substrate comprising a substrate and a coating layer comprising any one or more of the above-described organotin compositions.

[0013] In yet another embodiment, the present invention relates to a method of forming a radiation-patternable coated substrate, the method comprising: (A) contacting the surface of the substrate with the vapor of an organotin composition described herein to form a deposit on the surface of the substrate; and heating the substrate having the deposit on its surface, wherein the conditions of the contact and / or heating provide hydrolysis of the hydrolyzable ligand L to form a coating layer comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, where 0 < n < 3 / 2; or (B) depositing a solution onto the surface of the substrate to form an initial coated surface, the solution comprising an organic solvent and an organotin composition described herein having a concentration, measured based on the tin cation concentration, of from about 0.0025 M to about 1.4 M; and heating the substrate having the initial coated surface, wherein the conditions of the deposition and / or heating provide hydrolysis of the hydrolyzable ligand L to form a coating layer comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, where 0 < n < 3 / 2.

[0014] In yet another aspect, the present invention relates to a method of patterning a substrate, the method comprising: irradiating a substrate having an organotin coating with patterned EUV radiation to form a latent image, wherein the coating has an average thickness of from about 1 nanometer to about 75 nanometers and a composition represented by the formula RSnO n(OH) 3-2n, forming an oxo-hydroxo network, wherein R is a hydrocarbyl ether group having from 1 to 30 carbon atoms, and 0 < n < 3 / 2; and developing the latent image with a developer solvent to remove the unirradiated coating to form a developed image, thereby forming an image having a critical dimension (CD) not exceeding about 50 nanometers and a dose not exceeding about 80 millijoules per square centimeter (mJ / cm 2). The organotin coating can be formed by the following steps: A) contacting the surface of the substrate with the vapor of an organotin composition to form a deposit on the surface of the substrate; and heating the substrate having the deposit on the surface, wherein the conditions of the contact and / or heating provide hydrolysis of the hydrolyzable ligand L to form a coating comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, wherein 0 < n < 3 / 2; or (B) depositing a solution onto the surface of the substrate to form an initial coated surface, the solution comprising an organic solvent and an organotin composition having a concentration, measured based on the tin cation concentration, of from about 0.0025 M to about 1.4 M; and heating the substrate having the initial coated surface, wherein the conditions of the deposition and / or heating provide hydrolysis of the hydrolyzable ligand L to form a coating comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, wherein 0 < n < 3 / 2.

[0015] In another embodiment, the present invention relates to a method for synthesizing an organotin composition, comprising reacting a halide hydrocarbyl compound (RX, wherein X is a halogen atom) with an organometallic composition (comprising a SnL3 moiety bound to a metal cation M) to form an alkali tin composition, wherein M is an alkali metal, alkaline earth metal, and / or pseudo-alkaline earth metal (Zn, Cd, or Hg), and L is an amide ligand that produces an alkali tin triamide compound or an acetylide ligand that produces an alkali tin triacetylide compound, to form a monohydrocarbyltin triamide (RSn(NR'2)3) or a monohydrocarbyltin triacetylide (RSn(C≡CRs)3), respectively, and Rs is SiR' 3 or R', three R" are independently H or R', and R' is independently a hydrocarbon group having 1 to 31 carbon atoms and optionally an unsaturated carbon-carbon bond, optionally an aromatic group and optionally a heteroatom, and wherein R is a hydrocarbon ether group having 1 to 31 carbon atoms and optionally an unsaturated carbon-carbon bond, optionally an aromatic group and optionally a heteroatom, which includes an aromatic ether represented by the formula Ar-O-(CR'2)m-, or a hydrocarbon ether represented by the formula cyclo(O(CR'2) A cyclic ether represented by the formula R1R2R3C-) or a polyether represented by the formula R1R2R3C-, wherein Ar is an aromatic organic moiety, m is an integer from 1 to 4, each R' is hydrogen, a halogen, or a hydrocarbon group having 1 to 6 carbon atoms and optionally heteroatoms, n is an integer from 1 to 8, R1, R2, and R3 are independently hydrocarbon groups having 1 to 19 carbon atoms, and at least two of R1, R2, and R3 are ether moieties, or at least one of R1, R2, and R3 is a diether moiety. This method can be used to produce any of the organotin compositions described herein.

[0016] In another embodiment, the present invention relates to a method for synthesizing an organotin composition, comprising reacting an alkylating agent selected from the group consisting of RMgX, R2Zn, RZnNR'2, or a combination thereof, with Sn(NR'2)4 in a solution comprising an organic solvent, wherein X is a halogen, wherein R' is a hydrocarbon group having 1 to 10 carbon atoms, and wherein R is a hydrocarbon ether group having 1 to 31 carbon atoms and optionally an unsaturated carbon-carbon bond, optionally an aromatic group, and optionally a heteroatom, including an aromatic ether represented by the formula Ar-O-(CR'2)m-, or a hydrocarbon ether represented by the formula cyclo(O(CR'2) A cyclic ether represented by the formula R1R2R3C-) or a polyether represented by the formula R1R2R3C-, wherein Ar is an aromatic organic moiety, m is an integer from 1 to 4, each R' is hydrogen, a halogen, or a hydrocarbon group having 1 to 6 carbon atoms and optionally heteroatoms, n is an integer from 1 to 8, R1, R2, and R3 are independently hydrocarbon groups having 1 to 19 carbon atoms, and at least two of R1, R2, and R3 are ether moieties, or at least one of R1, R2, and R3 is a diether moiety. This method can be used to produce any of the organotin compositions described herein. Simple diagram description

[0017] Figure 1 is the 1H NMR (nuclear magnetic resonance) spectrum of methoxyethyltin tris(trimethylsilylacetylide) synthesized in Example 1 in benzene-d 6. Figure 2 shows the 119Sn NMR spectrum of methoxyethyltin tris(trimethylsilyl acetylide) in benzene-d 6 . Figure 3 shows the 1H NMR spectrum of methoxyethyltin tris(tertiary butyl oxide) in benzene-d 6 . Figure 4 shows the 119Sn NMR spectrum of methoxyethyltin tris(tertiary butyl oxide) in benzene-d 6 . Figure 5 is the 1H NMR spectrum of methoxypropyltin tris(trimethylsilyl acetylide) synthesized in Example 1 in benzene-d 6. Figure 6 shows the 119Sn NMR spectrum of methoxypropyltin tris(trimethylsilyl acetylide) in benzene-d 6 . Figure 7 is the 1H NMR spectrum of tetrahydropropyltin tris(tertiary butyl oxide) in benzene-d 6. Figure 8 is the 119Sn NMR spectrum of tetrahydropropyltin tris(tertiary butyl oxide) in benzene-d 6 . Figure 9 is the 1H NMR spectrum of methyl-tert-butyl ethertin tris(trimethylsilyl acetylide) synthesized in Example 1 in benzene-d6. Figure 10 shows the 119Sn NMR spectrum of methyl-tert-butyl ethertin tris(trimethylsilyl acetylide) in benzene-d 6 . Figure 11 shows the 1H NMR spectrum of methyl-tert-butyl ethertin tris(tert-butyl oxide) in benzene-d6. Figure 12 shows the 119Sn NMR spectrum of methyl-tert-butyl ether tin tris(tert-butyl oxide) in benzene-d 6 . Figure 13 is the 1H NMR spectrum of methylphenyltin tris(trimethylsilyl acetylide) synthesized in Example 1 in benzene-d6. Figure 14 shows the 119Sn NMR spectrum of methylphenyltin tris(trimethylsilyl acetylide) in benzene-d 6 . Figure 15 shows the 1H NMR spectrum of methylphenyltin tris(tertiary butyl oxide) in benzene-d6. Figure 16 shows the 119Sn NMR spectrum of methylphenyltin tris(tertiary butyl oxide) in benzene-d 6 . Figure 17 is the 1H NMR spectrum of dimethoxyethyltin tris(trimethylsilyl acetylide) synthesized in Example 1 in benzene-d6. Figure 18 is the 119Sn NMR spectrum of dimethoxyethyltin tris(trimethylsilyl acetylide) in benzene-d 6 . FIG. 19 is a set of comparative curves of tetrahydropyranyltin tris(tertiary butyl oxide) films prepared using three different post-exposure bake (PEB) temperatures: 140°C, 160°C, and 180°C. FIG. 20 is a plot of the relative peak area of ​​films prepared using methoxymethyltin tris(tertiary butyl oxide), tetrahydropyranyltin tris(tertiary butyl oxide), and 4-methyl-tetrahydropyranyltin tris(tertiary butyl oxide) as a function of dosage. Implementation Method

[0018] Organotin compositions containing oxygen-containing ligands while forming C-Sn bonds can provide desirable patterning properties related to solubility for some patterning applications. Specifically, specific ether ligands can provide desired precursor solution stability and facilitate solubility of the baked, unirradiated coating in the desired developer solvent. To achieve these properties, the selected ether ligand may have an aromatic ether structure or an alkyl group in which the ether oxygen atom is not directly bonded to the carbon atom providing the C-Sn bond. In some embodiments, the ether ligand may be a cyclic ether, a diether / polyether, or a fluorinated ether. This can result in favorable patterning results due to improved developer solvent usability. Organotin materials have been shown to be effective in photosensitive compositions, capable of producing high-resolution and smooth patterns while also exhibiting high sensitivity to suitable radiation sources, such as extreme ultraviolet (EUV) radiation.

[0019] Meyers et al. described radiation-sensitive organotin compositions useful as high-resolution and high-sensitivity photoresists in U.S. Patent No. 9,310,684, entitled "Organometallic Solution Based High Resolution Patterning Compositions," and U.S. Patent No. 10,228,618, entitled "Organotin Oxide Hydroxide Patterning Compositions, Precursors, and Patterning" (hereinafter referred to as the '618 Patent), both of which are incorporated herein by reference. Generally, radiation-sensitive organotin compositions include organic ligands bonded to Sn atoms via Sn-C and / or Sn-carboxylate bonds. It is generally believed that exposure of organotin materials to ionizing radiation (e.g., extreme ultraviolet (EUV), ultraviolet (UV), or ion beam) and subsequent processing results in Sn-C bond cleavage, forming a condensed metal oxo / hydroxyl network comprising Sn-O-Sn and Sn-OH bonds in the exposed areas. The increased concentration of these bonds results in a material that is more condensed and hydrophilic relative to the coated material, and thus produces a greater chemical and development contrast between irradiated and unirradiated areas. Therefore, it is desirable to increase the efficiency of Sn-C bond cleavage during irradiation. While not wishing to be bound by theory, it is believed that the efficiency of Sn-C bond cleavage is related to the stability of the hydrocarbon species bound to Sn via the Sn-C bond. In other words, a lower Sn-C bond dissociation energy (BDE) is expected to correlate with the increased sensitivity of organotin compositions to radiation. In some embodiments described herein, hydrocarbon groups having Sn—C bonds and containing oxygen heteroatoms can affect solubility in various ways, and they can improve solubility contrast during development.

[0020] It has also been discovered that using blends of patterning compositions provides an additional dimension for tailoring overall coating properties. While reasonable EUV patterning results have been achieved using oxygen-containing ligands with C-Sn bonds, the greatest value of these compounds may lie in blends with other ligands, allowing the overall solubility properties of coatings from patterning compositions to be tailored as desired. In a non-limiting, prophetic example, the inclusion of the organotin oxygen-heteroatom compositions described herein in compositions containing other organotin species that typically tend to form less soluble hydrolysis and condensation products (e.g., MeSnL3, tBuSnL3) can increase the overall solubility of the blended compositions and coatings, resulting in coatings and patterns with fewer defects (e.g., particles, scum, microbridging, etc.). Radiation-sensitive organotin materials are typically based on the conversion of hydrocarbyl-Sn bonds to Sn-O and / or Sn-OH bonds upon exposure to ionizing radiation, thereby providing chemical contrast between irradiated and unirradiated areas. Precursors used for lithographic patterning to form radiation-sensitive organotin compositions can generally be described by the formula RnSnL4-n, where n = 1, 2, or 3, R is a hydrocarbyl ligand with a Sn-C bond, and L is a ligand with a hydrolyzable or oxidizable Sn-L bond. For commercial implementations, implementations based on n being approximately 1 have shown minimal interest. For use in semiconductor lithography, radiation-patternable organotin coatings are typically produced by exposing the RnSnL4-n composition to water and / or other oxygen sources to drive hydrolysis and condensation processes that convert the monomeric organotin species into polymeric organotin oxo / hydroxyl networks. Generally, solution-based or vapor-phase deposition can be used. Hydrolysis to replace the hydrolyzable ligand with an oxo-hydroxyl network can be performed during and / or after deposition.

[0021] As described herein, novel photosensitive organotin compounds have one or more oxygen heteroatoms in an ether-linked structure within the hydrocarbyl ligand of the organotin compound. In particularly interesting embodiments, the ether structure in the R ligand comprises an aromatic or alkyl group (e.g., a cyclic alkyl group), wherein the oxygen atom is not directly bonded to the carbon bonded to the tin atom. Compositions having oxygen heteroatoms can be used in photoresist compositions, and the presence of oxygen heteroatoms in the organic group has been found to provide beneficial properties. Furthermore, the organotin compositions having oxygen heteroatoms described herein can be used as photoresist compositions, either by themselves or as part of a blended composition. The compositions described herein build upon earlier work by the applicant involving a hydrocarbyl ligand of tin with a C—Sn bond and three hydrolyzable ligands. Methyl methyl ether ligands are described in published U.S. Patent Application No. 2022 / 0064192 to Edson et al., entitled "Methods to Produce Organotin Compositions with Convenient Ligand Providing Reactants" (hereinafter referred to as the '192 application), which is incorporated herein by reference. Comparative examples of methyl methyl ether ligands are provided below. Compositions with improved oxygen-containing ligands are described herein. The methyl methyl ether ligands of the '192 application produce tin complexes after hydrolysis to form an oxo-hydroxyl coating with limited solubility in polar solvents, particularly after heating the coating at low to moderate temperatures (e.g., during a post-application bake or post-exposure bake). Alternative oxygen-containing ligands are described herein to provide improved solubility in polar solvents.

