Direct synthesis of organotin alkoxides

Abstract

Synthesis techniques for forming organotin trialkoxide compounds by direct alkylation of tin alkoxides are described. A first method involves reacting an alkali metal tin trialkoxide with an organohalide compound (RXn, where X is a halogen atom, and n > = 1) to form a monoorganotin trialkoxide represented by the formula R [Sn (OR ') 3] n. The method can be used to form a multi-tin trialkoxide compound having a plurality of radiation-sensitive C-Sn bonds. R and R'comprise organic groups and may optionally comprise heteroatoms and / or unsaturated bonds. A second method involves an ultraviolet light driven reaction of a ditin tetraalkoxide with an organic halide compound (RX) to form a monoorganotrialkoxide represented by the formula RSn (OR ') 3. A third method involves visible or ultraviolet driven reaction of a ditin tetraalkoxide or an alkali metal tin trialkoxide with a fluorinated organohalide compound (RFX) to form a fluorinated monoorganotrialkoxide represented by the formula RFSn (OR ') 3. The disclosed methods provide high single organic group specificity. A corresponding organotin trialkoxide composition is also described. The composition is useful in radiation patterning, in particular in radiation patterning using EUV radiation. The organotin trialkoxide composition may be formed on a substrate as a coating capable of radiation patterning.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to co-pending U.S. Provisional Patent Application 63 / 429,261, filed on December 1, 2022, entitled "Selective Synthesis of Organotin Oxides", which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present invention relates to a general synthetic method for forming organotin trialkoxide compounds, which involves the direct alkylation of stannoxides, avoiding hydrolyzable ligand substitution. The synthetic method involves the use of alkali metal stannoxides or distannoxides as starting materials, both of which exhibit high mono-organo specificity. The present invention also relates to multi-stannoxane compounds having bridging organo ligands that form C-Sn bonds with each tin atom. BACKGROUND OF THE INVENTION

[0004] Organometallic compounds provide metal ions in solution and gas phase forms for the deposition of thin films. Organotin compounds provide high EUV absorption and radiation-sensitive tin-ligand bonds, which can be used for lithographic patterning of thin films. The fabrication of semiconductor devices with continuously shrinking dimensions using EUV radiation requires new materials with a wide process window to achieve the desired patterning resolution and low defect density. SUMMARY OF THE INVENTION

[0005] In one aspect, the present invention relates to a method for synthesizing mono-organo stannoxides (or referred to as mono-organo stannoxides), the method comprising reacting MSn(OR') 3 with RX n to form R[Sn(OR') 3 n , where M is Li, Na, K, Rb or Cs; X is Cl, Br or I; and n≥1. R is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond. R' is an organic group having 1 to 10 carbon atoms. The organic group may optionally contain heteroatoms and / or unsaturated bonds.

[0006] In another aspect, the present invention relates to a method for synthesizing mono-organo stannoxides, the method comprising reacting Sn 2 (OR') 4 with RX under ultraviolet light to form RSn(OR') 3 , where X is Cl, Br or I. R is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond. R' is an organic group having 1 to 10 carbon atoms. The organic group may optionally contain heteroatoms and / or unsaturated bonds. ​

[0007] In another aspect, the present invention relates to an organometallic (or organometallic) compound represented by the formula ((R'O) 3 Sn) n -R, where n ≥ 3; R' is an organic group having 1 to 10 carbon atoms; and R is an organic group having 5 to 31 carbon atoms and forms a C-Sn bond with each Sn atom.

[0008] In another aspect, the present invention relates to a method for forming a fluorinated organometallic compound represented by the formula (CF 3 )RSn(OR') 3 , where R is an organic group having 1 to 31 carbon atoms and forms a C-Sn bond; and R' is an organic group having 1 to 10 carbon atoms. The method includes reacting (CF 3 )RX with Sn 2 (OR') 4 or MSn(OR') 3 under visible light or ultraviolet light, where X is Cl, Br, or I.

[0009] In another aspect, the present invention relates to a fluorinated organometallic compound represented by the formula (CF 3 ) 2 R 1 C-R 0 Sn(OR') 3 , where R 0 is an organic group having 1 to 31 carbon atoms and forms a C-Sn bond; R 1 is hydrogen, a halogen atom, or an organic group having 1 to 10 carbon atoms; and R' is an organic group having 1 to 10 carbon atoms. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is the 3 H NMR spectrum of KSn(OtBu) 1 in THF.

[0011] Figure 2 is the 3 Sn NMR spectrum of KSn(OtBu) 119 in THF.

[0012] Figure 3 is the 3 Sn NMR spectrum of MeSn(OtBu) 119 in THF.

[0013] Figure 4 is i the 3 Sn NMR spectrum of PrSn(OtBu)1 1H NMR spectrum.

[0014] Figure 5 is i PrSn(OtBu) 3 of 119 119Sn NMR spectrum.

[0015] Figure 6 is n PrSn(OtBu) 3 of 119 119Sn NMR spectrum.

[0016] Figure 7 is n PrSn(OtBu) 3 of 119 119Sn NMR spectrum.

[0017] Figure 8 is the 1 1H NMR spectrum of 1-but-3-enyltris(tert-butoxy)tin (MAL).

[0018] Figure 9 is the 119 119Sn NMR spectrum of 1-but-3-enyltris(tert-butoxy)tin (MAL).

[0019] Figure 10 is the 1 1H NMR spectrum of 2,2,2-trifluoroethyltris(tert-butoxy)tin (TFE).

[0020] Figure 11 is the 119 119Sn NMR spectrum of 2,2,2-trifluoroethyltris(tert-butoxy)tin (TFE).

[0021] Figure 12 is the 19 19F NMR spectrum of 2,2,2-trifluoroethyltris(tert-butoxy)tin (TFE).

[0022] Figure 13 is CF 3 CH 2 Sn(OtBu) 3 of 1 1H NMR spectrum.

[0023] Figure 14 is CF 3 CH 2 Sn(OtBu) 3 of 119 119Sn NMR spectrum.

[0024] Figure 15Shows the KSn(OtBu) after 1 hour of green LED light irradiation (A) and after 3 hours of green LED light irradiation (B) 3 and CF 3 CH 2 I solution of 119 Sn NMR spectrum.

[0025] Figure 16 Shows the KSn(OtBu) after 1 hour of green LED light irradiation (A) and after 3 hours of green LED light irradiation (B) 3 and CF 3 CH 2 I solution of 19 F NMR spectrum.

[0026] Figure 17 is the C 6 D 6 in C 4 H 8 Sn 2 (OtBu) 6 of 1 H NMR spectrum.

[0027] Figure 18 is the C 6 D 6 in C 4 H 8 Sn 2 (OtBu) 6 of 119 Sn NMR spectrum.

[0028] Figure 19 is the C 6 D 6 in (C 6 H 3 (CH 2 Sn(OtBu) 3 ) 3 of 1 H NMR spectrum.

[0029] Figure 20 is the C 6 D 6 in (C 6 H 3 (CH 2 Sn(OtBu) 3 ) 3 of 119 Sn NMR spectrum.

[0030] Figure 21 is of tris(tert - butyloxy)(3,3,3,4,4,4 - hexafluoroisobutyl)tin (HFB)1 1H NMR spectrum.

[0031] Figure 22 of 3,3,3,4,4,4-hexafluoroisobutyltris(tert-butoxy)tin (HFB) 119 119Sn NMR spectrum.

[0032] Figure 23 of 3,3,3,4,4,4-hexafluoroisobutyltris(tert-butoxy)tin (HFB) 19 19F NMR spectrum. Detailed implementation modes

[0033] A new synthetic route for organotin trialkoxide compositions has been discovered based on stannoxidation starting from Sn(II) alkoxides, and the method provides high selectivity and efficiency. In some embodiments, the new synthetic method is based on the reaction of a Sn(II) alkoxide with a potassium alkoxide to form an intermediate bimetallic alkali metal tin trialkoxide (such as a potassium tin(II) trialkoxide composition), followed by a subsequent reaction of the intermediate bimetallic composition with an alkyl halide to form a monoalkyltin trialkoxide composition. In other embodiments, an effective synthetic method is based on the reaction of a distannatetraalkoxide with an organohalide to directly synthesize an organotin trialkoxide under ultraviolet light, and the tin halide alkoxide by-product is easily separated. The methods described herein can provide high selectivity and yields, and enable the preparation of monoalkyltin trialkoxide compositions without ligand exchange or conversion reactions, for example, the conversion of a monoalkyltin triamidate to a monoalkyltin trialkoxide. The reactions described herein can be used to prepare monoalkyltin trialkoxides having primary or secondary Sn-C bonds. In some embodiments, the organic group (such as an aromatic group) can be a bridging organic ligand having a direct C-Sn bond to multiple Sn atoms (such as two, three or more tin atoms). In addition, the reactions described herein can be used to prepare organotin compounds having fluorinated organic groups, such as R F SnL 3 compounds, where R F is an alkyl group substituted by one or more fluorine atoms, especially an organotin compound having multiple trifluoromethyl (F 3 C-) groups. The resulting organotin trialkoxides may be desirable precursors for radiation-based patterning compositions, especially for effective EUV patterning.

[0034] As used herein, and generally in accordance with usage in the art, the terms "organotin", "hydrocarbyltin", and "alkyltin" may be used interchangeably, and likewise, "monoalkyl" may be used interchangeably with "monoorgano" or "monohydrocarbyl". An "alkyl" ligand indicates that tin is bonded to carbon (usually sp 3 or sp 2 hybridized) to form a bond that is generally not hydrolyzable upon contact with water. An "alkyl" group may also have internal unsaturated bonds and heteroatoms (i.e., atoms other than carbon and hydrogen) that do not participate in the bonding to tin. Similarly, reference to an alkoxide (or alcoholate) group refers to a group bonded at the oxygen atom, where an organic substituent is bonded to the oxygen. The novel synthetic method described herein produces monoalkyltin trialkoxides in high yield and with low (non-tin) metal and polyalkyl (i.e., polyhydrocarbyl) contamination after direct purification. The synthetic method is suitable for efficient scale-up for commercial production, and the reaction is simple and can be carried out as a one-pot synthesis.

[0035] Organotin compounds, particularly monoalkyltin trialkoxides and triaminide compounds, have been found to be useful as precursors for high-performance photoresists for EUV lithography. For example, the use of alkyltin compounds in high-performance radiation-based patterning compositions is described in U.S. Patent No. 9,310,684 to Meyers et al., entitled "High-Resolution Patterning Compositions Based on Organometallic Solutions", which is incorporated herein by reference. The refinement of these organometallic compositions for patterning is described in U.S. Patent No. 10,642,153 to Meyers et al., entitled "High-Resolution Patterning Compositions Based on Organometallic Solutions and Corresponding Methods" and U.S. Patent No. 10,228,618 to Meyers et al., entitled "Organotin Oxide Hydroxide Patterning Compositions, Precursors, and Patterning" (hereinafter referred to as the '618 patent) (both of which are incorporated herein by reference).

