Tin compounds and resist solutions using the same, pattern forming method, thin film, patterned thin film, and method for producing tin compounds

Abstract

Provided is a tin compound that is a high-performance resist material capable of having high purity and uniform solubility. A tin compound having a tin atom, an organic group R, and an oxygen ligand and / or a hydroxyl ligand, wherein the diffraction angle 2θ (°) of the peak of the maximum intensity in X-ray diffraction measurement is present in the range of 5.00° to 15.00°, the half-value width of the peak of the maximum intensity is in the range of 1.00° to 4.00°, and the aforementioned organic group R has 1 to 30 carbon atoms.

Description

Technical Field

[0001] This invention relates to tin compounds and resist solutions using the tin compounds, patterning methods, thin films, patterned thin films, and methods for manufacturing tin compounds. Background Technology

[0002] In recent years, against the backdrop of the shift towards a highly information-based society, there is a demand for processing larger volumes of information at higher speeds and with higher precision, leading to increasingly sophisticated technologies related to semiconductor devices, such as integrated circuits.

[0003] The evolution of semiconductor design has necessitated the formation of unprecedentedly finer features on semiconductor substrate materials, with each feature being approximately 22 nanometers (nm) or smaller, and in some cases, less than 10 nm. One challenge in fabricating devices with such fine features is the ability to reliably and reproducibly form photolithographic masks with sufficient resolution. Achieving feature sizes smaller than the wavelength of light requires complex high-resolution techniques such as multiple patterning. Therefore, the development of photolithography techniques using shorter wavelengths of light, such as extreme ultraviolet (EUV) light with wavelengths of 10 nm to 15 nm (e.g., 13.5 nm), is of great importance.

[0004] Existing organic chemical amplification resists (CARs), particularly in the EUV region, exhibit low adsorption coefficients and are prone to diffusion blurring due to photoactivated chemical species, high linewidth roughness (LWR), and pattern collapse, posing potential drawbacks for use in EUV lithography. Therefore, there is a need for improved EUV photoresist materials with properties such as higher sensitivity, lower linewidth roughness (LWR), and superior etch resistance.

[0005] Therefore, in recent years, metallic materials using organotin compounds and the like have begun to be used as resists particularly suitable for EUV. Specifically, for example, alkyltin oxo-hydroxy compounds synthesized by hydrolysis of high-purity monoalkyltin compounds have been reported as resist materials for EUV applications, and it has been reported that very fine negative patterning can be achieved with high resolution and low linewidth roughness (LWR). In addition, excellent sensitivity has been reported as an alkyl group, especially a branched alkyl group (Patent Document 1).

[0006] In addition, it has been reported that monoalkyltin compounds, which contain few dialkyltin compounds as impurities, exhibit excellent gas release reduction when used as resist materials (Patent Document 2).

[0007] Furthermore, alkyltin oxo-hydroxy compounds synthesized from hydrolyzable tin compounds having two or more alkyl groups have been reported to achieve a balance between high sensitivity and low linewidth roughness (LWR) (Patent Document 3). Additionally, examples of synthesizing alkyltin oxo-hydroxy compounds by mixing organometallic compounds having hydrolyzable groups without alkyl groups have been reported (Patent Document 4).

[0008] Existing technical documents

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Application Publication No. 2021-21953

[0011] Patent Document 2: Japanese Patent Publication No. 2021-519340

[0012] Patent Document 3: Japanese Patent Publication No. 2019-500490

[0013] Patent Document 4: Japanese Patent Application Publication No. 2023-27078 Summary of the Invention

[0014] The problem that the invention aims to solve

[0015] However, the alkyltin oxy-hydroxy compounds reported to date are insufficient to meet the performance requirements as photoresist materials. In particular, the crystallinity of tin compositions, which affects solubility (relative to photoresist solvents and developer solvents) related to performance and quality, has not been adequately studied as a photoresist raw material. Specifically, the suitable range for the crystal structure and crystallinity of alkyltin oxy-hydroxy compounds in photoresist materials remains unclear. Furthermore, no solution has yet been proposed to address the dual challenges of controlling crystal structure and crystallinity while synthesizing high-purity photoresist materials.

[0016] Therefore, in this invention, under such circumstances, a tin compound is provided as a high-performance resist material capable of having high purity and uniform solubility.

[0017] Methods for solving problems

[0018] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that alkyltin oxy-hydroxy compounds (including compositions) with specific crystal structures and crystallinity can provide excellent performance when used as resist materials.

[0019] Furthermore, by using a combination of a monoalkyltin compound containing a specific structure (precursor) and a precursor with a specific composition as raw materials, it is possible to achieve both the high purity required for resist materials and the control of preferred crystallinity.

[0020] That is, the present invention has the following aspects. [1]

[0022] A tin compound having tin atoms, an organic group R, and oxygen ligands and / or hydroxyl ligands, wherein, The diffraction angle 2θ (°) of the peak with the highest intensity in X-ray diffraction measurements exists in the range of 5.00° to 15.00°. The full width at half maximum (FWHM) of the maximum intensity peak is 1.00°–4.00°. The organic group R mentioned above has 1 to 30 carbon atoms. [2]

[0024] According to the tin compound described in [1], wherein the tin compound is composed of the formula RSnO (3 / 2-X / 2) (OH) X (where 0≤x≤3) represents the expression. [3]

[0026] According to the tin compound described in [1], wherein the tin compound contains a compound with the chemical formula (RSn). 12 O 14 (OH)6 +2 Compounds that represent cations. [4]

[0028] The tin compound according to any one of [1] to [3], wherein, 119 The sum of the peak integrals (k1) of 5-coordinate Sn (-250ppm to -350ppm) and the sum of the peak integrals (k2) of 6-coordinate Sn (-450ppm to -600ppm) in Sn-NMR, relative to the sum of the peak integrals (k1+k2) of 6-coordinate Sn (-450ppm to -600ppm), is given by... 119 The ratio of the sum of all peak integral values ​​(including k1 and k2) in the range of 1000ppm to -1000ppm detected by Sn-NMR to (k3) [(k1+k2) / (k3)] is greater than 0.9. [5]

[0030] The tin compound according to any one of [1] to [4], wherein, 119 The ratio (k1 / k2) of the total integrated peak value (k1) of 5-coordinate Sn (-250ppm to -350ppm) to the total integrated peak value (k2) of 6-coordinate Sn (-450ppm to -600ppm) in Sn-NMR is 0.5 to 2.5. [6]

[0032] The tin compound according to any one of [1] to [5], wherein the full width at half maximum (FWHM) of the maximum intensity peak is 1.43° to 4.00°. [7]

[0034] The tin compound according to any one of [1] to [6], wherein the number of carbon atoms of the organic group R is 3 to 10. [8]

[0036] The tin compound according to any one of [1] to [7], wherein the organic group R is a hydrocarbon group. [9]

[0038] The tin compound according to any one of [1] to [7], wherein the above-mentioned organic group R is a hydrocarbon group, and 50 mol% or more of the substituents constituting the above-mentioned hydrocarbon group are secondary hydrocarbon groups R. 2 .

[10]

[0040] An anti-corrosion solution comprising any one of [1] to [9] a tin compound and an organic solvent.

[11]

[0042] A pattern forming method includes: a step of coating a resist solution described in

[10] onto a substrate; a step of exposing the substrate to radiation; and a step of developing the substrate using a developer.

[12]

[0044] A thin film on a substrate comprising any one of the tin compounds described in [1] to [9].

[13]

[0046] A patterned thin film on a substrate, comprising any one of the tin compounds described in [1] to [9].

[14]

[0048] A method for manufacturing a substrate, comprising the pattern forming method described in

[11] .

[15]

[0050] A monoalkyltin compound, represented by RSnX2Y(B1).

[0051] (In the above general formula (B1), R is an organic group having 1 to 30 carbon atoms. X and Y are hydrolyzable groups with different chemical formulas. X is selected from OR', NR'2, and C≡CR', and Y is selected from OR'.) Y NR' Y 2. C≡CR' Y The above R' and R' Y An organic group having 1 to 10 carbon atoms. Where X is NR'2 and / or Y is NR'2. Y In case 2, the above R' and R' YThey can be the same or different independently; in addition, R' and R' in the molecule Y In the case of two or more instances, their structures can be different, or they can bond together to form a ring structure.

[16]

[0053] According to the monoalkyltin compound described in

[15] , wherein the hydrolyzable groups X and Y are NR'2 and NR' respectively. Y 2. The substituent NR'2 of X and the substituent NR' of Y mentioned above. Y 2 are different chemical formulas.

[17]

[0055] According to the monoalkyltin compound described in

[15] or

[16] , wherein the hydrolyzable groups X and Y are OR' and OR', respectively. Y The substituent OR' of X and the substituent OR' of Y mentioned above Y These are different chemical formulas.

[18]

[0057] The monoalkyltin compound according to any one of

[15] to

[17] , wherein the hydrolyzable group X is a substituent NR'2, and the hydrolyzable group Y is a substituent OR' Y .

[19]

[0059] The monoalkyltin compound according to any one of

[15] to

[18] , wherein the hydrolyzable group X is a substituent OR' and the hydrolyzable group Y is a substituent NR'. Y 2.

[20]

[0061] A monoalkyltin composition comprising 50 mol% to 99.99 mol% of a monoalkyltin compound RSnX3 (A1) and more than 0.01 mol% and less than 50 mol% of RSnX2Y (B1).

[0062] In the above general formulas (A1) and (B1), R is an organic group having 1 to 30 carbon atoms. X and Y are hydrolyzable groups with different chemical formulas. X is selected from OR', NR'2, and C≡CR', and Y is selected from OR'. Y NR' Y 2. C≡CR' Y The above R' and R' Y An organic group having 1 to 10 carbon atoms. When X is NR'2 and / or Y is NR'2, R' and R'' are... Y They can be the same or different independently. Additionally, R' and R'' in the molecule...Y In the case of two or more instances, their structures can be different, or they can bond together to form a ring structure. [twenty one]

[0064] A monoalkyltin composition comprising more than 0.01 mol% and less than 50 mol% of a monoalkyltin compound RSnX3 (A1) and less than 50 mol% to 99.99 mol% of RSnX2Y (B1).

[0065] In the above general formulas (A1) and (B1), R is an organic group having 1 to 30 carbon atoms. X and Y are hydrolyzable groups with different chemical formulas. X is selected from OR', NR'2, and C≡CR', and Y is selected from OR'. Y NR' Y 2. C≡CR' Y The above R' and R' Y An organic group having 1 to 10 carbon atoms. When X is NR'2 and / or Y is NR'2, R' and R'' are... Y They can be the same or different independently. Additionally, R' and R'' in the molecule... Y In the case of two or more instances, their structures can be different, or they can bond together to form a ring structure. [twenty two]

[0067] The monoalkyltin composition according to

[20] or

[21] comprises the above-mentioned RSnX3(A1), the above-mentioned RSnX2Y(B1) and other monoalkyltin compounds, wherein the sum of the contents of the above-mentioned RSnX3(A1) and the above-mentioned RSnX2Y(B1) is 80 mol% or more. [twenty three]

[0069] A method for manufacturing a tin compound, comprising manufacturing a tin compound having tin atoms, an organic group R, and oxygen ligands and / or hydroxyl ligands, wherein the diffraction angle 2θ (°) of the maximum intensity peak in X-ray diffraction measurements is between 5.00° and 15.00°, the half-width at half-maximum (FWHM) of the maximum intensity peak is between 1.00° and 4.00°, and the organic group R has 1 to 30 carbon atoms, wherein... The manufacturing method includes the following steps 1 and 2: <Step 1> uses the monoalkyltin composition described in

[20] or

[21] as raw material; <Step 2> Contact the above raw materials with water and / or water vapor. [twenty four]

[0071] According to the method for manufacturing tin compounds described in

[23] , in step 2 above, the raw material is brought into contact with liquid water in a complex of organic solvent.

[25]

[0073] The method for manufacturing tin compounds according to

[23] or

[24] includes, in step 2, a step of preparing a composition by combining 100 parts by mass of the above-mentioned raw materials with 100 parts by mass or more of an organic solvent.

[26]

[0075] The method for manufacturing a tin compound according to any one of

[23] to

[25] , wherein the half-width of the maximum intensity peak is 1.43° to 4.00°.

[0076] Invention Effects

[0077] The tin compound of the present invention is useful as a high-performance photoresist material due to its high purity and uniform solubility. Attached Figure Description

[0078] Figure 1 This is the XRD pattern of tin hydrolysate H1A.

[0079] Figure 2 This is the XRD pattern of tin hydrolysate H1C.

[0080] Figure 3A It is tin hydrolysate H1A 119 Wide-range Sn-NMR spectrum.

[0081] Figure 3B It is tin hydrolysate H1A 119 Detailed Sn-NMR spectrum.

[0082] Figure 3C It is tin hydrolysate H1A 1 Detailed H-NMR spectrum.

[0083] Figure 3D This is the spectrum obtained by electrospray ionization mass spectrometry (ESI-MS) analysis of tin hydrolysate H1A. Detailed Implementation

[0084] The present invention will now be described based on examples of methods for carrying out the invention. However, the present invention is not limited to the embodiments described below.

[0085] It should be noted that when expressed as "α~β" (α and β are arbitrary numbers) in this invention, unless otherwise specified, it includes the meaning of "above α and below β", and also includes the meaning of "preferably more than α" or "preferably less than β".

[0086] In this invention, the expressions “above α” (α being any number) or “below β” (β being any number) also include the meaning of “preferably more than α” or “preferably less than β”.

[0087] In this invention, "γ and / or δ (γ and δ are arbitrary components or elements)" means only γ, only δ, or the combination of γ and δ.

[0088] Regarding the numerical ranges described in stages in this invention, the upper or lower limit of the numerical range for a certain stage can be arbitrarily combined with the upper or lower limit of the numerical ranges for other stages. Furthermore, the upper or lower limit of the numerical range described in this specification can also be replaced with the values ​​shown in the embodiments.

[0089] In this invention, "main component" refers to the component that has a significant impact on the properties of the object. The content of this component is usually 50% by mass or more in the object, preferably 55% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, and may also be 100% by mass.

[0090] The following is a detailed description of a tin compound according to one embodiment of the present invention.

[0091] <<Tin Hydrolysate>>

[0092] One embodiment of the tin compound (P1) of the present invention is a tin compound having tin atoms, an organic group R, and an oxygen ligand and / or a hydroxyl ligand, wherein the organic group R has 1 to 30 carbon atoms. Hereinafter, the substituent bonded to the tin atom is sometimes referred to as a ligand.

[0093] In the X-ray diffraction measurements of this compound (P1), the diffraction angle 2θ (°) of the peak with the maximum intensity is between 5.00° and 15.00°, and the half-width at half-maximum of the peak with the maximum intensity is between 1.00° and 4.00°.

[0094] In this embodiment, a particular objective is to provide a high-performance photoresist material that exhibits both high purity and uniform solubility. To achieve this objective, it has been found that the addition of a tin compound RSnX2Y with different hydrolytic groups as a precursor is effective in simultaneously controlling the crystallinity and purity of the hydrolysate.

[0095] It should be noted that, for convenience, the tin compound (P1) of the above embodiment is sometimes referred to as "this tin hydrolysate".

[0096] Specifically, this tin hydrolysate (P1) is a tin compound having tin atoms, organic groups R, and oxygen ligands and / or hydroxyl ligands. In this manner, each tin atom typically has a ligand (sometimes also called a "substituent") selected from the organic group R, oxygen ligands (Sn-O structure, Sn=O structure), and hydroxyl ligands (Sn-OH structure). This tin hydrolysate (P1) sometimes has two or more organic groups R in one molecule, and sometimes one tin atom has two or more organic groups R, but the effects of the present invention are more effectively obtained when the organic group R contains only a single chemical structure in the tin compound.

[0097] The tin hydrolysate (P1) is usually formed by the aforementioned metals and ligands, but may also contain other metal atoms and ligands (substituents) without impairing its properties.

[0098] This tin hydrolysate (P1) is synthesized, for example, by hydrolysis using the method disclosed in Japanese Patent Application Publication No. 2021-21953, with RSnX3 and RSnX2Y (monoalkyl tin compounds, sometimes referred to as "precursors") as the main raw materials.

[0099] (The above X is a hydrolyzable group [a substituent that can form an oxygen ligand (Sn-O structure) or a hydroxyl ligand (Sn-OH structure) through a hydrolysis reaction].)

[0100] Specifically, RSnX3 and RSnX2Y are hydrolyzed, condensed, or otherwise reacted with water or other suitable reagents under appropriate conditions to obtain tin compounds represented by the following compositional formula (P2). The compounds represented by this compositional formula are those containing RSnOOH and RSn(OH)3 as hydrolysates of RSnX3 and RSnX2Y, and those containing tin atoms and organic groups, and containing oxygen ligands and / or hydroxyl ligands, as condensates. For example, compounds containing tin atoms with organic groups (optionally having hydroxyl ligands) forming a network structure via oxygen ligands.

[0101] [Formula]RSnO (1.5-(x / 2)) (OH) x (In the formula, 0≤x≤3)···(P2)

[0102] The reaction formula for obtaining the above tin hydrolysate (P2) is shown below. Examples of reaction formulas using RSnX3 and RSnX2Y are shown respectively.

[0103] (Reaction 1)

[0104] ·RSnX3+3H2O→RSn(OH)3+3HX

[0105] ·RSn(OH)3→RSnO (1.5-(x / 2)) OHx +(x / 2)H2O

[0106] (Reaction 2)

[0107] ·RSnX2Y+3H2O→RSn(OH)3+2HX+HY

[0108] ·RSn(OH)3→RSnO (1.5-(x / 2)) OH x +(x / 2)H2O

[0109] In these reaction equations, when using precursors such as RSnX2Y that contain more than two hydrolyzable groups X and Y in a single molecule, the reaction rates of the hydrolyzable groups X and Y reacting with water differ. As a result, this can sometimes affect the composition, structure, crystallinity, and purity of the tin hydrolysate generated from the above reactions. In particular, by using a mixture of precursors containing structurally similar RSnX3 and RSnX2Y, reactions (reaction 1) and (reaction 2) can be carried out simultaneously in the reaction system. By combining the two reaction equations, a tin hydrolysate with more suitable composition, crystallinity, and purity can be formed.

[0110] Furthermore, in the above reaction, the byproducts containing HX and HY after hydrolysis can be removed during processing (filtration, washing, heating, drying, volatilization, etc.) so that no unwanted impurities remain in the tin hydrolysate. It should be noted that other tin compounds (e.g., tin compounds such as R2SnX2(A2) and SnX4(A3)) may also affect the control of crystallinity, etc. However, when these tin compounds are introduced into the obtained tin hydrolysate, they may change the alkyl skeleton and number of the tin hydrolysate, causing problems as a resist material (reduced purity, foreign matter generation, increased gas release, reduced sensitivity, increased roughness, etc.). Therefore, RSnX2Y is preferred in this regard because it allows control of the composition, structure, crystallinity, etc., of the tin hydrolysate without causing the problems described above as a resist material.

[0111] Among the compounds shown in this tin hydrolysate (P1), tin compounds with specific structures and numbers of tin atoms are sometimes used as high-performance photoresist materials. For example, a compound containing a tin dodecomer represented by the following chemical formula (tin hydrolysate (P3)) is a stable, football-shaped tin dodecomer cluster compound that is useful as a photoresist material.

[0112] As a chemical formula, it is a cationic compound as shown below.

[0113] [Formula](RSn) 12 O 14 (OH)6 +2 ...(P3)

[0114] (In the above formula, +2 represents a divalent cation.)

[0115] In addition, tin hydrolysate (P3) is usually a divalent cationic compound that is stabilized by a counter anion (Z). The salt formed by combining with a monovalent counter anion (Z) has the following chemical formula.

[0116] [Formula](RSn) 12 O 14 (OH)6(Z)2

[0117] There are no particular limitations on the counter anion (Z), and examples include OH anion, RCO2 anion, HCO2 anion, F anion, Cl anion, etc.

[0118] Examples of specific compounds that are tin hydrolysates (P3) include, for example, the following synthetic examples described in the literature.

[0119] (nBuSn) 12 O 14 (OH)6 +2 The reported synthesis is described in Eychenne-Baron et al., "New synthesis of the nanobuilding block {(BuSn)}". 12 O 14 (OH)6} 2+ and exchange properties of {(BuSn) 12 O 14 (OH)6}(O3SC6H4CH3)2",J.Organometallic Chemistry 1998,567,137-142

[0120] (iPrSn) 12 O 14 (OH)6 +2 The reported synthesis is described in Puff et al., "Zur hydrolysevon monoorganylzinn-tri halogeniden(III.Isolierung und Roentgenstrukturanalyse von Verbindungen mit dem nueartigen Kaefig-ion[(i-PrSn)]. 12 O 14 (OH)6 +2[J. Organometallic Chemistry 1989, 373, 173-184.] These compounds were identified by NMR, single-crystal X-ray structure, etc., and the analytical results are cited as supporting evidence in the embodiments of this invention.

[0121] [Organic group R]

[0122] The tin hydrolysates (P1, P2, P3, and so on) contain an organic group R bonded to a Sn atom. The organic group R has 1 to 30 carbon atoms.