[0022] The patterning process relies on radiation-driven cleavage of hydrocarbyl ligands (R) bound to tin (Sn) atoms within the oxo-hydroxyl matrix of the patternable coating. Following radiation absorption, the considerable energy from the radiation is used to break carbon-tin bonds. The R-group then abstracts an atom or radical to stabilize the stray R, forming, for example, RH or ROH, which may be volatile, allowing the resulting compound to leave the coating. In turn, the Sn atom acquires a ligand, such as an -OH or -O bond. As a result, the irradiated coating becomes less organic and more characterized by condensed oxo-hydroxyl networks. This process assumes that stray R-type species can migrate out of the coating before rebonding to Sn, and the efficiency of this process facilitates patterning at lower radiation doses.

[0023] The escape efficiency of R-based leaving groups can be determined based on the chemical nature of the R-groups, the coating formation process (which can affect density), and post-irradiation processing, which can promote the escape of R-based species. The escape of R-based species can be tracked using spectroscopic techniques. Specifically, Fourier transform infrared (FTIR) spectroscopy can be used with intensity measurements from the spectrum to quantify the level of remaining organic groups. The known vibrational frequencies of hydrocarbon group vibrations can be used to adjust FTIR measurements, thereby enabling the monitoring of the organic content of the coating under different process conditions.

[0024] Direct removal of R-type species from radiation absorption is referred to as radiolysis, and the radiolysis efficacy of a specific radiation dose can be assessed after irradiation using FTIR, with measurements focused on the irradiated portion of the substrate. A post-exposure bake (PEB), performed after irradiation but before image development, can be used to enhance the escape of R-type species. Details of the post-exposure bake (PEB) are further described below. The PEB process can induce radiation-induced pyrolysis, which enhances the release of R-type species remaining in the irradiated areas of the coating. However, under typical PEB conditions, pyrolysis alone is ineffective in removing R-type species from the coating. In other words, organic species are typically less depleted from unirradiated coatings due to the presence of the PEB and the absence of irradiation. However, radiation-induced pyrolysis can significantly enhance the depletion of organic species from irradiated coatings, which can reduce the required treatment dose for the coating.

[0025] Generally speaking, the properties of radiation-patternable coating materials can be evaluated at various stages of processing. For example, the composition of the ligands affects the stability of the precursor solution and, therefore, its shelf life. As discussed below, the precursor solution is also affected by the solvent and the control of the water content. Applicants have made significant progress in controlling the water content, thereby improving the stability of the precursor solution while also achieving highly reproducible commercial precursor stability. See U.S. Patent No. 11,300,876 to Jiang et al., entitled "Stable Solutions of Monoalkyl Tin Alkoxides and Their Hydrolysis and Condensation Products," which is incorporated herein by reference. The precursor solution is then used to deposit a patternable coating onto a substrate. The deposited coating in this manner can be heated to aid in solvent removal. Generally, during deposition and / or solvent removal, hydrolyzable ligands are removed and replaced by oxo-hydroxy ligands within the network within the coating. Ambient water or delivered water (e.g., water vapor) may aid in the hydrolysis of the ligand. The properties of the precursor solution influence the properties of the resulting coating. Similarly, blends of precursors with different R groups may be beneficial for balancing process conditions.

[0026] In other embodiments, coatings comprising organotin compounds having hydrocarbyl ligands substituted with oxygen heteroatoms can exhibit improved thermal stability relative to similar compositions without oxygen-containing ligands. Generally, organotin compounds decompose upon heating to sufficiently high temperatures, whereby the Sn-C bonds cleave and the hydrocarbyl groups are released from the matrix, resulting in a predominantly inorganic Sn coating composition. For example, the hydrocarbyl ligands can be released from the coating, resulting in an increase in the oxide / hydroxide character of the coating composition (e.g., an increase in the number of Sn-O and / or Sn-OH bonds). Of course, the exact chemical composition of the coating may depend on a number of factors, such as the ambient atmospheric composition and the identity of the hydrocarbyl ligands. Some examples of the effects of different gases present in the atmosphere on organotin compositions are described in published U.S. patent application No. 2021 / 0271170 to Telecky et al. and entitled “Process Environment for Inorganic Resist Patterning,” which is incorporated herein by reference.

[0027] Furthermore, the presence of oxygen heteroatoms in the hydrocarbyl ligand can significantly improve the solubility of the organotin composition in selected solvents, as well as its solution stability (which can improve shelf life), relative to unsubstituted organotin compositions. For example, the presence of oxygen heteroatoms in the hydrocarbyl group can increase the polarity, hydrogen bonding properties, and / or hydrophilicity of the organotin oxy / hydroxy (i.e., hydrolyzed) composition, thereby increasing its solubility in suitable solvents. Normal processing and handling of organotin solutions can result in the absorption of water from the surrounding environment or from exposure to moisture, which can lead to hydrolysis of the organotin species. The hydrolyzed organotin species in the photoresist solution can then react to form clusters and larger species, which can further oligomerize / polymerize, resulting in the formation of insoluble particles in solution. These insoluble particles can manifest as defects in the coated wafer upon deposition. The compositions described herein can improve the solubility of the hydrolyzed species and thereby reduce the number of insoluble particles and the resulting number of coated wafer defects. Another way to assess this improvement is through dose-to-size measurements related to critical dimensions. The enhanced solubility of unexposed regions of the film in polar solvents can enable more complete removal of unexposed and lightly exposed material, such as near the edges of the pattern. Furthermore, the enhanced solubility of unexposed or lightly exposed resist material can reduce scum and residue between features. Thus, by improving the solubility of intermediate compositions near pattern boundaries and by addressing potential inhomogeneities in the irradiated material, the radiation dose required to achieve the desired feature size can be reduced. Patterned compositions with desirable ether ligands have also been observed to improve radiation-induced pyrolysis, which allows for the removal of cleaved organic species from the irradiated material.

[0028] Regarding imparting solubility in more polar solvents, cyclic ethers, aromatic ethers, fluorinated ethers, and polyethers can provide the necessary ligands for tin patterning compositions. Specifically, cyclic ethers can have the following formulas: [-CR(CR2)nO], where n = 2 to 7, or -(CR2)n-[CR(CR2)mO], where [] represents a cyclic structure, n = 1 to 10, m = 2 to 7, and R is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and, optionally, heteroatoms, and R0 is a bond or a linear or branched hydrocarbon group having 1 to 5 carbon atoms and, optionally, heteroatoms. In the first formula, the cyclic ether is directly bonded to the tin atom, while in the second formula, the cyclic ether is spaced from the tin atom. These two formulas can be combined to form [RROC(CR2)mO], where R0 is a bond or a linear or branched hydrocarbon group having 1 to 5 carbon atoms and, optionally, heteroatoms. When R0 is a bond, the cyclic ether is directly bonded to the Sn atom. The CR2 of the cyclic polyether is substituted with -O-, and the cyclic ether can also be a polycyclic compound having multiple independent or overlapping rings. In some polycyclic ethers, two R groups combine to form a ring structure.

[0029] Aromatic ethers have an aromatic group pendant from the ether, for example -(CR 2) nO-(CR 2) mCR 3, where n = 1 to 10, m = 0 to 9, and R is hydrogen or a hydrocarbon group having 1 to 5 carbon atoms, optionally substituted with a heteroatom, and where one or more H atoms are replaced by an aromatic group -Ar, where Ar can be -C 6H 5, -C 5NH 4, -C 10H 7, -CH 2C 6H 5, -C 6H 4C 6H 5, etc. In an alternative embodiment, the aromatic group can be directly bonded to the ether oxygen of the formula -(CH 2) nO-Ar, exemplified by -CH 2OC 6H 5. With respect to linear (non-cyclic) polyethers, as described above, it may be desirable to space the ether oxygen from the carbon bonded to the Sn atom. Such ligands can be represented by the formula -CR1R2R3 (wherein R1, R2, and R3 are independently H (for no more than two of the three R groups)), or -CR4R5R6 (wherein R4, R5, and R6 are independently H (for no more than two of the three R groups)), or a hydrocarbon group (wherein at least one of R4, R5, and R6 has an ether group, and the hydrocarbon group typically has 1 to 8 carbon atoms). Thus, -CR1R2R3 includes branched structures and groups having two or more ether groups. Suitable polyethers can be linear, branched, and / or cyclic. Polyether ligands can include, for example, -CH2OCH2OCH2, -CH2CH(OCH3), -cyclo(CHCH2OCH2CH2O), and the like. In any of the formulae shown in this paragraph, any H atom may be substituted with a halogen atom (F, Cl, Br, or I) or other heteroatom-based groups (e.g., hydroxyl, amine, cyano, thiol, silyl, ether, ketone, ester, or combinations thereof).

[0030] In yet other embodiments, the desired ligand may include a halogen and an ether bond to provide targeted solubility, potentially enhanced radiation absorption, and desired bonding properties. For embodiments of halogenated ethers represented by the formula R 1OR 0C(R 2R 3)-, R 0 is a bond or a linear or branched hydrocarbon group having 1 to 5 carbon atoms and optionally heteroatoms, R 1 is a hydrocarbon group having 1 to 10 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, and R 2 and R 3 are independently hydrogen, a halogen, or a hydrocarbon group having 1 to 7 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, wherein at least one of R 1, R 2, and R 3 contains a halogen atom.

[0031] As a component of a blended composition for forming a radiation-sensitive coating, radiation sensitivity, development efficiency, defect reduction, and pattern characteristics can be adjusted to achieve desired patterning performance. When a component having oxygen-containing ligands as described in the preceding paragraph is included in a blended precursor composition for forming a radiation-sensitive coating, the inclusion of such a component may be desirable for influencing developer efficiency and corresponding defect reduction. In some embodiments, the precursor solution may include a blend of precursor compounds, wherein the desired precursor component having an ether group in a ligand having a C—Sn bond is an ether precursor in a ratio of about 2 mole percent (mol%) to about 95 mol%. Within these broad ranges of precursor blends, there may be desirable blends having lesser amounts of ether ligands, ranging from about 4 mol% to about 50 mol%, and in other embodiments, from about 5 mol% to about 40 mol%, as well as alternative blends in which the majority of the ether ligands are present, with precursors having ether ligands ranging from about 55 mol% to about 90 mol%, and in still other embodiments, from about 70 mol% to about 85 mol%. Those skilled in the art will recognize that additional ranges of precursor proportions having oxygen-containing ligands within the above-specified ranges are also contemplated and are within the scope of the present disclosure.

[0032] The film-forming ability of organotin compositions containing oxygen heteroatoms within the ether group within the hydrocarbon chain can also be improved compared to the film-forming ability of unsubstituted precursor compositions. The oxygen heteroatoms provide hydrogen bonding sites that enhance intermolecular bonding between species within the organotin oxo / hydroxy coating and improve film homogeneity relative to unsubstituted compositions. Improved homogeneity is often associated with fewer patterning defects, making visual observation and assessment of patterning defects a useful tool for assessing coating uniformity.

[0033] The moiety of the hydrocarbyl ligands in the organotin composition can also play a significant role in the solubility of partially and / or fully hydrolyzed organotin species after coating. Hydrolysis of RSnL3 results in the formation of the known oval dodecamer (RSn)12O14(OH)8 cluster, which exhibits significantly different solubilities depending on the moiety of the R group. For example, when R = tertiary butyl (-C(CH3)3), the resulting dodecamer generally exhibits low solubility, while when R = n-butyl (-(CH2)3CH3), the resulting dodecamer is much more soluble. For organotin compositions with ether groups described herein, the presence of an oxygen atom in the hydrocarbyl ligand improves the solubility of both partially and fully hydrolyzed products, regardless of whether they are prone to cluster formation.

[0034] In some embodiments, pattern defects such as scum and microbridges can be reduced in the presently disclosed compositions relative to unsubstituted organotin compositions. While not wishing to be bound by theory, pattern defects can form due to unintentional radiation exposure in blank / dark areas of the pattern (i.e., areas not intended to be directly irradiated). This radiation exposure can cleave Sn-C bonds and result in the formation of lightly polymerized RSn-O-Sn species in the unintended areas. These lightly polymerized species are believed to be underexposed (i.e., only a small portion of the Sn-C bonds have been cleaved), but can have lower solubility in the developer and can remain after development, manifesting as defects in the pattern. The compositions described herein produce lightly polymerized species with higher solubility and, therefore, can reduce the amount of pattern defects.

[0035] The compositions described herein can be used as precursors for forming radiation-patternable coatings, as well as for converting precursors into other useful compositions, such as compositions with different hydrolyzable ligands or cluster compositions with Sn-O-Sn bonds. As described above, the radiation sensitivity of organotin materials stems from the properties of the Sn-C bond, and therefore it is generally desirable to maintain the Sn-C bond intact during processing from the precursor to the coating. For related embodiments, the hydrolyzable ligand has little effect on photosensitivity (i.e., it does not substantially comprise a radiation-patternable coating) and is generally selected for desired processing, such as further purification, deposition mode, stability, handling, etc., although the hydrolyzable ligand can affect the properties of the hydrolyzed coating with respect to specific structures and densities. Generally, if desired, the hydrolyzable ligand can be hydrolyzed to provide oxo- and / or hydroxy-substituted ligands prior to photopatterning. Some examples of suitable hydrolyzable ligands are -NR', -OR', -CCR', and -CC(SiR'), wherein R' is a hydrocarbon group having 1 to 30 carbon atoms, such as -NMe, -NEt, -OiPr, -OtBu, -OtAmyl, -CC(C6H5) ["PhAc"], -CC(Si(CH3)3) ["TMSA"], etc. The applicant's current commercial products are based on hydrolyzable ligands having the structure -OR'.