[0036] The compositions synthesized herein can be effective precursors for forming alkyltin oxo-hydroxy compositions that are advantageous for high-resolution patterning, such as in extreme ultraviolet (EUV), ultraviolet (UV), and electron beam lithography. The alkyltin precursor compositions contain groups that can be hydrolyzed with water or other suitable reagents under appropriate conditions to form a monoorganotin oxo-hydroxy patterning composition that, upon complete hydrolysis, can be represented by the formula RSnO (1.5-(x / 2)) (OH) xis represented, where 0 < x ≤ 3. Hydrolysis can be conveniently carried out to form an oxo-hydroxy composition in situ, such as during deposition and / or after the initial coating formation. Although, for example, the organotin triamidates and organotin trialkynides described in the above-mentioned '618 patent can be used under hydrolysis conditions to form radiation-sensitive coatings for patterning, it may be desirable to use organotin trialkoxides as part of the film-forming composition. The direct synthesis of organotin trialkoxides is described herein.

[0037] The mono-organotin composition can generally be represented by the formula RSnL 3 is represented, where R is an alkyl group and L is a hydrolyzable ligand. For the process of forming a coating capable of radiation patterning, L is usually hydrolyzed before or during (e.g., in situ) deposition, resulting in a coating on the substrate comprising a polymeric organotin oxo-hydroxy composition, where the Sn-R bond remains substantially intact. As a result, a radiation-patternable coating with radiation-sensitive Sn-R (Sn-C) bonds can be achieved.

[0038] The novel synthesis described herein facilitates the efficient formation of R-Sn bonds, where there is a rich choice of R groups having one or more heteroatoms, and such R groups having one or more heteroatoms can provide improvements in thermal and / or light sensitivity relative to R groups having unsubstituted alkyl groups. Without wishing to be bound by theory, it is generally believed that the presence of the R ligand hinders the formation of an extended network and condensation of the organotin film, and irradiation of the material can cause the cleavage of the Sn-C bond, which in turn allows subsequent processing to condense and / or densify the film.

[0039] During radiation patterning, the hydrolyzable ligand has generally been substantially removed to form the final patterned composition from the precursor composition. Generally, organometallic radiation-sensitive resists have been developed based on organotin compositions such as alkyltin oxide hydroxides, which are approximately represented by the formula R z SnO( 2-z / 2-x / 2 )(OH) xwhere 0 < x < 3, 0 < z ≤ 2, x + z ≤ 4, and R is a hydrocarbyl or organic group that forms a carbon bond with the tin atom. A particularly effective form of these compositions is mono-organotin oxide hydroxide, where in the above formula, z = 1, and the mono-organotin compositions are the focus of this article. In particular, R can be a moiety having 1 - 31 carbon atoms, where one or more carbon atoms are optionally substituted by one or more heteroatom functional groups (such as groups containing O, N, Si, Ge, Sn, Te, and / or halogen atoms) or an alkyl or cycloalkyl group, and the alkyl or cycloalkyl group is further functionalized with a phenyl or cyano group. In some embodiments, R can contain ≤10 carbon atoms and can be, for example, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, or tert-amyl. The R group can be a straight-chain, branched-chain (i.e., secondary or tertiary carbon at the metal-bonded carbon atom) or cyclic hydrocarbyl group. Each R group individually and typically has 1 to 31 carbon atoms, where for groups having a secondary-bonded carbon atom it has 3 to 31 carbon atoms, and for groups having a tertiary-bonded carbon atom it has 4 to 31 carbon atoms, optionally having unsaturated or aromatic carbon bonds. In particular, branched-chain alkyl ligands can be desirable for some patterning compositions. The formation of the oxo-hydroxy coating material can include depositing a tin composition having a hydrolyzable bond, such as RSnL 3 , where L is a hydrolyzable ligand such as an alkoxide, dialkylamine, acetylide, or other suitable hydrolyzable ligand. The hydrolyzable ligand can hydrolyze during the deposition of the coating to form an oxo-hydroxy network, and / or hydrolyze in the deposited coating to form an oxo-hydroxy network, i.e., complete hydrolysis after deposition. As further described in the published U.S. patent application 2022 / 00064192 to Edson et al. entitled "Method for Preparing Organotin Compositions Using Facilitating Ligands to Provide Reactants" (which is incorporated herein by reference), the applicant has developed methods for efficiently and effectively forming a wide range of patterning compositions having different R groups (which optionally have various heteroatoms) and C-Sn bonds.

[0040] The stability of the Sn-C bond can generally depend on the substitution of the α-carbon (the C bonded to Sn), and the stability generally increases as the α-carbon substitution decreases. For example, an Sn-R bond with a primary α-carbon is generally more stable than one with a secondary α-carbon, which in turn is more stable than one with a tertiary α-carbon. Additionally, some unsaturated α-carbons, such as an alkynyl C bonded to Sn (e.g., Sn-C≡C), may hydrolyze during processing, and thus may not be suitable for relying on their radiation sensitivity. The stability of the Sn-C bond can be related to dose sensitivity and / or thermal stability, such that an Sn-C bond with lower stability requires less energy to break and can thus be expected to be associated with a lower dose required to form a pattern. Additionally, the thermal stability of the Sn-C bond can depend on the α-carbon substitution, as increased α-carbon substitution generally may result in a trade-off between an undesirably lower thermal stability and a higher dose sensitivity. Thus, it is desirable for novel organotin compositions to have both high thermal stability and high dose sensitivity.

[0041] The process of treating an organotin precursor composition to provide an organotin oxo-hydroxy coating generally involves hydrolyzing one or more RSnL 3 compositions to provide one or more related organotin oxo-hydroxy compositions. The hydrolysis can be carried out prior to the deposition process to generate soluble organotin oxo-hydroxy species (i.e., clusters, oligomeric species, etc.). These soluble organotin oxo-hydroxy species can then be dissolved and / or dispersed into a suitable solvent to form an organotin photoresist solution, which can then be used to form an organotin oxo-hydroxy coating capable of radiation patterning. Alternatively, the organotin precursor composition can be directly dissolved into a suitable solvent to form a photoresist solution, which can then be used to form an organotin oxo-hydroxy coating capable of radiation patterning. During the substrate coating process, such as during solution deposition or during vapor deposition, the organotin composition can also be hydrolyzed in situ with water (which can be ambient water vapor). Various processing options are further described in the above-mentioned '684 patent and '618 patent.

[0042] For an organotin photoresist precursor composition in which one or more organotin compounds are dissolved into a solvent for spin coating, the use of an organotin trialkoxide (RSnL 3 , L = OR’) is relative to other RSnL 3 compositions (e.g., an organotin triamido compound, L = NR’ 2) can be desirable. Some advantages of organotin trialkoxide compositions are, for example: the production of relatively more benign by-products (such as alcohols) compared to the production of gaseous products (such as amines), which gaseous products may cause contamination, environmental health and safety (EHS), and similar problems in the wafer track and / or the fab. Organotin trialkoxides also have a relatively high vapor pressure and low melting point, which makes them compounds of interest for use in deposition processes for preparing coatings capable of radiation patterning.

[0043] The synthesis of organotin trialkoxide compounds has been previously described, such as in the prior patent applications of the present applicant. However, these reactions that provide monoalkyltin trialkoxides as products typically involve the conversion of non-alkoxide alkyltin compounds to alkyltin alkoxides rather than direct synthesis. In other words, organotin trialkoxides are typically synthesized by ligand substitution reactions. For example, organotin trialkoxides can be prepared from the corresponding organotin trichlorides by reaction with alkali metal alkoxides (alkali metal alcoholates) (such as KOR’, NaOR’, etc.) according to the following reaction:

[0044] , (1)

[0045] Using this synthesis scheme, the possible product space of organotin trialkoxides is thus practically limited based on the availability and purity of the corresponding organotin trichlorides. Organotin trichlorides are typically synthesized by the well-known Kocheskov Reaction, in which tetraalkyltin R 4 Sn is used as a starting material for synthesizing other organotin halides, which other organotin halides are produced by redistribution reactions with SnCl 4 . This reaction is known to be non-selective and particularly sensitive to stoichiometry, and typically produces some off-target and undesired R n SnCl 4-n product distribution. For example, to synthesize RSnCl 3 , a mixture of SnCl 4 and R 4 Sn is reacted in a 3 to 1 ratio to produce RSnCl 3 as the main target product, but the reaction produces significant amounts of R 2 SnCl 2 and R 3 SnCl as by-products. For semiconductor applications that require high-purity compounds to achieve low-defect processing and commercial viability, in RSnCl 3One or more purification steps may be required to further purify and / or isolate the compound before it is converted to the trialkoxide, and the purification itself may involve a great deal of work. The synthetic methods described herein alleviate the need for highly pure organotin trichloride starting materials in the synthesis of organotin trialkoxides.

[0046] Other methods for preparing organotin trialkoxides involve converting organotin triamidates to organotin trialkoxides by the following reaction:

[0047] .(2)

[0048] Although the reaction is relatively simple, the application of the method may be limited by various factors, such as it being exothermic and potentially leading to the decomposition of the reactants and / or products, as well as the high cost due to the need to first synthesize the corresponding organotin triamidate. Although the applicant has previously described synthetic techniques for preparing a variety of organotin triamidates, there is still a need to obtain methods for directly synthesizing organotin trialkoxides without first obtaining an organotin starting material with the desired R ligand characteristics. The direct synthesis of the target organotin trialkoxide RSn(OR’) 3 is desirable and is described herein.

[0049] Direct synthesis of organotin trialkoxides

[0050] Two related synthetic techniques are described for the direct synthesis of organotin trialkoxides. As illustrated, both methods involve the reaction of an organohalide such as an alkyl halide (RX) with a stannoxide (or stannolate) compound to form an Sn-R bond. The stannoxide can be ditin tetraalkoxide (Sn 2 (OR') 4 ) or an alkali metal stannoxide (e.g., MSn(OR’) 3 ). In the first method, ditin tetraalkoxide is reacted with an organohalide, typically in the presence of ultraviolet or monochromatic visible light, to form a monoalkyltin trialkoxide RSn(OR’) 3 . In the second method, an alkali metal stannoxide is reacted with an organohalide to form the corresponding organotin trialkoxide with low tin contaminant formation.

[0051] Ditin tetraalkoxide (Sn 2 (OR’) 4 ) and alkali metal stannoxides (MSn(OR’) 3) can be prepared using methods known in the literature, such as the article by Veith et al. entitled "Alkoxistannate, II Tri(tert-butoxi)alkalistannates(II): Synthesis and Structures" (Z. Naturforsch. 41b, 1071 - 1080 (1986)) (hereinafter referred to as the Veith article), which is incorporated herein by reference. The Veith article does not disclose the use of Sn 2 (OR’) 4 or MSn(OtBu) 3 as a further reactant to form a specific reaction of an alkyltin trialkoxide (e.g., RSn(OtBu) 3 ). The Veith article discloses the use of Sn 2 (O t Bu) 4 to synthesize MSn(OtBu) 3 . As illustrated herein, MSn(OtBu) 3 is synthesized from SnCl 2 and M(OtBu) in a two-step reaction. After the first step, the precipitated MCl (KCl) is removed, but no further purification is required.