[0123] Considering the ease with which the R-group is removed during EUV exposure and the vaporization of the resulting components containing the R-group, the upper limit for the number of carbon atoms in the organic group R is 30 or less, preferably 20 or less, and more preferably 10 or less. Furthermore, from the viewpoint of the stability of the removed components, the lower limit for the number of carbon atoms in the organic group R is 1 or more, preferably 2 or more, and more preferably 3 or more.

[0124] Furthermore, the organic group R can be, for example, a haloalkyl group; a hydrocarbon group containing heteroatoms such as oxygen or nitrogen atoms; or a hydrocarbon group, etc., and can be used alone or in combination of two or more. Among these, when used as a photoresist, the gas released during detachment after exposure is a hydrocarbon, and a hydrocarbon group is preferred from the perspective of minimizing the impact on the semiconductor device. On the other hand, in the case of containing heteroatoms, sometimes the photoresist properties such as high decomposition resistance to EUV light are improved, resulting in enhanced sensitivity.

[0125] When the organic group R is a hydrocarbon group, preferred examples of hydrocarbon groups are as follows. Examples include primary alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, and n-hexyl; secondary alkyl groups such as isopropyl, isobutyl, sec-butyl, and isopentyl; tert-butyl, tert-pentyl, cyclopentyl, cyclohexyl, methylcyclopentyl, and methylcyclohexyl; aryl groups such as phenyl, tolyl, benzyl, and naphthyl; aromatic hydrocarbon groups such as phenethyl, α-methylbenzyl, and 2-phenyl-2-propyl; alkenyl groups such as vinyl, 1-propenyl, allyl, and 3-butenyl; alkyl groups substituted with halogen atoms such as 2-fluoroethyl and 2-iodoethyl; and so on.

[0126] If we further list the structures, the following compounds can be listed. R in the diagram. a and R bThe organic group R is an organic group having 1 to 10 carbon atoms. Examples of organic groups R include halogenated hydrocarbon groups; hydrocarbon groups containing heteroatoms such as oxygen atoms and nitrogen atoms; and hydrocarbon groups. These can be used alone or in combination of two or more. From the perspective of effectively utilizing the effects of the present invention, it is preferable to use only one type, rather than two or more. When used as a photoresist, the gas released during detachment after exposure is a hydrocarbon. From the perspective of minimizing the impact on the semiconductor device, a hydrocarbon group is preferred. The substituent A on the aromatic ring is a halogen atom or an organic group having 1 to 10 carbon atoms. Examples of such organic groups include hydrocarbon groups containing heteroatoms such as nitrogen atoms, and hydrocarbon groups are preferred.

[0127] [Chemical Formula 1]

[0128] [Chemical Formula 2]

[0129] (Preferred hydrocarbon group)

[0130] Of the hydrocarbon groups shown above, the primary hydrocarbon group R 1 secondary hydrocarbon group R 2 tertiary hydrocarbon group R 3 Classified as cyclic hydrocarbon group R c Saturated and unsaturated hydrocarbon groups sometimes exhibit different properties when used as corrosion resist materials. From the viewpoint of sensitivity (photoreactivity), the case where the hydrocarbon group is saturated is preferred. Among the various categories, primary hydrocarbon groups R are listed as preferred substituents. 1 secondary hydrocarbon group R 2 tertiary hydrocarbon group R 3 From the viewpoint of sensitivity (photoreactivity) when used as an EUV resist, easily detachable secondary hydrocarbon groups (R) are preferred. 2 tertiary hydrocarbon group R 3 Further optimization of tertiary hydrocarbon group R 3 From a hydrophobic perspective, tertiary hydrocarbon R 3 The group that best enhances hydrophobicity near the tin atom is preferred from the viewpoint of solubility control. However, if the hydrophobicity is too high, a secondary hydrocarbon group (R) is sometimes preferred. 2 .

[0131] [Compositional Analysis of the Tin Hydrolysate]

[0132] This tin hydrolysate can be utilized using NMR ( 1 H-NMR, 13 C-NMR, 119Sn-NMR and related NMR and mass spectrometry are used to analyze the composition of substituents. In NMR, the overall composition of a sample can be analyzed, such as the ligands (substituents R, etc.) with tin atoms, the coordination number of each tin atom, the structure of substituents R, and the quantification of the average composition of samples containing substituents R.

[0133] Tin hydrolysate 119 The ratio (k1 / k2) of the total integrated peak values ​​(k1) of 5-coordinate Sn (-250ppm to -350ppm) and the total integrated peak values ​​(k2) of 6-coordinate Sn (-450ppm to -600ppm) in Sn-NMR is preferably 0.5 to 2.5, more preferably 1.0 to 2.4, even more preferably 1.2 to 2.3, and particularly preferably 1.3 to 2.2. In this tin hydrolysate, 5-coordinate Sn has a high tendency to have OH groups, while 6-coordinate Sn has more coordination moieties, thus having a high tendency to bond OH groups only through Sn-O-Sn bonds without bonding OH groups. That is, it can be said that the higher the value of k1 / k2, the more OH groups there are, and the lower the value of k1 / k2, the fewer OH groups there are. The number of OH groups causes changes in the parameters of the tin compound's polarity related to the solubility in the resist solvent, and the parameters of the tin compound's hydrophobicity and hydrophilicity related to the resist performance. From the perspective of controlling its performance balance, it is preferable to control k1 / k2 within the above range.

[0134] Based on the molecular weight of the ions observed in mass analysis (sometimes also called mass spectrometry, "MS") (especially from the viewpoint of sensitivity and detection capability of unstable compounds based on soft ionization, ESI-mass analysis (electrospray ionization) is preferred), the molecular weight and molecular formula of the compounds contained in the tin compound can be determined. That is, what is observed in NMR is the average composition of the entire sample, while the composition of organic groups R observed in mass analysis represents the composition of organic groups R contained in a molecule. In addition, by quantifying the intensity of each peak, the composition containing the most organic groups R in a molecule can be detected. Examples of these analyses are also illustrated in the section on examples.

[0135] (Purity of this tin hydrolysate)

[0136] The method for calculating the purity of (tin hydrolysate) based on NMR is shown below. Here, the "mol%" representing the purity in tin atom conversion refers to the ratio of tin atoms in the target compound to the total number of tin atoms in all compounds (including unidentified compounds). In practice... 119Sn-NMR uses the sum of the integrated values ​​of all observed peaks as the denominator and the integrated value of the peak of the compound being studied as the numerator for calculation. It should be noted that... 119 Sn-NMR measurements were performed in the range of 1000 to -1000 ppm, which is sufficient to determine the range of compounds analyzed in this study. For example, the purity of tin hydrolysates composed of 5-coordinate Sn and 6-coordinate Sn was determined by... 119 The sum of the integrated peak values ​​(k1) of 5-coordinate Sn (-250ppm to -350ppm) and the sum of the integrated peak values ​​(k2) of 6-coordinate Sn (-450ppm to -600ppm) in Sn-NMR is set as (k1+k2). 119 When the total integrated values ​​of all other peaks detected by Sn-NMR (in the range of 1000 to -1000 ppm, including k1 and k2) are set as (k3), the value is expressed as (k1+k2) / (k3). The larger this value, the lower the concentration of impurities other than 5-coordinate Sn and 6-coordinate Sn in the tin hydrolysate, which is therefore preferred. The lower limit is preferably 0.7 or more, more preferably 0.8 or more, further preferably 0.9 or more, particularly preferably 0.95 or more, and most preferably 0.99 or more. It should be noted that from the viewpoint of the determination sensitivity of this method, if peaks corresponding to k1 and k2 cannot be detected, it can be considered as 0.99 or more. The upper limit is 1.

[0137] According to this calculation method, compounds containing only tin atoms are included in the calculation. For example, if additives or solvents are added after the manufacture of this tin hydrolysate according to various uses, even if it contains this tin hydrolysate and tin compounds as other impurities, it is included in the scope of this tin hydrolysate as long as it contains this tin hydrolysate.

[0138] As 119 In Sn-NMR analysis, to improve sensitivity, the tin hydrolysate is dissolved at a high concentration and analyzed (using a solvent dissolved at a high concentration). This is achieved using conditions including two or more cumulative measurements (1000 times or more, preferably 10000 times or more), sufficient relaxation time (1 second or more), reverse gate decoupling, and an appropriate measurement range (1000 to -1000 ppm). As a result, by using these methods, the detection limit for trace amounts of tin compounds can be reached as low as 0.01 mol%. Furthermore, even if the sensitivity of the measured peak is insufficient, the detection sensitivity can be further improved by using a highly sensitive NMR (e.g., using a low-temperature probe in 600 MHz NMR), enabling detection up to 0.001 mol%. Examples of such analyses are also illustrated in the embodiments.

[0139] [Crystallization of this tin hydrolysate]

[0140] When tin hydrolysate is used as a photoresist material to form a thin film, it is preferably a solid to ensure resistance to semiconductor processes (exposure, development, etching, etc.). In particular, controlling the properties of this solid, such as particle shape, form, crystallinity, and surface condition, within specific ranges is sometimes preferred as a photoresist material. Regarding crystallinity, it is important to control solubility (which contributes to development performance, coating performance, ease of filtration, and storage stability of the photoresist solution) and the surface condition of the solid (which contributes to hydrophobicity / hydrophilicity, substrate adhesion, etc.) while maintaining the properties derived from the chemical formula. Furthermore, crystallinity also affects adhesion to the substrate, roughness after exposure, ease of pattern collapse, and solubility during development; therefore, it needs to be appropriately controlled within the range required for its performance as a photoresist. Specifically, if the crystallinity is too high, it is difficult to dissolve in the photoresist solvent, causing problems in processes such as dissolution, filtration, and storage. Furthermore, excessively high crystallinity during coating and drying can sometimes lead to cracks or collapse of the patterns at the crystal interfaces or on the crystal surfaces. During exposure and development, high crystallinity results in larger crystal sizes, which can sometimes increase the roughness of the developed pattern. Conversely, insufficient crystallinity leads to poor adhesion to the substrate or low strength of the resist film. Consequently, the resist film may peel off during coating, drying, exposure, and development, or the pattern may collapse, or the roughness of the developed pattern may increase. As described above, in resist materials with excellent solubility, adhesion, and roughness, it is necessary to appropriately control the ratio of crystalline to amorphous components (amorphous matter) within a suitable range of crystallinity to achieve this specific range.

[0141] As an analytical method for crystallinity, XRD (X-ray diffraction) based analysis can be used, and it can be applied to any of the following: powders, molded bodies, thin films, and patterned thin films after exposure of the tin hydrolysate. Among the values ​​obtained from XRD, particularly the diffraction angle 2θ (°) of the maximum intensity peak and the half-width at half-maximum (FWHM) of the maximum intensity peak, as well as the number of detected peaks, can be used as numerical values ​​to indicate the crystallinity of the obtained tin compound. As shown in this embodiment, values ​​to two decimal places are valid for analytical precision; when comparing the diffraction angle 2θ (°) and FWHM (°), values ​​greater than 0.01 (°) are considered meaningful. Specific measurement methods are also shown in the embodiments.

[0142] The diffraction angle 2θ (°) of the peak with the highest intensity of the tin hydrolysate is preferably 5.00 to 15.00°, more preferably 13.00° or less, even more preferably 11.00° or less, particularly preferably 10.00° or less, and especially preferably 9.00° or less. The lower limit is more preferably 5.50° or more, even more preferably 5.80° or more, and especially preferably 6.00° or more. The diffraction angle 2θ (°) of the peak with the highest intensity is related to the lattice plane spacing of the crystal. If it is within the above-mentioned preferred range, the crystals of the tin compound are arranged with appropriate lattice plane spacing, which suppresses pattern collapse during pattern formation as crystals with moderate crystallinity and intensity, and also achieves roughness reduction during the formation of fine patterns.

[0143] The preferred range for the half-width at half-maximum (FWHM) of the maximum intensity peak is 1.00 to 4.00°, more preferably 3.50° or less, particularly preferably 3.00° or less, especially preferably 2.50° or less, and even more preferably 2.00° or less. The lower limit is more preferably 1.05° or more, even more preferably 1.10° or more, particularly preferably 1.20° or more, particularly preferably 1.43° or more, and even more preferably 1.50° or more. The FWHM of the maximum intensity peak is particularly strongly correlated with the crystallinity of the tin compound. When the FWHM is within the above-mentioned preferred range, parameters such as the solubility (which contributes to developing performance, coating performance, ease of filtration process, and storage stability of the resist solution) and the surface state of the solid (which contributes to hydrophobicity / hydrophilicity, substrate adhesion, etc.) required by the above-mentioned resist material can be controlled within an appropriate range.

[0144] The number of peaks detected at a diffraction angle of 2θ (°) within the range of 5.00 to 15.00° is preferably 5 or less, preferably 3 or less, preferably 2 or less, and particularly preferably 1 or less. The lower limit is preferably 1 or more. It should be noted that 0 peaks indicates that no peaks were detected by the above analytical method. This tin hydrolysate tends to have lower crystallinity with fewer peaks, but if there are 0 peaks, it indicates that no crystal structure was detected at all. That is, if the number of peaks is within the above-mentioned preferred range, it has moderate crystallinity, and parameters such as the solubility required for the resist material (which contributes to development performance, coating performance, ease of filtration process, and storage stability of the resist solution) and the surface state of the solid (which contributes to hydrophobicity / hydrophilicity, substrate adhesion, etc.) can be controlled within an appropriate range.

[0145] [Solubility of this tin hydrolysate]

[0146] When this tin hydrolysate is used as a resist material, it is sometimes dissolved in the resist solvent described below, and used as a resist solution. The solubility of the tin hydrolysate refers to its solubility in the organic solvent used in preparing the resist solution. In the dissolved resist solution, it is preferable that it is completely dissolved without any insoluble matter or turbidity originating from the tin hydrolysate. Insoluble matter originating from the tin hydrolysate is a cause of performance degradation and malfunction when used as a resist material. Specific examples include performance degradation as a resist material due to defects in patterning (causing linewidth roughness (LWR), pattern collapse / reduced sensitivity), equipment contamination caused by impurities / foreign matter generated during etching, clogging / reduced productivity in filtration (filter) processes, etc.

[0147] (Resist solvent)

[0148] The tin hydrolysate dissolves in a resist solvent. Suitable resist solvents include organic solvents such as alcohols, esters, or combinations thereof. In particular, suitable solvents include, for example, aromatic compounds (e.g., xylene, toluene), ethers (anisole, tetrahydrofuran), halogen solvents (dichloromethane, chloroform), esters (propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate), alcohols (e.g., 4-methyl-2-pentanol, 4-methyl-2-propanol, 1-butanol, methanol, isopropanol, 1-propanol), and ketones (e.g., methyl ethyl ketone, cyclohexanone, 2-heptanone). These solvents can be used alone or in combination of two or more. For dissolving tin hydrolysates containing OH groups, an alcohol solvent is preferred, and 4-methyl-2-pentanol is more preferred. Furthermore, from the viewpoints of toxicity, regulatory restrictions, and volatility, 2-heptanone, 4-methyl-2-pentanol, and ethyl lactate are also preferred solvents in practical manufacturing processes.

[0149] The selection of these resist solvents is sometimes based on the solvent's own physical properties, such as solubility, volatility, flammability, toxicity, and viscosity. On the other hand, it is sometimes evaluated based on the stability (solution stability) of the resist solvent in the presence of dissolved tin hydrolysates or other materials. That is, after the components of the resist solution are dissolved and mixed, especially between solution preparation and film formation, the characteristics of the dissolved tin hydrolysates sometimes change as a result of the interactions (reactions, condensations, solvation, coordination, etc.) between the partial tin hydrolysates and the solvent. Solution stability based on these interactions is evaluated through the storage stability of the resist solution, as shown below. From the viewpoint of storage stability and stabilization based on OH group coordination, alcohol solvents are preferred.

[0150] (Methods for evaluating solubility)

[0151] The solubility of this tin hydrolysate is evaluated by comparing the turbidity (transparency) when the tin hydrolysate is dissolved in 4-methyl-2-pentanol at a certain concentration. Specifically, a mixture of tin hydrolysate equivalent to 2.0% by mass in 4-methyl-2-pentanol, as disclosed in Japanese Patent Application Publication No. 2019-500490, is prepared. The turbidity (transparency) of this liquid is compared with a standard turbidity solution, and the solubility of the corresponding tin hydrolysate is evaluated by visual inspection. As the standard turbidity solution, kaolin turbidity standard solutions (0 degrees (clear), 50 degrees, 100 degrees, 500 degrees, and 1000 degrees (white turbidity)) as shown in JIS K0110 are used. Turbidity values ​​close to those of the standard turbidity solution are evaluated as turbidity ratings from 1 to 5, as described below.

[0152] • Turbidity rating 1: 0 degrees (transparent)

[0153] Turbidity rating 2: 50 degrees

[0154] Turbidity rating 3: 100 degrees

[0155] Turbidity rating 4: 500 degrees

[0156] • Turbidity rating 5: 1000 degrees (cloudy)

[0157] [Storage stability of the resist solution]

[0158] The resist solution prepared by dissolving the tin hydrolysate should be stable without solid precipitation or sedimentation for at least one week, preferably two weeks or more, more preferably one month or more, further preferably three months or more, and particularly preferably six months or more, without stirring. As a specific method for evaluating storage stability, the solution sample can be stored at 20°C, and the turbidity can be evaluated using the same method after one week, two weeks, and one month following dissolution. Preferably, the turbidity in this evaluation does not change, indicating a stable resist solution that can be stored stably.

[0159] <<Raw Materials of Tin Hydrolysate>>

[0160] When manufacturing this tin hydrolysate as shown above, there are no particular limitations, but it is preferable to use the monoalkyltin compounds (A1) and (B1) shown below as raw materials (sometimes referred to as "precursors"). The monoalkyltin compounds (A1) and (B1) that can be used as precursors will be described below.

[0161] <Monoalkyltin compounds (A1)>

[0162] Monoalkyltin compounds (A1) are defined as compounds having one organic group and three hydrolytic groups X bonded to tetravalent tin. Specifically, they are represented by the following general formula (A1).

[0163] RSnX3 ····(A1)

[0164] (In the above general formula (A1), R is an organic group having 1 to 30 carbon atoms. X is selected from OR', NR'2, and C≡CR'. R' is an organic group having 1 to 10 carbon atoms. In addition, when there are two or more R's in the molecule, their structures can be different from each other, or they can be bonded together to form a cyclic structure.)

[0165] [Organic group R]

[0166] The organic group R has 1 to 30 carbon atoms. Examples of organic groups R include haloalkyl groups, hydrocarbon groups containing heteroatoms such as oxygen and nitrogen atoms, and hydrocarbon groups. These can be used alone or in combination of two or more. From the perspective of effectively maximizing the effects of the present invention, using them alone is preferred (except when using two or more in combination). When used as a photoresist, the gas released during detachment after exposure is a hydrocarbon; from the perspective of minimizing the impact on semiconductor devices, hydrocarbon groups are preferred. In the case of containing heteroatoms, sometimes the photoresist properties such as high decomposition resistance to EUV light are improved, resulting in enhanced sensitivity.

[0167] Regarding the number of carbon atoms in R, considering the ease with which the R group detaches during EUV exposure and the vaporization of the resulting R group components, the upper limit for the number of carbon atoms in R is 30 or less, preferably 20 or less, and more preferably 10 or less. Furthermore, from the viewpoint of the stability of the detached components, the lower limit is 1 or more, preferably 2 or more, and more preferably 3 or more.

[0168] Regarding the organic group R, when used as a photoresist, the gas released during detachment after exposure is a hydrocarbon. Considering minimizing the impact on the semiconductor device, a hydrocarbon group is preferred. Specific examples of preferred hydrocarbon groups include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, cyclopentyl, and cyclohexyl; aryl groups such as phenyl, tolyl, benzyl, and naphthyl; aromatic hydrocarbon groups such as phenethyl, α-methylbenzyl, and 2-phenyl-2-propyl; alkenyl groups such as vinyl, 1-propenyl, allyl, and 3-butenyl; and alkyl groups substituted with halogen atoms such as 2-fluoroethyl and 2-iodoethyl. These can be used alone or in combination of two or more.

[0169] Further listing of structures would yield the following compounds. R in the diagram a and R bAn organic group consisting of 1 to 10 carbon atoms. Examples of such organic groups include haloalkyl groups; hydrocarbon groups containing heteroatoms such as oxygen atoms and nitrogen atoms; and hydrocarbon groups. The substituent A on the aromatic ring is a halogen atom or an organic group with 1 to 10 carbon atoms. Examples of such organic groups include hydrocarbon groups containing heteroatoms such as oxygen atoms and nitrogen atoms; and hydrocarbon groups.