[0036] In one embodiment of forming a radiation-patternable coating, an organotin composition having an oxygen heteroatom in the R ligand of RSnL3 can be dissolved in a solvent in the presence of water vapor, coated directly on a substrate to produce a coating, and then further baked or alternatively baked in the presence of water vapor to form a radiation-patternable organotin oxo / hydroxide coating. During the coating deposition and / or pre-patterning baking step, water vapor can be present to effect in-situ hydrolysis, thereby producing a radiation-patternable organotin oxo / hydroxide coating. Blending of various RnSnL4-n compounds wherein n = 0, 1, or 2 (e.g., SnL4, RSnL'3, and R'SnL''3, wherein R and R' are the same or different, and L, L', and L'' are the same or different) in a suitable solvent can provide readily deposited organotin oxo / hydroxide films having the corresponding RnSn compositions.

[0037] In another embodiment, as described in the preceding paragraph, the relatively high vapor pressure and reactivity of many molecular RnSnL4-n compounds enable the use of vapor deposition methods to deposit radiation-patternable organotin oxo / hydroxide coatings. Possible vapor deposition methods include, for example, physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or modifications thereof. For example, one or more gaseous RnSnL4-n compounds can be introduced into a reaction chamber and reacted with a co-precursor, such as HO or its related decomposition products, in the vapor phase or on the substrate surface to produce a radiation-sensitive organotin oxide hydroxide coating. Generally speaking, if the hydrolyzable compound is deposited on the surface via a subsequent hydrolysis reaction, the process can be considered a PVD deposition using in-situ hydrolysis, but if the hydrolysis occurs during a continuous deposition process, it can be considered a CVD process. Similarly, if a hydrolyzable precursor is sequentially adsorbed, chemisorbed, or decomposed on the substrate surface, and the residual film reacts with a second reactive precursor through multiple deposition / reaction cycles to deposit the corresponding organotin oxide hydroxide, it can be considered an ALD process. Advantages of vapor deposition methods can include reduced resist film defect density, improved thickness and composition uniformity, and conformal and sidewall coating of the substrate topography. [Organotin composition containing oxygen heteroatoms]

[0038] A precursor of a radiation-sensitive organotin composition containing an oxygen heteroatom can be represented by the formula R1-OR2SnL3, where R1 is selected from a linear, aromatic, cyclic, branched, or unsaturated hydrocarbyl ligand having 1 to 30 carbon atoms, and is optionally further substituted with O, F, I, Si, Sn, Te, and / or Sb; R2 is a hydrocarbyl ligand having a Sn-C bond and 2 to 5 carbon atoms; and L is a hydrolyzable ligand. In some embodiments, the R1 moiety or the R2 moiety may comprise a linear, branched, or cyclic group having one or more ether groups. In some embodiments, R2 comprises branched carbon atoms, i.e., carbon atoms having one or less C—H bonds. In additional embodiments, R 1 and R 2 form a ring structure such that one or more O atoms are part of a cyclic ether, and R 1-OR 2 can be equivalently written as the ring (-CH[(CH 2) n:oO(CH 2) m:o] o), where Σ o(n:o+m:o+1)+2 is the ring size, where n+m ≥ 1 and o ≥ 1, and where m and n can vary depending on the value of o. In embodiments where a cyclic ether is present, an alkyl moiety can be present between the cyclic ether and the Sn atom and can be represented by the formula (-RL[(CH 2) n:oO(CH 2) m:o] o), where RL is a hydrocarbyl ligand having a Sn-C bond and 2 to 10 carbon atoms. The types of desired ether ligands are described in detail throughout the specification and directly supplement this specific discussion.

[0039] Some specific examples of structures represented by the formula R 1-OR 2Sn are shown below: .

[0040] The synthesis of the oxygen-heteroatom organotin compositions disclosed herein can be accomplished by methods previously described by the applicant (e.g., methods described in published U.S. Patent Application No. 2019-0315781, entitled "Monoalkyl Tin Compounds With Low Polyalkyl Contamination, Their Compositions And Methods," by Edson et al., and the aforementioned '192 application, both of which are incorporated herein by reference). The choice of synthetic technique can be based on practical considerations, such as the purity, yield, process ease, and availability of convenient starting materials obtained via different routes. For example, the desired results have been achieved for the general synthesis of monoalkyltin trialkylamides, where the alkylating agent can be a Grignard reagent, a diorganozinc reagent, or a monoorganozinc amide. These syntheses can directly produce monoalkyltin triamides with low polyalkyl contaminants, which can be used to form resists or can be further purified to further reduce contaminant levels. In another method developed by the applicant, the alkylating agent is an alkyl halide, which reacts with a tin composition complexed with an alkali metal ion, an alkaline metal ion, and / or a pseudoalkaline metal ion. Unless otherwise noted, the synthesis process and storage of the composition are carried out in isolation from the ambient atmosphere, such as in a glove box, a sealed system, a sealed container, etc.

[0041] In some embodiments, a Grignard-type reaction can be used to synthesize the desired R 1-OR 2SnL 3 compound. The general Grignard-type reaction to form R 1-OR 2SnL 3 can be represented by the following reaction: RMgX + SnL 4à RSnL 3.

[0042] In some embodiments, an oxidative stannylation reaction may be a desirable route to produce the desired R1-OR2SnL3 compound, as further described in the aforementioned '192 application. In a typical stannylation reaction, a tin dihalide (e.g., SnCl2) is first reacted with an organic base (R'M, such as R'Li) compound to form an alkali metal stanamide or alkali metal tin acetylide, which is then reacted with an organic halide containing the desired R group attached to the tin atom. The synthesis can be represented by the following reaction: 3 R'M + 3 HL+ SnX 2à MSnL 3 MSnL 3+ RX à RSnL 3.

[0043] In the above reaction, the organotin RSnL3 product typically contains an amide or acetylide as the hydrolyzable ligand L. In some embodiments, the hydrolyzable ligand L is an amide, such as -NMe2, -NEt2, or -NiPr2. Due to their high vapor pressure and reactivity, amides are particularly suitable as hydrolyzable ligands for steam treatment of organotin oxide hydroxide coatings and for conversion to the corresponding organotin alkoxide. In some embodiments, the hydrolyzable ligand is an acetylide. Organotin acetylide (RSn(CCR')3) is particularly suitable as a precursor for preparing the corresponding organotin alkoxide, and particularly useful R' groups are trialkylsilyl groups, such as -Si(CH3)3 ["TMSA"], -Si(CH2CH3)3 ["TMSA"], and phenyl ("PhAc"). In general, efficient conversion of organotin acetylides to the corresponding organotin alkoxides depends on the nature of the alcohol, R group, and R' group and can be achieved by routine experimentation.

[0044] In some embodiments, the hydrolyzable ligand of the radiation-patternable precursor composition is an alkoxide. Alkoxides are particularly suitable as hydrolyzable ligands for processing oxide hydroxide coatings (either solution-processed or vapor-phase processed) due to their storage stability, hydrolytic susceptibility, relatively mild hydrolysis products (e.g., alcohols), and vapor pressures suitable for vapor deposition. The conversion of organotin amides and acetylides to organotin alkoxides can typically be achieved by alcholysis as described in the following reaction: RSn(NR' 2) 3+ 3 R''OH → RSn(OR'') 3+ 3HNR' 2, or RSn(CCR') 3+ 3 R''OH → RSn(OR'') 3+ 3HCCR', wherein R' and R" are the same or different and are typically alkyl groups having ≤ 10 carbon atoms. Particularly suitable R' and R" groups are methyl, ethyl, propyl, butyl, pentyl (amyl), phenyl, and, where applicable, their respective isomers, such as tert-pentyl.

[0045] Once produced, the R1-OR2SnL3 compound can be further purified by any suitable method (e.g., distillation) to provide a suitably pure composition. Purification depends on the nature of the compound but generally involves separating the desired product from byproducts and potentially any unreacted reagents. Purification may also involve removing any volatile compounds, including solvents, from the product mixture by drying or exposure to vacuum. For products with significant vapor pressure, it may be desirable to purify the product by vacuum distillation or, if necessary, by fractional distillation designed to achieve high purity. See published U.S. patent application 2020 / 241413 to Clark et al. (hereinafter referred to as the '413 application), entitled "Monoalkyl Tin Trialkoxides and / or Monoalkyl Tin Triamides With Low Metal Contamination and / or Particulate Contamination and Corresponding Methods," which is incorporated herein by reference.

[0046] The product, with or without prior purification, can also be reacted to form a derivative, such as an organotin trialkoxide, which can be further purified by the techniques described above and other means known in the art. After preparing the trialkoxide composition, further purification of the composition can be performed, if desired. In some embodiments, fractionation methods such as those described in U.S. Patent No. 10,787,466 to Edson et al., entitled "Monoalkyltin compounds with low polyalkyl contamination, their compositions and methods," which is incorporated herein by reference, can be used.

[0047] Purity can be assessed by the presence of undesirable impurities (e.g., metals other than Sn or undesirable byproducts). For semiconductor applications where nanoscale properties may be affected by small amounts of impurities (e.g., non-Sn trace metals), high purity of the organotin compound is desirable. Metal purity can generally be assessed by any suitable means known in the art, such as mass spectrometry, including inductively coupled plasma mass spectroscopy (ICP-MS) and similar techniques. In some embodiments, the R1-OR2SnL3 compound may have a metal purity greater than about 99.99% (<100 ppm non-Sn metal), in other embodiments greater than about 99.999% (<10 ppm non-Sn metal), in still other embodiments greater than about 99.9999% (<1 ppm non-Sn metal), and in still other embodiments greater than about 99.99999% (<0.1 ppm non-Sn metal). For some applications, it may be desirable for the organotin compound to have a high purity by mass relative to other Sn compounds (i.e., impurities). In some cases, the synthesis of the organotin compound may produce byproduct impurities. In some cases, the synthesis of organotin compounds can produce a mixture of tin-containing reaction products (e.g., a majority of the target monoalkyltin compound and minor amounts of dialkyltin and / or inorganic tin impurities present in the product), and the separation and purification of a single phase of monoalkyltin can be difficult. Nuclear magnetic resonance (NMR) and gas chromatography mass spectrometry (GC-MS) techniques can be used to analyze the purity of organotin compounds (e.g., the oxygen-heteroatom organotin compositions disclosed herein). In some embodiments, the R1-OR2SnL3 compound can have a purity of at least about 90% by mass, in other embodiments at least about 95% by mass, in still other embodiments at least about 99% by mass, and in other embodiments at least about 99.9% by mass. [Solution composition]

[0048] The organotin compounds described herein can be used as precursors for forming radiation-patternable coatings for semiconductor lithography applications. Because organotin compounds are highly absorptive at EUV wavelengths and exhibit high etch resistance, they are desirable for producing smooth, uniform, and dense coatings, enabling high-resolution patterning using EUV lithography. In some embodiments, the organotin compounds described herein can be dissolved in a solvent to form an organotin photoresist solution, enabling deposition of the solution into a radiation-patternable coating.

[0049] Suitable solvents include those in which the organotin photosensitive composition is suitably soluble, but may also be selected based on their physical properties (e.g., flammability, viscosity, toxicity, or volatility) depending on the intended processing method. Further considerations in selecting a suitable solvent may include potential interactions with partially and / or completely hydrolyzed organotin species, such as mitigating undesirable particle formation and agglomeration. In some embodiments, while not wishing to be bound by theory, primary alcohols may be beneficial in the solvent composition due to their ability to retard hydrolysis and to better interact with and dissolve organotin hydrolysis and condensation products. Other considerations for a suitable solvent may include cost and potential interactions with other processing materials. Some examples of suitable solvents include alcohols (e.g., 4-methyl-2-pentanol, 1-butanol, cyclohexanol, n-propanol, isopropanol, n-butanol, isobutanol, 2-isopropoxyethanol), esters (e.g., ethyl acetate, propylene glycol monomethyl ether acetate, ethyl lactate), ethers (e.g., propylene glycol monomethyl ether), ketones (e.g., 2-heptanone, cyclopentanone, cyclohexanone, 1-butanone, 4-methyl-2-pentanone), mixtures thereof, etc. One of ordinary skill in the art will appreciate that other suitable solvents not specifically listed are also contemplated.

[0050] The composition of the organotin solution can be conveniently determined based on the molar concentration of the tin ions. Generally speaking, the organotin solution typically contains from about 0.0025 M to about 1.4 M tin cations, in some embodiments from about 0.004 M to about 1 M tin cations, in still other embodiments from about 0.005 M to about 0.75 M tin cations, in some embodiments from about 0.01 M to about 1 M tin cations, and in additional embodiments from about 0.01 M to about 0.5 M tin cations. One of ordinary skill in the art will recognize that additional concentration ranges and values ​​within the above-specified ranges are also contemplated and within the scope of the present disclosure.

[0051] In some embodiments, the oxygen-heteroatom-ether organotin composition may be present in a blended solution with one or more other monoalkyltin compounds and / or other organotin compositions (e.g., RnSnL4-n and its hydrolysis products), where n is 0, 1, or 2, and R is another ligand having the same overall structure as R1-OR2 as defined above, or R is a linear, branched, cyclic, aromatic, and / or substituted hydrocarbon group having a Sn-C bond. Such a blended solution (e.g., aR'SnL3+(1-a)R"nSnL'4-n, where "a" is the ratio of the original ether-containing organotin compound) can be adjusted to optimize various performance considerations, such as solution stability, coating uniformity, and patterning performance. A blend composition can be achieved by combining two or more organotin compositions (e.g., RnSnL4-n, where L is a hydrolyzable ligand) in the presence or absence of a solvent. For example, pure RSnL3 can be combined with pure R'SNL'3 to form a blend precursor. If desired, the blend composition can be diluted in a solvent. Alternatively, each organotin composition can be diluted in a desired solvent to form a different organotin solution, and each organotin solution can then be combined to form the blend solution. Generally speaking, the hydrolyzable ligand can be the same or different for each organotin component in the overall blend composition. In some embodiments, the oxygen-heteroatom-ether composition can comprise at least 1 mol% Sn of the blended solution, in further embodiments at least 10 mol% Sn of the blended solution, in further embodiments at least 25 mol% Sn of the blended solution, and in further embodiments at least 75 mol% Sn of the blended solution. Additional mole % ranges for the oxygen-heteroatom organotin composition are contemplated and are within the scope of the present disclosure.