[0052] As described herein and in the following examples, monoalkyltin trialkoxides can be synthesized by the following overall reaction:

[0053] , (3)

[0054] wherein M is generally an alkali metal, such as Li, K, Na, Cs or Rb. R’ is generally an organic group having ≤10 carbon atoms, and OR’ can generally be selected according to the desired properties of the product monoalkyltin trialkoxide RSn(OR’) 3 such as stability, melting point, solubility, ease of purification, etc. In some embodiments, M is K. In some embodiments, OR’ is tert-butoxy (OtBu). In some embodiments, OR’ is tert-amyloxy (OtAm). The RX compound is selected to provide the desired organic group ligand R for the monoorganic tin product. The wide availability of the RX compound as a reactant and the general reactivity of the compound in the corresponding reaction provide the ability to introduce a wide range of alkyl ligands into the product monoalkyltin product. X can generally be a halogen selected from I, Br or Cl.

[0055] The reaction of formula (3) can be extended for the synthesis of multi-tin products with bridged organic group ligands.

[0056] , (4)

[0057] where n ≥ 1, such as 1, 2, 3, 4 or greater than 4, and M is generally an alkali metal as described above. Usually, as long as reasonable polyhalide reactants are available, there is no clear limit to the number of tin atoms that can be bridged in this way. In some embodiments, n can be from 2 to about 12. R, X, and R' are as specified in the previous paragraphs. For mono-tin or multi-tin embodiments, multiple different R' groups can be used if desired.

[0058] For the reactions described herein, primary and secondary R groups (i.e., R groups having a C atom at the 1° or 2° position for forming a C-Sn bond) are particularly effective in forming the desired RSn(OR’) 3 in terms of the composition through the synthetic routes described herein. Usually, the R ligand is an organic group ligand having 1 - 31 carbon atoms, where one or more carbon atoms are optionally substituted by one or more (one of more) various heteroatom functional groups containing O, N, Si, and / or halogen atoms, or an alkyl or cycloalkyl group, and the alkyl or cycloalkyl group is further functionalized by a phenyl or cyano group and has optional unsaturated carbon-carbon or heteroatom bonds. In particular, as shown in the examples herein, olefin R ligands having unsaturated carbon bonds can also be prepared, such as R ligands having one or more C=C bonds. Additionally, poly-tin compounds having two, three, or more Sn atoms bridged by a shared R group can be prepared using polyhalide reactants by the novel synthetic methods described herein. In some embodiments, as further described below, the presence of a catalyst during the reaction for forming monoalkyltin trialkoxide can be desirable.

[0059] In some embodiments, the R ligand can contain heteroatom functional groups containing O, N, Si, and / or halogen atoms. In some embodiments, the R ligand is fluorinated. Fluorine atoms can desirably replace H atoms within the R ligand due to their higher EUV absorption. Additionally, the presence of F atoms within the R ligand can increase the hydrophobicity of the ligand, thereby increasing the developer contrast between the irradiated and non-irradiated regions of the film.

[0060] In some embodiments, the fluorinated R ligand can contain 2 to 10 carbon atoms and more than two -CF 3 groups, such as in the hexafluorobutyl (HFB) compound as described in the examples herein. In some embodiments, the R ligand can contain a tertiary carbon having a C-F bond, such as -CFR 2, where R is a hydrocarbyl group having 1 to 10 carbon atoms, such as in the HFP compounds described in the examples herein.

[0061] In some embodiments, the R ligand can include a bridging hydrocarbyl group shared between two, three, or more Sn atoms. The bridging R ligand can generally include a straight-chain, branched-chain, cyclic, and / or aromatic hydrocarbyl group having 1 to 31 carbon atoms.

[0062] The alkali metal stannous trialkoxide intermediate MSn(OR’) 3 (i.e., a bimetallic alkoxide of Sn(II)) is a useful reagent for forming organotin trialkoxides and can be prepared according to the following reaction:

[0063] . (4)

[0064] The alkali metal M can generally be selected from Li, Na, K, Cs, or Rb. In some embodiments, M is K. In some embodiments, M is Li or Na. The MSn(OR’) 3 compound can be separated, purified, and used as a solid reagent for synthesis, and its preparation is included in the examples herein.

[0065] When reacted with an organohalide at an appropriate temperature and conditions, an oxidative addition reaction can occur, where a carbon-tin bond is formed, and potassium halide and RSn(OR’) 3 are rapidly formed. As illustrated below, the reaction proceeds in two steps, where first 2 equivalents of MOR' are added to precipitate MCl, and then MCl can be removed. An additional amount of MOR' is added, and considering the loss caused by filtration for removing the precipitated MCl, slightly less than one equivalent can be added. Generally, the precipitated alkali metal halide such as potassium halide salt can alternatively be filtered off, and / or the RSn(OR’) 3 product can be purified and collected, such as by distillation.

[0066] For some R groups, such as fluorinated alkyl groups, it has been found that the corresponding R F Sn(OR’) 3 composition can be synthesized in the presence of ultraviolet or visible light without using an alkali metal stannoxide composition according to the following reaction, i.e., directly from Sn(OR) 2 ([Sn(OR’) 2 ) 2 :

[0067] , (5)

[0068] A disn tin by - product (Sn 2 X 2 (OR') 2 ) that is usually formed as a solid precipitate and can be separated by filtration or other suitable techniques. Although described as a reaction for fluorinating organic - based ligands, the reaction can be applied more broadly as needed.

[0069] In the examples herein, the synthesis of fluoroalkyltin trialkoxides is described, where R F = trifluoroethyl (TFE, CF 3 CH 2 -), R' = tert - butyl, and X = halogen (Cl, Br, I). Although not wishing to be bound by theory, the reaction with the fluoroalkyl group is thought to involve a radical mechanism that can be promoted by irradiation with suitable ultraviolet or visible light. Notably, the reaction can be carried out under ultraviolet or visible light irradiation in the absence of bimetallic tin(II) alkoxides. These reactions can also be carried out using alkali metal tin trialkoxides and are also promoted by visible light or ultraviolet light irradiation. Suitable light sources, such as LEDs, lasers, bulbs, etc., can be used to provide ultraviolet and / or visible light for the reaction. The light source can generally provide light with a wavelength of 200 nm to 700 nm, and it is generally desirable that the selected wavelength has sufficient transmittance to pass through one or more reaction vessels (i.e., glassware) and be sufficiently absorbed by the substances in the reaction medium. In some embodiments, the light source can be monochromatic.

[0070] The reaction is generally carried out in a dry organic solvent under an anaerobic or oxygen - lean atmosphere (such as a nitrogen - purged atmosphere). The solvent can be chosen to obtain the solubility of the various components. Due to the interaction of the solvent with the metal ions, the choice of solvent can be based at least in part on the reaction rate in the selected solvent, which can be evaluated empirically. If different solvents are chosen, they are generally miscible. Both aprotic polar and non - polar solvents are generally available, such as alkanes (e.g., hexane, pentane), ethers (e.g., dimethyl ether, diethyl ether), tetrahydrofuran (THF), acetone, toluene, acetonitrile, and mixtures thereof. The solvent should generally be chosen to be inert to the reactants, intermediates, and products. If multiple solvents are used, for example, to introduce different reactants, the solvents should generally be miscible with each other.

[0071] In the bimetallic MSn(OR') 3During the reaction of the compound with the alkyl halide RX compound, a catalyst containing halide may be present. The catalyst generally may include tetraalkyl (quaternary) ammonium salts, tetraalkylphosphonium salts, or mixtures thereof, such as tetrabutylammonium iodide, tetrabutylammonium bromide, tetrabutylammonium hexafluorophosphate, and / or tetraphenylphosphonium chloride. Since the catalyst is not consumed, the amount of the catalyst can be selected as needed to affect the reaction rate. Generally, the amount of the catalyst is part of the stoichiometric amount.

[0072] Using MSn(OR’) 3 The reaction using as a raw material can generally be carried out in a one-pot process without any intermediate steps (such as separation, purification, transfer, etc.). After the reaction between the bimetallic alkoxide MSn(OR’) 3 and the alkyl halide, the organotin alkoxide product in pure form can be obtained by filtration and / or distillation. Using a polyhalide organic reactant, a bridged organic group R(Sn(OR') 3 ) n can be formed, where n > 1, and where the organic group R has Sn-C bonds with n Sn atoms, and a tris-tin product is illustrated.

[0073] The reactions described herein are highly selective for forming mono-organotin trialkoxide compounds, and the organic halide can generally be present as a reactant in a molar excess amount relative to the MSn(OR’) 3 composition. However, for forming multi-tin products with bridged ligands, a stoichiometric amount of the polyhalide organic reactant can be used. Similarly, for the reaction involving Sn 2 (OR') 4 shown in formula (5) above for directly forming organotin trialkoxide, the reaction is also very specific for mono-organic products. In some embodiments, the organic halide can be present in an amount up to about 2 molar equivalents relative to the MSn(OR’) 3 (or Sn 2 (OR') 4 ) compound, in other embodiments in an amount up to about 1.6 molar equivalents relative to the MSn(OR’) 3 (or Sn 2 (OR') 4 ) compound, in other embodiments in an amount up to about 1.3 molar equivalents relative to the MSn(OR’) 3 (or Sn 2 (OR') 4 ) compound, and in further embodiments in an amount up to about 1 molar equivalent relative to the MSn(OR’) 3 (or Sn 2 (OR') 4) The compound is present in an amount of up to about 1.1 molar equivalents. In some embodiments, the organic group halide and MSn(OR') 3 (or Sn 2 (OR') 4 ) compound can be present in an amount of approximately stoichiometric. Note that for reactions based on Sn 2 (OR') 4 , the production of the removed Sn by-product results in a limit of 50% yield based on tin, which is not a limit for reactions involving MSn(OR') 3 reactants. Those of ordinary skill in the art will recognize that additional ranges of the relative reactant amounts within the above-specified ranges are contemplated and are within the present disclosure.

