Organic tin compositions having ligands containing acetal functionality, patterning compositions having organic tin blends, and positive tone patterning

Abstract

The organic-based tin patterning composition has a radiation-sensitive ligand having an acetal functional group. The precursor composition is a composition comprising (OR4) (OR3) R2CR1SnL3, where the R group is a substituted or unsubstituted hydrocarbyl group, and L is a hydrolysable ligand. The precursor may be formed as a coating, which may be patterned using radiation, in particular EUV radiation. Coatings formed using blended precursors with hydrocarbyl ligands in which some have acetal groups and other are free of acetal groups may be particularly effective for improving positive tone patterning.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to co-pending U.S. Provisional Patent Application 63 / 535,003, filed August 28, 2023, entitled “Organotin Compositions Having Ligands Containing Acetal Functional Groups”, which is incorporated herein by reference. Technical Field

[0003] This invention relates to organotin compounds containing ligands having acetal functional groups and typically bonded to C-Sn bonds. The invention also relates to radiation-patternable compositions and corresponding coatings, said compositions and coatings having blends of organotin compositions wherein a portion of the tin atoms have ligands containing acetal groups. Positive hue patterning with desired properties can be achieved using said organotin blends. Background Technology

[0004] Organometallic compounds suitable for radiation-based patterning can provide metal ions in solution or vapor form for thin film deposition. Organotin compounds can provide high EUV absorption and radiation-sensitive tin-ligand bonds that can be used for photolithographic patterning of thin films. Fabricating increasingly smaller semiconductor devices using EUV radiation requires novel materials with wide process ranges to achieve the desired patterning resolution and low defect density.

[0005] Patterning compositions are typically referred to as resists or photoresists because they can be used for pattern transfer. Resists can be called negative tone resists, in which the exposed material is retained during physical pattern formation; or positive tone resists, in which the unexposed material is retained during physical pattern formation. Depending on the desired pattern shape, there can be advantages in selecting the resist tone for processing. Summary of the Invention

[0006] The problem to be solved: To obtain MOR resists with high process stability, tin-carbon bond chemistry with high activation energy is crucial. However, doing so may compromise photochemical sensitivity. Therefore, a ligand approach with high stability and high sensitivity is required.

[0007] Solution: Novel RSn ligands containing acetal functional groups enable a new exposure mechanism for RSn resists driven by photochemistry on the R group (rather than the radiative decomposition of the R-Sn bond), thus opening up potential photoresist design space.

[0008] In one aspect, the present invention relates to the formula L3SnR 1 R 2 C(OR 3 (OR) 4 ) represents an organotin compound with an acetal functional group, wherein R 3 and R 4 R is independently a substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 1 It is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond, and L is a hydrolyzable ligand.

[0009] In another aspect, the present invention relates to the formula L3SnR 1 R 2 C(O2R 3 ) represents an organotin compound with an acetal functional group, wherein R 3 R is a hydrocarbon group having 1 to 6 carbon atoms. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 1 It is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond, and L is a hydrolyzable ligand.

[0010] In one related aspect, the present invention relates to a method comprising (OR) 4 (OR) 3 )R 2 CR 1 The composition of SnL3, wherein R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 It is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, wherein R 3 and R 4 Independently a substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, or wherein R3 and R4 together form a bridging structure -OR 5 O- (R 5 = R 3 + R 4 ), where R 5 The acetal is a hydrocarbon group having 1 to 10 carbon atoms and forming a cyclic linkage between the O atoms, and L is a hydrolyzable ligand. A precursor solution may be contained in the composition in an organic solvent.

[0011] In another aspect, the present invention relates to a blend composition comprising two or more organotin compositions, wherein at least one organotin composition has an acetal functional group. One composition may be as described in the preceding paragraph, while the other composition is of formula (R a SnL'3 represents, or a combination thereof, where R a L is a substituted or unsubstituted hydrocarbon ligand having 1 to 30 carbon atoms and a Sn-C bond, and L' is a hydrolyzable ligand that is the same as or different from L.