[0052] In some embodiments, the organotin photoresist solution may be filtered to eliminate or reduce particulate contamination. Clark et al. describe suitable filtering methods in U.S. Patent No. 11,498,934, entitled "Monoalkyl Tin Trialkoxides And / Or Monoalkyl Tin Triamides With Low Particulate Contamination and Corresponding Methods," which is incorporated herein by reference.

[0053] In some embodiments, the organotin photoresist solution can be partially hydrolyzed in solution (i.e., controlled in-situ hydrolysis) by adding a controlled amount of water to the organotin photoresist solution composition. Suitable methods for adding controlled amounts of water to the organotin photoresist solution are described in U.S. Patent No. 11,300,876, entitled "Stable Solutions of Monoalkyl Tin Alkoxides and Their Hydrolysis and Condensation Products," by Jiang et al. (hereinafter referred to as the '876 patent), which is incorporated herein by reference. While not wishing to be bound by theory, it is believed that by allowing a certain degree of hydrolysis and condensation to occur prior to deposition, controlled in-situ hydrolysis can achieve a distribution and concentration of clusters and similar species that is more favorable for solution-based deposition (e.g., spin coating). Thus, different combinations of water concentration and solvent in the organotin photoresist solution can be adjusted to provide a balance between solution stability and film quality, as taught in the '876 patent. Precursor solution stability can be assessed by visually observing the solution for particle formation and / or gelation over time. Commercial precursor solutions typically have a shelf life of more than one month. [Radiation patternable coating]

[0054] Radiation-patternable coatings can be formed by depositing a photosensitive composition on a selected substrate and then processing it. The deposition of radiation-patternable coatings can be achieved by various methods known to those skilled in the art.

[0055] It is generally desirable to perform the irradiation step for patterning after removing any hydrolyzable ligands by hydrolysis and forming an oxo-hydroxyl network. Therefore, the stable precursor solution is appropriately transitioned between deposition and irradiation. Deposition of radiation-sensitive organotin precursor compositions into radiation-patternable coatings is typically achieved via a hydrolysis process and a condensation process. For example, solution deposition of radiation-patternable organotin coatings is described in the aforementioned Meyers reference. Vapor deposition techniques using hydrolysis / condensation-based reactions are also described in Wu et al., published PCT patent application No. WO 2019 / 217749, entitled "Methods for Making EUV Patternable Hard Masks," incorporated herein by reference, and the aforementioned '618 patent. In any case, the radiation-sensitive organotin composition can be significantly converted into an organotin hydroxide oxide, in which the radiation-sensitive organic ligand having Sn-C bonds to the Sn atoms is incorporated into a loosely connected network of Sn-O-Sn and Sn-OH bonds. For the organotin compositions described herein with oxygen heteroatoms, the radiation-patternable coating can have additional intermolecular and / or network bonding. The presence of oxygen atoms in the hydrocarbyl chain can enable intermolecular hydrogen bonding and / or polar interactions within the organotin oxo / hydroxyl network.

[0056] If solution deposition is desired, a particularly useful solution deposition method is spin coating. Spin coating is well known in the art and is particularly useful for photoresist processing in semiconductor manufacturing. In a typical spin coating process, a photoresist solution is applied to the surface of a substrate (such as a silicon wafer), which is rapidly spun to form a coating. During the spin coating process, the hydrolyzable ligands of the organotin precursor composition react with water in the environment, undergoing significant hydrolysis and condensation, resulting in a coating on the substrate comprising Sn-O-Sn and Sn-OH networks, as well as radiation-sensitive Sn-C bonds. In some embodiments, the improved photoresist precursor solution is spin-coated at a spin speed of 500 rpm to 3000 rpm. The rpm used is not particularly limited but is generally suitable for producing the desired coating thickness. Generally speaking, for a given photoresist solution, slower spin speeds produce greater coating thicknesses than faster spin speeds. Those skilled in the art will understand the relationship between spin speed and coating thickness.

[0057] The thickness of the radiation-patternable coating can vary depending on the desired process. For use in single-patterning EUV lithography, the coating thickness is generally selected to produce patterns with low defectivity and pattern reproducibility. In some embodiments, a suitable coating thickness may be between 1 nm and 100 nm, in some embodiments from about 1 nm to about 75 nm, in still other embodiments from about 1.5 nm to 50 nm, and in still other embodiments from about 2 nm to 25 nm. Those skilled in the art will appreciate that additional ranges of coating thickness are contemplated and fall within the scope of the present disclosure.

[0058] In other embodiments, the radiation-patternable coating can be formed by various vapor deposition methods, such as atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etc. In typical vapor deposition techniques, one or more metal-containing precursors are reacted with one or more small molecule vapor-phase reagents (e.g., H2O, H2O2, O3, O2, or CH3OH), which serve as sources of O and H to produce oxides and oxide hydroxides. Thus, the hydrolyzable compound can be directly deposited as the corresponding alkyltin oxide hydroxide coating via hydrolysis during vapor deposition, which can then be appropriately patterned.

[0059] In CVD processes, two or more reactant gases are typically mixed within a chamber near the substrate surface. Therefore, sufficient stability can be engineered into the reaction conditions to control undesirable gas-phase reactions and nucleation. ALD precursors, introduced separately and sequentially into the reaction chamber, typically react with chemisorbed co-precursors or decomposition products that have permeated the substrate surface. Desirable characteristics of an RSnX3 precursor include, for example, sufficient volatility for vapor-phase transport within the system, thermal stability to prevent premature decomposition, and appropriate reactivity with the co-precursor to produce the desired product under the specified process conditions. In some embodiments, the RSnL3 precursor may comprise an alkoxide (e.g., L = OR) or a dialkylamide (e.g., L = NR2). The pressure and temperature within the reaction chamber can be selected to control the reaction process.

[0060] The coating thickness of radiation-patternable coatings prepared by vapor deposition techniques can generally be controlled by appropriately selecting the reaction time or number of cycles in the process. The thickness of the radiation-patternable coating can vary depending on the desired process. For use in single-patterning EUV lithography, the coating thickness is generally selected to produce patterns with low defects and pattern reproducibility. In some embodiments, a suitable coating thickness may be between 1 nm and 100 nm, in some embodiments from about 1 nm to about 75 nm, in still other embodiments from about 1.5 nm to 50 nm, and in still other embodiments from about 2 nm to 25 nm. Those skilled in the art will appreciate that additional ranges of coating thickness are contemplated and are within the scope of the present disclosure.

[0061] The substrate generally has a surface onto which a coating material can be deposited, and it may comprise multiple layers, with the surface being associated with the uppermost layer. The substrate is not particularly limited and may comprise any reasonable material, such as silicon, silicon dioxide, other inorganic materials (e.g., ceramics), and polymeric materials.

[0062] After the radiation-patternable coating is deposited and formed, further processing may be performed prior to radiation exposure. In some embodiments, the coating may be heated to a temperature between 30°C and 300°C, in further embodiments between 50°C and 200°C, and in yet further embodiments between 80°C and 150°C. Heating may be performed for about 10 seconds to about 10 minutes in some embodiments, for about 30 seconds to about 5 minutes in further embodiments, and for about 45 seconds to about 2 minutes in yet further embodiments. Additional ranges of temperatures and heating durations within the above-specified ranges are contemplated and are within the scope of the present disclosure. [Patterning of Composition]

[0063] The radiation can typically be directed toward the coated substrate through a mask, or the radiation beam can be controllably scanned across the substrate. Generally, the radiation can include electromagnetic radiation, an electron beam (beta radiation), or other suitable radiation. Generally, the electromagnetic radiation can have a desired wavelength or wavelength range, such as visible radiation, ultraviolet radiation, or X-ray radiation. The resolution of the radiation pattern that can be achieved generally depends on the wavelength of the radiation, and higher-resolution patterns can generally be achieved with shorter-wavelength radiation. Therefore, it may be desirable to use ultraviolet light, X-ray radiation, or an electron beam to achieve particularly high-resolution patterns.

[0064] According to the international standard ISO 21348 (2007), which is incorporated herein by reference, ultraviolet light extends between wavelengths greater than or equal to 100 nm and less than 400 nm. Krypton fluoride lasers can be used as sources of 248 nm ultraviolet light. According to accepted standards, the ultraviolet range can be subdivided in several ways, such as extreme ultraviolet (EUV), which extends from greater than or equal to 10 nm to less than 121 nm, and far ultraviolet (FUV), which extends from greater than or equal to 122 nm to less than 200 nm. 193 nm lines from argon fluoride lasers can be used as radiation sources in FUV. EUV light at 13.5 nm has been used in lithography and is produced by Xe or Sn plasma sources excited by high-energy lasers or discharge pulses. Soft X-rays can be defined as those extending from greater than or equal to 0.1 nm to less than 10 nm.

[0065] During exposure to radiation such as ultraviolet (UV), extreme ultraviolet (EUV), and electron beams, and during subsequent processing, the Sn-C cleaves, forming a further condensed and more hydrophilic oxide-hydroxide network. As the relative concentration of organic ligands in the exposed areas decreases, the polarity of the exposed areas increases, and the hydrophilicity of the exposed areas increases.

[0066] Depending on the design of the coating material, a significant contrast in material properties can be observed between irradiated areas with condensed coating material and unirradiated areas of the coating material where Sn-C bonds remain substantially intact. For embodiments in which a post-irradiation heat treatment is used, the post-irradiation heat treatment can be conducted at a temperature of from about 45°C to about 300°C, in additional embodiments from about 50°C to about 250°C, and in still other embodiments from about 75°C to about 200°C. Post-exposure heating can generally be conducted for at least about 0.1 minute, in further embodiments from about 0.5 minute to about 30 minutes, and in still other embodiments from about 0.75 minute to about 10 minutes. Those skilled in the art will recognize that additional post-irradiation heating temperature and time ranges within the above-specified ranges are contemplated and are within the scope of the present disclosure. The post-irradiation bake step can help remove radiation-scattered organic groups (typically R-), which may react with other groups to form stable species that leave the coating. The loss of organic matter in the coating can be confirmed by spectroscopic measurements (e.g., Fourier transform infrared spectroscopy, which measures carbon vibrations). This high contrast in material properties further facilitates the formation of high-resolution lines with smooth edges in the pattern after development, as described in the following paragraphs.

[0067] In general, organotin photoresists can be developed in either negative- or positive-tone modes, depending on the chemical composition of the developer. However, to improve specific patterning formats, certain ligands may be more optimally suited for specific patterning formats. Many ether-containing ligands are best suited for negative-tone patterning. The choice of developer can be influenced by solubility parameters relative to irradiated and unirradiated coating materials, as well as the developer's volatility, flammability, toxicity, viscosity, and potential chemical interactions with other process materials. As demonstrated in the Examples, the organotin coating compositions described herein containing oxygen heteroatoms can exhibit significantly different developer solubility compared to unsubstituted organotin compositions. Generally, monoalkyltin compositions exhibit negative-tone behavior in organic solvents due to the significant nonpolarity / hydrophobicity of the alkyl ligands in the unexposed regions of the coating, thereby imparting solubility to these regions. Similarly, irradiated regions of coatings lacking alkyl ligands and richer in Sn-OH / Sn-O-Sn bonds exhibit increased polarity / hydrophilicity and, therefore, increased solubility in polar and / or acidic and basic solvents. As described above, organotin compounds with oxygen heteroatoms can exhibit increased polarity and / or hydrogen bonding properties and, therefore, increased interaction between the oxygen heteroatoms within the hydrocarbyl ligands and polar developer solvents. The ability to effectively utilize more polar solvents allows for the efficient formation of patterns with fewer defects and improved edges. Similar improvements can be achieved for dry development by selecting development conditions.

[0068] For negative-tone imaging, the developer can generally be an organic solvent, such as the solvent used to form the precursor solution. Generally, the choice of developer can be influenced by the solubility parameters of the irradiated and unirradiated coating materials, as well as the developer's volatility, flammability, toxicity, viscosity, and potential chemical interactions with other process materials. Specifically, suitable developers include, for example, alcohols (e.g., 4-methyl-2-pentanol, 1-butanol, isopropyl alcohol, 1-propanol, methanol), ethyl lactate, ethers (e.g., tetrahydrofuran, dioxane, anisole), ketones (pentanone, hexanone, 2-heptanone, octanone), and the like. Development can be performed for about 5 seconds to about 30 minutes, in some embodiments, about 8 seconds to about 15 minutes, and in yet other embodiments, about 10 seconds to about 10 minutes. Those skilled in the art will recognize that additional ranges within the explicit ranges above are contemplated and fall within the scope of the present disclosure. In addition to the main developer composition, the developer may include additional additive compositions to facilitate the development process. Suitable additives may include, for example, viscosity modifiers, solubilizing agents, or other processing aids. If optional additives are present, the developer may include no more than about 10% by weight of additives, and in some embodiments no more than about 5% by weight of additives. One of ordinary skill in the art will recognize that concentration ranges of additional additives within the above-specified ranges are contemplated and are within the scope of the present disclosure. Developer blends and additives are further described in published U.S. patent application 2020 / 0326627 to Jiang et al., entitled "Organometallic Photoresist Developer Compositions and Processing Methods," which is incorporated herein by reference.