[0074] In some embodiments, the reaction can generally be carried out at a temperature below about 100 °C, in other embodiments below about 80 °C, and in further embodiments below about 60 °C. In some embodiments, the reaction can be carried out at room temperature. In some embodiments, the reaction can be carried out under ultraviolet light irradiation. In embodiments where ultraviolet light irradiation is carried out during the reaction, the reaction can be carried out with heating or without heating. In some embodiments, the reaction can be carried out with cooling and at a temperature of about -80 °C to about -60 °C, in some embodiments at about -60 °C to about -40 °C, in other embodiments at about -40 °C to about -20 °C, and in other embodiments at about -20 °C to about 20 °C. In some embodiments, the ultraviolet light irradiation can be carried out at a wavelength of 365 nm. In some embodiments, the ultraviolet light irradiation can be carried out at a wavelength of 254 nm. In some embodiments, the reaction can be carried out under monochromatic visible light irradiation. The irradiation provided during the reaction can generally be carried out at a wavelength that is suitably transparent for the reaction apparatus (e.g., glassware, containers, etc.) such that significant absorption can occur to drive the reaction. The reaction is generally stirred during the duration of the reaction. It can be through 1 H and / or 119The reaction is monitored by Sn NMR analysis of the reaction mixture to determine when the reaction has reached substantial completion. In some embodiments, the reaction can proceed for about 5 days, in other embodiments for about 3 days, in other embodiments for about 1 day, and in additional embodiments for about 1 hour. One of ordinary skill in the art will recognize that additional time and temperature ranges within the above-specified ranges are contemplated and are within the scope of the present disclosure. The ideal reaction time and temperature will generally depend on the characteristics of the organic halide (RX). The reactivity of organic halides generally follows the order: I > Br > Cl in order of X, and 1° > 2° >> 3° in order of the carbon forming the C-X bond. Suitable reaction times and temperatures can be determined by routine experimentation based on the teachings herein. The reaction is typically carried out under an inert atmosphere such as N 2 or Ar. One of ordinary skill in the art will recognize that additional process condition ranges within the above-specified ranges are contemplated and are within the scope of the present disclosure.

[0075] Once the product is formed, the organotin trialkoxide can be purified. The purification depends on the nature of the product but generally involves separating the desired product from by-products and any unreacted reagents that may be present. Purification can typically be achieved by methods known in the art. Typical purification means can include filtration, recrystallization, extraction, distillation, sublimation, combinations thereof, etc. A commercial filter is generally used to filter the crude product mixture to remove insoluble contaminants and / or by-products from the solution containing the desired product, e.g., metal halide salts such as KI. Recrystallization can be used to purify a solid compound by forming a saturated solution upon heating and then allowing it to cool. Extraction techniques can include, for example, liquid-liquid extraction, where two immiscible solvents with different densities are used to separate the desired compound based on the relative solubility of the desired compound. Purification can also include removing any volatile compounds (including solvents) from the product mixture by drying using heat and / or exposure to a vacuum. For products with a significant vapor pressure, it may be desirable to purify the product by vacuum distillation or, if needed, fractional distillation designed to achieve high purity. See U.S. Published Patent Application 2020 / 0241413 to Clark et al. entitled “Monoalkyl Tin Trialkoxides and / or Monoalkyl Tin Triamides With Low Metal Contamination and / or Particulate Contamination and Corresponding Methods,” which is incorporated herein by reference. In some cases, the product can be purified by sublimation techniques, where heating the crude product mixture and / or applying a reduced pressure results in the collection of the solid product, which can be purified by sublimation of the solid product and collected by deposition onto a target surface such as a finger cooler. Purification of a ditin compound by sublimation is described in the examples herein.

[0076] The organotin trialkoxide RSnL described herein can be further processed 3 (L = OR’) to form the corresponding organotin compound with a different hydrolyzable ligand L. In one example, the alkoxide ligand can be replaced with a different alkoxide ligand, e.g., by hydrolysis and / or alcoholysis to replace one or more OR’ ligands with OR” ligands. The organotin trialkoxide can also be converted to an organotin triamide (RSnL 3 , L = NR” 2 ), e.g., by reacting the organotin trialkoxide with LiNR” 2or a reaction similar to metal amides for conversion. In other examples, the alkoxide ligand can be replaced by acetylide, amidinate, carboxylate, etc.

[0077] Hydrolyzable ligands can generally be selected based on considerations of handling or usage, such as in the desired mode of processing the RSnL 3 composition into a film capable of radiation patterning. For example, while organotin trialkoxides (RSn(OR’) 3 , L = OR’) may be ideal for forming a resist solution, organotin triamides (RSn(NR” 2 )) 3 ) are particularly ideal for use in vapor deposition applications due to their generally higher vapor pressure and higher reactivity. In either case, i.e., when L = OR’ or L = NR”, the hydrolysis and condensation reactions that occur during the deposition process result in the formation of a similar organotin oxide hydroxide film composition in which the Sn-C bond is retained, and Sn-O-Sn bonds and Sn-OH bonds are formed by the hydrolysis of the Sn-L bond.

[0078] Coatings, depositions, and related compositions

[0079] The organotin precursor compositions described herein can be effectively used for radiation patterning, especially EUV patterning. The ability to have greater flexibility in the choice of R ligands allows for further improvement of the patterning results and the design of ligands to be particularly effective for specific applications. Generally, any suitable coating process can be used to deliver the precursor solution to the substrate. Suitable coating methods can include: for example, solution deposition techniques such as spin coating, spray coating, dip coating, knife coating, printing such as inkjet printing and screen printing, and so on. As discussed in the ’618 patent cited above, a variety of precursors are also suitable for vapor deposition onto the substrate. For some R ligand compositions and / or specific process considerations, vapor deposition can be used to prepare radiation-sensitive coatings.

[0080] After preparing the desired organotin precursor, the precursor can be dissolved in a suitable solvent to prepare a precursor solution, such as an organic solvent, for example, alcohols, aromatic and aliphatic hydrocarbons, esters, or combinations thereof. In particular, suitable solvents include: for example, aromatic compounds (e.g., xylene, toluene), ethers (anisole, tetrahydrofuran), esters (propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate), alcohols (e.g., 4-methyl-2-pentanol, 1-pentanol, 1-butanol, methanol, isopropanol, 1-propanol), ketones (e.g., methyl ethyl ketone), mixtures thereof, and so on. Generally, the choice of organic solvent may be affected by solubility parameters, volatility, flammability, toxicity, viscosity, and possible chemical interactions with other processing materials.

[0081] Typically, one or more organotin precursors can also be dissolved in a solvent mixture to prepare a precursor solution. Some solvent mixtures that can be used to form an organotin photoresist solution have been described in the published U.S. patent application 2023 / 0143592, entitled "Stability-Enhanced Organotin Photoresist Compositions" by Jiang et al., which is incorporated herein by reference. It may be desirable to dissolve one or more organotin precursors in a solvent mixture containing a primary alcohol. In some embodiments, the solvent can include a primary alcohol, such as methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, etc. In some embodiments, the solvent can include a mixture of two alcohols. In other embodiments, the solvent can include a mixture of an alcohol and an ester. After the components of the solution are dissolved and combined, the properties of the material may change due to local in-situ hydrolysis, hydration, and / or condensation.

[0082] The organotin precursor can be dissolved in a solvent at a concentration that provides an Sn concentration suitable for forming a coating of a suitable thickness for processing. The concentration of the substances in the precursor solution can be selected to achieve the desired solution physical properties. In particular, for certain coating methods, such as spin coating, where thinner coatings can be achieved using reasonable coating parameters, a lower overall concentration can result in desirable solution properties. It may be desirable to use thinner coatings to achieve ultra-fine patterning and reduce material costs. Generally, the concentration can be selected to be suitable for the selected coating method. Coating properties are further described below. Generally, the tin concentration includes from about 0.005 M to about 1.4 M, in additional embodiments from about 0.02 M to about 1.2 M, and in additional embodiments from about 0.1 M to about 1.0 M. Those of ordinary skill in the art will recognize that additional tin concentration ranges within the above-specified ranges are contemplated and within the scope of the present disclosure.

[0083] In some embodiments, an improved photosensitive precursor composition can be present in a composition having one or more organotin compositions such as R n SnL 4-nIn a blend solution of it and its hydrolysis products, where R is selected from various moieties described in detail herein and explicitly set forth above. Such blend solutions can be adjusted to optimize various performance considerations, such as solution stability, coating uniformity, and patterning performance. In some embodiments, the improved photosensitive composition can account for at least 1 mol% of the desired component Sn in the blend solution, in additional embodiments at least 10 mol% of Sn in the blend solution, in additional embodiments at least 20 mol% of Sn in the blend solution, and in additional embodiments at least 50 mol% of the specific desired component Sn in the blend solution. Additional mole % ranges of the improved photosensitive composition within the defined scope of the blend solution are contemplated and within the present disclosure. The hydrolysable ligand L can be hydrolyzed during or after deposition, such as by hydrolysis using water vapor.

[0084] Generally due to their high vapor pressure, the organotin compositions described herein can be used as precursors for forming coatings by vapor deposition. Vapor deposition methods generally include chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), and their variants. In a typical vapor deposition process, the organotin composition can react with small molecule gas-phase reagents (such as H 2 O, O 2 、H 2 O 2 、O 3 、CH 3 OH、HCOOH、CH 3 COOH, etc.), and the small molecule gas-phase reagents serve as sources of O and H for preparing radiation-sensitive organotin oxide and oxide hydroxide coatings. Water vapor can be provided by ambient air, delivered in vapor form, or otherwise provided in the form of a suitable liquid or gas-phase composition. Wu et al. have described in PCT application No. PCT / US2019 / 031618, entitled "Method for Preparing a Hard Mask Capable of EUV Patterning" (which is incorporated herein by reference), specific apparatuses for vapor deposition of radiation-sensitive organotin coatings. The preparation of radiation-sensitive organotin coatings can generally be achieved by reacting a volatile organotin precursor RSnL 3 with small gas-phase molecules. The reaction can include hydrolysis / condensation of the organotin precursor to hydrolyze the hydrolysable ligand while leaving the Sn-C bond substantially intact. In some embodiments, two or more different RSnL 3 compounds having different R and / or L ligands can be used to form a final film containing a mixture of RSn species.

[0085] Regardless of whether deposition is by solution deposition or by vapor deposition, hydrolysis of the hydrolysable ligand can result in the formation of RSnOx OH 3-2x The oxo-hydroxy network represented. Generally, radiation exposure and patterning are performed using a hydrolyzed coating.

[0086] An overview of a representative method of radiation-based patterning, such as extreme ultraviolet (EUV) lithography, deposits or coats a photoresist material on a substrate as a thin film, performs a pre-exposure bake, exposes using a radiation pattern to create a latent image, performs a post-exposure bake, and then develops with a liquid (generally an organic solvent) to produce a developed resist pattern. Fewer steps can be used if desired, and additional steps can be used to remove residues to improve pattern fidelity.

[0087] The thickness of a radiation-patternable coating can depend on the desired process. For use in single-patterning EUV lithography, the coating thickness is typically selected to produce a pattern with a low defect rate and patterning reproducibility. In some embodiments, a suitable coating thickness can be from 0.1 nm to 100 nm, in other embodiments about 1 nm to 50 nm, and in other embodiments about 2 nm to 25 nm. Those of ordinary skill in the art will understand that additional coating thickness ranges are contemplated and within the scope of this disclosure.