[0170] [Chemical Formula 3]

[0171] [Chemical Formula 4]

[0172] In addition, the hydrocarbon groups shown above are classified as primary hydrocarbon groups R. 1 secondary hydrocarbon group R 2 tertiary hydrocarbon group R 3 Typically, they are alkyl or aralkyl groups. As preferred examples of each classification, primary hydrocarbon R... 1 Examples include methyl, ethyl, n-propyl, n-butyl, isobutyl, benzyl, phenethyl, etc., and secondary hydrocarbon groups (R). 2 Examples include isopropyl, sec-butyl, cyclopentyl, cyclohexyl, cycloheptyl, α-methylbenzyl, etc., and tertiary hydrocarbon groups R. 3 Examples include tert-butyl, tert-pentyl, 1-methyl-cyclopentyl, 1-methyl-cyclohexyl, and 2-phenyl-2-propyl. They sometimes exhibit different properties when used as resist materials. Hereinafter, if hydrocarbon groups are used as representative examples, from the viewpoint of sensitivity (photoreactivity) when used in their respective preferred EUV resists, easily detachable secondary hydrocarbon groups R are preferred. 2 tertiary hydrocarbon group R 3 From a hydrophobic perspective, tertiary hydrocarbon R 3 The presence of a tin atom maximizes hydrophobicity and is preferred from a solubility control perspective. However, in cases where hydrophobicity is excessively high, a secondary hydrocarbon group (R) may be preferred. 2 Furthermore, from the perspective of thermal stability affecting distillation, primary hydrocarbon groups tend to be less prone to disproportionation and can sometimes be easily purified. On the other hand, secondary and tertiary hydrocarbon groups are prone to disproportionation reactions, especially those with fewer carbon atoms (6 or less). These groups are unstable during distillation, and distillation, which usually achieves high purification efficiency, is often difficult due to thermal decomposition. Therefore, in the reaction stage before purification, such as distillation, it is more important to obtain high-purity tin compounds with low content of byproducts with similar boiling points.

[0173] [Substituent X]

[0174] The substituent X is not limited in structure as long as it is a hydrolyzable group capable of undergoing hydrolysis or similar reactions. Preferred examples, considering high reactivity, include OR', NR'2, and C≡CR'. From the viewpoint of hydrolysis reactivity, OR' and NR'2 are more preferred. R' is an organic group having 1 to 10 carbon atoms. Examples of such organic groups include haloalkyl groups; hydrocarbon groups containing heteroatoms such as oxygen or nitrogen atoms; and hydrocarbon groups. Furthermore, when there are two or more R's in the molecule, their structures can be different or bonded together to form a cyclic structure. Considering the balance between high hydrolysis reactivity and stability during synthesis, alkoxy groups are preferred for OR', and alkylamino groups are preferred for NR'2.

[0175] Specific examples of organic groups R' include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, tert-pentyl, 2-methyl-pentyl, trifluoroethyl, trifluoromethyl, etc. Examples of NR'2 include 1-pyrrolidinyl groups, where two substituents on the nitrogen atom are bonded together to form a 5-membered ring.

[0176] As a preferred substituent X, from the viewpoint of low boiling point and stability, the organic group R' is preferably an alkyl group without heteroatoms or a fluorinated alkyl group. Furthermore, from the viewpoint of low boiling point, a lower number of carbon atoms is preferred; from the viewpoint of thermal stability and stability to moisture, a higher number of carbon atoms is preferred. Specific examples of substituent X that offer an excellent balance of these properties include OR' (tert-butoxy, tert-pentoxy, 4-methyl-2-pentoxy, trifluoroethoxy, trifluoromethoxy), and NR'2 (dimethylamino, diethylamino, methylethylamino, pyrrolidinyl, etc.). From the viewpoint of hydrolytic reactivity when used as a corrosion resist material, OR' is preferred, with dimethylamino and diethylamino being most preferred; from the viewpoint of balancing stability and reactivity, NR'2 is preferred, with tert-butoxy, tert-pentoxy, and 4-methyl-2-pentoxy being most preferred.

[0177] Furthermore, the R in the molecule can bond with the organic groups contained in the substituent X to form a cyclic structure. Examples of compounds having the structure shown below can be cited as examples.

[0178] [Chemical Formula 5]

[0179] [Structure of monoalkyltin compound (A1)]

[0180] Monoalkyl tin compounds (A1) (hereinafter sometimes referred to as "tin compounds (A1)") are not particularly limited in structure and physical properties as long as they fall within the above range. When used as EUV resist materials, the following physical properties are sometimes preferred.

[0181] (Boiling point)

[0182] As for the boiling point when using tin compounds (Al), the boiling point at 1 torr is preferably below 300°C, more preferably below 250°C, even more preferably below 200°C, and particularly preferably below 150°C. The lower limit of the boiling point at 1 torr is generally above 0°C, preferably above 10°C, and more preferably above 20°C. If the boiling point is low, distillation can be carried out at low temperatures, which is preferred from the viewpoint of easy vapor deposition when used as a photoresist material. If the boiling point is above the above-mentioned lower limit, when used as an EUV photoresist, there is a tendency for the vapor deposition and reaction processes at high temperatures to become easier, or for the volatilization and dispersion of components and released gases to be suppressed due to the excellent thermal stability of the formed film.

[0183] (molecular weight)

[0184] The molecular weight of the tin compound (Al) is preferably 500 or less, more preferably 400 or less, and even more preferably 350 or less. The lower limit is preferably 150 or more, more preferably 180 or more, and even more preferably 200 or more. If the molecular weight is too high, the boiling point may become too high, making it difficult to perform vapor deposition when used as an EUV resist. If the molecular weight is too low, the boiling point may become too low, making processes involving high-temperature vapor deposition and reactions difficult, or resulting in insufficient thermal stability of the formed film, and causing problems with the volatilization and dispersion of components and released gases.

[0185] (Molecular weight difference between organic group R and substituent X)

[0186] There are no particular limitations on the molecular weight difference between the organic group R and the substituent X, but it is preferably 50 or less, more preferably 30 or less, even more preferably 20 or less, particularly preferably 10 or less, and especially preferably 6 or less. The lower limit is 0. By reducing the molecular weight difference between R and X, there is a tendency to reduce the mass difference of various gas releases when used as a photoresist, and to make it easier to set the conditions in the EUV process. In addition, in order to control the EUV sensitivity and boiling point of tin compounds, the molecular weight difference is sometimes adjusted by changing the substituents.

[0187] On the other hand, as will be discussed later, the smaller the molecular weight difference between R and X, the smaller the molecular weight difference between the tin compound (Al) and the impurities, which sometimes makes purification more difficult.

[0188] <Tin compound (B1)>

[0189] As one embodiment of the present invention, an RSnX2Y tin compound (B1) can be cited. The RSnX2Y tin compound (B1) is defined as a compound having one organic group R, two hydrolyzable groups X capable of hydrolysis and other reactions, and one hydrolyzable group Y bonded to tetravalent tin. Specifically, it is represented by the following general formula (B1).

[0190] RSnX2Y ···(B1)

[0191] In the above general formula (B1), R is an organic group having 1 to 30 carbon atoms. Examples of such organic groups include haloalkyl groups; hydrocarbon groups containing heteroatoms such as oxygen and nitrogen atoms; and hydrocarbon groups. These can be used alone or in combination of two or more. When used as a photoresist, the gas released during detachment after exposure is a hydrocarbon. Considering minimizing the impact on the semiconductor device, a hydrocarbon group is preferred. X and Y are hydrolyzable groups with different chemical formulas. X is selected from OR', NR'2, and C≡CR', and Y is selected from OR'... Y NR' Y 2. C≡CR' Y The above R' and R' Y An organic group having 1 to 10 carbon atoms. Examples of such organic groups include haloalkyl groups; hydrocarbon groups containing heteroatoms such as oxygen and nitrogen atoms; and hydrocarbon groups, which can be used alone or in combination of two or more. Hydrocarbon groups are preferred. Where X is NR'2 and / or Y is NR'2. Y In case 2, the above R' and R' Y They can be the same or different independently. Additionally, R' and R'' in the molecule... Y In the case of two or more, the structures can be different from each other, or they can bond together to form a ring structure.

[0192] In this embodiment, a particular objective is to provide a high-performance photoresist material capable of exhibiting high purity and uniform solubility. To achieve this objective, it was discovered that when using RSnX3 as a precursor, the crystallinity of the hydrolysate can be controlled without reducing the purity of the precursor by incorporating the tin compound RSnX2Y. Furthermore, it was found that when incorporating the tin compound RSnX2Y, the tin compound RSnX2Y can be present in trace amounts or in a controlled amount. Moreover, it was discovered that RSnX2Y itself is also useful as a precursor.

[0193] The preferred structure of substituent Y is the same as the structure described in the preferred substituent X, but sometimes a combination with a specific substituent X is effective, as shown below.

[0194] The tin compound (B1) is formed by two hydrolyzable groups X and one hydrolyzable group Y, capable of undergoing hydrolysis and other reactions, and can undergo hydrolysis at non-equivalent rates. Furthermore, by controlling the hydrolysis, it is possible to preferentially react only with specific substituents X and / or Y. Additionally, four preferred combinations of substituents X and Y can be listed below.

[0195] 1) The hydrolyzable groups X and Y are NR'2 and NR' respectively. Y Case 2; (wherein, the substituent NR'2 of X and the substituent NR' of Y) Y 2 are different chemical formulas) 2) Hydrolyzable groups X and Y are OR' and OR', respectively. Y The situation; (where the substituent of X OR' and the substituent of Y OR') Y (for different chemical formulas) 3) In substituents X and Y, X is substituent NR'2 and Y is substituent OR'. Y The situation; 4) In substituents X and Y, X is a substituent OR' and Y is a substituent NR'. Y Case 2.

[0196] Regarding the tin compound mentioned in 1), from the viewpoint that the hydrolysis reaction rate is very high and the difference between the reaction rates of X and Y is small, it is preferable that X is NR'2 and Y is NR' Y The structure of 2. As a particularly preferred structure, from the viewpoint of the hydrolysis reaction rate, it is preferable that R' is a smaller alkyl group, i.e., methyl or ethyl. In addition, as shown in the case where X is NR'2 and Y is N(R')(CHNR'2), from the viewpoint of adjusting the difference in reaction rates between X and Y during hydrolysis, it is preferable that the R' in one of the substituents on N is the same as the R' contained in X.

[0197] In addition, the structure of N(R')(CH2NR'2) is preferred because it is further hydrolyzed and decomposed into easily removable low-molecular-weight components after being separated from the tin atom by hydrolysis. A specific structure corresponding to this tin compound is, for example, the structure shown below.

[0198] ·RSn(NR')2(N(R')CH2NR'2)

[0199] It should be noted that iPrSn(NMe2)2(NMeCH2NMe2) has the following characteristics: 119 Sn-NMR spectroscopy, 1 Chemical shifts in H-NMR can be used for identification and quantification.

[0200] 119Sn-NMR (223.8MHz; C6D6): δ-82ppm.

[0201] 1 H-NMR (600MHz; C6D6): δ3.37(s,2H,CH2),2.89(s,3H,Sn-NMe),2.86(s,12H,Sn-(NMe2)2),2.15(s,6H,NMe2),1.68(m,1H,iPr),1.33(s,6H,iPr).

[0202] [Chemical Formula 6]

[0203] It should be noted that when X is a dialkylamino group (NR'2) (here, R'2 is selected from methyl, primary alkyl, or secondary alkyl groups), the formation mechanism of the above compound RSn(NR')2(N(R')CH2NR'2) is not yet clear. However, it is speculated that structurally, the radical (·NR'2) generated by the removal of one of the three dialkylamino groups in the tin compound (A1) inserts into the adjacent CH bond of the nitrogen atom of another nearby compound (A1). That is, specifically, as shown in the examples, this compound can be generated by the heating- and light-based decomposition of the tin compound (A1).

[0204] Furthermore, RSn(NR')2(N(R')CH2NR'2) of the above compounds typically represents the case where R' is methyl, but in the case where R' is, for example, a primary alkyl group such as ethyl (here, R' is set as CH2R), the situation is different. 1 Compound (A1) is derived from RSnN(CH2R) 1 In the case represented by )3, compound (A4) is derived from RSn[N(CH2R 1 )2]2[N(CH2R 1 CHR 1 N(CH2R 1 )2] indicates.

[0205] Additionally, when R' is a secondary alkyl group such as isopropyl (where R' is set as RCHR) 2 R 3 ), that is, compound (A1) is composed of RSn[N(CHR 2 R 3 In the case represented by )2]3, compound (A4) is derived from RSn[N(CHR] 2 R 3 )2]2[N(CHR 2 R 3 )CR 2 R 3 N(CHR2 R 3 )2] indicates.

[0206] Regarding the tin compound in 2) above, from the viewpoints of high stability, a hydrolysis reaction rate lower than that in 1), and a small difference in the reaction rates of X and Y, it is preferable that the hydrolytic groups X and Y are OR' and OR', respectively. Y From the viewpoint of the stability of tin compounds, OR' and OR' are particularly preferred. Y These are secondary alkoxy groups (isopropoxy, 4-methyl-2-pentoxy, etc.) or tertiary alkoxy groups (tert-butyl, tert-pentyl, etc.). Furthermore, due to the resulting moderate difference in hydrolysis rates, OR' and OR'' are further preferred. Y It is a combination of secondary and tertiary groups.

[0207] Regarding the tin compound in 3) above, from the viewpoint of high hydrolysis reaction rate and large difference between the reaction rates of X and Y, it is preferable that X is substituent NR'2 and Y is substituent OR'. Y From the viewpoint of improving the hydrolytic properties of NR'2, it is preferable that R' is a smaller alkyl group, i.e., methyl or ethyl. Furthermore, from the viewpoint of the stability of tin compounds, it is preferable that OR' is [missing information]. Y The alkoxy groups are secondary alkoxy groups (isopropoxy, 4-methyl-2-pentoxy, etc.) or tertiary alkoxy groups (tert-butyl, tert-pentyl, etc.). Furthermore, by combining these preferred structures of X and Y, it is sometimes possible to increase the rate difference between the reactions of X and Y.

[0208] Regarding the tin compound in 4) above, considering its high stability, lower hydrolysis rate than in 1), and the large difference in reaction rates between X and Y, it is preferable that X is substituent OR' and Y is substituent NR'. Y 2. From the viewpoint of the stability of tin compounds, OR' is preferably a secondary alkoxy (isopropoxy, 4-methyl-2-pentoxy, etc.) or a tertiary alkoxy (tert-butyl, tert-pentyl, etc.). To improve NR'... Y From the perspective of the hydrolytic properties of 2, R' is preferred. Y The alkyl group is either a smaller alkyl group, i.e., methyl or ethyl. Furthermore, by combining preferred structures of these X and Y, it is sometimes possible to increase the rate difference between the reactions of X and Y.

[0209] [Monoalkyltin compositions comprising tin compounds (A1) and (B1)]

[0210] RSnX3 and RSnX2Y can be hydrolyzed separately to form tin hydrolysates. In particular, to control crystallinity without reducing the purity of the obtained tin hydrolysates, a mixture containing tin compound (A1) and tin compound (B1) is preferred. That is, importantly, tin compound (A1) and tin compound (B1) have the same organic group R, and the organic group R remaining in the tin hydrolysate after hydrolysis is substantially equivalent. This differs from impurities (R2SnX2(A2), SnX4(A3), etc.) contained in monoalkyltin compounds with structures different from tin compound (B1). In other words, the effects of the present invention are more effectively obtained when the organic group R contains only a single chemical structure in the tin compound.

[0211] Compositions containing tin compounds (A1) and (B1) are referred to as monoalkyltin compositions (A1B1).

[0212] The specific composition of the monoalkyl tin composition (A1B1) containing tin compounds (A1) and (B1) corresponds to the composition of tin compounds (A1) and (B1) in the tin hydrolysate.

[0213] The composition of tin compounds (A1) and (B1) in the monoalkyltin composition (A1B1) is not particularly limited. From the viewpoint of obtaining high-purity tin hydrolysate, it is preferable to include a high-purity tin compound (A1) as the main component and also to include a tin compound (B1). That is, in this composition, both the purity and crystallinity of the tin hydrolysate can be controlled.

[0214] The content (purity) of tin compound (Al) in the monoalkyltin composition (AlB1) is preferably 50 mol% to 99.99 mol%, with a lower limit of more preferably 55 mol% or more, further preferably 60 mol% or more, particularly preferably 65 mol% or more, and especially preferably 70 mol% or more. The upper limit is more preferably 99 mol% or less, further preferably 97 mol% or less, particularly preferably 95 mol% or less, and especially preferably 90 mol% or less.

[0215] On the other hand, the content (purity) of tin compound (B1) in the monoalkyltin composition (A1B1) is preferably 0.01 mol% or more and less than 50 mol%, with a lower limit more preferably 0.1 mol% or more, further preferably 0.5 mol% or more, particularly preferably 1 mol% or more, especially preferably 3 mol% or more, and even more preferably 5 mol% or more. The upper limit is more preferably 30 mol% or less, further preferably 25 mol% or less, particularly preferably 20 mol% or less, and even more preferably 15 mol% or less.

[0216] Furthermore, from the viewpoint of further reducing crystallinity and obtaining tin hydrolysates with higher solubility, a monoalkyltin composition is preferred, which is a tin compound (B1) as the main component and also contains a tin compound (A1). The content (purity) of the tin compound (B1) in the monoalkyltin composition (A1B1) is preferably 50 mol% to 99.99 mol%, more preferably 55 mol% or more, further preferably 60 mol% or more, particularly preferably 65 mol% or more, and especially preferably 70 mol% or more.

[0217] The upper limit is more preferably 99 mol% or less, further preferably 97 mol% or less, particularly preferably 95 mol% or less, and especially preferably 90 mol% or less.

[0218] On the other hand, the content (purity) of tin compound (Al) in the monoalkyltin composition (AlB1) is preferably 0.01 mol% or more and less than 50 mol%, with a lower limit more preferably 0.1 mol% or more, further preferably 0.5 mol% or more, particularly preferably 1 mol% or more, especially preferably 3 mol% or more, and particularly preferably 5 mol% or more. The upper limit is more preferably 30 mol% or less, further preferably 25 mol% or less, particularly preferably 20 mol% or less, and especially preferably 15 mol% or less.

[0219] Furthermore, the total content of tin compounds (A1) and (B1) in the monoalkyltin composition (A1B1) is preferably 80 mol% or more, more preferably 85 mol% or more, and even more preferably 90 mol% or more. The upper limit is 100 mol%. By having a sufficiently high total content of tin compounds (A1) and (B1), a tin hydrolysate with high purity can be obtained.

[0220] <Impurities>

[0221] [Tin compounds as impurities]

[0222] The monoalkyl tin composition (A1B1) of one embodiment of the present invention may contain impurities. There are no particular limitations on the tin compounds other than the aforementioned tin compounds (A1) and (B1) that are impurities; however, tin compounds (A2) and (A3) can be listed as representative impurities. Tin compounds (A2) and (A3) are difficult to separate because their structures and boiling points are similar to those of tin compound (A1), making them difficult to separate by distillation. Furthermore, they are produced during reactions, heating, etc., through the decomposition of tin compound (A1).

[0223] ·R2SnX2 ····(A2)

[0224] SnX4 ····(A3)

[0225] Especially when the boiling points of tin compound (A1) and tin compound (A2) or (A3) are close, as shown below, separation by distillation is often difficult, and suppression during reaction and post-processing becomes important. Regarding examples containing impurities with similar boiling points, namely tin compounds (A2) and (A3), it is preferable to suppress the content of tin compounds (A2) and (A3) after the reaction. The amount of tin compounds (A2) and (A3) contained in the synthetic tin compound (crude product) after the reaction is preferably 3 mol% or less, more preferably 2 mol% or less, further preferably 1 mol% or less, particularly preferably 0.5 mol% or less, especially preferably 0.3 mol% or less, and even more preferably 0.1 mol% or less, 0.05 mol% or less, and 0.03 mol% or less.

[0226] (Boiling point of impurities)

[0227] The boiling point here is not limited to atmospheric pressure, but refers to the boiling point when compared under the same pressure, especially under the pressure during distillation. A close difference in boiling points means that the difference between the boiling points of tin compounds (A1) and (A2) is typically 50°C or less, preferably 30°C or less, more preferably 10°C or less, and even more preferably 5°C or less. The lower limit is 0°C.

[0228] Furthermore, when the molecular weights of R and X are close, the difference in boiling points is also close, or the intermolecular interactions become stronger, making separation difficult in most cases. The situation where the difference in molecular weights of R and X is close refers to a difference that is typically 30 or less, preferably 20 or less, more preferably 10 or less, and even more preferably 5 or less. The lower limit is 0.

[0229] As an example, the molecular weight difference between iPrSn(NMe2)3 (A1-1) and iPr2Sn(NMe2)2 (A2-1) is small (294 g / mol and 293 g / mol, respectively). The difference is only 1 g / mol, and since isopropyl and dimethylamino groups have very similar polarities, the boiling point difference between the tin compounds (A1-1) and (A2-1) is extremely small. Boiling point measurements of these compounds show a difference of less than 2 °C within a pressure range of 0.7–10 torr. Therefore, to obtain high-purity tin compound (A1-1), distillation with high separation capabilities is required.

[0230] The decomposition of tin compounds (A1) and their precursor tin compounds (hereinafter sometimes referred to as "starter tin compounds") (E1) due to side reactions during the reaction and subsequent post-processing steps becomes a problem. For example, there are sometimes disproportionation reactions between tin compounds (A1) and (E1) as shown in the following formula, which can be accelerated or inhibited by various reaction conditions.