[0069] In some embodiments, solvent-free (dry) development can be performed using an appropriate thermal or plasma development process, such as those described in published PCT patent application WO 2020 / 264158, entitled "Photoresist Development With Halide Chemistries," by Tan et al., which is incorporated herein by reference. For organotin photoresist coatings, dry development can be performed using a halogen-containing plasma and gas (e.g., HBr and BCl₃). In some cases, dry development can offer advantages over wet development, such as reduced pattern collapse, reduced scumming, and finer control over developer composition (i.e., plasma and / or etching gas).

[0070] After the development step is complete, the coating material may be heat-treated to further condense the material and further dehydrate, densify, or remove residual developer from the material. This heat treatment may be particularly desirable for embodiments in which the oxide coating material is incorporated into a final device, but may also be desirable for some embodiments in which the coating material is used as a photoresist and ultimately removed if it is desired to stabilize the coating material to facilitate further patterning. Specifically, the patterned coating material may be baked under conditions that result in the patterned coating material exhibiting a desired level of etch selectivity. In some embodiments, the patterned coating material may be heated to a temperature of about 100°C to about 600°C, in other embodiments from about 175°C to about 500°C, and in additional embodiments from about 200°C to about 400°C. Heating may be performed for at least about 1 minute, in other embodiments from about 2 minutes to about 1 hour, and in still other embodiments from about 2.5 minutes to about 25 minutes. Heating can be performed in air, vacuum, or an inert gas environment (e.g., Ar or N 2). Those skilled in the art will recognize that additional temperature and time ranges for thermal treatment within the above-specified ranges are contemplated and fall within the scope of the present disclosure. Similarly, non-thermal treatments including blanket UV exposure or exposure to an oxidizing plasma, such as O 2, can be used for similar purposes.

[0071] Wafer throughput is a substantial limiting factor for EUV lithography implementation in high-volume semiconductor manufacturing and is directly related to the dose required to pattern a given feature. However, despite the availability of chemical strategies to reduce imaging dose, for EUV resists with feature sizes and pitches <50 nm, a negative correlation between the imaging dose required to print the target feature and feature size uniformity (e.g., LWR) is often observed, limiting final device operability and wafer yield. Patterning capability can be expressed in terms of a dose-to-gel value. Imaging dose requirements can be assessed by forming an array of exposed pads, where the exposure time is stepped between pads to vary the exposure dose. The film can then be developed, and the remaining resist thickness for all pads can be assessed, for example, using spectroscopic ellipsometry. The measured thickness can be normalized to the maximum measured resist thickness and plotted against the logarithm of the exposure dose to form a characteristic curve. The maximum slope of the normalized thickness versus log dose curve is defined as the resist contrast (γ), and the dose value at which the tangent drawn through this point equals 1 is defined as the resist gel dose (Dg). D0 corresponds to the onset dose, the initial increase in film thickness for negative resists. Thus, the commonly used parameters for resist characterization can be approximated by Mack, C. (Fundamentals of Photolithography, John Wiley & Sons, Chichester, UK; pp. 271-272, 2007, incorporated herein by reference).

[0072] Automated imaging equipment can be used to evaluate patterned structures, typically using a scanning electron microscope (SEM) imager. For example, certain commercial critical dimension scanning electron microscope (CD-SEM) instruments can measure critical line dimensions (line widths) and also assess defects such as microbridging. In some embodiments, using equivalent development, coating formation, and irradiation, patterning with improved development based on the resist engineering described herein can result in an increase in critical dimension. From another perspective, the concept of critical dimension can be expressed as a dose-to-size value, which is the radiation dose required to achieve a specific feature size. Therefore, an increase in critical dimension corresponds to a decrease in dose-to-size value, consistent with the ability to achieve specific patterning goals using lower doses. As demonstrated, for the blended resist, a dose-to-size based on a 16 nm critical dimension can be achieved using a dose of less than 30 mJ / cm². [Example] [Example] [1] [:] [R , 1 , OR , 2 , -Sn-L , 3, ] [Synthesis of Compounds]

[0073] The following examples include the synthesis and NMR characterization of R 1 OR 2 SnL 3 compounds having hydrolyzable ligand groups L, including tris(trimethylsilyl acetylide) ((TMSA) 3 ) and tris(tert-butyl oxide) ((OtBu) 3 ). The R 1OR 2- group includes CH 3OCH 3CH- or methoxyethyl (MOE), CH 3OCH 2- or methoxymethyl (MOM), CH 3O(CH 3) 2C- or methoxypropyl (MOP), [(CH 2) 2OCH 2CH]- or 3-tetrahydrofurfuryl (THF), [(CH 2) 2O(CH 2) 2CH]- or 4-tetrahydropyranyl (THP), [(CH 2) 2O(CH 2) 2C(CH 3)]- or 4-methyl-4-tetrahydropyranyl (mTHP), methyl-tert-butyl ether or (CH 3) 3COCH 2-(MTBE), methyl phenyl ether or C 6H 5OCH 2-(MPE), dimethoxyethyl or (CH 3 O) 2CHCH 2-(DME), and trifluoroethoxymethyl or CF 3CH 2OCH 2-(FET). Except for the secondary synthesis using a Grignard reagent as described below, the synthesis reactions were carried out using tin oxide alkylation reactions. [(CH , 3, OCH(CH , 3, )Sn(CC(SiCH , 3, )) , 3, ] [、] [MOE-Sn-(TMSA) , 3, ] [Synthesis]

[0074] Ethynyltrimethylsilane (3.1 equivalents) and diethyl ether (1.5 mL / eq) were added to a vacuum-purged reaction vessel equipped with a thermometer, stirrer, and addition funnel. The solution was cooled to <0°C, and n-butyllithium (2.0 M in diethyl ether, 3.0 equivalents) was slowly added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred for 30 minutes, and then tin(II) chloride (1 M in THF, 1.0 equivalents) was added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred at 20°C for 2 hours. The internal temperature was then allowed to reach <0°C, and 1-chloro-1-methoxyethane (1.1 equivalents) was added, maintaining the internal temperature below 10°C. The solution was stirred for an additional 30 minutes, after which the volatiles were removed under vacuum. The solid was washed with pentane and filtered. Volatiles were removed under vacuum, and recrystallization was performed from hexane (approximately 1 mL / 1 g of product) at -20°C to provide MOE-Sn-(TMSA) 3 as a crystalline solid. The 1H and 119Sn NMR spectra of MOE-Sn-(TMSA) 3 in benzene-d 6 are shown in Figures 1 and 2, respectively. The spectrum shows the following chemical shifts: 1H NMR (C 6D 6) δ 0.1 (s, 27H, CH 3), δ 1.7 (d, 3H, CH 3), δ 3.3 (s, 3H, CH 3), δ 3.9 (q, 1H, CH); 119Sn NMR (C 6D 6) δ -323. [ , , ] [MOE-Sn-(TMSA) , 3, ] [Convert to] [(CH , 3, OCH(CH , 3, )Sn(OtBu) , 3, ] [、] [MOE-Sn-(OtBu) , 3, ]

[0075] MOE-Sn-(TMSA) 3 and 2% Cu(OtBu) were placed in an inert flask with a stir bar. Tert-butyl alcohol (10 equivalents) and triethylamine (10 equivalents) were added, and the volatiles were slowly removed to yield a viscous liquid. The 1H and 119Sn NMR spectra of MOE-Sn-(OtBu) 3 in benzene-d 6 are shown in Figures 3 and 4, respectively. The spectrum shows the following chemical shifts: 1H NMR (C 6D 6) δ 1.3 (s, 27H, CH 3), δ 1.5 (d, 3H, CH 3), δ 3.3 (s, 3H, CH 3), δ 3.9 (q, 1H, CH); 119Sn NMR (C 6D 6) δ -271. [((CH , 3, ) , 2, COCH , 3, Sn(CC(SiCH , 3, )) , 3, ] [、] [MOP-Sn-(TMSA) , 3, ] [Synthesis]

[0076] Ethynyltrimethylsilane (3.1 equivalents) and diethyl ether (1.5 mL / equivalent) were added to a vacuum-purged reaction vessel equipped with a thermometer, stirrer, and addition funnel. The solution was cooled to <0°C, and n-butyllithium (2.0 M in diethyl ether, 3.0 equivalents) was slowly added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred for 30 minutes, and then tin(II) chloride (1 M in THF, 1.0 equivalents) was added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred at 20°C for 2 hours. The internal temperature was then allowed to reach <0°C, and 2-chloro-2-methoxypropane (1.1 equivalents) was added, maintaining the internal temperature below 10°C. The solution was stirred for an additional 30 minutes, after which the volatiles were removed under vacuum. The solid was washed with pentane and filtered. Volatiles were removed under vacuum, and recrystallization was performed from hexane (approximately 1 mL / 1 g of product) at -20°C to provide MOP-Sn-(TMSA) 3 as a crystalline solid. The 1H and 119Sn NMR spectra of MOP-Sn-(TMSA) 3 in benzene-d 6 are shown in Figures 5 and 6, respectively. The spectra showed the following chemical shifts: 1H NMR (C 6D 6) δ 0.0 (s, 27H, CH 3), δ 1.6 (s, 6H, CH 3), δ 3.3 (s, 3H, CH 3); 119Sn NMR (C 6D 6) δ -315. [Synthesized using Grignard reagent] [THP-Sn-(] [Dimethylamino] [) , 3, ] [and converted to] [THP-Sn-(OtBu) , 3, ]

[0077] Diethyl ether (1.5 mL / equiv) and tetrakis(dimethylamino)tin (1 equiv) were added to a vacuum-purged reaction vessel equipped with a thermometer, stirrer, and addition funnel, and the vessel was cooled to -20°C. Tetrahydropyranylmagnesium bromide (1.0 equiv in THF) was added dropwise over 1 hour. The solution was allowed to warm overnight and then filtered to remove the precipitate. The filtrate was then concentrated, and the volatiles were removed in vacuo to yield THP-Sn-(dimethylamino) 3 as a liquid. A sample of this material was taken and analyzed by NMR.

[0078] The conversion of THP-Sn-(dimethylamino) 3 to THP-Sn-(OtBu) 3 was completed by opening the container containing THP-Sn-(dimethylamino) 3 to a bubbler and slowly adding tert-butanol (1 M / 3.5 equivalents) in pentane. The solution was then distilled to produce a viscous liquid. The 1H and 119Sn NMR spectra of THP-Sn-(OtBu) 3 in benzene-d 6 are shown in Figures 7 and 8, respectively. The spectrum showed the following chemical shifts: 1H NMR (C 6D 6) δ 1.4 (s, 27H, CH 3), δ 1.7 (m, 1H, CH), δ 1.9 (m, 4H, CH 2), δ 3.2 (m, 2H, CH 2), δ 3.8 (m, 2H, CH 2); 119Sn NMR (C 6D 6) δ -231. [Synthesized using Grignard reagent] [mTHP-Sn-(OtBu) , 3, ]

[0079] 4-Bromo-4-methyltetrahydropyranylmagnesium bromide (11.2 mmol) in THF (50 mL) was slowly added to a reaction vessel containing tetrakis(dimethylamino)stannane (3.3 g, 11.2 mmol) at -20°C and allowed to warm to room temperature over 12 hours. After 12 hours, the reaction mixture was filtered and the solvent removed in vacuo. The contents were recrystallized from n-octane and converted to mTHP-Sn-(OtBu) 3 by adding 3.25 equivalents of tert-butyl alcohol. The product was distilled under dynamic vacuum and further purified by fractional distillation. [THF-Sn-(OtBu) , 3, ] [Synthesis]

[0080] n-Butyllithium (1.03 mL, 2.53 mmol, 2.45 M in hexane) was added to a cold solution (-50°C) of trimethylsilylacetylene (0.248 g, 2.53 mmol) in diethyl ether (4 mL). After several minutes, a slurry of tin(II) chloride (0.160 g, 0.845 mmol) in THF (4 mL) was added. The contents were warmed to 0°C and stirred for 2 hours. The flask was cooled to -50°C again and 3-iodotetrahydrofuran (0.167 g, 0.845 mmol) was added. The resulting reaction mixture was allowed to warm to room temperature over 16 hours, at which point the solvent was removed in vacuo. After removal of the solvent, the contents were recrystallized from pentane and converted to THF-Sn-(OtBu) 3 using excess 5 M triethylamine / tert-butanol, which was then further purified by fractional distillation. [synthesis] [(CH , 3, ) , 3, O(CH , 2, )Sn(CC(SiCH , 3, )) , 3, ] [、] [MTBE-Sn-(TMSA) , 3, ] [and converted to] [(CH , 3, ) , 3, O(CH , 2, )Sn(OtBu) , 3, ] [、] [MTBE-Sn-(OtBu) , 3, ]

[0081] Ethynyltrimethylsilane (3.1 equivalents) and diethyl ether (1.5 ml / equivalent) were added to a vacuum-purged reaction vessel equipped with a thermometer, stirrer, and addition funnel. The solution was cooled to <0°C, and n-butyllithium (2.0 M in diethyl ether, 3.0 equivalents) was slowly added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred for 30 minutes, and then tin(II) chloride (1 M in THF, 1.0 equivalents) was added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred at 20°C for 2 hours. The internal temperature was then allowed to reach <0°C, and 2-chloromethoxy-2-methylpropane (1.1 equivalents) was added, maintaining the internal temperature below 10°C. The solution was stirred for an additional 30 minutes, after which the volatiles were removed under vacuum. The solid was washed with pentane and filtered. Volatiles were removed under vacuum, and recrystallization was performed from hexane (approximately 1 mL / 1 g of product) at -20°C to provide MTBE-Sn-(TMSA) 3 as a crystalline solid. The 1H and 119Sn NMR spectra of MTBE-Sn-(TMSA) 3 in benzene-d 6 are shown in Figures 9 and 10, respectively. The spectra showed the following chemical shifts: 1H NMR (C 6D 6) δ 0.0 (s, 27H, CH 3), δ 0.9 (s, 9H, CH 3), δ 3.6 (s, 2H, CH 2); 119Sn NMR (C 6D 6) δ -313.