[0088] The coating thickness of a radiation-patternable coating prepared by a vapor deposition technique can generally be controlled by appropriate selection of the reaction time or the cycle of the process. The thickness of a radiation-patternable coating can depend on the desired process. For use in single-patterning EUV lithography, the coating thickness is typically selected to produce a pattern with a low defect rate and patterning reproducibility. In some embodiments, a suitable coating thickness can be from 0.1 nm to 100 nm, in other embodiments about 1 nm to 50 nm, and in other embodiments about 2 nm to 25 nm. Those of ordinary skill in the art will understand that additional coating thickness ranges are contemplated and within the scope of this disclosure.

[0089] The substrate generally provides a surface on which the coating material can be deposited, and it can include multiple layers, where the surface refers to the uppermost layer. There is no particular limitation on the substrate, and it can comprise any reasonable material, such as silicon, silicon dioxide, other inorganic materials such as ceramics, and polymeric materials.

[0090] After deposition and formation of a radiation-patternable coating, further processing can be employed before exposure to radiation. In some embodiments, the coating can be heated to from 30 °C to 300 °C, in other embodiments to from 50 °C to 200 °C, and in yet other embodiments to from 80 °C to 150 °C. The heating can be carried out for from about 10 seconds to about 10 minutes in some embodiments, for from about 30 seconds to about 5 minutes in other embodiments, and for from about 45 seconds to about 2 minutes in yet other embodiments. Other ranges of temperature and heating times within the stated ranges above are contemplated and envisioned.

[0091] Patterning of compositions

[0092] The radiation can generally be directed onto the coated substrate through a mask, or a radiation beam can be scanned controllably over the substrate. Generally, the radiation can include electromagnetic radiation, an electron beam (β-radiation), or other suitable radiation. Generally, the electromagnetic radiation can have a desired wavelength or wavelength range, such as visible light radiation, ultraviolet radiation, or X-ray radiation. The resolution achievable for the radiation pattern generally depends on the radiation wavelength, and generally, the shorter the wavelength of the radiation used, the higher the resolution of the pattern that can be achieved. Thus, it can be desirable to use ultraviolet light, X-ray radiation, or an electron beam to achieve particularly high-resolution patterns.

[0093] According to international standard ISO 21348 (2007), which is incorporated herein by reference, ultraviolet light extends between wavelengths greater than or equal to 100 nm and less than 400 nm. A krypton fluoride laser can be used as a source of 248 nm ultraviolet light. The ultraviolet range can be subdivided in a number of ways under accepted standards, such as extreme ultraviolet (EUV) from greater than or equal to 10 nm to less than 121 nm and far ultraviolet (FUV) from greater than or equal to 122 nm to less than 200 nm. The 193 nm line from an argon fluoride laser can be used as a radiation source in the FUV. EUV light at 13.5 nm has been used in lithography and this light is generated by a Xe or Sn plasma source excited using a high-energy laser or a discharge pulse. Soft x-rays can be defined as from greater than or equal to 0.1 nm to less than 10 nm.

[0094] Based on the design of the coating material, a large material property difference can exist between the irradiated area with the condensed coating material and the un-irradiated coating material with substantially intact Sn-C bonds. For embodiments in which post-irradiation heat treatment is used, the post-irradiation heat treatment can be carried out at a temperature of about 45 °C to about 250 °C, in another embodiment about 50 °C to about 190 °C and in another embodiment about 60 °C to about 175 °C. The post-exposure heating can generally be carried out for at least about 0.1 minute, in another embodiment for about 0.5 minute to about 30 minutes, and in another embodiment for about 0.75 minute to about 10 minutes. Those of ordinary skill in the art will recognize that additional post-irradiation heating temperature and time ranges within the above-specified ranges are contemplated and are within the scope of this disclosure. As described in the following section, this large material property difference further facilitates the formation of high-resolution lines with smooth edges in the developed pattern.

[0095] For negative tone imaging, the developer can be an organic solvent, such as the solvent used to form the precursor solution. Generally, the developer selection may be influenced by the solubility parameters for both the irradiated and un-irradiated coating materials, as well as the volatility, flammability, toxicity, viscosity of the developer, and possible chemical interactions with other process materials. In particular, suitable developers include: for example, alcohols (e.g., 4-methyl-2-pentanol, 1-butanol, isopropyl alcohol, 1-propanol, methanol), ethyl lactate, ethers (e.g., tetrahydrofuran, dioxane, anisole), esters (propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate), ketones (pentanone, hexanone, 2-heptanone, octanone), etc., and mixtures thereof. Suitable developers are further described in the published U.S. patent application No. 2020 / 0326627, entitled "Organometallic Photoresist Developer Compositions and Processing Methods" by Jiang et al., which is incorporated herein by reference, and such developers can generally include solvent blends of ketones, alcohols, ethers, esters, and water, glycol ethers, pyrrolidone, lactone, carboxylic acid, or combinations thereof. The development can be carried out for about 5 seconds to about 30 minutes, in another embodiment for about 8 seconds to about 15 minutes, and in another embodiment for about 10 seconds to about 10 minutes. Those of ordinary skill in the art will recognize that additional ranges within the above-specified ranges are contemplated and are within the scope of this disclosure.

[0096] In the case of a weaker developer (e.g., a dilute organic developer or composition where the coating has a lower development rate), a higher temperature development process can be used to increase the rate of the process. In the case of a stronger developer, the temperature of the development process can be lower to reduce the rate and / or control the kinetics of development. Generally, the temperature of development can be adjusted between appropriate values that are consistent with the volatility of the solvent. Additionally, during development, sonication can be used to disperse the developer and the dissolved coating material near the developer-coating interface. Any reasonable method can be used to apply the developer to the patterned coating material. For example, the developer can be sprayed onto the patterned coating material. Additionally, spin coating can be used. For automated processing, the puddle method can be used, which involves pouring the developer onto the coating material in a stationary form. If desired, spin cleaning and / or drying can be used to complete the development process. Suitable cleaning solutions include, for example, ultrapure water, aqueous solutions of tetraalkylammonium hydroxide, methanol, ethanol, propanol, and combinations thereof. After the image is developed, the coating material remains on the substrate as a pattern.

[0097] In some embodiments, a solventless (dry) development process can be carried out by using an appropriate thermal development or plasma development process (such as those described by Tan et al. in PCT patent application number PCT / US2020 / 039615, entitled "Photoresist Development Using Halide Chemistry", which is incorporated herein by reference). For an organotin-based photoresist coating, dry development can be carried out by using a halogen-containing plasma and gas (e.g., HBr and BCl 3 ). In some cases, dry development can offer advantages over wet development, such as reduced pattern collapse, reduced scum, and fine control over the developer composition (i.e., the plasma and / or etch gas).

[0098] After the development step is completed, the coating material can be heat-treated to further condense the material and further dehydrate, densify, or remove residual developer from the material. This heat treatment can be particularly desirable for embodiments in which the oxide coating material is incorporated into the final device, although for some embodiments in which the coating material is used as a resist and is ultimately removed, heat treatment may be required if stabilization of the coating material is desired to facilitate further patterning. In particular, the patterned coating material can be baked under conditions where the patterned coating material exhibits a desired level of etch selectivity. In some embodiments, the patterned coating material can be heated to a temperature of about 100 °C to about 600 °C, in additional embodiments about 175 °C to about 500 °C, and in additional embodiments about 200 °C to about 400 °C. The heating can be carried out for at least about 1 minute, in other embodiments about 2 minutes to about 1 hour, and in additional embodiments about 2.5 minutes to about 25 minutes. The heating can be carried out in air, vacuum, or an inert gas environment such as Ar or N 2 2. This will be recognized by those of ordinary skill in the art, and ranges of additional heat treatment temperatures and times within the above-specified ranges are contemplated and within the scope of this disclosure. Similarly, non-heat treatments (including blanket UV exposure or exposure to an oxidative plasma such as O 2 2) can be used for similar purposes.

[0099] Examples

[0100] Example 1. (1) Synthesis of potassium tris(tert-butoxy)stannate (KSn(OtBu) 3 ) and (2) conversion to methyl tris(tert (butyloxy)tin

[0101] This example describes a method for the one-pot direct synthesis of organotin trialkoxides. The method is based on the following two reactions, where the second reaction is carried out at room temperature and a tetraalkyl(quaternary)ammonium salt is used as a catalyst. All experiments described in the examples were carried out in an oxygen-depleted inert atmosphere (such as nitrogen, argon, or other inert atmospheres).

[0102] (1)

[0103] (2)

[0104] (1) Tin dichloride and anhydrous tetrahydrofuran were added to a reaction vessel under an inert atmosphere to form a concentration of approximately 0.07 g SnCl 2A solution in / ml of THF. The solution was mixed while cooling to 4 °C. Then, potassium tert-butoxide in an amount of 2.0 molar equivalents relative to the initial amount of stannous chloride was slowly added. The reaction mixture was maintained at a temperature below 60 °C. After completion of the addition step, the reaction mixture was stirred for 1 hour. The resulting white precipitate was removed by filtration through a bed of diatomaceous earth, and the filtrate was collected. Additional potassium tert-butoxide (0.9 molar equivalent relative to the initial amount of stannous chloride) was slowly added to the filtrate. Considering process practicability, 0.9 molar equivalent relative to the initial tin is approximately the molar equivalent relative to the persistent tin. The reaction mixture was maintained at a temperature below 60 °C. Volatiles were removed under vacuum, and the product was recrystallized from a 1:1 mixture of THF / toluene (~2 mL / g of product) at -20 °C to obtain KSn(OtBu) 3 , a white crystalline solid.

[0105] Figure 1 Shows KSn(OtBu) 3 of 1 1H NMR spectrum. Having a single chemical shift: 1 1H NMR (400 MHz, THF) δ 1.17 ppm (s). Figure 2 Shows KSn(OtBu) 3 of 119 119Sn NMR spectrum. Having a single chemical shift: 119 119Sn NMR (149 MHz, THF) δ -183 ppm.

[0106] (2) The KSn(OtBu) 3 product (one molar equivalent) from (1) was mixed with 0.5 molar equivalent of tetrabutylammonium iodide ((n-Bu) 4 4N(I)) as a catalyst, and toluene was added to the reaction vessel under an inert atmosphere to form a solution with a concentration of approximately 0.10 g KSn(OtBu) 3 / ml of toluene. The solution was mixed at room temperature. Then, methyl iodide (CH 3 3I) in an amount of 1.5 molar equivalents relative to the amount of KSn(OtBu) 3 was slowly added, and the reaction was stirred at room temperature for 1 hour. Volatiles were removed under vacuum, and the remaining residue was filtered through a bed of diatomaceous earth using pentane. The filtrate was evacuated and distilled to obtain MeSn(OtBu) 3 , a clear yellow liquid. Figure 3 Shows the product MeSn(OtBu) 3 of 119 119Sn NMR spectrum, which shows a singlet: 119Sn NMR (149 MHz, neat) δ -175). A single tin environment indicates that in the conversion of KSn(OtBu) 3 to MeSn(OtBu) 3 no tin by-products were found.

[0107] This example demonstrates a two-step one-pot method for the direct synthesis of organotin trialkoxides with primary Sn-C bonds, which has high single-organo specificity. The method uses commercially available tin dichloride, alkali metal alkoxides, and alkyl halide reagents.