[0012] In another aspect, the present invention relates to a coated substrate comprising a substrate and an organotin coating on the surface of the substrate, wherein the organotin coating comprises an oxo-hydroxo network, the oxo-hydroxo network being incorporated with a formula (OR) 4 (OR) 3 )R 2 CR 1 Sn represents the organotin group, where R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently substituted or unsubstituted hydrocarbon groups having 1 to 4 carbon atoms, or together forming a bridging structure -OR 5 O- (R 5 = R 3 + R 4 ), where R 5 It consists of a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal.

[0013] In some aspects, the present invention relates to a precursor solution for depositing patterned compositions, said precursor solution comprising:

[0014] Organic solvents,

[0015] By formula (OR) 4 (OR) 3 )R 2 CR 1 SnL3 represents the first tin precursor composition, wherein R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR5 O- (R 5 = R 3 +R 4 ), where R 5 It is a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, and L is a hydrolyzable ligand, and

[0016] From formula R a SnL'3 represents the second tin precursor composition, R a It is a substituted or unsubstituted hydrocarbon ligand having 1 to 30 carbon atoms, and L' is a hydrolyzable ligand that is the same as or different from L.

[0017] In another aspect, the present invention relates to a method for patterning a coated substrate having a virtual image formed using patterned EUV radiation, the coated substrate comprising a substrate and an organotin coating on the surface of the substrate, the organotin coating comprising unirradiated portions and irradiated portions.

[0018] The unirradiated portion comprises a patternable composition comprising an oxo-hydroxyl network, the oxo-hydroxyl network being bound to a group of elements of the formula (OR) 4 (OR) 3 )R 2 CR 1 Sn represents the organotin group, where R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR 5 O- (R 5 = R 3 + R 4 ), where R 5 The method comprises a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, the method comprising:

[0019] The coating on the surface of the substrate is brought into contact with an aqueous liquid to substantially remove the irradiated portion while leaving the unirradiated portion substantially intact.

[0020] In other aspects, the present invention relates to a method for patterning a coated substrate having a virtual image formed using patterned EUV radiation, the coated substrate comprising a substrate and an organotin coating on the surface of the substrate, the organotin coating comprising unirradiated portions and irradiated portions.

[0021] The unirradiated portion comprises a patternable composition comprising an oxo-hydroxyl network, the oxo-hydroxyl network being bound to a group of elements of the formula (OR) 4 (OR) 3 )R 2 CR 1 Sn represents the organotin group, where R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR 5 O- (R 5 = R 3 + R 4 ), where R 5 The method comprises a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, the method comprising:

[0022] The coating on the surface of the substrate is brought into contact with an organic liquid to substantially remove the unirradiated portion while keeping the irradiated portion substantially intact.

[0023] Furthermore, the present invention relates to a method for synthesizing substituted 1,3-benzodioxole compounds, the method comprising:

[0024] The reaction of catechol in an organic solvent with hexamethylsilazine forms an intermediate; and

[0025] The intermediate in an organic solvent is reacted with a ketone or aldehyde in the presence of a trimethylsilyltrifluoromethanesulfonate catalyst to form a substituted 1,3-benzodioxane.

[0026] Furthermore, the present invention relates to a method using formula C6R a R b R c R d O2CR 1 R 2 The compound represented is a halogen-substituted compound having optionally additional substitutions of 2-alkyl-1,3-benzodioxane, wherein R 1 R is a hydrocarbon group with 1 to 15 carbon atoms, either substituted or unsubstituted. 2It is a hydrocarbon group consisting of hydrogen or substituted or unsubstituted hydrocarbons having 1 to 10 carbon atoms. Attached Figure Description

[0027] Figure 1 This is a schematic diagram illustrating various possible reactions of an organotin composition having an acetal functional group, triggered by energy absorption from radiation.

[0028] Figure 2A It is shown Figure 1 A schematic diagram of the formation of dimer products from hypothetical free radical intermediates.