[0082] MTBE-Sn-(TMSA) 3 and 2% Cu(OtBu) were placed in an inert flask with a stir bar, and tert-butyl alcohol (10 equivalents) and triethylamine (10 equivalents) were added. The volatiles were slowly removed to yield MTBE-Sn-(OtBu) 3 as a viscous liquid. The 1H and 119Sn NMR spectra of MTBE-Sn-(OtBu) 3 in benzene-d 6 are shown in Figures 11 and 12, respectively. The spectrum shows the following chemical shifts: 1H NMR (C 6D 6) δ 1.4 (s, 9H, CH 3), δ 1.5 (s, 27H, CH 3), δ 4.0 (s, 2H, CH 2); 119Sn NMR (C 6D 6) δ -245. [synthesis] [(C , 6, H , 5, )O(CH , 2, )Sn(CC(SiCH , 3, )) , 3, ] [、] [MPE-Sn-(TMSA) , 3, ] [and converted to] [(C , 6, H , 5, )O(CH , 2, )Sn(OtBu) , 3, ] [、] [MPE-Sn-(OtBu) , 3, ]

[0083] Ethynyltrimethylsilane (3.1 equivalents) and diethyl ether (1.5 ml / equivalent) were added to a vacuum-purged reaction vessel equipped with a thermometer, stirrer, and addition funnel. The solution was cooled to <0°C, and n-butyllithium (2.0 M in diethyl ether, 3.0 equivalents) was slowly added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred for 30 minutes, and then tin(II) chloride (1 M in THF, 1.0 equivalents) was added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred at 20°C for 2 hours. The internal temperature was then allowed to reach <0°C, and chloromethoxybenzene (1.1 equivalents) was added, maintaining the internal temperature below 10°C. The solution was stirred for an additional 30 minutes, after which the volatiles were removed under vacuum. The solid was washed with pentane and filtered. Volatiles were removed under vacuum, and recrystallization was performed from hexane (approximately 1 mL / 1 g of product) at -20°C to yield MPE-Sn-(TMSA) 3 as a crystalline solid. The 1H and 119Sn NMR spectra of MPE-Sn-(TMSA) 3 in benzene-d 6 are shown in Figures 13 and 14 , respectively. The spectra showed the following chemical shifts: 1H NMR (C 6D 6) δ 0.0 (s, 27H, CH 3), δ 4.0 (s, 2H, CH 2), δ 6.8 (d, 3H, CH), δ 7.0 (t, 2H, CH); 119Sn NMR (C 6D 6) δ -317.

[0084] MPE-Sn-(TMAS) 3 and 2% Cu(OtBu) were placed in an inert flask with a stir bar, and tert-butyl alcohol (10 equivalents) and triethylamine (10 equivalents) were added. The volatiles were slowly removed to yield MPE-Sn-(OtBu) 3 as a viscous liquid. The 1H and 119Sn NMR spectra of MPE-Sn-(OtBu) 3 in benzene-d 6 are shown in Figures 15 and 16, respectively. The spectrum showed the following chemical shifts: 1H NMR (C 6D 6) δ 1.8 (s, 27H, CH 3), δ 4.8 (s, 2H, CH 2), δ 7.3 (d, 3H, CH), δ 7.7 (t, 2H, CH); 119Sn NMR (C 6D 6) δ -248. [(CH , 3, O) , 2, CHCH , 2, Sn(CC(SiCH , 3, )) , 3, ] [、] [DME-Sn-(TMSA) , 3, ] [Synthesis]

[0085] Ethynyltrimethylsilane (3.1 equivalents) and diethyl ether (1.5 mL / equivalent) were added to a vacuum-purged reaction vessel equipped with a thermometer, stirrer, and addition funnel. The solution was cooled to <0°C, and n-butyllithium (2.0 M in diethyl ether, 3.0 equivalents) was slowly added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred for 30 minutes, and then tin(II) chloride (1 M in THF, 1.0 equivalents) was added, maintaining the internal temperature below 10°C. Upon completion, the solution was stirred at 20°C for 2 hours. The internal temperature was then allowed to reach <0°C, and 1,1-dimethoxy-2-bromoethane (1.1 equivalents) was added, maintaining the internal temperature below 10°C. The solution was stirred for an additional 30 minutes, after which the volatiles were removed under vacuum. The solid was washed with pentane and filtered. Volatiles were removed under vacuum, and recrystallization was performed from hexane (approximately 1 mL / 1 g of product) at -20°C to provide DME-Sn-(TMSA) 3 as a crystalline solid. The 1H and 119Sn NMR spectra of DME-Sn-(TMAS) 3 in benzene-d 6 are shown in Figures 17 and 18 , respectively. The spectra showed the following chemical shifts: 1H NMR (C 6D 6) δ 0.0 (s, 27H, CH 3), δ 1.5 (d, 2H, CH 2), δ 3.1 (s, 6H, CH 3), δ 4.5 (m, 1H, CH); 119Sn NMR (C 6D 6) δ -301. [CF , 3, CH , 2, OCH , 2, Sn(OtBu) , 3, , FET-Sn-(OtBu) , 3, ] [Synthesis]

[0086] n-Butyllithium (1.03 mL, 2.53 mmol, 2.45 M in hexane) was added to a cold solution (-50°C) of trimethylsilylacetylene (0.248 g, 2.53 mmol) in diethyl ether (4 mL). After several minutes, a slurry of tin(II) chloride (0.160 g, 0.845 mmol) in THF (4 mL) was added. The contents were warmed to 0°C and stirred for 2 hours. The flask was cooled again to -50°C and 2-(chloromethoxy)-1,1,1-trifluoroethane (0.125 g, 0.845 mmol) was added. The resulting reaction mixture was allowed to warm to room temperature over 16 hours, at which point the solvent was removed in vacuo to yield CF3CH2OCH2Sn(TMSA)3. The contents were recrystallized from pentane and converted to FET-Sn(OtBu) 3 using excess 5 M triethylamine / tert-butanol, and then further purified by fractional distillation. [CH , 3, OCH , 2, Sn(OtBu) , 3, ] [、] [MOM-Sn-(OtBu) , 3, ] [Synthesis]

[0087] MOM-Sn-(OtBu) 3 was synthesized according to the method of the '192 patent cited above. [Example] [2] [:Solution preparation and storage stability]

[0088] Appropriate amounts of the organotin alkoxide synthesized in the above examples were dissolved in 4-methyl-2-pentanol (Solvent 1) or n-propanol (Solvent 2) containing a controlled amount of added water to form various solutions of approximately 0.05 M [Sn]. The prepared solutions were inspected and observed over time for the formation of precipitates, and the results are presented in Table 1 below. Depending on the level of stability observed, each sample was assigned a grade from A to F according to the following scale: A = no precipitation observed, B = precipitation observed after one month, C = precipitation observed after one week, D = precipitation observed after one day, and F = precipitation observed after less than one day.

[0089] Table 1 Solvent water content (ppm) Compound solvent 300 1000 2000 3000 MPE-Sn-(OtBu) 3 1 A A A A MTBE-Sn-(OtBu) 3 1 A A A A MOE-Sn-(OtBu) 3 1 A A A A THP-Sn-(OtBu) 3 1 A A B A MOM-Sn-(OtBu) 3 1 A A F F mTHP-Sn-(OtBu) 3 1 B B D D MPE-Sn-(OtBu) 3 2 A A A MTBE-Sn-(OtBu) 3 2 A F F F MOE-Sn-(OtBu) 3 2 F THP-Sn-(OtBu) 3 2 A A B MOM-Sn-(OtBu) 3 2 A C C mTHP-Sn-(OtBu) 3 2 D D D

[0090] For the R1OR2SnL3 compositions shown in Table 1, it was observed that compounds having hydrocarbyl ligands (having R1 and / or R2 groups with more than one carbon atom) were more stable to precipitation in solutions with higher water content than the methoxy-methyltin tris(tert-butyloxy) compositions. [Example] [3] [:Resist coating, film processing and image formation]

[0091] This example illustrates the formation, solubility, and patterning of a radiation-patternable coating or film comprising the R 1OR 2SnL 3 compound of Example 1. [Membrane solubility]

[0092] A series of solutions containing the R 1OR 2SnL 3 compounds selected from Example 1 were prepared by dissolving appropriate amounts of organotin compounds in solvents with controlled water concentrations to form 0.05 M [Sn] solutions. Coatings were then prepared by spin-coating the solutions onto thermal oxide / Si substrates (approximately 100 nm SiO x ). The coatings were baked at either 100°C for 120 seconds or 150°C for 120 seconds.

[0093] The baked coatings were immersed in various developer solutions to assess their solubility. Developers A through M were used and are identified in Table 2. Solubility was assessed by visual inspection of the remaining film thickness on the developed substrates. Film solubility was graded on a scale of A to F based on the remaining film thickness, where A = completely soluble (i.e., no substantial film remains), B = mostly soluble with some residue remaining, C = partially soluble, D = mostly insoluble, and F = no observed thickness loss.

[0094] The indicated organotin compositions were dissolved in 4-methyl-2-pentanol (Solvent 1), n-propanol (Solvent 2), or tert-pentanol (Solvent 3). Prior to the addition of the organotin compounds, a controlled amount of water was added to the solvent of each sample to produce low (300 ppm H₂O), medium (2000 ppm H₂O), or high (4000 ppm H₂O) water concentrations as measured by Karl-Fisher titration.

[0095] Tables 3 and 4 show the solubility of the films baked at 100°C for 120 seconds and 150°C for 120 seconds, respectively.

[0096] Table 2 developer Chemicals A 2-Heptanone B 10% HCOOH in 2-heptanone C 10% acetic acid in propylene glycol methyl ether acetate (PGMEA) D 5% acetic acid in PGMEA E n-Propanol F 2.38% Tetramethylammonium Hydroxide (aqueous solution)—The samples were rinsed with pure water after development. G 10% formic acid (aqueous solution) H 70 / 30 (volume ratio) PGMEA / propylene glycol methyl ether I water J 4-Methyl-2-pentanol K 10% acetic acid (aqueous solution) L Hexane M Toluene

[0097] Table 3 Resist ROR'-Sn-(OtBu) 3 compounds Resist solvent developer Solvent water concentration Membrane solubility MOM 2 A Low F MOM 2 A high F MOM 2 B Low A MOM 2 B high A MOM 2 C Low A MOM 2 C high A MOE 1 A middle F MOE 3 A high F MOE 2 A high D MOE 1 B Medium F MOE 3 B high F MOE 2 B high B MOE 1 C Medium D MOE 3 C high F MOE 2 C high B MOE 1 E Medium F MOE 3 E high F MOE 2 E high B MOE 1 F Medium D MOE 3 F high A MOE 2 F high A MOE 1 G Medium F MOE 3 G high B MOE 2 G high A MOE 1 J Medium F MOE 3 J high F MOE 2 J high C MOE 1 K Medium F MOE 3 K high B MOE 2 K high B THP 1 A low A THP 1 D low A THP 1 F low A THP 1 G Low A THP 1 H Low A THP 1 I Low A THP 1 L a Low F THP 1 Ma Low F mTHP 1 A Low A mTHP 1 D Low B mTHP 1 I Low B mTHP 1 M Low F Notes: (a) The samples were not baked.

[0098] Table 4 Resistors ROR'-Sn-(OtBu) 3 compounds Resistants and solvents Developer Solvent water concentration Membrane solubility THP 1 A Low A THP 1 F Low A THP 1 G Low A THP 1 H Low A THP 1 I Low A THP 1 K Low A THP 1 D Low A THP 2 D Low A mTHP 1 A Low B mTHP 1 D Low B mTHP 1 I Low B mTHP 1 M Low F MOM 2 A high F MOM 2 K high F

[0099] As shown in Tables 3 and 4, MOE films exhibit high solubility in most solvents except non-polar solvents (e.g., toluene and hexane). In contrast, comparative examples containing MOM films only exhibit solubility in non-aqueous acidic developers (e.g., 10% acetic acid in PGMEA) at 100°C. At 150°C, MOM films appear insoluble in the tested solvents, while MOE films remain soluble at 150°C. The high solubility of MOE films after baking can provide improved negative-tone patterning behavior by enabling the removal of unirradiated areas of the coating, thereby reducing defects such as scum. Interestingly, MOE films remain soluble in water even after baking at 150°C. Similarly, films containing cyclic ether hydrocarbon ligands THP and mTHP exhibit high solubility in polar solvents at both 100°C and 150°C, relative to MOM films. For compounds having hydrocarbyl ligands with R 1 and / or R 2 groups containing more than one carbon atom, such improved solubility can improve the available process window of organotin photoresists and enable higher processing temperatures and alternative developers. [contrast]

[0100] A 0.05 M [Sn] solution of THP-Sn-(OtBu)3 was prepared by dissolving and thoroughly mixing the appropriate mass of the THP-Sn-(OtBu)3 precursor in 4-methyl-2-pentanol containing 300 ppm H2O (measured by Karl-Fischer titration). The precursor solution was deposited by spin coating onto a 10 nm spin-on-glass (SOG)-coated silicon wafer to achieve a dry film thickness of 24.0 ± 0.4 nm. After deposition and coating, the wafer was baked at 100°C for 60 seconds. Patterned EUV radiation exposure was performed on an ASML NXE3400C EUV scanner operating in an open frame to produce the contrast arrays. The exposed samples were then baked at 140°C, 160°C, and 180°C and subsequently developed using a 5% acetic acid solution in PGMEA. Finally, the film was baked at 250°C to remove developer residue and densify the pattern. The thickness of each exposed pad was measured by ellipsometer and then plotted against dose to generate the comparative curves in Figure 19. The data is summarized in Table 5 below, where the gelation dose (Dg) and the initial dose increase (D0) were obtained from the graph.