[0108] Example 2. Synthesis of 2 - propyltris(tert - butyloxy)tin

[0109] This example describes a method for the one-pot direct synthesis of organotin trialkoxides. The method is based on the following reaction. The reaction is carried out by adding heat and a tetraalkyl(quaternary)ammonium salt as a catalyst.

[0110] KSn(OtBu) 3 + (CH 3 ) 2 CH 2 I → i PrSn(OtBu) 3

[0111] The product KSn(OtBu) 3 from Example 1, 0.67 molar equivalents (based on 1 molar equivalent of tin) of tetrabutylammonium iodide ((n-Bu) 4 N(I)) as a catalyst, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a solution with a concentration of approximately 0.10 g KSn(OtBu) 3 / ml of toluene. The solution was mixed at room temperature. Then, 1.5 molar equivalents of 2-iodopropane ((CH 3 ) 3 ) 2 CH 2 I) relative to the amount of KSn(OtBu) i was slowly added with stirring. Then, the reaction mixture was heated to 80 °C and stirred for 2 days. After that, the volatiles were removed under vacuum, and the remaining residue was filtered through a bed of diatomaceous earth using pentane. The filtrate was evacuated and distilled to give 2-propyltris(tert-butoxy)tin ( 3 ) Figure 4 as a transparent yellow liquid. i PrSn(OtBu) 3 is the 1 H NMR spectrum of the product, which shows the following chemical shifts: 1H NMR (400 MHz, neat) δ 1.95 (heptane, 1H), 1.56 (d, 6H), 1.48 (s, 27H) ppm. Figure 5 Shows the product i PrSn(OtBu) 3 of 119 Sn NMR spectrum, which shows a single peak: 119 Sn NMR (149 MHz, neat) δ -222 ppm). The single tin environment showed that in KSn(OtBu) 3 Towards i PrSn(OtBu) 3 No tin by-product was found in the conversion.

[0112] This example demonstrates a method for the direct synthesis of organotintrialkoxides with primary Sn-C bonds with high single organic radical specificity.

[0113] Example 3. Synthesis of 1 - propyltris(tert - butyloxy)tin

[0114] This example describes two methods for the one-pot direct synthesis of organotin trialkoxides using different alkyl halides (RX). The methods are based on the following reaction, where RX in method A is n PrI, and in method B is n PrBr. The reaction is carried out by adding heat and a tetraalkyl (quaternary) ammonium salt as a catalyst.

[0115] KSn(OtBu) 3 + RX → n PrSn(OtBu) 3

[0116] Method A. KSn(OtBu) from Example 1 3 The product, 0.5 molar equivalent (based on 1 molar equivalent of tin) of tetrabutylammonium iodide ((n-Bu) 4 N(I)) and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a concentration of about 0.10 g KSn(OtBu) 3 / ml toluene solution. The solution was mixed at room temperature. Then, relative to KSn(OtBu) 3 The amount is 1.3 molar equivalents of 1-iodopropane ( n PrI). The reaction mixture was then heated to 45°C and stirred for 1 day. Afterwards, the volatiles were removed under vacuum and the remaining residue was filtered through a celite bed using pentane. The filtrate was evacuated and distilled to give 1-propyltri(tert-butyloxy)tin (n PrSn(OtBu) 3 ) is a transparent yellow liquid. Figure 6 shows the product n PrSn(OtBu) 3 's 119 Sn NMR spectrum, which shows a singlet: 119 Sn NMR (149 MHz, neat) δ -197 ppm). The single tin environment indicates that no tin by-products are found in the conversion of KSn(OtBu) 3 To n PrSn(OtBu) 3 in the conversion.

[0117] Method B. Repeat the procedure of Method A with the following two differences: use 0.4 molar equivalent of tetrabutylammonium iodide as the catalyst and use 1.3 molar equivalents of 1-bromopropane ( 3 PrBr) as the alkyl halide reagent relative to the amount of KSn(OtBu) n . Distill the filtrate to obtain 1-propyltri(tert-butoxy)tin ( n PrSn(OtBu) 3 ), which is a transparent yellow liquid. Figure 7 shows the product n PrSn(OtBu) 3 's 119 Sn NMR spectrum, which shows a singlet: 119 Sn NMR (149 MHz, neat) δ -197 ppm). The single tin environment indicates that no tin by-products are found in the conversion of KSn(OtBu) 3 To n PrSn(OtBu) 3 in the conversion.

[0118] This example demonstrates that different halide groups can be used for the direct synthesis of organotin trialkoxides with high single organo group specificity.

[0119] Example 4. Synthesis of 1 - but - 3 - enyltris(tert - butyloxy)tin (MAL)

[0120] This example describes a method for the one-pot direct synthesis of unsaturated organotin trialkoxides. The method is based on the following reaction. The reaction is carried out by adding heat and a tetraalkyl(quaternary)ammonium salt as the catalyst.

[0121] KSn(OtBu) 3 + (CH 3 )(H)C=C(H)(CH 2 Cl), → (CH 3)(H)C=C(H)(CH 2 )Sn(OtBu) 3

[0122] The product KSn(OtBu) from Example 1 3 , 0.1 molar equivalent (based on 1 molar equivalent of tin) of tetrabutylammonium iodide ((n-Bu) 4 4N(I)) as a catalyst, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a solution with a concentration of approximately 0.10 g KSn(OtBu) 3 / ml of toluene. The solution was mixed at room temperature. Then, 1.2 molar equivalents of 1-chloro-2-butene ((CH 3 ) relative to the amount of KSn(OtBu) 3 )(H)C=C(H)(CH 2 Cl) (a mixture of cis and trans isomers, approximately in a ratio of 70:30) was slowly added with stirring. Then, the reaction mixture was heated to 45 °C and stirred for 3 days. After that, the volatiles were removed under vacuum, and the remaining residue was filtered through a bed of diatomaceous earth using pentane. The filtrate was evacuated and distilled to obtain the product (CH 3 )(H)C=C(H)(CH 2 )Sn(OtBu) 3 (1-buten-3-yltris(tert-butoxy)tin or MAL), as a mixture of cis and trans isomers. The product is a clear yellow liquid.

[0123] Figure 8 This is the 3 )(H)C=C(H)(CH 2 )Sn(OtBu) 3 of 1 H NMR spectrum, which shows the following chemical shifts: 1 HNMR (400 MHz, pure) δ 5.70 (m, 2H), 2.41 (cis) + 2.38 (trans) (m, 2H), 1.87(m, 3H), 1.48 (cis) + 1.49 (trans) (s, 27H) ppm. Figure 9 This is the 3 )(H)C=C(H)(CH 2 )Sn(OtBu) 3 of 119 Sn NMR spectrum, which shows the following chemical shifts: 119Sn NMR (149 MHz, neat) δ -225 (trans), -227 (cis) ppm. The results showed that the major isomeric species was the trans one, and the ratio of isomers in the MAL product retained the ratio of isomers in the 1-chloro-2-butene reagent. The results also showed that no tin by-products were found in the conversion of 3 to (CH 3 )(H)C=C(H)(CH 2 )Sn(OtBu) 3 .

[0124] This example demonstrated a method for the direct synthesis of unsaturated organotin trialkoxides with high mono-organo specificity. This example also demonstrated that the method proceeds with both cis and trans isomers of the olefin halide reagent.

[0125] Example 5. UV - based synthesis of 2,2,2 - trifluoroethyltris(tert - butyloxy)tin (TFE)

[0126] This example describes a method for the one-pot direct synthesis of fluorinated organotin trialkoxides under ultraviolet light. The method is based on the following reaction.

[0127]

[0128] Sn 2 (OtBu) 4 , 1.3 molar equivalents (based on 1 molar equivalent of the di-tin reactant) of 2,2,2-trifluoroiodoethane (CF 3 CH 2 I) and pentane were added to a reaction vessel under an inert atmosphere and mixed to form a solution with a concentration of approximately 0.33 g Sn 2 (OtBu) 4 / ml of pentane. The solution was mixed at room temperature. Then, the solution was irradiated with ultraviolet light (40W LED; 365 nm) overnight (approximately 15 hours). After that, the reaction mixture was filtered through a bed of diatomaceous earth, and the volatiles in the filtrate were removed under vacuum. The resulting filtrate was distilled to give the final product CF 3 CH 2 Sn(OtBu) 3 (2,2,2-trifluoroethyl tris(tert-butoxy)tin or TFE). The product was a clear yellow liquid.

[0129] Figure 10 is the 3 CH 2 Sn(OtBu) 3 H NMR spectrum of the product, which shows the following chemical shifts: 1 1 ​1H NMR (400 MHz, pure) δ 1.77 (m, 2H), 1.06 (s, 27H) ppm. Figure 11 is the product CF 3 CH 2 Sn(OtBu) 3 of 119 the Sn NMR spectrum, which shows a singlet: 119 Sn NMR (149 MHz, pure) δ -231 (q) ppm. Figure 12 is the product CF 3 CH 2 Sn(OtBu) 3 of 19 the F NMR spectrum, which shows the following chemical shifts: 19 F NMR (pure) δ -53 (m) ppm. The NMR results indicate that no tin by-products were found in the conversion of KSn(OtBu) 3 to CF 3 CH 2 Sn(OtBu) 3 There were no tin by-products found in the conversion to CFCHSn(OtBu).

[0130] This example demonstrates a photochemical method for the direct synthesis of fluorinated organotin trialkoxides with high mono-organo specificity.

[0131] Example 6. LED - based synthesis of 2,2,2 - trifluoroethyltris(tert - butyloxy)tin (TFE)

[0132] This example describes a photochemical method for the one-pot direct synthesis of fluorinated organotin trialkoxides under visible (LED) light. This method is based on the following reaction.

[0133]

[0134] Part 1: Violet and blue light studies

[0135] The product KSn(OtBu) from Example 1, 3 1.1 molar equivalents (based on 1 molar equivalent of tin) of 2,2,2-trifluoroiodoethane (CF 3 CH 2 I) and acetonitrile were added to a reaction vessel under an inert atmosphere and mixed to form a concentration of approximately 0.25 g KSn(OtBu) 3A solution of / ml of acetonitrile. The solution was mixed at room temperature. Then, while stirring, the solution was irradiated with visible light for 1 day. The visible light was provided by a 100 W LED and was either violet light (about 400 nm) or blue light (about 460 nm). The external temperature of the reaction vessel was kept below 30 °C using a fan. After that, the reaction solvent was removed under reduced pressure, and the remaining residue was filtered through a diatomaceous earth bed using pentane. The volatiles in the filtrate were removed under vacuum, and the resulting oil was distilled to obtain the final product CF 3 CH 2 Sn(OtBu) 3 (2,2,2-trifluoroethyl tris(tert-butoxy)tin or TFE). The product was a clear yellow liquid.