[0231] In addition, sometimes light-based decomposition reactions occur, or the decomposition reaction is accelerated by light and heat. Furthermore, the presence of trace amounts of air, moisture, etc., can sometimes promote decomposition.

[0232] (Decomposition of tin compounds)

[0233] [Chemical Formula 7]

[0234] Sometimes it also contains divalent tin compounds, SnX2 (A8). In the case where the tin compound (A1) is RSn(NR2)3, the following tin compounds (A8-1) can be listed.

[0235] ·Sn(NR'2)2····(A8-1)

[0236] From the viewpoint of producing a high-purity photoresist material, the content of tin compound A8 is preferably 1.0 mol% or less, more preferably 0.5 mol% or less, even more preferably 0.1 mol% or less, and particularly preferably 0.01 mol% or less, relative to the content of the synthetic tin compound in terms of tin atoms. The lower limit is 0 mol%.

[0237] In addition, depending on the raw materials and manufacturing methods used, impurities such as R3SnX and R4Sn, which are tin compounds with more hydrocarbon groups, may also be mixed in as impurities.

[0238] As one embodiment of the present invention, it can be obtained by using two or more monoalkyltin compounds and / or compounds containing two or more organic groups R in one molecule of a monoalkyltin compound as raw materials and performing conventional hydrolysis.

[0239] (A mixture of two or more organic groups R)

[0240] This tin hydrolysate contains an organic group R, which may have two or more substituents. For example, the substituents occupying the majority of the substituent R may sometimes have two different substituents R. A and R B (It should be noted that the substituent R that accounts for the largest proportion is set as R.) A The substituent that accounts for the second largest proportion is set as R. B It may also contain substituents R. A and R B (Other substituents). As the organic group R, a hydrocarbon group is preferred. As the substituent R... A and R B The structure, as long as it is selected from the range of R above and R A With R B There are no particular restrictions depending on the structure; in the case of primary hydrocarbon R... 1secondary hydrocarbon group R 2 tertiary hydrocarbon group R 3 In selecting the range, to achieve the best balance between sensitivity stability, R A and R B The structures are preferably selected from different ranges. As a particularly preferred combination, "R" is preferred. A : Primary hydrocarbon group / R B : Tertiary hydrocarbon group R 3 “R” A : secondary hydrocarbon group / R B : Tertiary hydrocarbon group R 3 To achieve a balance between sensitivity and hydrophobicity, "R" is further specifically preferred. A : secondary hydrocarbon group / R B : Tertiary hydrocarbon group R 3 Furthermore, considering the performance balance of the resist material, "R" is particularly preferred. A : secondary hydrocarbon group / R B : Tertiary hydrocarbon group R 3 The combination of "".

[0241] (Cyclic hydrocarbon group)

[0242] Regarding hydrocarbon groups, if it contains a cyclic hydrocarbon group R c The deformation of the ring-shaped skeleton increases its reactivity during exposure, which is sometimes preferable from the viewpoint of resist sensitivity. R is a preferred option. c Examples of cyclic skeletons contained therein include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. Furthermore, groups having an alkyl group such as a methyl group at the 1-position (the carbon bonded to Sn) are sometimes preferred, and are therefore preferred examples such as 1-methyl-cyclopropyl, 1-methyl-cyclobutyl, 1-methyl-cyclopentyl, 1-methyl-cyclohexyl, and 1-methyl-cycloheptyl. The cyclic hydrocarbon group R in the hydrocarbon group... c There is no particular limitation on the proportion, but the upper limit is preferably 50 mol% or less, more preferably 40 mol% or less, further preferably 35 mol% or less, and particularly preferably 30 mol% or less. The lower limit is preferably 1 mol% or more, more preferably 5 mol% or more, further preferably 10 mol% or more, and particularly preferably 15 mol% or more.

[0243] (A hydrocarbon group with an unsaturated bond)

[0244] Regarding hydrocarbon groups, if it contains a hydrocarbon group R with an unsaturated bond... u During exposure, the unsaturated bonds react or polymerize, causing structural changes, which is sometimes preferable from the perspective of resist sensitivity. A preferred option is a hydrocarbon group R with unsaturated bonds. uExamples of skeletons containing unsaturated bonds include alkenes, alkynes, dienes, trienes, benzenes, etc. From the viewpoint of reactivity and stability, alkenes are preferred, and from the viewpoint of reactivity, terminal alkenes are preferred. Specific preferred examples include vinyl, 1-propenyl, allyl, 3-butenyl, 4-pentenyl, etc. From the viewpoint of resist sensitivity, vinyl, 1-propenyl, and allyl alkenes close to the Sn atom are preferred. From the viewpoint of stability, unsaturated bonds separated from the Sn atom by two or more carbon atoms are preferred. From a balance perspective, allyl and 3-butenyl are preferred. The cyclic hydrocarbon group R in the hydrocarbon group... c There is no particular limitation on the proportion, but the upper limit is preferably 50 mol% or less, more preferably 40 mol% or less, further preferably 35 mol% or less, and particularly preferably 30 mol% or less. The lower limit is preferably 1 mol% or more, more preferably 5 mol% or more, further preferably 10 mol% or more, and particularly preferably 15 mol% or more.

[0245] (Preferred R) A With R B (Composition ratio)

[0246] As the preferred R A With R B The composition ratio, with the most abundant hydrocarbon group designated as "R" A The second most common hydrocarbon group is designated as "R". B In the case of "R", A The content of [substituent name] is preferably 50 mol% or more, more preferably 60 mol% or more, and even more preferably 70 mol% or more. The upper limit is preferably 99 mol% or less, more preferably 95 mol% or less, and even more preferably 90 mol% or less. If the hydrocarbon group R occupies a major proportion of the hydrocarbon group... A Within the aforementioned range, it is possible to achieve this without harming R. A By appropriately controlling crystallization during hydrolysis while maintaining the performance of the resist material, a tin compound with moderate crystallinity is provided. R is a preferred option. B The content of [specific ingredient] is preferably 50 mol% or less, more preferably 40 mol% or less, further preferably 35 mol% or less, and particularly preferably 30 mol% or less. The lower limit is preferably 1 mol% or more, more preferably 5 mol% or more, further preferably 10 mol% or more, and particularly preferably 15 mol% or more. In R B Within the aforementioned range, it is sometimes possible to achieve R without compromising its composition. A In the case of performance, give R B The properties of tin, or tin compounds with moderate crystallinity, can be obtained.

[0247] As R A Preferred secondary hydrocarbon group R2 Of which is preferably isopropyl. Additionally, as R... B Preferred tertiary hydrocarbon group R 3 cyclic hydrocarbon group R c Hydrocarbon group R with unsaturated bond u Any of the following, tertiary hydrocarbon group R 3 In this group, tert-butyl is preferred. Cyclic hydrocarbon group R c In this context, methylcyclopentyl is preferred. The hydrocarbon group R has an unsaturated bond. u In this case, butenyl is preferred.

[0248] <Method for manufacturing tin compound (A1)>

[0249] There is no particular limitation on the method for manufacturing tin compound (A1), and it can be manufactured by methods known in the past. Specifically, as a method for manufacturing a tin compound containing tin compound (A1) as the main component for the purpose of obtaining tin compound (A1), the following manufacturing methods can be listed as examples.

[0250] (Manufacturing Method 1)

[0251] As an example of a method for producing tin compound (A1), the following method can be described: a raw tin compound (E1) and a reactant ((M1) or (M2)) are reacted under specific conditions in an organic solvent (S1), thereby synthesizing a synthetic tin compound (A1). The following is a detailed description; in this manufacturing method, a typical reaction formula is shown below.

[0252] RSnY E 3(E1)+3MX(M1)→RSnX3(A1)+3MY E

[0253] This manufacturing method 1 can process the tin compound RSnY as a raw material. E 3. Purification can improve the purity and yield high-purity RSnX3(A1), which is preferred in this respect. In addition, from the viewpoint of using tin compounds with pre-introduced organic groups R as raw materials, it is possible to reduce the presence of tin compounds A2, A3, A4, etc., as impurities, and to reduce impurities that are difficult to separate during distillation, compared with other methods.

[0254] The following describes the material composition and other aspects used in the manufacturing method of tin compound (Al).

[0255] [Reference Tin Compound (E1)]

[0256] The raw material tin compound (E1) is represented by the following formula.

[0257] ·RSnYE 3 ···(E1)

[0258] (In general formula (E1), R is an organic group having 1 to 30 carbon atoms. Examples of such organic groups include haloalkyl groups; hydrocarbon groups containing heteroatoms such as oxygen and nitrogen atoms; and hydrocarbon groups. Y) E Selected from halogen atoms, OR', and NR'2. R' can be the same or different, and is an organic group with 1 to 10 carbon atoms that can be substituted by halogens. Furthermore, when there are two or more R's in a molecule, their structures can be different from each other, or they can be bonded together to form a cyclic structure.

[0259] The organic group Y in the reaction formula E There are no restrictions on the structure as long as the organic group is substituted by the reactant (M1). As a preferred specific example, the organic group is selected from halogen atoms, OR', and NR'2. Among them, halogen atoms have high reactivity and are therefore preferred. Among them, Cl atoms have a good balance between stability and reactivity, are easy to purify by distillation, and are easy to prepare raw tin compounds (E1) with higher purity, and are therefore preferred. Among them, monoalkyltin chloride is the most preferred.

[0260] raw material tin compound RSnY E 3. Purity can be improved through purification. From the perspective of fewer residual impurities and increased high-purity tin compounds (Al), high-purity RSnY is preferred. E 3 is used as a raw material. Specifically, in terms of tin atoms, it is typically 95 mol% or more, preferably 97 mol% or more, more preferably 99 mol% or more, even more preferably 99.5 mol% or more, and particularly preferably 99.9 mol% or more. The upper limit is 100 mol%.

[0261] On the other hand, tin compounds and moisture, as impurities, can sometimes help prevent the crystallization of the target material and other stabilization processes, or affect the reaction of synthesizing tin compounds (Al). Sometimes it is preferable to contain 0.1 mol% or more of tin compounds as impurities, sometimes more preferably 0.2 mol% or more, and even more preferably 0.3 mol% or more.

[0262] Specifically, R2SnY E 2. R3SnY E The content of R2SnY, calculated in terms of tin atoms, is preferably 3 mol% or less, more preferably 2 mol% or less, even more preferably 1 mol% or less, and particularly preferably 0.1 mol% or less. On the other hand, from the viewpoint of helping to prevent stabilization such as crystallization of the target material, R2SnY is sometimes preferred. E 2. R3SnY E R4Sn contains 0.01 mol% or more, and sometimes more preferably 0.1 mol% or more.

[0263] [Reactant (M1)]

[0264] The reactant (M1) is a tin compound (E1)(RSnY) that can react with the raw material. E 3) Organic group Y E The reactant is capable of undergoing a substitution reaction and generating the tin compound (A1) (RSnX3) as the target. Preferred structures for the reactant (M1) include MX, MX2, MX3, etc. For example, when the reactant (M1) is MX, the theoretical reaction formula is as follows.

[0265] ·RSnY E 3(E1)+3MX(M1)→RSnX3(A1)

[0266] In the reaction formula, M represents a metal atom from Group 1, Group 2, Group 12, or Group 13. When M is from Group 1, it is sometimes represented as "MX"; when M is from Group 2 or Group 12, it is sometimes represented as "MX2"; and when M is from Group 13, it is sometimes represented as "MX3". The two or more X's in the molecule can also be different. Furthermore, X is as described above. Specifically, when X is OR', examples include LiOR', NaOR', KOR', MgOR'2, and ZnOR'2. From the viewpoint of high reactivity, LiOR', NaOR', and KOR' are preferred. When X is NR'2, LiNR'2, NaNR'2, KNR'2, Mg(NR'2)2, Zn(NR'2)2, etc. can be listed. From the viewpoint of high reactivity, LiNR'2, NaNR'2, and KNR'2 are preferred. From the viewpoint of stability, Mg(NR'2)2 and Zn(NR'2)2 are preferred. Among them, from the viewpoint of ease of preparation of high-purity reagents, LiNR'2 (aminolithium: dimethylaminolithium, diethylaminolithium, etc.) is the most preferred.

[0267] [Reactant (M2)]

[0268] The reactant (M2) refers to a compound selected from reactant (M1) or a compound represented by the chemical formula HX. H represents a hydrogen atom, and X has the same meaning as the X contained in the tin compound (A1). Examples of compounds equivalent to HX include HOR' (methanol, ethanol, tert-butanol, 4-methyl-2-pentanol, etc.) and HNR'2 (dimethylamine, diethylamine, morpholine, etc.). From the viewpoint of reactivity, compounds selected from reactant (M1) are preferred in reactant (M2) due to their high reactivity. From the viewpoint of preventing the introduction of metals after the reaction, compounds equivalent to HX, namely HOR' (methanol, ethanol, tert-butanol, 4-methyl-2-pentanol, etc.) and HNR'2 (dimethylamine, diethylamine, morpholine, etc.), are preferred, especially when the starting material tin compound (E1) (RSnY) is used. E3)Y E When the highly reactive NR'2 is used, it is sometimes possible to provide a high-purity product without the inclusion of metals if a compound equivalent to HX is used.

[0269] (Amounts of reactants (M1) and (M2))

[0270] The lower limit of the molar equivalent is preferably 3.00 eq or more, more preferably 3.03 eq or more, and most preferably 3.06 eq or more, relative to the raw material tin compound (E1).

[0271] The upper limit is preferably 10.00 eq or less, more preferably 8.00 eq or less, and even more preferably 7.00 eq or less. In addition, sometimes two or more reactants (M1) and (M2) are used together. In this case, the total molar equivalents of the reactants preferably fall within this range.

[0272] (Preparation method of reactant (M1))

[0273] Regarding the temperature of the step in preparing the reactant (M1), the preferred lower limit temperature is preferably about -78°C or higher, more preferably about -40°C or higher, even more preferably about -20°C or higher, particularly preferably about -10°C or higher, and especially preferably -5°C or higher. The upper limit temperature is preferably about 40°C or lower, more preferably about 20°C or lower, and even more preferably about 15°C or lower. Especially when the reactant (M1) is lithium amide, it needs to be prepared from amine and alkyl lithium. If the temperature is too high, the amine tends to volatilize, or the decomposition of the alkyl amide is accelerated. In addition, if the temperature is too low, the solubility of dimethylamide in the solvent tends to decrease, and the viscosity of the latter increases, making it difficult to stir.

[0274] The reaction time following the dropwise addition of the reactant (M1) is preferably 0.5 hours or more (sometimes referred to as "h" in "hours"), more preferably 1 hour or more, and even more preferably 2 hours or more. The upper limit is preferably 48 hours or less, more preferably 30 hours or less, and even more preferably 20 hours or less. If the above reaction time is too short, the reactant (M1) may not be of sufficient purity, or in the case of a slurry, insufficient mixing may result in an unevenly mixed reactant (M1). Conversely, if the above reaction time is too long, byproducts may be generated due to the decomposition of the reactant (M1), or the stoichiometric amount may decrease.

[0275] In addition, from the perspective of maintaining the purity of the reactant (M1) or controlling the moisture content in the reactant (M1), it is preferable to continue stirring after the preparation of the reactant (M1) and use the reactant (M1) in this reaction during a period of 3 to 48 hours after preparation.

[0276] (Preparation method of reactant (M2))

[0277] Reagent (M2) refers to a compound selected from reactant (M1) or a compound represented by the chemical formula HX. The preparation method of reactant (M1) is as described above. Regarding the compound represented by the chemical formula HX, the following applies. Commercially available compounds of the chemical formula HX can be used directly; however, to avoid the introduction of impurities, moisture, or metals, it is preferable to use compounds that have undergone purification operations such as distillation, adsorption, or column chromatography. Alternatively, commercially available products have undergone purification operations such as semiconductor grade (EL grade) or dehydration grade. Specifically, the purity, on a mass basis, is preferably 95% or more, more preferably 98% or more, further preferably 99% or more, particularly preferably 99.99% or more, and especially preferably 99.99% or more. The upper limit is 100%. Preferred organic solvents for preparation are as shown in the following organic solvent (S1). Specifically, the amount of metal contamination, on a mass basis, is preferably 100 ppm or less for each metal element, more preferably 10 ppm or less, further preferably 1 ppm or less, especially preferably 100 ppb or less, and especially preferably 10 ppb or less. The lower limit is 0 ppb.

[0278] [Organic solvent (S1)]

[0279] In this manufacturing method, a tin compound (E1), a reactant ((M1) or (M2)), and an organic solvent (S1) are used. The organic solvent (S1) is not particularly limited, but preferably includes, for example, hydrocarbon solvents (hexane, cyclohexane, heptane, decane, decahydronaphthalene, etc.), aromatic solvents (benzene, toluene, xylene, anisole, etc.), ether solvents (THF (tetrahydrofuran), diethyl ether, TBME (tert-butyl methyl ether), dibutyl ether, 3-methylTHF, THP (tetrahydropyran), 3-methylTHP, etc.), ketone solvents (acetone, MEK (methyl ethyl ketone), MIBK (methyl isobutyl ketone), etc.), amide solvents (DMF (N,N-dimethylformamide), DMAC (N,N-dimethylacetamide), etc.), ester solvents (ethyl acetate, butyl acetate, etc.), and alcohol solvents (methanol, ethanol, isopropanol, butanol, 4-methyl-2-pentanol, etc.). Aromatic, hydrocarbon, and ether solvents that do not readily react with the reactant are preferred. These solvents can be used alone or in combination of two or more.

[0280] The solvent is preferably one that does not contribute to the presence of metallic contaminants.

[0281] Hydrocarbons and aromatics, particularly those with low solubility in inorganic salts and readily removable byproducts such as inorganic salts after the reaction via filtration or centrifugation, are especially preferred solvents. Toluene and hexane are currently the most preferred solvents for easy removal of products under low temperature and vacuum after the reaction. On the other hand, ethers are preferred solvents for facilitating the reaction due to the high solubility of organometallic reactants such as lithium dimethylamino. In other words, combining two or more solvents, such as hydrocarbons, aromatics, and ethers, can sometimes combine the advantages of these solvents. Furthermore, when using HOR' (methanol, ethanol, tert-butanol, 4-methyl-2-pentanol, etc.) or HNR'2 (dimethylamine, diethylamine, morpholine, etc.) as reactants (M2), reactant (M2) sometimes also functions as a solvent.

[0282] (Manufacturing Method 2)

[0283] As an example, it is synthesized using SnX4, a tin compound, as a raw material, and RM or RMZ, a reactant containing R.

[0284] SnX4+RM→RSnX3+MX

[0285] SnX4+RMZ → RSnX3+MXZ E

[0286] In the above reaction formula, M represents a metal atom or a hydrogen atom from Group 1, Group 2, Group 12, or Group 13. When M is Group 1 or a hydrogen atom, it is sometimes represented as "RM"; when M is Group 2 or Group 12, it is sometimes represented as "RMZ". E When M is a family of 13, it is sometimes represented as "RMZ". E 2”, the two or more X’s in the molecule can also be different. Z E Represents a halogen atom or R. Two or more Z atoms in a molecule. E They can also be different. Additionally, X is as described above. Specifically, when X is OR', examples include ROH, RLi, RNa, RK, and RMGZ. E 、RZnZ E From the perspective of high reactivity, RLi is preferred; from the perspective of reactivity selectivity of monoalkylation, low basicity, and prevention of decomposition of the target analyte, RMgZ is preferred. E 、RZnZ E Among these, RMgZ is particularly preferred. Furthermore, from the viewpoint of not contaminating metals, ROH is preferred.

[0287] From the perspective of the reaction mechanism, this method has the problem of introducing byproducts with two or more organic groups R. Regarding this, the structure of RSnX3(A1) that is effective for this method is a structure where the organic group R is a tertiary alkyl group (e.g., tert-butyl, tert-pentyl, 1-methyl-cyclopentyl, 1-methyl-cyclohexyl). In this case, considering the ease of controlling the reactivity of the reactant RM and the difficulty of introducing two or more large tertiary alkyl groups onto the Sn atom, it tends to yield a good yield of the target product selectively added to one alkyl group. Furthermore, the fact that the boiling points of byproducts with two or more organic groups R differ significantly from those of the target product, making them easier to separate by distillation, also contributes to the effectiveness of this method.

[0288] (Manufacturing Method 3)

[0289] As an example, it includes step α, which involves producing MSnX3 from SnX2, a monoalkyltin compound used as a raw material, and a reactant containing MX, and then reacting the resulting MSnX3 with an alkylating agent RZ. F The reaction process β is a method.