[0029] Figure 2B It is shown Figure 1 A schematic diagram illustrating the reaction of a hypothetical free radical intermediate with an organotin composition having olefin functional groups to form a polymer product.

[0030] Figure 3 This is a graph showing the normalized FTIR peak area as a function of baking temperature for three organotin compositions with acetal functional groups and two organotin compositions without acetal functional groups.

[0031] Figure 4 It is a contrast curve of the coated wafer, which is prepared by photoresist solution containing acetal functional groups (curves A and B) or photoresist solution without acetal functional groups (curve CE1), and then exposed and baked at 100°C (PEB).

[0032] Figure 5 It is a contrast curve of the coated wafer, which is prepared by photoresist solution containing acetal functional groups (curves A and B) or photoresist solution without acetal functional groups (curve CE1), and then PEB is performed at 120°C.

[0033] Figure 6 It is a contrast curve of the coated wafer, which is prepared by photoresist solution containing fluorinated ligands and acetal functional groups (curve C) or photoresist solution containing fluorinated ligands but without acetal functional groups (curve CE2), and then subjected to PEB at 100°C.

[0034] Figure 7 These are a set of contrast curves for coated wafers prepared from a resist solution containing acetal functional groups and then subjected to different exposure and baking temperatures: 100°C or 140°C.

[0035] Figure 8 These are a set of contrast profiles for coated wafers prepared from a resist solution containing acetal functional groups and then subjected to different hard-bake conditions: 100°C, 150°C, 200°C, or no hard-bake.

[0036] Figure 9 It is a CD-SEM image of a contact hole pattern formed by EUV irradiation of a photoresist coating prepared from a resist solution containing acetal functional groups. Detailed Implementation

[0037] Novel organotin photoresist compositions incorporating organic ligands with acetal functional groups have been synthesized. These novel compositions can effectively provide complementary properties to precursor blends to enhance the available process window, particularly in terms of irradiation dose and contrast for positive tone patterning. Some organotin embodiments are also available in blends for negative tone patterning. The composition also provides enhanced thermal stability to the blended precursor compositions and allows the positive tone process window to open with dose. As demonstrated herein, some embodiments of organotin precursors with acetal ligands exhibit good solubility in a wide variety of solvents, both aqueous and organic. As a result of this broad solubility, acetal ligand tin precursors enable novel blend compositions with improved positive tone patterning capabilities. The aromatic forms of the acetal ligands are derivatives of 1,3-benzodioxane, and although these compounds have more limited solubility, these precursors can be used in blends to introduce a variety of properties into the blends, such as film solubility, contact angle modulation, ion generation, and intermolecular chemistry. The applicant has developed highly efficient organotin patternable compositions for patterning at very high resolutions. Organotin precursor blends comprising components of acetal-liganded tin compositions can particularly effectively improve patterning, and the blends described herein can be effective in terms of processability for positive tone patterning and in improving the patterning results of positive tone patterning. For suitable embodiments, the high solubility of tin compounds with acetal ligands in aqueous developers can reduce the radiation dose required to make the blend film soluble, and the high ligand stability can extend the solubility of the blend film to high radiation doses, thereby improving positive tone processing capability. In other words, blend film compositions containing acetal ligands enable a wider positive tone patterning window by improving the solubility of the irradiated material over a wider range of radiation doses.

[0038] As further described below, the first step in the use of these organotin compounds involves the synthesis of the compound. The synthesized compound or blend can be used in solution or vapor deposition methods to form an organotin oxide hydroxide film capable of radiation patterning. For the formation of the constituent blend, the deposition method can be adjusted accordingly to achieve the desired composition of the constituent components in the final deposited material. Deposition is typically achieved by the hydrolysis of organotin compounds having hydrolyzable ligands, which are hydrolyzed during processing to form a coating composition comprising oxo and hydroxyl ligands and intact organotin moieties. In the respective coating, the oxo and hydroxyl ligands form a network for the coating composition. The degree of condensation of the oxo-hydroxyl network can be controlled by treatments (e.g., heating, blanket irradiation, or environmental conditions) to help guide image processing. The solid-state reactions occurring in the coating can be somewhat complex, and the complexity can be even greater for reactants, such as those provided by specific ligands. Nevertheless, a basic understanding of the overall reaction can be obtained from the data to understand the controls used to guide patterning improvements.