[0136] Figure 13 and 14 shows the NMR spectrum of the product prepared using violet light. The product prepared using blue light showed indistinguishable results. Figure 13 is the product CF 3 CH 2 Sn(OtBu) 3 of 1 H NMR spectrum, which shows the following chemical shifts: 1 H NMR (400 MHz, pure) δ 1.57 (s, 27H), 2.27 (q, 2 H) ppm. Figure 14 is the product CF 3 CH 2 Sn(OtBu) 3 of 119 Sn NMR spectrum, which shows the following chemical shifts: 119 Sn NMR (149 MHz, pure) δ -231 (q) ppm. The results indicate that no tin by-products were found in the conversion of KSn(OtBu) 3 to CF 3 CH 2 Sn(OtBu) 3 .

[0137] Part 2. Green light studies

[0138] A solution was prepared according to Part 1, except that the solution was provided in a sealed NMR tube (under an inert atmosphere) instead of a reaction vessel. The NMR tube was irradiated with a 100 W green LED (about 530 nm) for 3 hours. As Figure 15 shown, through 119 the disappearance of the KSn(O t Bu) 3 signal (δ -188 ppm) in Sn NMR to confirm the conversion to the product CF3 CH 2 Sn(OtBu) 3 Conversion of. (Note that the Sn peak in the reaction mixture is too broad to be observed). Further confirmation of the conversion to the product CF 3 CH 2 Sn(OtBu) 3 is 119 achieved by the presence of the CF 19 signal in the 3 F NMR. As shown in 2 Sn(OtBu) 3 , after one hour, both the reagent CF 3 CH 2 Sn(OtBu) 3 signal and the product CF Figure 16 signal can be seen, with the reagent signal being stronger. After three hours, the relative magnitudes of the reagent signal and the product signal are reversed, which is consistent with the progress of the reaction to completion. 3 CH 2 I signal and the product CF 3 CH 2 Sn(OtBu) 3 Another experiment was conducted to study the effect of LED light on the method. A solution of KSn(OtBu)

[0139] Part 3. Ambient light studies

[0140] was added to a reaction vessel under an inert atmosphere, along with 1.5 molar equivalents (based on 1 molar equivalent of tin) of CF 3 CH 3 CH 2 I and acetonitrile, and the mixture was stirred to form a solution with a concentration of approximately 0.33 g KSn(OtBu) 3 / ml of acetonitrile (Solution A). Another solution (Solution B) was also added in the same manner as Solution A, except that the amount of tetrabutylammonium iodide was 0.4 molar equivalents relative to KSn(OtBu) 3 . Solutions A and B were heated to 80 °C and stirred for 2 days. After that, NMR analysis was performed on each sample. The results showed that for each sample, CF 3 CH 2 Sn(OtBu) 3 was not formed, indicating that more photons than those provided by standard ambient light are required to form the fluorinated trialkoxy product. This research result is in contrast to the result shown in Example 2, where a non-fluorinated trialkoxy product was prepared using the same reagents and the same heating conditions as in Solution B.

[0141] This example demonstrates a photochemical method for the direct synthesis of fluorinated organotin trialkoxides with high single-organo group specificity and high yield. This example also demonstrates the effectiveness of this method for visible light of various wavelengths. This example further demonstrates that the reaction to form the fluorinated trialkoxy product is photochemically driven.

[0142] Example 7. Synthesis of butylditin hexakis(tert - butyloxy) (BDT)

[0143] This example describes a method for the direct synthesis of an organoditin trialkoxide represented by Formula 1. The method is based on the following reaction. The reaction is carried out by adding heat and a tetraalkyl(quaternary)ammonium salt as a catalyst, and the product is purified by sublimation.

[0144]

[0145] (Formula 1)

[0146] The product of Example 1, KSn(OtBu) 3 (2.1 molar equivalents), tetrabutylammonium iodide ((n-Bu) 4 N(I)) (0.21 molar equivalent) as a catalyst, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a solution with a concentration of approximately 0.5 mmol KSn(OtBu) 3 / ml of toluene. The solution was mixed at room temperature. Then, 1.0 molar equivalent of 1,4-diiodobutane (CH 2 I)CH 2 ) 2 CH 2 I, Ambeed) was slowly added with stirring. The reaction mixture was heated to 60 °C and stirred overnight (about 15 hours). After that, the volatiles were removed under vacuum, and the remaining residue was dissolved in pentane. Then the pentane mixture was filtered through a bed of diatomaceous earth. The filtrate was evacuated under reduced pressure to obtain a colorless solid. Then the colorless solid was stirred in acetonitrile (5 mL / g of solid) overnight under an inert atmosphere. After stirring, the solid was re-collected by filtration through a sintered glass filter with medium porosity, and the solid was washed with a minimum amount of acetonitrile. Then the collected solid was dissolved in acetonitrile (10 mL / g of solid) by heating at 50 °C, and then the heated solution was filtered through diatomaceous earth into a sealed flask, and then the sealed flask was cooled to -20 °C to form crystals over a 12-hour period. After removing the mother liquor by decantation and evaporation, the crystalline solid was sublimed under vacuum (60 mTorr) to obtain the product (C 4 H 8 Sn 2 (OtBu) 6 , colorless crystals of Formula 1).Figure 17 is product C 4 H 8 Sn 2 (OtBu) 6 of 1 1H NMR spectrum, which shows the following chemical shifts: 1 1H NMR (400 MHz, C 6 D 6 ) δ 1.75 (t, 4H), 1.25 (t, 4H), 1.45 (s, 54H, OtBu) ppm. Figure 18 is product C 4 H 8 Sn 2 (OtBu) 6 of 119 119Sn NMR spectrum, which shows a singlet: 119 119Sn NMR (149 MHz, C 6 D 6 ) δ -196 ppm. The NMR results indicate that no tin by-products were found in the conversion of KSn(OtBu) 3 to (C 4 H 8 Sn 2 (OtBu) 6 .

[0147] This example demonstrates a method for the direct synthesis of an organic ditin trialkoxide having the general formula L 3 Sn-R-SnL 3 . This example also demonstrates that sublimation can be effectively used to purify the ditin composition.

[0148] Example 8. Synthesis of 1,3,5 - tris-(methyltin tris(tert - butyloxy))benzene (MTT)

[0149] This example describes a method for the direct synthesis of an organic tritin trialkoxide represented by formula 2. The method is based on the following reaction. The reaction is carried out by adding heat and a tetraalkyl(quaternary)ammonium salt as a catalyst.

[0150] (Formula 2)

[0152] The product of KSn(OtBu) 3 from Example 1, 0.1 molar equivalent (based on 1 molar equivalent of tin) of tetrabutylammonium iodide ((n-Bu) 4 4N(I)) and toluene are added to a reaction vessel under an inert atmosphere and mixed to form a concentration of approximately 0.10 g KSn(OtBu) 3A solution of / ml of toluene. The solution was mixed at room temperature. Then, 1,3,5-tris-(bromomethyl)benzene (C 3 was slowly added with stirring in an amount of 0.3 molar equivalents relative to KSn(OtBu) 9 H 9 Br 3 ). Then, the reaction mixture was heated to 45 °C and stirred overnight (about 15 hours). Thereafter, the volatiles were removed under vacuum and the remaining residue was filtered through a bed of diatomaceous earth using pentane. The filtrate was evacuated and washed with MeCN to give a white solid.

[0153] Figure 19 is the 6 H 3 (CH 2 Sn(OtBu) 3 ) 3 H NMR spectrum of the product (C 1 which shows the following chemical shifts: 1 H NMR (400 MHz, C 6 D 6 ) δ 1.45 (s, 81H), 2.75 (s, 6H), 7.08 (s, 3H) ppm. Figure 20 is the 6 H 3 (CH 2 Sn(OtBu) 3 ) 3 Sn NMR spectrum of the product (C 119 which shows a singlet: 119 Sn NMR (149 MHz, C 6 D 6 ) δ -229 ppm. The results show that no tin by-products were found in the conversion of KSn(OtBu) 3 to (C 6 H 3 (CH 2 Sn(OtBu) 3 ) 3 .

[0154] This example demonstrates a method for the direct synthesis of organotrinuclear tin trialkoxides and shows that other organopolytin trialkoxides can be prepared analogously.

[0155] Example 9. UV - light - based synthesis of 3,3,3,4,4,4 - hexafluoroisobutyltris(tert - butyloxy)tin (HFB) Synthesis

[0156] This example describes a method for the one-pot direct synthesis of fluorinated organotin trialkoxides under ultraviolet light. The method is based on the following reaction.

[0157]

[0158] (Formula 3)

[0159] Mix Sn 2 (OtBu) 4 with pentane in a reaction vessel to form a solution with a concentration of approximately 0.33 g Sn 2 (OtBu) 4 / ml of pentane. Cool the mixture to -40 °C. Then, with stirring, add 1.3 molar equivalents (based on 1 molar equivalent of the distannyl reactant) of (CF 3 ) 2 CHCH 2 I to the reaction vessel. While maintaining the reaction temperature below -30 °C, irradiate the solution with ultraviolet light (40W LED; 365 nm) for about 12 hours with mixing. Then further dilute the reaction mixture in pentane (5 mL pentane / 1 mL mixture) to form a dilute crude mixture, and then keep the dilute crude mixture at -20 °C for 24 hours. Then filter the reaction mixture through a bed of diatomaceous earth, and remove the volatiles in the filtrate under vacuum. Distill the resulting filtrate to obtain the final product represented by Formula 3 (CF 3 ) 2 CHCH 2 Sn(OtBu) 3 (3,3,3,4,4,4 - hexafluoroisobutyltris(tert - butyloxy)tin or HFB). The product is a transparent yellow liquid.

[0160] Figure 21 is the 3 ) 2 CHCH 2 Sn(OtBu) 3 of 1 H NMR spectrum, which shows the following chemical shifts: 1 H NMR (400 MHz, C 6 D 6 ) δ 3.58 (m, 1H), 1.46 (d, 2H), 1.33 (2, 27H), 1.06 (s, 27H) ppm. Figure 22 is the 3 ) 2 CHCH 2 Sn(OtBu) 3 of 119 Sn NMR (149 MHz, C 6 D6 ) spectrum, which shows a main peak at δ -219.23, and this main peak corresponds to the product compound (CF 3 ) 2 CHCH 2 Sn(OtBu) 3 , and minor peaks at δ -372.81 and δ -87.33, and these minor peaks correspond to dialkyltin impurities and tetraalkoxytin impurities respectively. The high integral value of the product relative to the impurities indicates high-purity (CF 3 ) 2 CHCH 2 Sn(OtBu) 3 product. Figure 23 is the 3 ) 2 CHCH 2 Sn(OtBu) 3 of the 19 19F NMR spectrum, which shows a single sharp peak: 19 19F NMR (376 MHz, neat) δ -69.2 ppm. 19 The NMR results indicate a single fluorine environment.

[0161] This example demonstrates a photochemical method for the direct synthesis of polyfluorinated organotin trialkoxides, and this method has high single-organo specificity.