[0101] Table 5 Post-exposure bake temperature (°C) Dg (millijoules / cm²) D 0 (mJ / cm²) Contrast value 140 44.32 21.24 3.13 160 28.81 12.52 2.76 180 12.52 5.92 3.08 [Example] [4] [:Radiolysis-induced pyrolysis]

[0102] This example demonstrates the improvement in carbon loss during the post-exposure bake process for a composition comprising oxygen-substituted hydrocarbyl ligands.

[0103] Three resist solutions were prepared using THP-Sn-(OtBu) 3 (precursor 1), mTHP-Sn-(OtBu) 3 (precursor 2), and n-butyl-Sn-(OtAm) 3, where OtAm is an alkoxide of tertiary amyl alcohol. The solution containing Precursor 1 was prepared in methyl isobutyl carbinol (MIBC) at a [Sn] concentration of 0.04 M, while the solution containing Precursor 2 was prepared in 1-propanol at a [Sn] concentration of 0.028 M. Due to differences in viscosity and volatility, different concentrations were prepared to produce resist films of similar thickness after spin coating. A comparative example containing n-butyl-Sn-(OtAm) 3 prepared in MIBC at a [Sn] concentration of 0.05 M was also prepared.

[0104] The resist solution was spin-coated under conditions that produced a film thickness of approximately 24 nm. After deposition, each wafer underwent a post-deposition bake at 100°C for 60 seconds to completely dry the sample. The wafers were then exposed using an ASML TwinScan NXE 3400 exposure tool by creating an array of open-frame exposure pads at varying doses. The wafers then underwent a post-exposure bake at 180°C for 60 seconds. After the post-exposure bake, each pad on each wafer was analyzed using FTIR spectroscopy to measure the peak area corresponding to the absorbance of the CH stretch (from 2800 cm⁻¹ to 3000 cm⁻¹) to determine the amount of carbon present in each pad. The measured peak areas were then normalized to the peak area of ​​an unexposed region on the same wafer to calculate relative peak areas. The relative peak areas were plotted against dose and are shown in Figure 20.

[0105] As shown in Figure 20, in all cases, the peak area corresponding to CH absorbance decreases with increasing dose. In other words, exposure to EUV radiation followed by baking results in a loss of carbon content in the exposed areas. For resist films deposited from Precursor 1 and Precursor 2, the amount of carbon lost after exposure and baking is greater than that lost in the comparative example. The dose-dependent carbon loss rate (i.e., the decrease in relative peak area relative to dose) is significantly improved for resists prepared from Precursor 1 and Precursor 2, with Precursor 2 exhibiting the greatest carbon loss. For example, at a dose of 20 mJ / cm² and after baking at 180°C for 60 seconds, nearly 70% of the carbon remains in Precursor 1, and nearly 55% remains in Precursor 2. In contrast, for the comparative example, approximately 85% of the carbon remains under the same conditions. Generally speaking, a higher carbon loss rate indicates more efficient cleavage of Sn-C bonds after EUV exposure and post-exposure bake, which in turn can translate into higher contrast, lower dose, and improved patterning.

[0106] Furthermore, it was found that the resist film deposited from Precursor 2 had the largest carbon loss. This result indicates that the organotin resist with tertiary carbon bound to Sn and oxygen located in the hydrocarbyl ligand improves the carbon loss rate. [Example] [5] [:Blend composition]

[0107] This example demonstrates the effect of dose (dose size) on the performance of a blended resist film when generating an image pattern with 16 nm lines on a 32 nm pitch. Blends 1 through 9 and a comparative blend were prepared using the precursors listed in Table 6. The molar ratios and solvents used to prepare the blends are shown in Table 7.

[0108] Table 6 Components Precursors A Tertiary butyl-Sn-(OtAm) 3 B Methyl-Sn-(OtAm) 3 C Ethyl-Sn-(OtAm) 3 Compound 1 THP-Sn-(OtBu) 3 Compound 2 mTHP-Sn-(OtBu) 3

[0109] Table 7 Resistant Blends composition solvent Blend 1 65% A 15% C 20% Compound 1 50% MIBC 50% 1-propanol Blend 2 65% A 25% C 10% Compound 1 50% MIBC 50% 1-propanol Blend 3 70% A 10% B 20% Compound 1 50% MIBC 50% 1-propanol Blend 4 70% A 20% B 10% Compound 1 50% MIBC 50% 1-propanol Blend 5 80% A 20% Compound 2 1-Pentanol Blend 6 75% A 15% B 10% Compound 2 45% MIBC 55% 1-propanol Blend 7 65% A 15% B 20% Compound 2 45% MIBC 55% 1-propanol Blend 8 70% A 20% B 10% Compound 2 45% MIBC 55% 1-propanol Blend 9 60% A 20% B 20% Compound 2 45% MIBC 55% 1-propanol Comparison of blends 80% A 20% B MIBC

[0110] Blends 1 through 9, along with the comparative blend, were then spin-coated onto 10nm SOG-coated silicon wafers and subsequently post-deposition baked at 100°C for 60 seconds to form a resist film approximately 24nm thick. The resist-coated wafers were then exposed to EUV radiation on an ASML dual-scan NXE 3400 exposure tool by exposing an array of fields on each wafer at varying doses. Following EUV exposure, each wafer underwent a post-exposure bake at 160°C, 170°C, 180°C, 190°C, or 200°C for 60 seconds and then developed using 5% acetic acid in PGMEA. The wafers were then hard-baked at 250°C for 60 seconds.

[0111] The wafers were then analyzed using a Hitachi CDSEM to determine the dose-to-size (DtS) corresponding to 16nm lines on a 32nm pitch (16p32). The critical dimension (CD) of each 16p32 feature was measured and plotted against field dose, with DtS interpolated. In some cases, the DtS values ​​exceeded the tested conditions, and the corresponding DtS values ​​were indicated as being below the minimum dose tested. The results are shown in Table 8.

[0112] Table 8 Dose of size (16p32, mJ / cm2) Post-exposure bake temperature Resistant Blends 160°C 170°C 180°C 190°C 200°C Blend 1 64.1 54 44.5 35.1 Blend 2 72.4 59.8 49.1 36.3 Blend 3 74.7 60.5 49.7 38.9 Blend 4 73 56.5 46.7 36.4 Blend 5 68.9 64.2 53.8 45.2 Blend 6 70.6 56 41.5 31.8 Blend 7 65.7 48.3 31.3 < 30 Blend 8 70.2 51.2 35.1 < 30 Blend 9 65.6 44.1 < 30 < 30 Comparative example 58.9 47 39.6

[0113] Relative to the control blend, at a PEB of 180°C, lower values ​​of dosage to size were obtained for most blends containing Compound 1 and Compound 2. At higher temperatures, much lower values ​​of dosage to size were obtained. [Example] [6] [:Non-blended composition]

[0114] To demonstrate the improved sensitivity of organotin resists with ether-based ligands, a direct comparison was made between the lithographic performance of resist films prepared from a cyclopentylSn(OtAm)3 precursor and a THPSn(OtBu)3 precursor. The precursors were dissolved in MIBC to yield 0.05 M cyclopentylSn(OtAm)3 and 0.04 M THPSn(OtBu)3. The samples were then spin-coated onto S-silicon wafers coated with 10 nm SOG and subjected to a post-application bake at 100°C for 60 seconds to form a resist film approximately 24 nm thick. The resist-coated wafers were then exposed to EUV radiation on an ASML dual-scan NXE 3400 exposure tool by exposing an array of fields at varying doses per wafer. After EUV exposure, each wafer was subjected to a post-exposure bake at 180°C for 60 seconds and then developed using 5% acetic acid in PGMEA. The wafer was then hard-baked at 250°C for 60 seconds.

[0115] The wafers were then analyzed using a Hitachi CDSEM to determine the dose-to-size (DtS) corresponding to 16nm lines on a 32nm pitch (16p32). The critical dimension (CD) of each 16p32 feature was measured and plotted against field dose, with DtS interpolated. In some cases, the DtS values ​​exceeded the tested conditions, and the corresponding DtS values ​​were indicated as being below the minimum dose tested. The results are shown in Table 9.

[0116] Table 9 Resist RSnL 3 solvent Large and small doses (16p32, mJ / cm2) Cyclopentyl-Sn-(OtAm) 3 MIBC 88.8 THP-Sn-(OtBu) 3 MIBC 44.9

[0117] As shown in Table 9, compared to the unsubstituted cycloalkyl group bonded to Sn, the presence of an oxygen atom in the alkyl group bonded to Sn corresponds to a much lower size dose value. [Further inventive concepts]

[0118] 1. A radiation-patternable coated substrate comprising a substrate and a coating layer having an average thickness of from about 1 nm to about 75 nm and represented by the formula RSnOn(OH)3-2n, forming an oxo-hydroxyl network, wherein R is a hydrocarbyl ether group having 1 to 30 carbon atoms and 0 < n < 3 / 2, and wherein in a puddle development step carried out after baking at 150 °C for 120 seconds, the regions of the coating layer are soluble in 2-heptanone.

[0119] 2. The radiation-patternable coated substrate according to inventive concept 1, wherein R is an aromatic ether represented by the formula Ar-O-(CR'2)m-, wherein Ar is an aromatic organic moiety, m is an integer from 1 to 4; R' is hydrogen or a hydrocarbyl group having 1 to 6 carbon atoms and optionally heteroatoms.

[0120] 3. The radiation-patternable coated substrate according to inventive concept 2, wherein m is , R' is hydrogen, and Ar is -C6H5.

[0121] 4. The radiation-patternable coated substrate according to inventive concept 1, wherein R is a cyclic ether represented by the formula ring(O(CR'2)nCR'R0-), wherein R' is hydrogen or a hydrocarbyl group having 1 to 6 carbon atoms and optionally heteroatoms, n is an integer from 1 to 8, optionally, the CR'2 group may be replaced by O to form a cyclic polyether, and two R' groups may combine to form a polycyclic structure; R0 is a bond or a straight-chain or branched-chain hydrocarbyl group having 1 to 5 carbon atoms and optionally heteroatoms.

[0122] 5. The radiation-patternable coated substrate according to inventive concept 4, wherein R0 is a bond, the cyclic ether is directly bonded to the Sn atom, and O(CR"2)nCR' is O(CH2)3CH-, O(CH2)4CH- or O(CH2)4CCH3-.

[0123] 6. The radiation-patternable coating substrate of inventive concept 1, wherein R is a halogenated ether represented by the formula R1OR0C(R2R3)-, R0 is a bond or a linear or branched hydrocarbon group having 1 to 5 carbon atoms and optionally heteroatoms, R1 is a hydrocarbon group having 1 to 10 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, R2 and R3 are independently hydrogen, a halogen, or a hydrocarbon group having 1 to 7 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, and at least one of R1, R2, and R3 has a halogen atom.

[0124] 7. The radiation-patternable coated substrate of inventive concept 6, wherein R 1 or R 2 comprises -CF 3.

[0125] 8. The radiation-patternable coating substrate of inventive concept 1, wherein R is a polyether represented by the formula R1R2R3C-, wherein R1, R2, and R3 are independently a hydrocarbon group having 1 to 19 carbon atoms and optionally having an unsaturated bond and / or optionally a heteroatom, and at least two of R1, R2, and R3 are ether moieties, or at least one of R1, R2, and R3 is a diether moiety.

[0126] 9. A method for patterning a structure, the method comprising: irradiating the radiation patternable coated substrate as described in Inventive Concept 1 to form a latent image; and The latent image is developed to form a physical pattern.

[0127] A1. A method for patterning a substrate, the method comprising: A substrate having an organotin coating is irradiated with patterned EUV radiation to form a latent image, wherein the coating has an average thickness of about 1 nm to about 75 nm and a composition represented by the formula RSnO n(OH) 3-2n, forming an oxo-hydroxyl network, wherein R is a hydrocarbon ether group having 1 to 30 carbon atoms, and 0 <n<3 / 2; The latent image is developed using a developer solvent to remove the unirradiated coating to form a developed image, thereby forming an image having a critical dimension of no more than about 50 nanometers and a dose of no more than about 80 millijoules / square centimeter.

[0128] A2. The method according to invention concept A1, wherein the polar organic developer solvent comprises a solvent blend containing at least two solvents, wherein at least 55 volume % of one or more solvents independently have a Hansen solubility parameter δH + δP sum not exceeding about 16 (joules / cubic centimeter) 1 / 2, and about 0.25 volume % to about 45 volume % of one or more solvents independently have a Hansen solubility parameter δH + δP sum of at least about 16 (joules / cubic centimeter) 1 / 2.

[0129] A3. The method according to invention concept A1, wherein the organotin coating is formed by the steps of: (A) contacting the surface of the substrate with the vapor of an organotin composition to form a deposit on the surface of the substrate; and heating the substrate having the deposit on its surface, wherein the conditions of the contact and / or heating provide hydrolysis of the hydrolyzable ligand L to form a coating comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, where 0 < n < 3 / 2; or (B) depositing a solution onto the surface of the substrate to form an initial coated surface, the solution comprising an organic solvent and an organotin composition having a concentration, measured based on the tin cation concentration, of from about 0.0025 M to about 1.4 M; and heating the substrate having the initial coated surface, wherein the conditions of the deposition and / or heating provide hydrolysis of the hydrolyzable ligand L to form a coating comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, where 0 < n < 3 / 2.

[0130] A4. The method according to invention concept A1, wherein heating the substrate having the initial coated surface is carried out at a temperature of from about 50 °C to about 250 °C for a time of from about 0.1 minute to about 10 minutes.

[0131] A5. The method according to invention concept A1, further comprising heating the substrate having a latent image to a temperature of from about 50 °C to about 250 °C for a time of from about 0.1 minute to about 10 minutes.