[0039] As demonstrated below, suitable embodiments of organotin compositions with acetal functional groups exhibit good solubility over a wide range of solvents and good ligand thermal stability. The broad solubility in aqueous liquids makes the compositions unsuitable for use alone in positive-tone development in alkaline (e.g., tetramethylammonium hydroxide) aqueous solutions, and the high thermal and radiation stability of the Sn-R bonds in acetal ligand compositions generally results in poor contrast for negative-tone patterning. Nevertheless, organotin compositions with acetal ligands have been found to be significantly useful in photoresist composition blends for positive-tone patterning by extending the EUV dosing process window. Some of the compositions (especially aromatic derivatives) can also be used for negative-tone patterning. Regarding positive-tone patterning, the extended dosing process window can be useful for obtaining sharper images after development and for providing process flexibility. According to the currently accepted IUPAC terminology, "acetal" is used to refer to the conventionally named acetal HR. 1 C(OR 3 (OR) 4 ) and ketal R 1 R 2 C(OR 3 (OR) 4 Therefore, according to current IUPAC usage, unless otherwise specified, "acetal" should be considered to include both conventional acetals and ketals. In some embodiments, R 3 and R 4 Groups are bridged R 5The groups are substituted to form a cyclic methylenedioxy moiety. According to accepted nomenclature, the aromatic embodiments described are derivatives of 1,3-benzodioxane, but they retain the methylenedioxy moiety.

[0040] Typically, acetal groups can be reactive in suitable environments. Evaluation of the performance of coatings formed using organotin compositions with acetal groups indicates that some reactions can occur, but no reaction products have been elucidated to date. Organotin compositions with radiation-sensitive acetal functional groups can undergo intramolecular and intermolecular reactions in response to radiation exposure and / or heat treatment, and thus such reactions can lead to improved sensitivity. Acetal-containing organic ligands can decompose upon absorbing radiation, forming unstable intermediate reactants that can further undergo intramolecular reactions, enabling subsequent Sn-C bond cleavage and ligand loss. Novel ligands with acetal functional groups provide novel organotin photoresist designs based on intra-R group changes induced by radiation decomposition rather than Sn-C bond cleavage induced by radiation decomposition.

[0041] Compared to conventional organic-based tin photoresists, organic-based tin photoresist compositions containing acetal functional groups also exhibit improved thermal stability. Conventional organic-based tin photoresists typically function by breaking Sn-C bonds through radiation decomposition, in which the material undergoes a transformation from a hydrophobic, carbon-rich material to a hydrophilic, carbon-deficient material. Development can then be performed using a suitable development process, resulting in positive or negative tone patterning. Acetal-containing ligands introduce new functionality into resist design.

[0042] In the following results, compositions containing tin acetal ligands exhibited fairly good thermal stability, as tested by measuring the change in CH vibration with baking temperature. These results indicate relatively low radiation sensitivity. Therefore, when used in precursor blends, the blended resists were found to maintain good solubility in positive tin developer even at very high radiation doses. The blended compositions can be modified to include a nonpolar, highly radiation-sensitive organotin moiety that undergoes significant dealkylation (i.e., Sn-C bond cleavage) in response to radiation or heating, thereby improving the polarity of the film and its solubility in aqueous developer, while substantially retaining the acetal ligand at high radiation doses. This acetal ligand inhibits complete condensation of the oxo-network, thus allowing continued solubility in aqueous solvents. Nevertheless, hard baking at the end of radiation patterning can complete the consolidation of the composition left after patterning.