[0290] SnX2+MX→MSnX3 (Process α)

[0291] MSnX3+RZ F →RSnX3 (Process β)

[0292] In the reaction formula, M represents a metal atom from Group 1, Group 2, Group 12, or Group 13. When M is from Group 1, it is sometimes represented as "MX"; when M is from Group 2 or Group 12, it is sometimes represented as "MX2"; and when M is from Group 13, it is sometimes represented as "MX3". Two or more X's in the molecule can also be different. Furthermore, X is as described above. Specifically, when X is OR', examples include LiOR', NaOR', KOR', MgOR'2, ZnOR'2, etc., with LiOR', NaOR', and KOR' being preferred from the viewpoint of high reactivity. When X is NR'2, examples include LiNR'2, NaNR'2, KNR'2, Mg(NR'2)2, Zn(NR'2)2, etc., with LiNR'2, NaNR'2, and KNR'2 being preferred from the viewpoint of high reactivity. Among these, LiNR'2 is the most preferred from the perspective of ease of preparing high-purity reagents. In the alkylating agent RZ... F In the middle, Z F The atoms are halogen atoms (F, Cl, Br, I), among which Br and I are preferred from the viewpoint of reactivity.

[0293] Starting from the reaction form, this method has the ability to synthesize or obtain alkyl halides, i.e., RZ. FAdvantages of introducing an organic group R. This is effective when applied to manufacturing methods 1 or 2, especially when the organic group R is unstable and causes decomposition or side reactions. Specifically, it is sometimes effective when the organic group R has heteroatoms, unsaturated bonds, aromatic rings, etc.

[0294] (Distillation purification)

[0295] Synthesized tin compounds (Al) (crude products) are sometimes further purified by distillation. The substance obtained by distillation and purification of the crude product is called "purified tin compound".

[0296] The higher the proportion of tin compound (Al) in the purified tin compound, the better the performance of the resist. Therefore, the purity of the tin compound (Al) is preferably 96 mol%, more preferably 97 mol%, further preferably 98 mol% or more, particularly preferably 99 mol% or more, especially preferably 99.2 mol% or more, particularly preferably 99.5 mol% or more, even more preferably 99.8 mol% or more, and most preferably 99.9 mol% or more. On the other hand, if the purity of the triaminotin compound is too high, it may decompose or become unstable during storage or use due to the disproportionation reaction of the organic group R of the tin compound (Al). In this case, it is preferable to be 100.0 mol% or less, more preferably 99.9 mol% or less.

[0297] For use as a photoresist material, the inorganic impurities in the purified tin compound are preferably low. Specifically, the elemental concentration of each inorganic impurity is preferably 10 ppm or less, more preferably 1 ppm or less, even more preferably 0.1 ppm or less, and particularly preferably 0.01 ppm or less.

[0298] It should be noted that when the purified tin compound does not reach sufficient quality, other purification processes are sometimes performed before and after distillation (purification using filtration or column chromatography, addition of adsorbents, reactants, etc.).

[0299] <Method for manufacturing tin compound (B1)>

[0300] There are no particular limitations on the method for manufacturing tin compound (B1), and it can be manufactured by methods known in the past. As a preferred manufacturing method, the following manufacturing methods similar to "method 1 for manufacturing tin compound (A1)" can be listed as examples.

[0301] As a first manufacturing method (B1 manufacturing method 1), a monoalkyltin compound RSnX3 (A1) and a reactant (M1Y or M2Y) containing an equivalent amount of Y are reacted under specific conditions in an organic solvent (S1) (or solvent-free if necessary) to obtain a tin compound (B1). It should be noted that reactants M1Y and M2Y, as described below, are reactants in which the substituent X in reactants M1 and M2 described in the above-described manufacturing method of the monoalkyltin compound RSnX3 (A1) is replaced with Y.

[0302] In manufacturing method 1 of B1, if a typical reaction formula is listed, it takes the form shown below.

[0303] • RSnX3(A1)+MY(M1Y or M2Y)→RSnX2Y(B1)+MX

[0304] (X is selected from OR', NR'2, C≡CR', Y is selected from OR') Y NR' Y 2. C≡CR' Y )

[0305] As a second manufacturing method (B1 manufacturing method 2), a monoalkyltin compound RSnY3 and a reactant (M1 or M2) containing an equivalent of 2 equivalents of X are reacted under specific conditions in an organic solvent (S1) (or a solvent-free solvent if necessary) to obtain a tin compound (B1).

[0306] In manufacturing method 2 of B1, if a typical reaction formula is listed, it takes the form described below.

[0307] ·RSnY3+2MX(M1 or M2)→RSnX2Y(B1)+2MY2

[0308] The structure of the monoalkyltin compound RSnX3(A1) used as a raw material in the reaction formula of method 1 for manufacturing B1 is not particularly limited, but X is preferably NR'2, based on the high reactivity of the above reaction. By making the reactivity high, as described above, it is possible to selectively react only the reactants MY and MY1 in equivalent amounts, and it is possible to obtain RSnX2Y(B1) with high purity.

[0309] The structure of the monoalkyltin compound RSnY3 used as a raw material in manufacturing method 2 of B1 is not particularly limited, but considering the high reactivity of the above reaction, Y is preferably NR'. Y 2. By making the reactivity high, as described above, it is possible to selectively react only an equivalent amount of the reactant MX2, and thus obtain RSnX2Y(B1) with high purity.

[0310] The tin compounds RSnX3(A1) and RSnY3, which are raw materials for various manufacturing methods, can have their purity improved through purification. Using high-purity RSnX3(A1) and RSnY3 as raw materials results in fewer residual impurities and an increase in the purity of the tin compound (B1), which is preferable from this perspective. Specifically, the purity is typically 95 mol% or more, preferably 97 mol% or more, more preferably 99 mol% or more, further preferably 99.5 mol% or more, and particularly preferably 99.9 mol% or more, based on tin atoms. The upper limit is 100 mol%.

[0311] On the other hand, tin compounds and moisture, as impurities, can sometimes help prevent the crystallization of the target product or affect the reaction of synthesizing tin compound (B1). Sometimes it is preferable to contain 0.1 mol% or more of tin compounds as impurities, sometimes more preferably 0.2 mol% or more, and even more preferably 0.3 mol% or more.

[0312] Specifically, R2SnX2, R3SnX, and R4Sn are preferably 3 mol% or less, more preferably 2 mol% or less, even more preferably 1 mol% or less, and particularly preferably 0.1 mol% or less, respectively, based on the conversion of tin atoms. On the other hand, from the viewpoint of helping to prevent stabilization such as crystallization of the target product, R2SnX2, R3SnX, and R4Sn are sometimes preferably contained in amounts of 0.01 mol% or more, and sometimes more preferably 0.1 mol% or more.

[0313] [Reactant (M1Y)]

[0314] The reactant (M1Y) is capable of undergoing a substitution reaction with the substituent X of the tin compound RSnX3 (A1) of the starting material to generate the tin compound (B1) (RSnX2Y) as the target product. A reactant having moderate reactivity that allows for selective reaction with only 1 equivalence is particularly preferred. Examples of structures for the reactant (M1Y) include MY, MY2, and MY3.

[0315] In the reaction formula, M represents a metal atom from Group 1, Group 2, Group 12, or Group 13. When M is Group 1, it is sometimes represented as "MY"; when M is Group 2 or Group 12, it is sometimes represented as "MY2"; and when M is Group 13, it is sometimes represented as "MY3". The two or more Y atoms in the molecule can also be different. Furthermore, Y is as described above. Specifically, when Y is OR' Y At that time, LiOR' can be listed Y NaOR' Y 、KOR' Y MgOR' Y 2. From the perspective of high reactivity, ZnOR'2, etc., are preferred over LiOR', NaOR', and KOR'. When X is NR' YWhen it is 2, LiNR’ can be listed Y 2. NaNR’ Y 2. KNR’ Y 2. Mg(NR’ Y 2)2, Zn(NR’ Y 2)2, etc. From the viewpoint of high reactivity, LiNR’ is preferred Y 2. NaNR’ Y 2. KNR’ Y 2. From the viewpoint of stability, Mg(NR’ Y 2)2, Zn(NR’ Y 2)2 are preferred. Among them, from the viewpoint of ease of preparation of high-purity reagents, LiNR’ Y 2 (lithium amides: lithium dimethylamide, lithium diethylamide, etc.) is most preferred.

[0316] [Reagent (M2Y)]

[0317] The reagent (M2Y) represents a compound selected from the reagents (M1Y) or a compound represented by the chemical formula HY. H is a hydrogen atom, and Y has the same meaning as Y contained in the tin compound (B1). As the compound corresponding to HY, HOR’ Y (methanol, ethanol, tert-butanol, 4-methyl-2-pentanol, etc.), HNR’ Y 2 (dimethylamine, diethylamine, morpholine, etc.) can be listed. Among the reagents (M2Y), from the viewpoint of reactivity, the compounds selected from the reagents (M1Y) have high reactivity, so they are preferred. From the viewpoint of not mixing metals after the reaction, compounds corresponding to HY, that is, HOR’ Y (methanol, ethanol, tert-butanol, 4-methyl-2-pentanol, etc.), HNR’ Y 2 (dimethylamine, diethylamine, morpholine, etc.) are preferred.

[0318] <Reaction conditions of Production Method 1 of B1>

[0319] As Production Method 1 of B1, a monoalkyltin compound RSnX3 (A1) and a reagent (M1Y or M2Y) containing 1 equivalent of Y react in an organic solvent (S1) (or solvent-free as required) under specific conditions to obtain the tin compound (B1). As the reaction conditions, the content described in "Production Method 1 of Tin Compound (A1)" can also be referred to.

[0320] In particular, as the X group of the raw material tin compound RSnX3, from the viewpoints of the selectivity and reactivity of 1-equivalent addition, an OR' group or an NR'2 group is preferably used, and from the viewpoint of reactivity, NR'2 is preferred. On the other hand, from the viewpoints of the combination with the reactant and selectivity, an OR' group is sometimes preferred. In addition, as the reactant, a reactant having a HY structure can sometimes provide a high-purity product without mixing in a metal, and thus is preferred, especially effective when the X group of the raw material tin compound RSnX3 is a highly reactive OR' group or NR'2 group. In particular, among reactants having a HY structure, secondary alcohols and tertiary alcohols (isopropyl alcohol, tert-butyl alcohol, 4-methyl-2-pentanol, etc.) have a high selectivity for 1-equivalent reaction due to steric hindrance, and thus are preferred. Similarly, when RSnX3 is stored in a state mixed with a reactant having a HY structure, this reaction sometimes occurs, and the B1 manufacturing method 1 can be implemented.

[0321] As the amount of the reactant, in terms of molar equivalent conversion, the lower limit is preferably 0.80 eq or more, more preferably 0.90 eq or more, and most preferably 0.95 eq or more. The upper limit is preferably 2.00 eq or less, more preferably 1.50 eq or less, and further preferably 1.10 eq or less. This manufacturing method affects the purity of the obtained tin compound (B1) by controlling the selectivity reaction of 1 equivalent through equivalent control. In addition, by controlling the equivalent and reaction conditions, a monoalkyltin composition (precursor mixture) containing RSnX3 (A1), RSnX3, RSnX2Y (B1), RSnXY2, RSnY3, etc. in a specific composition can sometimes be obtained.

[0322] <Reaction conditions of B1 manufacturing method 2>

[0323] As B1 manufacturing method 2, a monoalkyltin compound RSnY3 and a reactant (M1 or M2) containing an amount equivalent to 2 equivalents of X react in an organic solvent (S1) (solvent-free as required) under specific conditions to obtain a tin compound (B1). As the reaction conditions, the content described in "Manufacturing method 1 of tin compound (A1)" can also be referred to. <COUNTER>0000962

[0324] In particular, as the Y group of the raw material tin compound RSnY3, from the viewpoints of the selectivity and reactivity of 2-equivalent addition, an OR' Y group or an NR' Y 2 group is preferably used, and from the viewpoint of reactivity, NR' Y 2 is preferred. On the other hand, from the viewpoints of the combination with the reactant and selectivity, an OR' YFurthermore, as reactants, those with an HX structure can sometimes provide high-purity products without the inclusion of metal, and are therefore preferred, especially those with a highly reactive OR' group in the starting tin compound RSnY3. Y base or NR' Y The 2-element case is effective. Particularly with reactants having an HX structure, secondary and tertiary alcohols (isopropanol, tert-butanol, 4-methyl-2-pentanol, etc.) exhibit high selectivity for 2 equivalents due to steric hindrance, and are therefore preferred. Furthermore, similarly, this reaction sometimes occurs when RSnY3 is stored mixed with a reactant having an HX structure, enabling method 2 for manufacturing B1. The amount of reactant, in molar equivalents, is preferably 1.80 eq or more at the lower limit, more preferably 1.90 eq or more, and most preferably 1.95 eq or more. The upper limit is preferably 4.00 eq or less, more preferably 2.50 eq or less, and even more preferably 2.10 eq or less. This manufacturing method, by controlling the selectivity of 2 equivalents, affects the purity of the obtained tin compound (B1). In addition, by controlling the stoichiometry and reaction conditions, it is sometimes possible to obtain monoalkyltin compositions (precursor mixtures) containing RSnX3(A1), RSnX3, RSnX2Y(B1), RSnXY2, RSnY3, etc., with specific compositions.

[0325] <<Applications as a corrosion-resistant material>>

[0326] The tin hydrolysate (P1) of this embodiment is obtained by hydrolyzing a tin composition prepared by using tin compounds (A1) and (B1) in a specific ratio.

[0327] <Method for manufacturing tin hydrolysate>

[0328] As a method for manufacturing this tin hydrolysate, hydrolysis is preferably carried out by a process having the following steps.

[0329] <Step 1> Use a tin composition made by combining tin compounds (A1) and (B1) in a specific ratio as raw material.

[0330] <Step 2> Contact the above raw materials with water and / or water vapor.

[0331] In step 1 above, a monoalkyltin composition (A1B1) is prepared by mixing tin compounds (A1) and (B1) in a specific ratio. In this step, the precursor mixture does not undergo hydrolysis, and its chemical structure remains unchanged. Therefore, step 1 is preferably carried out under an inert gas atmosphere. Then, the monoalkyltin composition is used in step 2. As a preparation method, two or more precursors can be mixed to prepare the composition. In steps such as synthesis, purification, and storage, the monoalkyltin composition already formulated with (A1) and (B1) can be used. In steps 1 and 2, no other solvents or additives are required, especially when the raw materials (precursors) are uniformly adjusted and mixed (step 1) in liquid form and uniformly reacted with water or water vapor (step 2). In each step, it is preferable to use 100 parts by mass or more of an organic solvent relative to 100 parts by mass of the raw materials.

[0332] Specifically, preferably, a tin composition containing tin compounds (A1) and (B1) in a specific ratio is prepared under an inert gas atmosphere (step 1). This composition, or a complex prepared by combining it with an organic solvent as needed, is then converted into a gaseous and / or liquid state and brought into contact with water and / or water vapor to hydrolyze the precursor (step 2). In this case, the organic solvent used in step 2 is preferably a solvent that does not hydrolyze the precursor; specifically, an aprotic solvent is preferred, and a dehydrated aprotic solvent is even more preferred. The water used in step 2 is preferably liquid water.

[0333] [Organic solvents during hydrolysis]

[0334] In this manufacturing method, there are no particular limitations on the organic solvent, but preferred organic solvents include, for example, hydrocarbon solvents (hexane, cyclohexane, heptane, decane, decahydronaphthalene, etc.), aromatic solvents (benzene, toluene, xylene, anisole, etc.), ether solvents (THF (tetrahydrofuran), diethyl ether, TBME (tert-butyl methyl ether), dibutyl ether, 3-methylTHF, THP (tetrahydropyran), 3-methylTHP, etc.), ketone solvents (acetone, MEK (methyl ethyl ketone), MIBK (methyl isobutyl ketone), etc.), amide solvents (DMF (N,N-dimethylformamide), DMAC (N,N-dimethylacetamide), etc.), esters (ethyl acetate, butyl acetate, etc.), halogen solvents (dichloromethane, chloroform), and alcohol solvents (methanol, ethanol, isopropanol, butanol, 4-methyl-2-pentanol, etc.), preferably combinations of solvents that do not react with the precursor used. Specifically, in highly reactive systems where the precursor structure includes NR2 groups, aprotic solvents are preferred. Aprotic solvents specifically include aromatic, hydrocarbon, ether, and halogen solvents. These solvents can be used alone or in combination of two or more. The solvent is preferably one that does not itself contribute to metal contamination. The solvent used in hydrolysis can sometimes affect the crystallinity of the resulting tin hydrolysate. If a low-polarity aprotic solvent with low solubility for tin hydrolysate (especially hydrocarbon solvents such as hexane) is used, crystallinity may decrease, resulting in a highly soluble tin hydrolysate, which is therefore preferred. Furthermore, when hydrolysis is performed in a coating solvent and a thin film is formed after coating, compatibility with the solvent used in hydrolysis as a coating solvent is sometimes necessary. In such cases, suitable ketone solvents, ester solvents, alcohol solvents, etc., as described above are sometimes preferred as coating solvents in semiconductor processes.

[0335] [Conditions for hydrolysis]

[0336] The temperature during hydrolysis is not particularly limited, provided the reaction with water proceeds and the hydrolysis occurs at a target rate. In the aforementioned process using an organic solvent and liquid water, a temperature between -10°C and 150°C is preferred. The rate of hydrolysis originates from the structure of the hydrolyzable groups X and Y; therefore, the suitable temperature for this hydrolysis depends on the structure of the substituents X and Y. When substituents X and Y are OR', the lower limit of the hydrolysis temperature is preferably 0°C or higher, preferably 30°C or higher, and particularly preferably 40°C or higher. The upper limit is preferably 150°C or lower, and more preferably 140°C or lower. When substituents X and Y are NR'2, the temperature is preferably -10°C or higher, preferably 0°C or higher, and the upper limit is preferably 150°C or lower, and particularly preferably 140°C or lower.

[0337] Furthermore, if no tin hydrolysate is precipitated after hydrolysis using an organic solvent, it is preferable to evaporate the organic solvent to precipitate the tin hydrolysate. The conditions for evaporating the organic solvent can be either heating it under normal pressure or heating it under reduced pressure. Additionally, this process of evaporating the organic solvent is sometimes performed during the formation of the thin film containing the tin hydrolysate, which will be described later.

[0338] <Method for forming thin films containing tin hydrolysate>

[0339] The tin hydrolysate (P1) shown above can be used as a photoresist material. Regarding its use as a photoresist material, the method disclosed in Japanese Patent Application Publication No. 2021-21953 can be used, for example. For its use as a photoresist material, methods for forming a thin film (coating layer, film, etc.) containing the tin hydrolysate on a substrate include, for example, the following dry and wet methods.

[0340] In the dry process, a monoalkyltin compound (precursor) used as a raw material for tin hydrolysate is volatilized under heating and reduced pressure and used as vapor. Water vapor, other gases, etc., react with the vapor of the precursor or the precursor deposited onto the substrate to synthesize the tin hydrolysate. By implementing this method on the substrate, a thin film (coating film) containing the tin hydrolysate can be formed on the substrate. Depending on the needs, the formation of the tin hydrolysate may sometimes be promoted by combining reactions, heating, cleaning, etc., before and after this process.

[0341] In the wet process, a method is as follows: a raw material containing a monoalkyltin compound (precursor) as a raw material for tin hydrolysate is reacted with water or the like in a solution or solid state to perform hydrolysis, thereby obtaining tin hydrolysate. The tin hydrolysate can then be dissolved in an organic solvent or the like and used as a coating solution. Alternatively, sometimes a solution containing the precursor is first coated onto a substrate, and then part or all of the above hydrolysis process is applied to the substrate to generate the tin hydrolysate.

[0342] In the coating process, coating can be applied to the substrate using optional coating or printing techniques, or a thin film (coated film) containing tin hydrolysate can be formed on the substrate.

[0343] <Patterning of Thin Films>

[0344] The films obtained by any of the above methods are sometimes stabilized or partially condensed before light irradiation by drying, heating, etc. Typically, the films (coated films) are thin, for example, having an average thickness of less than 10 micrometers. To pattern very small features, very thin submicron films, such as those less than about 100 nm, then less than 50 nm, and especially less than 30 nm, are sometimes preferred. The resulting films (coated films) are treated by exposure in a manner that makes them resistant to development / etching as part of the composition, and therefore can be called "resist".

[0345] For thin films (coated films), exposing a selected pattern or the negative portion of a pattern to appropriate radiation, such as extreme ultraviolet light, electron beams, or ultraviolet light, can form a latent image with developer-resistant and developer-soluble regions. After exposure to appropriate radiation and before development, reacting the film by heating or other methods can differentiate the latent image from the unirradiated areas. The latent image contacts the developer, forming a physical image, i.e., a patterned film. Further heating of the patterned film can stabilize any remaining patterned film on the surface. The patterned film can be used as a physical mask for further processing according to the pattern, such as etching of the substrate and / or attachment of additional materials. After using the patterned film as a resist as desired, any remaining patterned film can be removed at an appropriate time during processing, but the patterned film can also be assembled into the final structure.

[0346] The conditions for each process are described in more detail below.

[0347] <Preparation and Filtration of Corrosion Resist Solution>

[0348] Typically, the resist solution used in the aforementioned wet process is prepared by thorough mixing using a suitable mixing apparatus appropriate for the volume of the material to be formed. Additionally, appropriate filtration can be used to remove any contaminants or other insoluble components. In some embodiments, the prepared resist solutions are sometimes used in combination. Furthermore, in addition to adding a tin compound as the main component, various additives may be added to the resist solution.