[0132] A6. The method according to invention concept A1, wherein R is an aromatic ether represented by the formula Ar-O-(CR' 2) m-, wherein Ar is an aromatic organic moiety, m is an integer from 1 to 4; R' is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and optionally heteroatoms.

[0133] A7. The method of inventive concept A6, wherein m is 1, R' is hydrogen, and Ar is -C6H5.

[0134] A8. The method of inventive concept A1, wherein R is a cyclic ether represented by the formula cyclo(O(CR'2)nCR'R0-), wherein R' is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and, optionally, heteroatoms, and n is an integer from 1 to 8. Optionally, the CR'2 group may be substituted with O to form a cyclic polyether, and two R' groups may be combined to form a polycyclic structure; and R0 is a bond or a linear or branched hydrocarbon group having 1 to 5 carbon atoms and, optionally, heteroatoms.

[0135] A9. The method of inventive concept A8, wherein R 0 is a bond, the cyclic ether is directly bonded to the Sn atom, and O(CR" 2) nCR' is O(CH 2) 3CH-, O(CH 2) 4CH-, or O(CH 2) 4CCH 3-.

[0136] A10. The method of inventive concept A1, wherein R is a halogenated ether represented by the formula R1OR0C(R2R3)-, R0 is a bond or a linear or branched hydrocarbon group having 1 to 5 carbon atoms and optionally heteroatoms, R1 is a hydrocarbon group having 1 to 10 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, R2 and R3 are independently hydrogen, a halogen, or a hydrocarbon group having 1 to 7 carbon atoms and optionally unsaturated bonds and / or optionally heteroatoms, and at least one of R1, R2, and R3 contains a halogen atom.

[0137] A11. The method as described in inventive concept A10, wherein R 1 or R 2 comprises -CF 3.

[0138] A12. The method of inventive concept A1, wherein R is a polyether represented by the formula R1R2R3C-, wherein R1, R2, and R3 are independently a hydrocarbon group having 1 to 19 carbon atoms and optionally having an unsaturated bond and / or optionally a heteroatom, and at least two of R1, R2, and R3 are ether moieties, or at least one of R1, R2, and R3 is a diether moiety.

[0139] B1. A method for synthesizing an organotin composition, the method comprising: A halide hydrocarbyl compound (RX, wherein X is a halogen atom) is reacted with an organometallic composition (comprising a SnL3 moiety bonded to a metal cation M) to form an alkali tin composition, wherein M is an alkali metal, alkaline earth metal, and / or pseudo-alkaline earth metal (Zn, Cd, or Hg), and L is an amide ligand that produces an alkali tin triamide compound, or an acetylide ligand that produces an alkali tin triacetylide compound, to form a monohydrocarbyltin triamide (RSn(NR'2)3) or a monohydrocarbyltin triacetylide (RSn(C≡CRs)3), respectively, and Rs is SiR' 3 or R', three R" are independently H or R', and R' is independently a hydrocarbon group having 1 to 31 carbon atoms and optionally an unsaturated carbon-carbon bond, optionally an aromatic group and optionally a heteroatom, and wherein R is a hydrocarbon ether group having 1 to 31 carbon atoms and optionally an unsaturated carbon-carbon bond, optionally an aromatic group and optionally a heteroatom, which includes an aromatic ether represented by the formula Ar-O-(CR'2)m-, or a hydrocarbon ether represented by the formula cyclo(O(CR'2) The present invention relates to a cyclic ether represented by the formula R1R2R3C-, wherein Ar is an aromatic organic moiety, m is an integer from 1 to 4, each R' is hydrogen, a halogen, or a hydrocarbon group having 1 to 6 carbon atoms and optionally heteroatoms, n is an integer from 1 to 8, R1, R2 and R3 are independently a hydrocarbon group having 1 to 19 carbon atoms, at least two of R1, R2 and R3 are ether moieties, or at least one of R1, R2 and R3 is a diether moiety.

[0140] B2. The method of inventive concept B1, wherein the method produces an organotin composition as described herein.

[0141] C1. A method for forming an organotin composition, the method comprising: An alkylating agent selected from the group consisting of RMgX, R2Zn, RZnNR'2 or a combination thereof is reacted with Sn(NR'2)4 in a solution comprising an organic solvent, Where X is a halogen, wherein R' is a hydrocarbon group having 1 to 10 carbon atoms, and wherein R is a hydrocarbyl ether group having 1 to 31 carbon atoms and optionally an unsaturated carbon-carbon bond, optionally an aromatic group, and optionally a heteroatom, including an aromatic ether represented by the formula Ar-O-(CR'2)m-, or a cyclic ether represented by the formula cyclo(O(CR'2)nCR'-), or a polyether represented by the formula R1R2R3C-, wherein Ar is an aromatic organic moiety, m is an integer from 1 to 4, each R' is hydrogen, a halogen, or a hydrocarbyl group having 1 to 6 carbon atoms and optionally a heteroatom, n is an integer from 1 to 8, R1, R2, and R3 are independently a hydrocarbyl group having 1 to 19 carbon atoms, at least two of R1, R2, and R3 are ether moieties, or at least one of R1, R2, and R3 is a diether moiety.

[0142] C2. The method of inventive concept C1, wherein the method produces an organotin composition as described herein.

[0143] This application claims priority to co-pending U.S. provisional patent application 63 / 343,331 to Jilek et al., filed on May 18, 2023, and entitled “Organotin Compositions Having Oxygen Heteroatoms in Hydrocarbyl Ligands,” which is incorporated herein by reference.

[0144] The foregoing embodiments are intended to be illustrative and not limiting. Additional embodiments are within the scope of the claims. Moreover, although the invention has been described with reference to specific embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. Any incorporation by reference of the above-mentioned documents is limited so as not to incorporate any subject matter that is contrary to the explicit disclosure herein. To the extent that specific structures, compositions, and / or processes are described herein as having components, elements, ingredients, or other partitions, it is understood that, unless otherwise expressly stated, the disclosure herein encompasses those specific embodiments, embodiments comprising those specific components, elements, ingredients, other partitions, or combinations thereof, and embodiments consisting essentially of those specific components, ingredients, other partitions, or combinations thereof, and that such embodiments may include additional features that do not alter the essential properties of the subject matter, as suggested in the discussion. The term "about" as used herein refers to the expected uncertainty in the relevant value, as understood by one of ordinary skill in the art in the particular context.

[0145] none

Claims

1. An organotin composition represented by the formula RSnL 3, wherein L is a hydrolysable ligand, and R is (A) an aromatic ether represented by the formula Ar-O-(CR' 2) m-, (B) a cyclic ether represented by the formula cyclo(O(CR" 2) nCR'R 0-), (C) a haloether represented by the formula R 1OR 0C(R 2R 3)-, or (D) a polyether represented by the formula R1R2R3C-, wherein Ar is an aromatic organic moiety; m is an integer from 1 to 4; R' is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and heteroatoms as desired; n is an integer from 1 to 8; R" is hydrogen or a hydrocarbon group having 1 to 4 carbon atoms and heteroatoms as desired; and CR" is, as desired, The two groups can be substituted with O to form cyclic polyethers, and the two R" groups can be combined to form a polycyclic structure; R0 is a hydrocarbon group with 1 to 5 carbon atoms and heteroatoms as desired; R1 is a hydrocarbon group with 1 to 10 carbon atoms and unsaturated bonds and / or heteroatoms as desired; R2 and R3 are independently hydrogen, halogen, or hydrocarbon groups with 1 to 7 carbon atoms and unsaturated bonds and / or heteroatoms as desired, wherein at least one of R1, R2, and R3 has a halogen atom; and R1, R2, and R3 are independently hydrocarbon groups with 1 to 19 carbon atoms and unsaturated bonds and / or heteroatoms as desired, wherein at least two of R1, R2, and R3 are ether moiety, or at least one of R1, R2, and R3 is diether moiety.

2. The organotin composition as claimed in claim 1, wherein the R group is an aromatic ether represented by the formula Ar-O-(CR' 2) m-, wherein the Ar group is an aromatic organic moiety, and the m group is an integer from 1 to 4; and the R' group is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and heteroatoms as desired.

3. The organotin composition as described in claim 2, wherein the m series is 1 and the R' series is hydrogen.

4. The organotin composition as described in claim 3, wherein the Ar group is -C6H5.

5. The organotin composition as claimed in claim 1, wherein the R group is an aromatic ether represented by the formula Ar-O-(CR' 2) m-, wherein the Ar group is -C 5NH 4, -C 10H 7, -CH 2C 6H 5 or -C 6H 4C 6H 5.

6. The organotin composition as claimed in claim 1, wherein R is a cyclic ether represented by the formula (O(CR'2)nCR'R0-), wherein R' is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms and heteroatoms as desired, n is an integer from 1 to 8, wherein, if desired, the CR'2 group may be substituted with O to form a cyclic polyether, and two R' groups may be combined to form a polycyclic structure; and R0 is a bond or a straight-chain or branched hydrocarbon group having 1 to 5 carbon atoms and heteroatoms as desired.

7. The organotin composition as described in claim 6, wherein R is represented by O(CR" 2) nCR'R 0- and R 0 is a bond, and the cyclic ether system is directly bonded to the Sn atom.

8. The organotin composition as described in claim 7, wherein O(CR'2)nCR' is O(CH2)3CH-, O(CH2)4CH-, or O(CH2)4CCH3-.

9. The organotin composition as claimed in claim 6, wherein at least one CR'2 group is substituted with an oxygen atom, such that the cyclic ether system is a polyether.

10. The organotin composition as claimed in claim 6, wherein the O(CR'2)nCR'R0- system is a cyclic (CH2OCH2OCH2CH)-.

11. The organotin composition as claimed in claim 1, wherein R is a haloether represented by the formula R1OR 0C(R2R3)-, R0 is a straight-chain or branched hydrocarbon group having 1 to 5 carbon atoms and heteroatoms as desired, R1 is a hydrocarbon group having 1 to 10 carbon atoms and having unsaturated bonds and / or heteroatoms as desired, R2 and R3 are independently hydrogen, halogen, or hydrocarbon groups having 1 to 7 carbon atoms and having unsaturated bonds and / or heteroatoms as desired, and wherein at least one of R1, R2, and R3 has a halogen atom.

12. The organotin composition as described in claim 11, wherein R1 or R2 comprises -CF3.

13. The organotin composition as claimed in claim 11, wherein R0 is a bond and R2 and / or R3 contains a fluorine group.

14. The organotin composition as claimed in claim 1, wherein R is a polyether represented by the formula R1R2R3C-, wherein R1, R2 and R3 are independently hydrocarbon groups having 1 to 19 carbon atoms and having unsaturated bonds and / or heteroatoms as desired, at least two of R1, R2 and R3 are ether moieties, or at least one of R1, R2 and R3 is a diether moiety.

15. The organotin composition as described in claim 14, wherein R1 is -OCH3, R2 is OCH3, and R3 is hydrogen.

16. The organotin composition as described in claim 14, wherein R1 comprises -OCH2OCH3.

17. A solution comprising an organic solvent and an organotin composition as described in claim 1, wherein the concentration of the organotin composition, as measured based on the concentration of tin cations, is from about 0.0025 M to about 1.4 M.

18. The solution as claimed in claim 17, wherein the organic solvent comprises a secondary or tertiary alcohol having 3 to 8 carbon atoms.

19. The solution as described in claim 17 further comprises a second, different organotin composition as described in claim 1.

20. The solution as claimed in claim 17 further comprises a tin composition represented by the formula RaSnL'3, wherein L' is a hydrolyzable ligand that is the same as or different from L, and Ra is represented by the formula RbRcRdC-, wherein Rb, Rc, and Rd are independently hydrogen or straight-chain or branched alkyl groups having 1 to 4 carbon atoms.

21. The solution as claimed in claim 20, wherein Rb, Rc, and Rd are each -CH3 groups.

22. The solution as claimed in claim 17, wherein the organotin composition has an R group, the R group being an aromatic ether represented by the formula Ar-O-(CR' 2) m-.

23. The solution as claimed in claim 17, wherein the organotin composition has an R group, the R group being a cyclic ether represented by the formula (O(CR" 2) nCR'R 0-).

24. The solution as claimed in claim 23, wherein R0 is a bond, the cyclic ether is directly bonded to the Sn atom, and the O(CR"2)nCR' system is O(CH2)3CH-, O(CH2)4CH- or O(CH2)4CCH3-.

25. A method for forming a radiation-patternable coated substrate, the method comprising: (A) contacting a substrate surface with a vapor of an organotin composition as described in claim 1 to form a deposit on the substrate surface; and heating the substrate having the deposit on the surface, wherein the contact and / or heating conditions provide for the hydrolysis of the hydrolyzable ligands L to form a coating comprising RSnO n(OH) 3-2n, forming an oxo-hydroxo network, wherein 0 < n < 3 / 2; or (B) depositing a solution onto the substrate surface to form an initial coated surface, the solution comprising an organic solvent and an organotin composition as described in claim 1 with a concentration of about 0.0025 M to about 1.4 M based on the concentration of tin cations; and heating the substrate having the initial coated surface, wherein the deposition and / or heating conditions provide for the hydrolysis of the hydrolyzable ligands L to form a coating comprising RSnO n(OH) 3-2n. The coating of n(OH)3-2n forms an oxo-hydroxy network, where 0 < n < 3 / 2.

26. A radiation-patternable coated substrate comprising a substrate and a coating having an average thickness of about 1 nanometer to about 75 nanometers and forming an oxo-hydroxyl network represented by the formula RSnO n(OH) 3-2n, wherein R is a hydrocarbon ether group having 1 to 30 carbon atoms and 0 < n < 3 / 2, wherein in a puddle development step performed after baking at 150°C for 120 seconds, the regions of the coating are soluble in 2-heptanone.

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