[0043] As used herein, and generally conforming to usage in the art, the terms “organotin,” “alkyltin,” and “alkyltin” are used interchangeably, and similarly, “monoalkyl” is used interchangeably with “monoorgano” or “monoalkyl.” An “alkyl” (i.e., “organo”) ligand indicates a bond to tin via a Sn-C bond, where the carbon atom is typically sp. 3 or sp 2 Hybridized, and forming bonds that are generally not hydrolyzable by contact with water. The "alkyl" group may optionally have internally unsaturated bonds not involving bonding with tin, and heteroatoms, i.e., different from carbon and hydrogen. Chemical groups bonded to metal atoms are generally referred to in the art as ligands. The term "hydrolyzable ligand" generally refers to a ligand bonded to Sn with hydrolyzable bonds, such as an alkoxy ligand (e.g., -OR') bonded to an oxygen atom with an organic substituent on the oxygen atom, or an amino compound ligand (e.g., -NR) bonded to one or more organic substituents on the nitrogen atom with an organic substituent on the nitrogen atom. 1 R 2 The synthetic method described herein produces monoalkyltin trialkoxides (also known as monoalkyltin trialkoxys) in high yields and with low levels of contaminants, including (non-tin) metals and polyalkyltins (i.e., polyalkyl groups, such as dialkyltin and trialkyltin). This organometallic precursor synthesis approach is well-suited for efficient scaling up for commercial production, and in some embodiments, the reactions can be carried out in a single-pot synthesis.

[0044] Organic tin 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" (hereinafter referred to as the '684 patent), 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" (hereinafter referred to as the '153 patent) 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. Generally, monoalkyltin patterning compositions can be used for negative tone or positive tone patterning. Nevertheless, specific ligand structures have been developed to improve specific patterning processes, such as for improved negative tone patterning. In the case of blends, some of the organotin compositions described herein can be particularly effective for forming positive tone resist compositions.

[0045] The compositions synthesized herein can be effective precursors for forming alkyltin oxo-hydroxy compositions that are conducive to 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 monoalkyltin oxo-hydroxy patterning compositions, which can be represented by the formula RSnO (1.5-(x / 2)) (OH) x where 0 < x ≤ 3. Hydrolysis can be conveniently carried out to form the oxo-hydroxy composition in situ, such as during deposition and / or after the initial coating formation. In other words, the RSn moiety is embedded in the oxo-hydroxy network, and for blends, the various RSn moieties are considered to be distributed in a common oxo-hydroxy network. Although, for example, alkyltin triaminides (or alkyltin triamines) and alkyltin trialkynides (or alkyltin trialkynes) described in the above-mentioned '618 patent can be used under hydrolysis conditions to form radiation-sensitive coatings for patterning, it can be desirable to use alkyltin trialkoxides as part of a solution-based film-forming composition. The direct synthesis of alkyltin trialkoxides having ligands with acetal functional groups, as well as other suitable synthetic methods, are described herein.

[0046] Mono-organic (monoalkyl) tin precursor compositions can typically be represented by the formula RSnL3, where R is an organic group (i.e., a ligand) and L is a hydrolyzable ligand. For processes that form radiation-patternable coatings, L is typically hydrolyzed (e.g., in situ) before, during, or shortly after deposition, yielding a coating on a substrate containing a polymeric organic tin oxo-hydroxylated composition, where the Sn-R bonds remain substantially intact. As a result, radiation-patternable coatings with radiation-sensitive Sn-R bonds can be achieved. Once hydrolysis is complete on the substrate surface, the composition can be considered a monolithic material, with tin atoms distributed within an oxo-hydroxylated network connecting the material. To form radiation-patternable coatings from blends of different mono-organic tin compositions, similar oxo-hydroxylated networks are achieved, where tin atoms with different R groups are distributed throughout the oxo-hydroxylated network to form a monolithic material. In this case, the recombination free energy and other collective effects may influence individual reactivity. While solution-based reactivity can provide guidance for composition behavior, reactivity in the coating may differ slightly due to altered environments.

[0047] Acetal ligands

[0048] As shown in Formula 1 below, acetal ligand compositions can typically be derived from formula L3SnR. 1 R 2 C(OR 3 (OR) 4 ) indicates that R 3 and R 4 Independently, it is a hydrocarbon group having 1 to 4 carbon atoms, R 2 R is hydrogen (traditional acetal) or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms (traditional ketal). 1 The ligand is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond, and L is a hydrolyzable ligand. Equation (1) shows another representation of this structure.