[0349] <Coating on substrate>

[0350] The precursor in the dry process and the resist solution in the wet process are appropriately selected based on their adhesion to the substrate and subsequent processability. The precursor in the dry process and the resist solution in the wet process can typically adhere to the substrate surface. Furthermore, the substrate may comprise two or more layers on its surface. In some embodiments, the substrate surface may be treated to allow the precursor in the dry process and the resist solution in the wet process to adhere. Additionally, the substrate surface may be cleaned and / or smoothed as needed. Suitable substrate surfaces may contain optional, appropriate materials. Several substrates of particular interest (e.g., silicon wafers, silicon dioxide substrates) contain other inorganic materials such as ceramic materials, polymer substrates, such as organic polymers, composites thereof, and combinations thereof on the substrate surface and / or within the substrate surface layers. Thin, circular wafers are convenient as substrates, but structures of optional, appropriate shapes can be used.

[0351] Substrates having polymer layers on polymer substrates or non-polymer structures are sometimes desirable for specific applications due to their low cost and flexibility. The polymer can be selected based on the relatively low processing temperatures that can be used when processing the patterned materials described in this specification. Preferably, the polymer comprises, for example, polycarbonate, polyimide, polyester, polyolefin, copolymers thereof, and mixtures thereof.

[0352] Typically, especially for high-resolution applications, the substrate preferably has a flat surface. However, in certain embodiments, the substrate sometimes has a substantial morphology, and for specific patterning applications, the resist coating is intended to fill or planarize the features. Such functionality of resist materials is described by reference in U.S. Patent Application Publication No. 2015 / 0253667 (Bristol et al.), entitled “Pre-Patterned Hard Mask for Ultrafast Lithographic Imaging”, cited in this specification.

[0353] Typically, to coat the precursor in a dry process and the resist solution in a wet process onto a substrate, an optional and suitable coating process can be used. As coating methods, in the case of a wet process, spin coating, spray coating, dip coating, blade coating, and printing methods (e.g., inkjet printing and screen printing) are preferred; as a dry process, vapor deposition methods such as physical vapor deposition and chemical vapor deposition are preferred. Some of these coating methods form patterns during the coating process, but the resolution obtained by printing, etc., is significantly lower than the resolution obtained by the radiation-based patterning described in this specification. To provide greater control over the coating process, the coating material can be applied in multiple coating steps. For example, performing spin coating twice or more in a wet process and vapor deposition twice or more in a dry process can achieve the desired final coating thickness. The heat treatment described below can be applied after each coating step or after two or more coating steps.

[0354] When using radiation to perform patterning, spin coating may be a preferred method for achieving relatively uniform coverage of the substrate, but edge effects may occur. In some embodiments, the wafer can be rotated at a speed of about 500 rpm to about 10,000 rpm, in further embodiments at a speed of about 1,000 rpm to about 7,500 rpm, and in additional embodiments at a speed of about 2,000 rpm to about 6,000 rpm. The rotation speed can be adjusted in a way that achieves the desired coating thickness.

[0355] Spin coating can be performed in about 5 seconds to about 5 minutes, and in a further embodiment, in about 15 seconds to about 2 minutes. Using an initial low-speed rotation (e.g., 50 to 250 rpm), an initial overall coating of the composition can be performed on the entire substrate. To remove any edge welds, water or other suitable solvents can be used to perform backwashing, edge weld removal steps, etc. Those skilled in the art will understand that additional ranges of spin coating parameters within the aforementioned defined range are included within the scope of this disclosure.

[0356] The thickness of a coated film typically tends to depend on the concentration, viscosity, and spin-coating speed of the resist solution in wet processes, and on the vapor deposition pressure in dry processes. In other coating processes, the thickness can generally be adjusted by selecting coating parameters. In some embodiments, a thin coating is sometimes desirable to facilitate the formation of small and highly customizable features in subsequent patterning processes. For example, the dried coated film may have an average thickness of less than about 10 μm, in other embodiments less than about 1 μm, in further embodiments less than about 250 nm, in additional embodiments from about 1 nm to about 50 nm, in other embodiments from about 2 nm to about 40 nm, and in some embodiments from about 3 nm to about 25 nm. Those skilled in the art will understand that additional ranges of thickness within the aforementioned defined ranges are included within the scope of this disclosure. Thickness can be evaluated using non-contact methods of X-ray reflectance and / or polarization analysis based on the film's optical properties. Generally, a relatively uniform coated film is preferred for ease of processing. In some embodiments, the variation in coating thickness is less than ±50% relative to the average coating thickness, in further embodiments less than ±40%, and in additional embodiments less than approximately ±25% relative to the average coating thickness. In some embodiments, such as coatings with high uniformity on larger substrates, the evaluation of coating uniformity can be performed excluding the 1 cm edge. That is, the uniformity of the coating is not evaluated for portions within 1 cm of the coating edge. Those skilled in the art will understand that additional ranges within the aforementioned defined ranges are included within the scope of this disclosure.

[0357] Two or more coating processes form coating materials with larger surface areas and / or stimulating evaporation of the solution, resulting in the evaporation of some of the solvent. Solvent evaporation tends to increase the viscosity of the coating material as the concentration of the species in the material increases. The goal during the coating process is to remove sufficient solvent or to react the active substances in the dry process precursor and the wet process resist solution to stabilize them for further processing. That is, between the coating step and the subsequent heating step, solvent can be removed, or hydrolysates of tin compounds can be formed, or condensation can occur. Typically, the dry process precursor and the wet process resist solution can be heated before exposure to radiation to promote densification. In the dried coating film, the dry process precursor and the wet process resist solution typically form a high-molecular-weight metal oxo / hydroxyl network based on metal oxo-hydroxyl ligands, where the metal also has a molecular solid composed of several hydrocarbon groups or polynuclear metal oxo / hydroxyl species with hydrocarbon groups.

[0358] In the case of wet processes, the solvent removal process can either quantitatively control a specific amount of solvent remaining in the coating material or not. Empirical evaluation of the properties of the resulting resist solution can usually be carried out in order to select processing conditions that are effective for the patterning process.

[0359] Heating is not required for the success of the process, but it is sometimes desirable to heat the substrate in order to accelerate the process and / or increase the reproducibility of the process.

[0360] In embodiments where heating is applied to remove the solvent, the coated substrate can be heated to about 45°C to about 250°C, and in further embodiments, to about 55°C to about 225°C. Heating for solvent removal is typically performed for at least about 0.1 minutes, in further embodiments for about 0.5 minutes to about 30 minutes, and in additional embodiments for about 0.75 minutes to about 10 minutes. Those skilled in the art will understand that additional ranges of heating temperature and time within the aforementioned defined ranges are included within the scope of this disclosure. The result of the heat treatment and densification is that the coated film can exhibit an increase in refractive index and radiation absorption without significantly sacrificing contrast.

[0361] <Exposed Patterned and Patterned Coating Films>

[0362] The coated film can be finely patterned using radiation. As described above, depending on the composition of the resist solution, the composition of the corresponding coated film can be designed to sufficiently absorb radiation of the desired form. Radiation absorption generates energy that breaks the bonds between the metal and hydrocarbon groups, resulting in at least a portion of the hydrocarbon groups being unusable for material stabilization. Radiation decomposition products containing hydrocarbon groups or fragments may or may not diffuse from the film depending on process variables and the identity of such products. Through sufficient radiation absorption, the exposed coated film condenses, forming an enhanced metal oxo / hydroxyl network, which may contain water absorbed from the surrounding atmosphere. Radiation can typically be delivered according to the selected pattern. This radiation pattern is transferred into the coated film as a latent image with corresponding irradiated and non-irradiated areas. The irradiated areas tend to form a chemical change in the composition of the coated film. As described below, during development, by selectively removing the non-irradiated portions or selectively removing the irradiated portions from the coated film, a pattern with very sharp edges can be formed.

[0363] Radiation can typically be directed toward the substrate through a mask, or the radiation beam can be scanned across the entire substrate in a controlled manner. Typically, the radiation can include electromagnetic radiation, electron beams (beta radiation), or other suitable radiation. Electromagnetic radiation can typically have a desired wavelength or wavelength range, such as visible light, ultraviolet light, or X-rays.

[0364] The resolution achievable for radiation patterns typically depends on the wavelength of the radiation; higher resolution patterns can usually be achieved using shorter wavelength radiation. Therefore, ultraviolet light, X-rays, or electron beams are sometimes preferred, especially for achieving high-resolution patterns.

[0365] According to the international standard ISO 21348 (2007), which is referenced in this specification, ultraviolet light extends across wavelengths greater than 100 nm and less than 400 nm. A krypton fluoride laser can be used as a 248 nm ultraviolet source. The ultraviolet region can be subdivided, within permissible standards, by various methods into extreme ultraviolet (EUV) light greater than 10 nm and less than 121 nm, and far ultraviolet (FUV) light greater than 122 nm and less than 200 nm, etc. A 193 nm line from an argon fluoride laser can be used as the radiation source in FUV. EUV light at 13.5 nm was used for photolithography, generated by a Xe or Sn plasma source excited using a high-energy laser or discharge pulse. Soft X-rays can be defined as greater than 0.1 nm and less than 10 nm.

[0366] The amount of electromagnetic radiation can be characterized by the flux, or dose, obtained by integrating the radiation flux relative to the exposure time. A suitable radiation flux can be approximately 1 mJ / cm². 2 ~ Approximately 150 mJ / cm 2 In a further embodiment, it can be approximately 2 mJ / cm². 2 ~ Approximately 100 mJ / cm 2 Furthermore, in a further embodiment, it can be approximately 3 mJ / cm³. 2 ~ Approximately 50 mJ / cm 2 Those skilled in the art will understand that additional ranges of radiation doses within the aforementioned defined range are included within the scope of this disclosure.

[0367] In electron beam lithography, the electron beam typically induces secondary electrons, which usually cause changes in the irradiated material. Resolution can be considered, at least in part, as a function of the range of secondary electrons within the material. Here, it is assumed that higher resolution is generally achieved by a shorter range of secondary electrons. Based on the high resolution achievable by electron lithography using the inorganic coating materials described in this specification, the range of secondary electrons in the inorganic material is limited.

[0368] Electron beams can be characterized by their energy, which can range from about 5V to about 200kV, and in further embodiments from about 7.5V to about 100kV. A proximity-corrected beam dose at 30kV can be approximately 0.1μC / cm². 2 ~ Approximately 5mC / cm 2The range, in a further embodiment, can be approximately 0.5 μC / cm. 2 ~ Approximately 1 mC / cm 2 The range, and in other embodiments, can be approximately 1 μC / cm. 2 ~ Approximately 100 μC / cm 2 The range is defined in this specification. Those skilled in the art can calculate the corresponding dose at other beam energies based on the teachings in this specification. It should be understood that additional ranges of electron beam characteristics within the aforementioned defined range are included within the scope of this disclosure.

[0369] Based on the design of the precursor in the dry process and the resist solution in the wet process, there is a significant contrast in material properties between the irradiated area and the non-irradiated area with substantially unchanged hydrocarbon groups in the coated film. Although the contrast of dosage can be improved by post-irradiation heat treatment, satisfactory results can be obtained even without post-irradiation heat treatment in some embodiments. It is believed that post-exposure heat treatment, which anneals the irradiated area, will not cause significant shrinkage of the non-irradiated area of ​​the coated film due to thermal breakdown of hydrocarbon-metal bonds, thus preventing increased shrinkage. In embodiments using post-irradiation heat treatment, the post-irradiation heat treatment can be carried out at a temperature of about 45°C to about 250°C, in additional embodiments at a temperature of about 50°C to about 190°C, and in further embodiments at a temperature of about 60°C to about 175°C. Post-exposure heating can typically be carried out for at least about 0.1 minutes, in further embodiments for about 0.5 minutes to about 30 minutes, and in additional embodiments for about 0.75 minutes to about 10 minutes.

[0370] Those skilled in the art will understand that additional ranges of post-irradiation heating temperatures and times within the aforementioned defined ranges are included within the scope of this disclosure. This high contrast in material properties facilitates the formation of sharp lines in the developed patterns described in the following sections. As a result, after exposure to radiation, the coating film is patterned through both irradiated and unirradiated areas.

[0371] <Development and Patterning Structures>

[0372] Image development includes: contacting a coating film containing a latent image with a developer composition to remove unexposed areas to form a negative image; or removing exposed areas to form a positive image. If the precursor in the dry method and the resist solution in the wet method described in this specification are used, effective negative or positive patterning with the desired resolution can generally be performed based on the same coating and using a suitable developer. In particular, there is a tendency for the exposed areas to at least partially condense, increasing the properties of the components constituting the coating film. As a result, the exposed areas are resistant to dissolution in organic solvents, while the unexposed areas remain soluble in organic solvents. The exposed areas further condense due to the cleavage of hydrocarbon-tin bonds, resulting in the release of hydrocarbon groups, and the metal oxide-like properties of the components constituting the coating film tend to increase. On the other hand, the unexposed material is hydrophobic due to the non-release of hydrocarbon groups, making it difficult to dissolve in weak alkaline or acidic aqueous solutions. Therefore, for positive patterning, an alkaline aqueous solution can be used to remove the exposed material while retaining the unexposed material.

[0373] Hydrocarbon-based precursors in dry processes and resist solutions in wet processes generate inherently hydrophobic materials. Irradiation, which breaks at least a portion of the organometallic bonds, transforms the material into a less hydrophobic, i.e., more hydrophilic material. This change in property provides a significant contrast between the irradiated and unirradiated areas of the coating film, thereby enabling both positive and negative patterning of the coating film. Specifically, the irradiated areas of the coating film condense to a certain extent into a composition with more metal oxides, but even without significant heating, the degree of condensation is typically moderate; therefore, the irradiated material is insoluble compared to conventional development using a developer.

[0374] In the case of negative image formation, the developer can be an organic solvent, such as the solvent used to form the resist solution. Typically, the choice of developer is influenced by solubility parameters related to the composition of the coated film (the chemical composition of the irradiated and unirradiated areas), as well as the developer's volatility, flammability, toxicity, viscosity, and potential chemical interactions with other process materials. In particular, suitable developers include, for example, aromatic compounds (e.g., benzene, xylene, toluene), esters (e.g., propylene glycol monomethyl acetate, ethyl acetate, ethyl lactate, n-butyl acetate, butyrolactone), alcohols (e.g., 4-methyl-2-pentanol, 1-butanol, isopropanol, 1-propanol, methanol), ketones (e.g., methyl ethyl ketone, acetone, cyclohexanone, 2-heptanone, 2-octanone), ethers (e.g., tetrahydrofuran, dioxane, anisole), etc. Development can be performed from about 5 seconds to about 30 minutes, in a further embodiment from about 8 seconds to about 15 minutes, and in an additional embodiment from about 10 seconds to about 10 minutes. Those skilled in the art will understand that additional scope within the aforementioned explicit scope is included within the scope of this disclosure.

[0375] In the case of positive image formation, the developer is typically an acidic or alkaline aqueous solution. In some embodiments, alkaline aqueous solutions can be used to obtain sharper images. To reduce contamination from the developer, it is sometimes desirable to use a developer that does not contain metal atoms. Therefore, as a developer, quaternary ammonium hydroxide compositions, such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, or combinations thereof, are preferred. Generally, quaternary ammonium hydroxides of particular interest can be derived from formula R. 4 NOH (where R = methyl, ethyl, propyl, butyl, or a combination thereof) is used. The coating materials described in this specification can generally be developed using the same developers commonly used in polymer resists, specifically tetramethylammonium hydroxide (TMAH). Commercially available TMAH can be used at a concentration of 2.38% by mass, which is suitable for the treatments described in this specification. Alternatively, mixed tetraalkylammonium hydroxides can be used. Typically, the developer may contain about 0.5% by mass to about 30% by mass of tetraalkylammonium hydroxide or the same quaternary ammonium hydroxide; in further embodiments, it may contain about 1% by mass to about 25% by mass of tetraalkylammonium hydroxide or the same quaternary ammonium hydroxide; and in other embodiments, it may contain about 1.25% by mass to about 20% by mass of tetraalkylammonium hydroxide or the same quaternary ammonium hydroxide. Those skilled in the art will understand that additional ranges of developer concentrations within the aforementioned defined ranges are included within the scope of this disclosure.

[0376] In addition to the main developer composition, the developer may contain additional compositions to facilitate the developing process. Suitable additives include, for example, cations selected from the group consisting of ammonium, d-block metal cations (hafnium, zirconium, lanthanum, etc.), f-block metal cations (cerium, lutetium, etc.), p-block metal cations (aluminum, tin, etc.), alkali metals (lithium, sodium, potassium, etc.), and combinations thereof, and anions selected from the group consisting of fluorine, chlorine, bromine, iodine, nitric acid, sulfuric acid, phosphoric acid, silicic acid, boric acid, peroxides, butoxides, formic acid, oxalic acid, ethylenediaminetetraacetic acid (EDTA), tungstic acid, molybdic acid, etc., and combinations thereof. Other potentially useful additives include, for example, molecular chelating agents, such as polyamines, alkanolamines, amino acids, carboxylic acids, or combinations thereof. In the presence of optional additives, the developer may contain about 10% by mass or less of the additive, and in further embodiments, about 5% by mass or less of the additive. Those skilled in the art will understand that additional ranges of additive concentrations within the aforementioned defined ranges are included within the scope of this disclosure. Additives can be selected to improve contrast, sensitivity, and linewidth roughness. Additives in developers can also inhibit the formation and precipitation of metal oxide particles.

[0377] In the case of weaker developers, such as lower concentrations of aqueous developers, diluted organic developers, or compositions (where the coating has a lower development speed), a higher temperature development process can be used to increase the process speed. In the case of stronger developers, the temperature of the development process can be lowered to reduce the development speed and / or control the development kinetics. Typically, the development temperature can be adjusted to an appropriate value consistent with the solvent's volatility. Furthermore, the developer containing the coating film components dissolved near the developer-coating interface can be dispersed by ultrasonic treatment during development.

[0378] The developer can be applied to the coated film containing the latent image using any suitable means. For example, the developer can be sprayed onto the patterned coating material. Alternatively, spin coating can be used. In the case of automated processing, a spin-dip method can be used, which involves statically pouring the developer onto the coating material. Where desired, the development process can be completed using spin rinsing and / or drying. Suitable rinsing solutions include, for example, ultrapure water, methanol, ethanol, propanol, and combinations thereof in the case of negative patterning, and ultrapure water in the case of positive patterning. After the image is developed, the coated film is disposed on the substrate as a patterned coated film.

[0379] After the development step, the patterned coating film may be heat-treated to further condense, dehydrate, densify, or remove residual developer from the material. This heat treatment is particularly preferred for embodiments that introduce oxide coating materials into the final device, but it is sometimes also desirable to perform heat treatment on some embodiments where the coating film is ultimately removed as a resist, in order to further facilitate patterning and stabilize the coating film. In particular, baking the patterned coating film can be performed under conditions where the patterned coating film exhibits a desired level of etch selectivity. In some embodiments, the patterned coating film can be heated to a temperature of about 100°C to about 600°C; in further embodiments, it can be heated to a temperature of about 175°C to about 500°C; and in additional embodiments, it can be heated to a temperature of about 200°C to about 400°C. Heating can be performed for at least about 1 minute, in other embodiments for about 2 minutes to about 1 hour, and in further embodiments for about 2.5 minutes to about 25 minutes. Heating can be performed in air, in a vacuum, or in an atmosphere of inert gas such as Ar or N2. Those skilled in the art will understand that additional ranges of temperature and time for heat treatment within the aforementioned defined range are included within the scope of this disclosure. Similarly, non-thermal treatments, including full-surface UV exposure or exposure to oxidizing plasmas such as O2, can also be used for the same purpose.

[0380] For existing organic photoresists, if the aspect ratio (height divided by width) of the structure becomes very large, the structure is prone to pattern collapse. Pattern collapse may be related to the mechanical instability of high aspect ratio structures, where forces associated with the processing steps, such as surface tension, deform the structural elements. Low aspect ratio structures are more stable regarding potential deformation forces. By using the precursor in the dry process and the photoresist solution in the wet process described in this specification, structures with thinner coating films can be effectively processed, thus achieving improved patterning without the need for high aspect ratio patterned coating films. Therefore, for patterned coating films, very high-resolution features are formed without relying on high aspect ratio features.

[0381] The resulting structure can have sharp edges and very low linewidth roughness. In particular, in addition to reducing linewidth roughness, it also enables the formation of high contrast, small features and the space between features, and the ability to form extremely high-resolution two-dimensional patterns (e.g., sharp corners). Therefore, in some embodiments, adjacent straight portions of adjacent structures can have an average pitch (half-pitch) of about 60 nm (30 nm half-pitch), in some embodiments it can have an average pitch (half-pitch) of about 50 nm (25 nm half-pitch), and in a further embodiment it can have an average pitch (half-pitch) of about 34 nm (17 nm half-pitch).