[0162] Example 10. UV - light - based synthesis of 4,5,5,5,6,6,6 - heptafluoropentyltris(tert - butyloxy)tin (HFP) Synthesis

[0163] This example describes a method for the one-pot direct synthesis of fluorinated organotin trialkoxides under ultraviolet light. This method is based on the following reaction.

[0164]

[0165] (Equation 4)

[0166] Except that the reaction is carried out using (CF 3 ) 2 CF(CH 2 ) 2 I instead of (CF 3 ) 2 CHCH 2 I. According to the method of Example 9. The resulting filtrate is distilled to obtain the final product (CF 3 ) 2 CF(CH 2 ) 2 Sn(OtBu) 3(4,5,5,5,6,6,6-heptafluoropentyltri(t-butoxy)tin or HFP).

[0167] This example describes a photochemical method for the direct synthesis of polyfluorinated organotin trialkoxides with the desired high mono-organo specificity.

[0168] The above embodiments are intended to be illustrative and not restrictive. Additional embodiments are within the scope of the claims. Additionally, although the invention has been described with reference to specific embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. Any incorporation by reference of the above documents is limited such that no contrary subject matter to the express disclosure herein is incorporated. Where specific structures, compositions, and / or processes are described herein in terms of components, elements, ingredients, or other divisions, it is understood that unless otherwise expressly specified, the disclosure herein encompasses specific embodiments, embodiments that include the specific components, elements, ingredients, other divisions, or combinations thereof, and embodiments that consist essentially of such specific components, ingredients, or other divisions, or combinations thereof, which may include additional features that do not change the basic nature of the subject matter, as indicated in the discussion. The use of the term "about" herein refers to the expected uncertainty in the relevant values, as would be understood by a person of ordinary skill in the art in a particular context.

Claims

1. A method for synthesizing a mono-organotin trialkoxide, the method comprising: React MSn(OR') 3 with RX n to form R[Sn(OR') 3 n , where M is Li, Na, K, Rb or Cs; X is Cl, Br or I; n≥1, R is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond; and R' is an organic group having 1 to 10 carbon atoms, where the organic group may optionally contain heteroatoms and / or unsaturated bonds.​ 2. The method according to claim 1, wherein n = 1.

3. The method according to claim 2, wherein R contains one or more fluorine atoms.

4. The method according to claim 2 or claim 3, wherein R includes a C=C group.

5. The method according to claim 1, wherein n = 2.

6. The method according to claim 5, wherein R contains 3 to 12 carbon atoms.

7. The method according to claim 5 or claim 6, wherein R includes an unsaturated group.

8. The method according to claim 1, wherein n = 3.

9. The method according to claim 8, wherein R includes an aromatic group.

10. The method according to any one of claims 1 to 9, wherein X is Br or I, and M is K.

11. The method according to any one of claims 1 to 10, wherein the reaction is carried out for less than about 2 days.

12. The method according to any one of claims 1 to 11, wherein the reaction is carried out at a temperature of about -20°C to about 100°C.

13. The method according to any one of claims 1 to 12, wherein the reaction is carried out using a quaternary ammonium catalyst and / or a phosphonium catalyst.

14. The method according to claim 13, wherein the catalyst is tetrabutylammonium halide.

15. The method according to claim 14, wherein the halogen is I.

16. The method according to any one of claims 1 to 15, wherein the reaction is carried out under a directional visible or ultraviolet light source.

17. The method according to claim 16, wherein the light source is monochromatic.

18. The method according to any one of claims 1 to 17, the method further comprising purifying the R[Sn(OR') 3 n product by distillation.​ 19. The method according to any one of claims 1 to 18, the method further comprising purifying the R[Sn(OR’) 3 n product by sublimation.​ 20. The method according to any one of claims 1 to 19, wherein the MSn(OR') 3 is formed by reacting SnX' 2 with MOR', where X' is Cl, Br or I, and MSn(OR') 3 is used without separation to react with RX n react.

21. The method according to any one of claims 1 to 20, wherein the carbon bonded to Sn is a primary carbon (only one C-C bond) or a secondary carbon (two C-C bonds).

22. A method for synthesizing a mono-organotin trialkoxide, the method comprising: React Sn 2 (OR') 4 with RX under ultraviolet light to form RSn(OR') 3 , where X is Cl, Br or I; R is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond; and R' is an organic group having 1 to 10 carbon atoms, where the organic group may optionally contain heteroatoms and / or unsaturated bonds.

23. The method according to claim 22, wherein R contains a fluorine atom.

24. The method according to claim 22, wherein R comprises -CF 3 group.

25. The method according to any one of claims 22 to 24, wherein the wavelength of the ultraviolet light is about 315 nm to about 400 nm.

26. The method according to any one of claims 22 to 25, wherein R' is methyl, ethyl, propyl, isopropyl, tert-butyl, isobutyl or tert-pentyl.

27. The method according to any one of claims 22 to 26, the method further comprising filtering the reaction product to remove Sn 2 X 2 (OR') 2 Precipitating by-products.

28. The method according to any one of claims 22 to 27, wherein the reaction is carried out at a temperature of about -20°C to about 80°C.

29. An organometallic compound represented by the formula ((R'O) 3 Sn) n -R, where n ≥ 3, R' is an organic group having 1 to 10 carbon atoms, and R is an organic group having 5 to 31 carbon atoms and forms a C-Sn bond with each Sn atom.

30. The organometallic compound according to claim 29, wherein n is 3.

31. The organometallic compound according to claim 29 or claim 30, wherein R contains one or more fluorine atoms.

32. The organometallic compound according to any one of claims 29 to 31, wherein R contains an unsaturated group.

33. The organometallic compound according to any one of claims 29 to 31, wherein R includes an aromatic group.

34. The organometallic compound according to any one of claims 29 to 33, wherein R' is methyl, ethyl, propyl, isopropyl, tert-butyl, isobutyl or tert-pentyl.

35. The organometallic compound according to claim 29, wherein the compound comprises 1,3,5-tris-(methyltin tris(tert-butoxy))benzene.

36. A solution comprising an organic solvent and the organometallic compound according to any one of claims 29 to 35.

37. The solution according to claim 36, wherein the organic solvent comprises an alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, an ester, an ether, a ketone or a combination thereof, and wherein the concentration of the solution based on the tin concentration is about 0.0025 M to about 1.4 M.

38. The solution according to claim 36, wherein the organic solvent comprises a primary alcohol.

39. The solution according to claim 36, wherein the organic solvent comprises an aromatic solvent.

40. The solution according to any one of claims 36 to 39, said solution further comprising a second organometallic composition represented by the formula R a SnL 3 and different from the organometallic compound, wherein L is a hydrolyzable ligand and R a is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond.

41. A structure comprising a film capable of radiation patterning and a substrate, wherein the film comprises the organometallic compound according to any one of claims 29 to 35 and / or a hydrolysis product of the organometallic compound according to any one of claims 29 to 35.

42. A structure comprising a film capable of radiation patterning and a substrate, wherein the film is formed of the compound according to any one of claims 29 to 35 and comprises Sn-C bonds.

43. The structure according to claim 42, wherein the film further comprises Sn-O-Sn bonds and Sn-OH bonds.

44. A method for forming a fluorinated organometallic compound represented by the formula (CF 3 )RSn(OR') 3 , wherein R is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond; and R' is an organic group having 1 to 10 carbon atoms, the method Comprising: React (CF 3 )RX with Sn 2 (OR') 4 or MSn(OR') 3 under visible or ultraviolet light, where X is Cl, Br or I.

45. The method according to claim 44, wherein the method comprises reacting (CF 3 )RX with Sn 2 (OR') 4 under ultraviolet light.

46. The method according to claim 44, wherein the method comprises reacting (CF 3 )RX with MSn(OR') 3 under visible light.

47. The method according to any one of claims 44 to 46, wherein X is I.

48. The method according to any one of claims 44 to 46, wherein X is Br.

49. The method according to any one of claims 44 to 48, wherein R is CH 2 group.

50. The method according to any one of claims 44 to 48, wherein R is CR 1 R 2 group, wherein R 1 and / or R 2 is a halogenated organic group having 1 to 5 carbon atoms.

51. The method according to any one of claims 44 to 48, wherein R comprises a C=C group.

52. The method according to any one of claims 44 to 51, wherein R' is methyl, ethyl, propyl, isopropyl, tert-butyl, isobutyl or tert-pentyl.

53. The method according to any one of claims 44 to 52, wherein the visible light is monochromatic.

54. The method according to any one of claims 44 to 53, wherein the visible light comprises violet light, blue light or green light.

55. The method according to any one of claims 44 to 54, wherein the wavelength of the ultraviolet light is about 315 nm to about 400 nm.

56. The method according to any one of claims 44 to 55, wherein the visible light or ultraviolet light is provided by an LED.

57. The method according to any one of claims 44 to 56, wherein the reaction is carried out for less than about 2 days.

58. The method according to any one of claims 44 to 57, wherein the reaction is carried out at a temperature of about -20 °C to about 80 °C.

59. A fluorinated organometallic compound represented by the formula (CF 3 ) 2 R 1 C-R 0 Sn(OR') 3 , wherein R 0 is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond; R 1 is hydrogen, a halogen atom or an organic group having 1 to 10 carbon atoms; and R' is an organic group having 1 to 10 carbon atoms.

60. The fluorinated organometallic compound according to claim 59, wherein R 1 is F.

61. The fluorinated organic metal compound according to claim 59, wherein R 1 comprises -CF 3 groups.

62. The fluorinated organometallic compound according to claim 59, wherein R 1 is hydrogen.

63. The fluorinated organometallic compound according to any one of claims 59 to 62, wherein R' is methyl, ethyl, propyl, isopropyl, tert-butyl, isobutyl or tert-pentyl.

64. The fluorinated organometallic compound according to any one of claims 59 to 63, wherein R 0 is (CH 2 ) n , and wherein n is from 1 to 4.

65. A solution comprising an organic solvent and a fluorinated organometallic compound according to any one of claims 59 to 64.

66. The solution according to claim 65, wherein the organic solvent comprises an alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, an ester, an ether, a ketone, or a combination thereof, and wherein the concentration of the solution based on the tin concentration meter is from about 0.0025 M to about 1.4 M.

67. The solution according to claim 65, wherein the organic solvent comprises a primary alcohol.

68. The solution according to any one of claims 65 to 67, said solution further comprising a second organometallic composition represented by the formula R a SnL 3 and different from the fluorinated organometallic compound, wherein L is a hydrolyzable ligand and R a is an organic group having 1 to 31 carbon atoms and forming a C-Sn bond.

69. A structure comprising a film capable of radiation patterning and a substrate, wherein the film comprises the fluorinated organometallic compound according to claim D and / or a hydrolysis product of the fluorinated organometallic compound according to any one of claims 65 to 67.

70. A structure comprising a film capable of radiation patterning and a substrate, wherein the film is formed of the compound according to any one of claims 65 to 67 and contains Sn-C bonds.

71. The structure according to claim 70, wherein the film further contains Sn-O-Sn bonds and Sn-OH bonds.

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