[0382] The spacing is evaluated by design and can be confirmed by scanning electron microscopy (SEM), for example, by top-view images. In the context of this specification, spacing refers to the spatial period of repeating structural elements, i.e., the distance between centers; as is commonly used in this art, half-spacing is half the spacing. The feature size of the pattern can also represent the average width of features generally evaluated away from corners, etc. Additionally, features can also refer to gaps between material elements and / or material elements themselves. In some embodiments, the average width can be about 25 nm or less, in further embodiments about 20 nm or less, and in additional embodiments about 15 nm or less. The average linewidth roughness can be about 5 nm or less, in some embodiments about 4.5 nm or less, and in further embodiments about 2.5 to about 4 nm. The evaluation of linewidth roughness is performed by deriving a 3σ deviation relative to the average linewidth using analysis of top-view SEM images. The average includes both high-frequency and low-frequency roughness, i.e., short correlation length and long correlation length, respectively. The linewidth roughness of organic resists is mainly characterized by a long correlation length, but the organometallic coating material of this embodiment exhibits a significantly short correlation length. In pattern transfer processes, short, correlated roughness is smoothed between etching processes, enabling the generation of patterns with significantly improved fidelity. Those skilled in the art will understand that additional ranges of spacing, average width, and linewidth roughness within the aforementioned defined ranges are included within the scope of this disclosure.

[0383] Further processing of patterned coated films

[0384] After a patterned coating film is formed on the substrate, the substrate can be further processed to facilitate the formation of the selected device. Furthermore, to complete the structure, further material attachment, etching, and / or patterning can typically be performed.

[0385] The patterned coating film may or may not be removed. In either case, the quality of the patterned coating film is expected to be improved in order to form improved devices (e.g., devices with smaller setup areas).

[0386] Alternatively or additionally, the attachment of further material according to the mask pattern can alter the properties of the underlying structure and / or provide contact with the underlying structure. The further coating material can be selected based on desired material properties. Furthermore, since the density of the patterned inorganic coating material provides high implantation resistance, ions can be selectively implanted into the underlying structure through the openings in the mask. In some embodiments, the further attached material can be a dielectric, semiconductor, conductor, or other suitable material. The further attached material can be attached using suitable means, such as solution-based steps, chemical vapor deposition (CVD), sputtering, physical vapor deposition (PVD), or other suitable means.

[0387] Typically, multiple additional layers can be attached. Additional patterning can be performed in conjunction with the attachment of two or more layers. Where desired, optional additional patterning can be performed using additional amounts of the coating material described in this specification, polymer-based resists, other patterning methods, or combinations thereof.

[0388] As mentioned above, the patterned coating film may or may not be removed.

[0389] The patterned coating film is assembled into the structure without being removed. In the embodiment where the patterned coating film is assembled into the structure, the characteristics of the patterned coating film can be selected in a way that provides not only the desired patterning characteristics but also the characteristics of the material within the structure.

[0390] When it is desired to remove a patterned coating, the patterned coating functions as a resist, as previously intended. The patterned coating serves to pattern subsequently applied material and / or selectively etch the substrate via spaces within the condensed coating material before removal. The condensed coating material can be removed using a suitable etching process. Specifically, to remove the condensed coating material, dry etching can be performed, for example, using BCl3 plasma, Cl2 plasma, HBr plasma, Ar plasma, or plasma based on other suitable process gases. Alternatively or additionally, to remove the patterned coating material, wet etching can be performed, for example, using aqueous solutions of acids or alkalis, HF (water), or buffered HF (water) / NH4F, or oxalic acid, etc.

[0391] This photoresist material can be used for multiple patterning. That is, this process can be applied to processes involving multiple coatings and multiple patterning. Regarding multiple patterning, a significant difference between the inorganic coating material described in this specification and existing organic photoresists is that organic photoresists remain soluble in existing photoresist casting solvents even after heating and baking. The photoresist material described in this specification can be cured by heating and baking, resulting in its insolubility in organic solvents, thus allowing the formation of coating layers, etc., on the photoresist material.

[0392] Example

[0393] The following examples illustrate the present invention in more detail, but the present invention is not limited to these examples as long as it does not depart from its spirit. It should be noted that, unless otherwise specified, "parts" and "%" in the examples refer to a mass standard.

[0394] Unless otherwise specified, the following raw materials shall be used as raw materials.

[0395] [Organic solvents]

[0396] • Dehydrated hexane: n-Hexane (dehydrated) (manufactured by Kanto Chemical Co., Ltd.)

[0397] [Monoalkyltin compounds (precursors)]

[0398] The various tin compounds are sometimes referred to as follows.

[0399] Tin compounds equivalent to RSnX3(A1)

[0400] iPrSn(NMe2)3: Isopropyltris(dimethylamide)tin, 119 Sn-NMR: -64ppm...Compound(1)

[0401] Tin compounds equivalent to RSnX2Y(B1)

[0402] iPrSn(NMe2)2(NMeCH2NMe2), 119 Sn-NMR: -82ppm...Compound(4)

[0403] [Tin compounds as impurities (A2, A3)]

[0404] Tin compound (A2): iPr2Sn(NMe2)2: diisopropyl, 119 Sn-NMR: -18ppm···Compound(2)

[0405] Tin compound (A3): Sn(NMe2)4: tetraamide, 119Sn-NMR: -120ppm...Compound(3)

[0406] Tin compounds other than compounds (1) to (4): other impurities

[0407] <<Preparation and Analysis of Monoalkyltin Compounds (Precursors)>>

[0408] The prepared precursor was prepared in a manner that constitutes the composition of the comparative examples / exemplary embodiments described below. The composition of each functional group, etc., in the obtained precursor is detailed in Tables 1 and 2 below.

[0409] It should be noted that the abbreviations of the substituents in Table 2 are as follows.

[0410] iPr: Isopropyl, Isopropyl, Molecular formula C3H7

[0411] ·OtAm: tert-pentoxygenated

[0412] ·OiPr: Isopropoxy

[0413] ·NMe2: dimethylamino

[0414] ·OMePen: 4-Methyl-2-pentoxy

[0415] [Precursors containing isopropyltris(dimethylamide)tin]

[0416] Precursors L1A to L1E containing monoalkyltin compounds (A1) and / or (B1) were prepared according to the method shown below, and their analytical values ​​are shown in Table 1 below.

[0417] <Examples 1-2>

[0418] (Manufacturing method of precursor L1B)

[0419] Prepare and use a 200L glass reactor (with a jacket for circulating water) that is shielded from light, a cooling condenser with an internal coil, a stirring device (stirring blades: double star type, diameter: 350mm, width: 110mm, made of SUS coated with Teflon (registered trademark)), and a 50L glass dripping device.

[0420] After reducing the pressure in the reaction apparatus to 3 kPa, three nitrogen purging operations were performed. Hexane (36.6 kg, water 21 ppm) and n-butyllithium [41.0 kg, 96.8 mol (3.09 eq), 15% hexane solution (containing the equivalent of 34.9 kg of hexane)] were added, and the mixture was stirred at 150 rpm [blade tip speed (m / s) = 3.14 × 0.35 × 150 / 60 = 2.74 (m / s)] while maintaining the temperature between -5 and 10°C. Dimethylamine (8.69 kg, 193.6 mol, 6.18 eq) was added dropwise over 1 hour. The resulting lithium dimethylamino slurry was stirred at 23–27°C for 1 hour.

[0421] The temperature of the obtained lithium dimethylamino slurry was adjusted to -10°C, and while maintaining the temperature range (internal temperature -10°C to 0°C) of the hexane solution containing isopropyltrichlorotin (8.40 kg, 31.3 mol, 1.00 eq) (4.20 kg based on the amount of hexane), it was added dropwise over 2 hours from a glass dropping apparatus. Then, the dropping apparatus was rinsed with hexane (0.61 kg) while the dropping apparatus was added dropwise.

[0422] After dropwise addition, the temperature was raised to 25°C over 3 hours and stirred for 16 hours. The resulting reaction solution was filtered through a pressure filter to remove the white solid (LiCl), yielding a clear filtrate. The white solid was further washed with dehydrated hexane (7.3 kg × 3), and the filtrates were combined. The resulting reaction solution was concentrated under reduced pressure. The concentrated solution (10.3 kg) was directly packed into a light-shielded glass simple distillation apparatus under a nitrogen atmosphere. The apparatus was introduced into the distillation apparatus under a nitrogen inert gas atmosphere, and simple distillation was carried out under reduced pressure and heating to obtain the corresponding tin compound (1). The monoalkyltin composition obtained by this distillation was used as the precursor L1B.

[0423] (Distillation conditions)

[0424] • Distillation apparatus: A simple glass distillation apparatus wrapped with light-shielding cloth.

[0425] Distillation conditions: Internal temperature: 70–80℃, Pressure reduction: 0.3 kPa

[0426] <Example 1-1>

[0427] Precursor L1A: A monoalkyltin composition obtained by placing the same monoalkyltin composition as precursor L1B into a flask attached to a cooling condenser and subjecting it to reflux heating at 100°C for 18 hours under a nitrogen atmosphere.

[0428] <Examples 1-2>

[0429] Precursor L1B: The monoalkyltin composition described above as "precursor L1B".

[0430] <Comparative Example 1-1>

[0431] Precursor L1C: A monoalkyltin composition obtained by precision distillation purification of the same monoalkyltin composition as precursor L1B in a distillation column with 30 theoretical plates and a reflux ratio of 10. Compound (4), i.e., the tin compound equivalent to RSnX2Y(B1), was not detected.

[0432] <Examples 1-3>

[0433] Precursor L1D: A monoalkyltin composition obtained by mixing precursors L1A and L1C in a mass ratio of 50:50 under a nitrogen atmosphere.

[0434] <Examples 1-4>

[0435] Precursor L1E: A monoalkyl tin composition obtained by mixing precursor L1B and iPr2Sn(NMe2)2 (tin compound (2)) at a mass ratio of 90:10 under a nitrogen atmosphere.

[0436] [Table 1]

[0437] Precursors L2A to L2F containing monoalkyltin compounds (A1) and / or (B1) were prepared according to the method shown below, and their analytical values ​​are shown in Table 2 below.

[0438] <Comparative Example 2-1: Preparation of precursor L2C>

[0439] (Isopropyltris(tert-pentoxy)tin: a precursor containing iPrSn(OtAm)3)

[0440] The apparatus used is a 100mL two-necked flask (protected from light) equipped with a highly sealed magnetic stirrer (stirring: rod-shaped stir bar, 15mm diameter, PTFE material) and a cooling condenser (cooling water at 10°C). After reducing the pressure to 3kPa, nitrogen purging is performed three times. Add hexane (5.0 mL, 10 ppm water) and isopropyltris(dimethylamide)tin (5.0 g, 16.8 mmol, precursor L1B), stirring at 1000 rpm, and adjust the internal temperature to 20°C in a water bath after temperature adjustment. Then, while stirring at 1000 rpm [blade tip speed (m / s) = 3.14 × 0.015 × 1000 / 60 = 0.785 (m / s)], while maintaining a temperature range of 20–30°C, add tert-amyl alcohol (manufactured by MERCK, 15 ppm water) (4.60 g, 52.1 mmol, 3.1 eq) at 22°C. Then, raise the temperature to 50°C. After stirring at ℃ for 3 hours, the resulting reaction solution was filtered for 5 minutes under nitrogen using a glass filter [filter: manufactured by Kiriyama Corporation, using Kiriyama funnel filter paper 5B, 60mm diameter, the entire filter was shielded from light] to obtain a clear filtrate. The resulting reaction solution was stirred under light-shielding conditions while simultaneously undergoing solvent concentration under reduced pressure (10hPa, 40℃) until no further distillation was confirmed, yielding a concentrated solution of a synthetic tin compound containing isopropyltris(tert-pentoxy)tin. The concentrated solution was then filled into a light-shielding glass container (brown glass container) under a nitrogen atmosphere. The obtained isopropyltris(tert-pentoxy)tin was identified by NMR, and its utilization... 119 The purity determined by Sn-NMR was 99.3 mol%, and no compound equivalent to RSnX2Y(B1) was detected. It was used as the precursor L2C.

[0441] [NMR analysis results of iPrSn(OtAm)3]

[0442] · 119 Sn-NMR (223.8MHz; C6D6): δ-218ppm.

[0443] · 1 H-NMR (400MHz; C6D6): δ1.5-1,6(m,7H,(iPr:1H,tAm3:6H)),1.28(s,18H,tAm3),1.22(d,6H,iPr),0.94(t,9H,tAm3).

[0444] <Example 2-1: Preparation of precursor L2A>

[0445] (Precursors containing iPrSn(NMe2)2(OiPr))

[0446] A 30 mL two-necked flask (protected from light) equipped with a highly sealed magnetic stirrer (stirring: rod-shaped stir bar, 10 mm diameter, PTFE material) and a cooling condenser (cooling water at 10°C) was used. After reducing the pressure to 3 kPa, three nitrogen purging operations were performed. Hexane (1.5 mL, 10 ppm water) and isopropyltris(dimethylamide)tin (1.75 g, 5.96 mmol, precursor L1B) were added, and the mixture was stirred at 1000 rpm and adjusted to 0°C. Then, while stirring at 1000 rpm and maintaining the temperature range of 0–10°C, isopropanol (manufactured by Kanto Chemical Co., Ltd., dehydrated grade) (17.9 mg, 0.30 mmol, 0.05 eq) at 22°C was added. After stirring at 0°C for 1 h, the desired product was obtained. The obtained reaction solution was filtered for 5 minutes under nitrogen using a glass filter [filter: manufactured by Kiriyama Corporation, Kiriyama funnel filter paper 5B, 60mm diameter, the entire filter was shielded from light] to obtain a clear filtrate. The obtained reaction solution was stirred under light-shielding conditions while solvent concentration was carried out under reduced pressure (10hPa, 40°C) until no further distillation was confirmed, yielding a tin composition containing isopropylbis(dimethylamino)(isopropoxy)tin (iPrSn(NMe2)2(OiPr)).

[0447] The obtained tin composition was filled into a light-shielding glass container (brown glass container) under a nitrogen atmosphere. The obtained tin composition was identified by NMR, and its utilization... 119 The Sn-NMR results showed that, as a monoalkyltin compound, a precursor containing 5 mol% (iPrSn(NMe2)2(OiPr)) and 93 mol% (iPrSn(NMe2)3) was obtained. This precursor was used as L2A.

[0448] [NMR analysis results of iPrSn(NMe2)2(OiPr)]

[0449] · 119 Sn-NMR (223.8MHz; C6D6): δ-105ppm

[0450] · 1 H-NMR (400MHz; C6D6): δ4.1(m,1HOiPr), 2.7(s,12HNMe2), 1.6(m,1HiPr), 1.2(m,12H(OiPr:6HiPr:6H)).

[0451] <Example 2-2: Preparation of precursor L2B>

[0452] (Precursors containing iPrSn(OtAm)2(NMe2))

[0453] A highly sealed magnetic stirrer (stirring: 10 mm diameter, PTFE) and a cooling condenser (cooling water at 10°C) were used in a 30 mL two-necked flask (protected from light). The pressure was reduced to 3 kPa, and nitrogen purging was performed three times. Hexane (1.5 mL, 10 ppm water) and isopropyltris(dimethylamide)tin (1.75 g, 5.96 mmol, precursor L1B) were added, and the mixture was stirred at 1000 rpm and adjusted to 0°C. Then, while stirring at 1000 rpm and maintaining the temperature range of 0–10°C, tert-amyl alcohol (manufactured by Merck, 15 ppm water) (1.05 g, 11.9 mmol, 2.0 eq) at 22°C was added. Then, after heating to 20°C and stirring for 1 hour, the resulting reaction solution was filtered for 5 minutes under nitrogen using a glass filter [filter: manufactured by Kiriyama Corporation, using Kiriyama funnel filter paper 5B, 60mm diameter, the entire filter was shielded from light], yielding a clear filtrate. The resulting reaction solution was stirred under light-shielding conditions while simultaneously undergoing solvent concentration under reduced pressure (10 hPa, 40°C) until no further distillation was confirmed, yielding a tin composition containing isopropylbis(tert-pentoxy)(dimethylamino)tin (iPrSn(OtAm)2(NMe2)). The obtained composition was filled into a light-shielding glass container (brown glass container) under a nitrogen atmosphere. The obtained tin composition was identified by NMR, and its utilization... 119 The results of Sn-NMR analysis showed that, as a monoalkyltin compound, a precursor containing 77 mol% iPrSn(OtAm)2(NMe2), 12 mol% iPrSn(OtAm)3, and 9 mol% iPrSn(OtAm)(NMe2)2 was obtained. This precursor was used as L2B.

[0454] [NMR analysis results of iPrSn(OtAm)2(NMe2)]

[0455] · 119 Sn-NMR (223.8MHz; C6D6): δ-165ppm

[0456] · 1 H-NMR (400MHz; C6D6): δ2.7(s,6HNMe2),1.4-1,6(m,5H(iPr:1H,tAm2:4H)),1.3(d,6H,iPr),1.2(s,12HtAm2)),0.9(t,6HtAm2))

[0457] NMR analysis results of iPrSn(OtAm)(NMe2)2

[0458] · 119Sn-NMR (223.8MHz; C6D6): δ-111ppm

[0459] · 1 H-NMR (400MHz; C6D6): δ2.7(s,12HNMe2),1.4-1,6(m,3H(iPr:1H,tAm:2H)),1.3(d,6H,iPr),1.2(s,6HtAm)),0.9(t,3HtAm))

[0460] <Examples 2-3: Preparation of L2D precursor>

[0461] (Contains a precursor of isopropylbis(tert-pentoxy)(4-methyl-2-pentoxy)tin:iPrSn(OtAm)2(OMePen))

[0462] The apparatus used is a 30mL two-necked flask (protected from light) equipped with a highly sealed magnetic stirrer (stirring: 10mm diameter rod stir bar, PTFE material) and a cooling condenser (cooling water at 10°C). After reducing the pressure to 3kPa, nitrogen purging is performed three times. Add hexane (1.5 mL, 10 ppm water) and isopropyltris(dimethylamide)tin (1.75 g, 5.96 mmol, precursor L1B), stirring at 1000 rpm and adjusting to 0°C. Then, while stirring at 1000 rpm and maintaining the temperature range of 0–10°C, add tert-amyl alcohol (manufactured by MERCK, 15 ppm water) (1.05 g, 11.9 mmol, 2.0 eq) at 22°C. Then, after stirring at 20°C for 1 h, while maintaining the temperature range of 20–25°C, add 4-methyl-2-pentanol (manufactured by TCI, called "MePenOH") (0.61 g, 5.96 mmol, 1 ppm water). 0 eq), then, after heating to 50°C and stirring for 2 h, the resulting reaction solution was filtered for 5 minutes under nitrogen using a glass filter [filter: manufactured by Kiriyama Corporation, Kiriyama funnel filter paper 5B, 60 mm diameter, the entire filter was shielded from light], to obtain a clear filtrate. The resulting reaction solution was stirred under light-shielding conditions, and solvent was concentrated under reduced pressure (10 hPa, 40°C) until no further distillation was confirmed, yielding a concentrated solution of a synthetic tin compound containing isopropyltris(tert-pentoxy)tin. The obtained concentrated solution was filled into a light-shielding glass container (brown glass container) under a nitrogen atmosphere. The resulting tin composition was identified by NMR, and its utilization 119 The results of Sn-NMR analysis showed that, as a monoalkyltin compound, isopropylbis(tert-pentoxy)(4-methyl-2-pentoxy)tin accounted for 71 mol%, and iPrSn(OtAm)3 accounted for 18 mol%. It was used as the precursor L2D.

[0463] [NMR analysis results of iPrSn(OtAm)2(OMePen)]

[0464] · 119 Sn-NMR (223.8MHz; C6D6): δ-215ppm

[0465] · 1 H-NMR (400MHz; C6D6): δ4.1(Br,1H),1.7(m,2HMePen)1.5-1,6(m,6H(iPr:1H,tAm2:4H,MePe n:1H)),1.3(d,6H,iPr),1.2(m,15H(3H:MePen12H:tAm2)),0.9(m,12H(6H:MePen6H:tAm2))

[0466] <Examples 2-4: Preparation of precursor L2E>

[0467] Precursors L2C and L2B were mixed in a liquid state at a mass ratio of 90:10 under a nitrogen atmosphere to obtain precursor L2E.

[0468] <Examples 2-5: Preparation of precursor L2F>

[0469] Precursors L2C and L2D were mixed in a liquid state at a mass ratio of 90:10 under a nitrogen atmosphere to obtain precursor L2F.

[0470] [Table 2]

[0471] <<Preparation and Analysis of Tin Hydrolysates Based on Hydrolysis>>

[0472] <Example 3-1: Tin Hydrolysate H1A>

[0473] Under an inert gas atmosphere and in the absence of light, using an airtight syringe, 1.0 g (3.4 mmol, calculated as iPrSn(NMe2)3) of the precursor L1A was added to 10 mL of dehydrated hexane. The resulting liquid was cooled in an ice bath, and while stirring at 200 rpm, 1.0 mL of deionized water (18.2 MΩ) was added over 3 minutes at a time while maintaining a temperature of 0–10 °C. As a result, a slurry of white solid was formed. This slurry was further stirred for 10 minutes while maintaining a temperature of 0–10 °C. The slurry was then filtered through filter paper (Kiriyama funnel filter paper 5B) to obtain a white solid. The solid was washed twice with 3.0 mL of deionized water (18.2 MΩ) and collected in a 20 mL glass bottle. The glass bottle was vacuum dried at 40 °C for 8 h to obtain the white solid tin hydrolysate H1A.

[0474] The composition and crystallinity of the obtained tin hydrolysate were analyzed using the following apparatus and conditions. 119 The sum of the peak integrals of 5-coordinate Sn (-250ppm to -350ppm) in Sn-NMR is set as k1, and the sum of the peak integrals of 6-coordinate Sn (-450ppm to -600ppm) is set as k2. 119 The sum of all peak integrals (including k1 and k2) in the range of 1000ppm to -1000ppm detected by Sn-NMR is set as k3, and the ratio [(k1+k2) / (k3)] relative to k3 is calculated.

[0475] [Analytical Apparatus and Methods]

[0476] • NMR analysis apparatus: Bruker, Avance Neo, 600MHz; probe: Cryo 5mm BBO

[0477] • ESI-MS analyzer: Waters Corporation, Xevo G2-XS Qtof, Measurement mode: ESI positive ion mode, Solvent: Acetonitrile

[0478] • XRD analysis apparatus: PANalytical, X'Pert Pro MPD; X-ray source: CuKα condenser optical system; scanning range: 3–50°; half-width at half-maximum (HWHM) analysis: peaks within the scanning range were separated using contour fitting (Pearson-VII function, pseudo-Voigt function), and the HWHM of each peak was calculated. The diffraction angle 2θ (°) of the peak with the highest intensity within the scanning range and its HWHM are recorded. Additionally, the number of peaks within the diffraction angle 2θ (°) range of 5.00°–15.00° is also recorded.

[0479] <Examples 3-1 to Examples 3-4, Comparative Example 3-1>

[0480] In Example 3-1, the precursors were changed to precursors L1B to L1E as shown in Table 3 below. All other operations were performed the same as in Example 3-1 (the amount of precursor was uniformly 1.0 g, and the same amounts of reagents were used). This yielded tin hydrolysates H1B to H1E as shown below. The composition and crystallinity of the obtained tin hydrolysates were analyzed, and the results are shown in Table 3 below. Additionally, the XRD analysis results of tin hydrolysate H1A from Example 3-1 are also presented. Figure 1 The XRD pattern of H1A is shown below, along with the XRD analysis results of the hydrolysate H1C from Comparative Example 3-1. Figure 2 The image shows the XRD pattern of H1C.

[0481] [Table 3]

[0482] [Analytical results of tin hydrolysate H1A]

[0483] (R = isopropyl chemical formula C3H7)

[0484] Tin hydrolysate H1A 119 The results of the Sn-NMR measurements are shown in Table 3. Peaks with a 1:1 ratio were observed in SnNMR (MeOD): 5-coordinate (RSnO4): -337 ppm and 6-coordinate (RSnO5): -513 ppm. This corresponds to the tin dodecomer cluster (nBuSn) reported in Organometallics 19, 2000, 1940-1949. 12 O 14 The NMR results for (OH)6 are correlated. That is, an NMR result equivalent to the composition RSnO was obtained. (3 / 2-x / 2) (OH) x The compound. Furthermore, apart from k1 and k2, the corresponding peaks did not exist at detectable intensities, therefore the value of (k1+k2) / (k3), indicating purity, was 0.99 or higher. Additionally, as for the analytical results of tin hydrolysate H1A, Figure 3A The middle shows 119 Wide-range Sn-NMR spectrum Figure 3B The middle shows 119 Detailed Sn-NMR spectrum Figure 3C The middle shows 1 Detailed H-NMR spectrum.

[0485] The analytical results of H1A, a tin hydrolysate, obtained by electrospray ionization mass spectrometry (ESI-MS) analysis. Figure 3D The ESI-MS spectrum of H1A is shown below. In this spectrum, a structure corresponding to RSnO is observed. (3 / 2-x / 2) The divalent ion (specifically, chemical formula [(C3H7Sn)). 12 O 14 (OH)6] +2 Peaks corresponding to calculated m / z = approximately 1134, monovalent ions (m / z = approximately 2268), and their potassium adducts (equivalent to m / z + 40).

[0486] [Analytical results of tin hydrolysates H1B~H1E]

[0487] Regarding tin hydrolysates H1B–H1D, the same results as for tin hydrolysate H1A were obtained for NMR and ESI-mass measurements, and the same results were obtained for chemical formula and purity. For tin hydrolysate H1E, impurities equivalent to R2SnO2 (the structure of a hydrolyzed dialkyl impurity) were observed in the Sn-NMR range of -200 to -240 ppm.

[0488] <Examples 4-1 to 4-5, Comparative Example 4-1>

[0489] The precursors were changed to L2A to L2F, and tin hydrolysates H2A to H2F were obtained using the method described below. The obtained tin hydrolysates were then analyzed. The results are shown in Table 4.

[0490] <Example 4-1>

[0491] Under an inert gas atmosphere and in the absence of light, using an airtight syringe, 1.0 g (3.4 mmol, calculated as iPrSn(NMe2)3) of the precursor L2A was added to 10 mL of dehydrated hexane. The resulting liquid was cooled in an ice bath, and while stirring at 200 rpm, 1.0 mL of deionized water (18.2 MΩ) was added over 3 minutes at a time while maintaining a temperature of 0–10 °C. As a result, a slurry of white solid was formed. This slurry was further stirred for 10 minutes while maintaining a temperature of 0–10 °C. The slurry was then filtered through filter paper (Kiriyama funnel filter paper 5B) to obtain a white solid. The solid was washed twice with 3.0 mL of deionized water (18.2 MΩ) and collected in a 20 mL glass bottle. The glass bottle was vacuum dried at 40 °C for 8 h to obtain a white solid tin hydrolysate H2A.

[0492] <Example 4-2>

[0493] Under an inert gas atmosphere and in the absence of light, using an airtight syringe, 2.0 g (4.7 mmol, calculated as iPrSn(OtAm)3) of the precursor L2B was added to 20 mL of dehydrated hexane. The resulting liquid was cooled in an ice bath, and while stirring at 200 rpm, 2.0 mL of dehydrated water (18.2 MΩ) was added over 3 minutes while maintaining a temperature of 0–10 °C. The mixture was further stirred for 10 minutes while maintaining a temperature of 0–10 °C, then heated to 50 °C over 1 hour and stirred at 50 °C for 1 hour. The resulting mixture was then evaporated at 100 rpm in an evaporator while the pressure was reduced to 3 kPa in a 50 °C bath to remove the solvent, yielding a white solid. The solid was dispersed in 20 mL of hexane to obtain a slurry, which was then filtered through filter paper (Kiriyama funnel filter paper 5B) to obtain a white solid. The solid was washed twice with deionized water (18.2 MΩ) (3.0 mL) and collected in a 20 mL glass bottle. The glass bottle was dried under vacuum at 40 °C for 8 h to obtain a white solid tin hydrolysate H2B.

[0494] <Comparative Example 4-1>

[0495] The precursor was changed to L2C, and a white solid tin hydrolysate H2C was obtained by the same method as in Example 4-2.

[0496] <Examples 4-3 to Examples 4-5>

[0497] The precursors were changed to L2D-F, and white solid tin hydrolysates H2D-F were obtained by the same method as in Example 4-2.

[0498] [Table 4]

[0499] [Analytical results of tin hydrolysates H2A-H2F]

[0500] (R = isopropyl chemical formula C3H7)

[0501] Tin hydrolysates H2A~H2F 119 The results of the Sn-NMR measurements are shown in Table 4 above. Peaks with a 1:1 ratio were observed in SnNMR (MeOD): 5-coordinate (RSnO4): -337 ppm and 6-coordinate (RSnO5): -513 ppm. Furthermore, except for k1 and k2, the corresponding peaks did not exist at detectable intensities; therefore, the value of (k1+k2) / (k3), indicating purity, was 0.99 or higher. That is, regarding tin hydrolysates H2A to H2F, although precursors with various hydrolyzable groups X and Y were used as raw materials, the chemical formulas and purity were obtained equivalent to those of tin hydrolysate H1A.

[0502] <<Solubility, Filterability, and Storage Stability of Corrosion Resist Solutions>>

[0503] Using the obtained tin hydrolysate, a resist-based solvent solution (resist solution) was prepared by the following method. The obtained resist solution was subjected to dissolution tests, filtration tests, and storage stability tests, and evaluated according to the following evaluation criteria.

[0504] <Examples 5-1 to 5-4, Comparative Example 5-1>

[0505] Specifically, 0.100 g of each tin hydrolysate (H1A-H1E) and 4-methyl-2-pentanol (4.90 g) used in Examples 3-1 to 3-4 and Comparative Example 3-1 were weighed into 20 mL transparent glass bottles to prepare a resist solution. The bottle containing the resist solution was placed in an ultrasonic generator containing water at room temperature (23°C) and ultrasonic waves were applied for 5 minutes to perform the dissolution operation.

[0506] [Methods for evaluating solubility]

[0507] The solubility of tin hydrolysates is evaluated by comparing the turbidity (transparency) when the tin hydrolysates are dissolved in a resist solvent at a certain concentration. As a specific method, 5.0 g of a mixture containing 2.0% tin hydrolysates in 4-methyl-2-pentanol, as disclosed in Japanese Patent Application Publication No. 2019-500490, was prepared. The turbidity (transparency) of this liquid was compared with that of a standard turbidity solution, and the solubility of the corresponding tin hydrolysates was evaluated by visual inspection. As the standard turbidity solution, kaolin turbidity standard solutions (0 degrees (clear), 50 degrees, 100 degrees, 500 degrees, and 1000 degrees (white turbidity)) as shown in JIS K0110 were used, and the turbidity close to that of the standard turbidity solution was evaluated according to evaluation criteria 1 to 5 below.

[0508] (Evaluation Criteria)

[0509] • Turbidity rating 1: 0 degrees (transparent)

[0510] Turbidity rating 2: 50 degrees

[0511] Turbidity rating 3: 100 degrees

[0512] Turbidity rating 4: 500 degrees

[0513] • Turbidity rating 5: 1000 degrees (cloudy)

[0514] [Filtering Evaluation Methods]

[0515] The filterability of tin hydrolysate is evaluated by comparing the degree of filter clogging using the liquid obtained by dissolving tin hydrolysate in a resist solvent at a certain concentration.

[0516] As a specific method, 5.0 g of a mixture containing 2.0% tin hydrolysate in 4-methyl-2-pentanol, as disclosed in Japanese Patent Application Publication No. 2019-500490, was prepared, and the degree of clogging when filtering the liquid was evaluated according to the following evaluation criteria.

[0517] As a specific procedure, 5.0 g of the mixture was heated to a filter with a pore size of 0.2 μm (approximately 300 kPa) using a 10 mL syringe, and the mixture was then filtered, and the results were evaluated accordingly.

[0518] (Filter used: 0.2μm, PTFE, effective filtration area 4.0cm²) 2 Advantec manufactures disposable membrane filter units (DISMIC 25HP045AN).

[0519] (Evaluation Criteria)

[0520] • Set the setting to "1" for filtering 5.0g without clogging.

[0521] • Set the condition that can filter particles larger than 2.0g without causing clogging to be set to "2".

[0522] • Set to "3" for blockages below 2.0g.

[0523] [Methods for evaluating storage stability]

[0524] In the method for testing filtration, the resist solution, after being filtered, is introduced into a brown glass bottle (20 mL) in the atmosphere, and the bottle cap is closed. Under these conditions, it is stored at 20°C and protected from light for one month. After this storage period, the resist solution is transferred to a transparent bottle and evaluated using the same method as for solubility evaluation; the results are used as an assessment of storage stability.

[0525] [Table 5]

[0526] That is, as can be seen from Tables 3 and 5, the tin hydrolysates shown in Examples 5-1 to 5-4 obtained by using a precursor containing an appropriate amount of RSnX2Y(B1) as raw material have high purity, low crystallinity, high solubility, and high storage stability.

[0527] <Examples 6-1 to 6-5, Comparative Example 6-1>

[0528] Using the same method as in Example 5-1, 5.0 g of a mixture containing 2.0% tin hydrolysates H2A to H2F in 4-methyl-2-pentanol was prepared. The resulting mixture was then evaluated for solubility, filterability, and storage stability in the same manner as in Example 5-1. The results are shown in Table 6.

[0529] [Table 6]

[0530] That is, as can be seen from Tables 4 and 6, the tin hydrolysates shown in Examples 6-1 to 6-5 obtained by using a precursor containing an appropriate amount of RSnX2Y(B1) as raw material have high purity, high solubility, and high storage stability.

[0531] <<The Production of Patterned Thin Films>>

[0532] <Example 7>

[0533] The tin hydrolysate H1A obtained in Example 3-1 was dissolved in 4-methyl-2-pentanol (5 mL) with ultrasound at a concentration of 2.0%. The resulting solution was filtered through a 0.2 μm injection filter to obtain a resist solution containing transparent tin hydrolysate.

[0534] Ozone treatment was performed on silicon wafers (Si substrate, 100 mm diameter) with oxide surfaces for use as substrates for attaching photoresist films. The surface of the Si substrate was treated with hexamethyldisilazane (HMDS) vapor before photoresist attachment. The photoresist solution was spin-coated onto the substrate at 2000 rpm and baked at 90°C for 2 minutes on a heated plate. The film thickness after coating and baking was measured to be approximately 22 nm using an ellipsometry. Ultraviolet light was used (light source: xenon excimer lamp (172 nm, 7.2 eV), manufactured by Ushio Electric Corporation, light source intensity: 0.7 mW / cm²). 2 The coated substrate is exposed to a pattern, which projects the pattern onto the substrate. Then, the substrate is immersed in 2-heptanone for 15 seconds and rinsed for another 15 seconds with the same developer to remove the negative image, i.e., the unexposed parts of the thin film, forming an image with only the exposed parts of the pattern remaining.

[0535] The resulting patterned thin film has high sensitivity and low LWR (roughness), making it an excellent resist material.

[0536] The above embodiments illustrate specific aspects of the present invention, but these embodiments are merely illustrative and not intended to be limiting. Various modifications that will be apparent to those skilled in the art are also within the scope of the present invention.

Claims

1. A tin compound having tin atoms, an organic group R, and oxygen ligands and / or hydroxyl ligands, wherein, The diffraction angle 2θ (°) of the peak with the highest intensity in X-ray diffraction measurements exists in the range of 5.00° to 15.00°. The full width at half maximum (FWHM) of the maximum intensity peak is 1.00°–4.00°. The organic group R has 1 to 30 carbon atoms.

2. The tin compound according to claim 1, wherein, The tin compound is composed of the formula RSnO (3 / 2-X / 2) (OH) X This means that, in the formula, 0 ≤ x ≤ 3.

3. The tin compound according to claim 1, wherein, The tin compound contains the chemical formula (RSn). 12 O 14 (OH)6 +2 Compounds that represent cations.

4. The tin compound according to any one of claims 1 to 3, wherein, 119 The sum of the peak integrals (k1) of 5-coordinate Sn (-250ppm to -350ppm) and the sum of the peak integrals (k2) of 6-coordinate Sn (-450ppm to -600ppm) in Sn-NMR, relative to the sum of the peak integrals (k1+k2) of 6-coordinate Sn (-450ppm to -600ppm), is given by... 119 The ratio of the sum of all peak integral values ​​(including k1 and k2) in the range of 1000ppm to -1000ppm detected by Sn-NMR to (k3) [(k1+k2) / (k3)] is greater than 0.

9.

5. The tin compound according to any one of claims 1 to 4, wherein, 119 The ratio (k1 / k2) of the total integrated peak value (k1) of 5-coordinate Sn (-250ppm to -350ppm) to the total integrated peak value (k2) of 6-coordinate Sn (-450ppm to -600ppm) in Sn-NMR is 0.5 to 2.

5.

6. The tin compound according to any one of claims 1 to 5, wherein, The full width at half maximum (FWHM) of the maximum intensity peak is 1.43° to 4.00°.

7. The tin compound according to any one of claims 1 to 6, wherein, The organic group R has 3 to 10 carbon atoms.

8. The tin compound according to any one of claims 1 to 7, wherein, The organic group R is a hydrocarbon group.

9. The tin compound according to any one of claims 1 to 7, wherein, The organic group R is a hydrocarbon group, and more than 50 mol% of the substituents constituting the hydrocarbon group are secondary hydrocarbon groups R. 2 .

10. A resist solution comprising the tin compound of any one of claims 1 to 9 and an organic solvent.

11. A method for forming a pattern, comprising: The process of coating the resist solution of claim 10 onto the substrate; The process of exposing the object using radiation; And the process of developing using a developer.

12. A thin film on a substrate comprising any one of claims 1 to 9.

13. A patterned thin film on a substrate, comprising any one of claims 1 to 9.

14. A method for manufacturing a substrate, comprising the pattern forming method of claim 11.

15. A monoalkyltin compound, represented by RSnX2Y(B1), In the general formula (B1), R is an organic group having 1 to 30 carbon atoms; X and Y are hydrolyzable groups with different chemical formulas, wherein X is selected from OR', NR'2, and C≡CR', and Y is selected from OR' Y NR' Y 2. C≡CR' Y The R' and R' Y It is an organic group having 1 to 10 carbon atoms; wherein X is NR'2 and / or Y is NR' Y In case 2, R', R' Y They can be the same or different independently; in addition, R' and R' in the molecule Y In the case of two or more, their structures can be different, or they can bond together to form a ring structure.

16. The monoalkyltin compound according to claim 15, wherein, The hydrolyzable groups X and Y are NR'2 and NR', respectively. Y 2, the substituent NR'2 of X and the substituent NR' of Y Y 2 are different chemical formulas.

17. The monoalkyltin compound according to claim 15 or 16, wherein, The hydrolyzable groups X and Y are OR' and OR', respectively. Y The substituent OR' of X and the substituent OR' of Y Y These are different chemical formulas.

18. The monoalkyltin compound according to any one of claims 15 to 17, wherein, The hydrolyzable group X is a substituent NR'2, and the hydrolyzable group Y is a substituent OR'. Y .

19. The monoalkyltin compound according to any one of claims 15 to 18, wherein, The hydrolyzable group X is a substituent OR', and the hydrolyzable group Y is a substituent NR'. Y 2.

20. A monoalkyltin composition comprising 50 mol% to 99.99 mol% of a monoalkyltin compound RSnX3 (A1) and 0.01 mol% or more and less than 50 mol% of RSnX2Y (B1), In the general formulas (A1) and (B1), R is an organic group having 1 to 30 carbon atoms; X and Y are hydrolyzable groups with different chemical formulas, wherein X is selected from OR', NR'2, and C≡CR', and Y is selected from OR' Y NR' Y 2. C≡CR' Y The R' and R' Y An organic group having 1 to 10 carbon atoms; when X is NR'2 and / or Y is NR'2, R', R' Y They can be the same or different independently; in addition, R' and R' in the molecule Y In the case of two or more, their structures can be different, or they can bond together to form a ring structure.

21. A monoalkyltin composition comprising 0.01 mol% or more and less than 50 mol% of a monoalkyltin compound RSnX3 (A1) and 50 mol% to 99.99 mol% or less of RSnX2Y (B1), In the general formulas (A1) and (B1), R is an organic group having 1 to 30 carbon atoms; X and Y are hydrolyzable groups with different chemical formulas, wherein X is selected from OR', NR'2, and C≡CR', and Y is selected from OR' Y NR' Y 2. C≡CR' Y The R' and R' Y An organic group having 1 to 10 carbon atoms; when X is NR'2 and / or Y is NR'2, R', R' Y They can be the same or different independently; in addition, R' and R' in the molecule Y In the case of two or more, their structures can be different, or they can bond together to form a ring structure.

22. The monoalkyltin composition according to claim 20 or 21, comprising the RSnX3(A1), the RSnX2Y(B1), and other monoalkyltin compounds thereof, wherein the sum of the contents of the RSnX3(A1) and the RSnX2Y(B1) is 80 mol% or more.

23. A method for manufacturing a tin compound, comprising manufacturing a tin compound having tin atoms, an organic group R, and oxygen ligands and / or hydroxyl ligands, wherein the tin compound has a diffraction angle 2θ (°) of the maximum intensity peak in X-ray diffraction measurements between 5.00° and 15.00°, a half-width at half-maximum (FWHM) of the maximum intensity peak between 1.00° and 4.00°, and the organic group R has 1 to 30 carbon atoms, wherein... The manufacturing method includes the following steps 1 and 2: <Step 1> uses the monoalkyltin composition according to claim 20 or 21 as raw material; <Step 2> Contact the raw material with water and / or water vapor.

24. The method for manufacturing a tin compound according to claim 23, wherein, In step 2, the raw material is brought into contact with liquid water in a complex of organic solvent.

25. The method for producing a tin compound according to claim 23 or 24, wherein, Step 2 includes a step of preparing a composition by combining 100 parts by mass of the raw material with 100 parts by mass or more of an organic solvent.

26. The method for producing a tin compound according to any one of claims 23 to 25, wherein, The full width at half maximum (FWHM) of the maximum intensity peak is 1.43° to 4.00°.

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