[0049] .

[0050] Other acetal ligand compositions are shown in Formula 2 below, and can generally be derived from Formula L3SnR 1 R 2 C(O2R 5 ) indicates that R 5 R is a hydrocarbon group having 1 to 10 carbon atoms and forming a cyclic bond between the O atoms of the acetal (which is referred to in the art as the methylenedioxy functional group), 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 1The substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond, and L is a hydrolyzable ligand. Formula (2) provides another representation of the cyclic methylenedioxy structure. As used herein, the methylenedioxy structure is considered an acetal structure, even if it is aromatic.

[0051] .

[0052] Comparing equation (1) and equation (2), R 5 R is a bridging group 3 and R 4 The combination of these elements forms the resulting cyclic diether. In a sense, R 5 R represents a bridge structure 3 and R 4 A combination of . In some implementations, R 5 It may include aromatic groups, and some embodiments of aromatic substances are illustrated by example.

[0053] For acetal ligand tin compounds in formula (1) or formula (2), R 1 The hydrocarbon group having 1 to 15 carbon atoms, 1 to 10 carbon atoms in other embodiments, 1 to 5 carbon atoms in some embodiments, 1 to 4 carbon atoms in other embodiments, and 2 or 3 carbon atoms and having a Sn-C bond in exemplary embodiments. 2 The hydrocarbon group is hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, 1 to 5 carbon atoms in other embodiments, and 1 to 3 carbon atoms in still other embodiments, and is hydrogen or -CH3 in exemplary embodiments. In some embodiments, R 2 It may include unsaturated hydrocarbon groups. Those skilled in the art will recognize that additional ranges of carbon atoms within the explicitly defined scope above are considered and are within the scope of this disclosure.

[0054] If R 5 Including the benzene ring, the resulting structure is a 2-alkyl group (R) of 1,3-benzodioxane pentadiene. 2 (It is hydrogen) or a 2,2-dialkyl derivative, as shown in the following formula:

[0055]

[0056] In order to be synthesized into the composition as a tin ligand, R 1This includes halides, such as chloride groups. Additionally, benzyl halogenation can be ideal for patterning purposes. For example, because iodine has good EUV absorption, including an iodine group can improve the absorption of the resist. Since fluorine groups can also facilitate patterning, fluorine (-F) or trifluoromethyl (-CF3) groups can be ideal substituents on the benzyl group. A more general formula for 1,3-benzodioxane ligands is:

[0057] ,

[0058] It allows the specification of substituents on aromatic rings.

[0059] Typically, the breaking of the Sn-C bond in organotin compounds RSnL3 can be modulated by the organic ligand R bound to Sn. While other factors may affect the stability of the R-Sn bond, its stability generally depends on the substitution of the α-carbon (i.e., the carbon directly bonded to the Sn atom). Generally, the stability of the Sn-C bond decreases with increasing α-carbon substitution, e.g., primary carbon > secondary carbon > tertiary carbon. As the stability of the Sn-C bond increases, the dosage required to break the bond also increases. Therefore, conventional organotin resists typically need to contain R ligands with secondary or tertiary α-carbons to reduce the dosage required for patterning. However, organotin compositions containing ligands with secondary and tertiary α-carbons generally tend to be more thermally unstable, which can negatively impact purity, stability, and film processing.

[0060] The ligands with acetal functional groups described herein typically include an R group having a primary α-carbon, which can enhance the thermal stability of organotin resist compositions. For such compounds, R in the above formula... 1 It can be written as -CH2R', where R' is a chemical bond or has 1 to 14 carbon atoms. Furthermore, novel organotin compositions with acetal functional groups can undergo changes within the R group induced by radiolysis, thereby generating radical intermediates located on the R group. These radical intermediates can then undergo various chemical reactions to form the desired product, which can be targeted based on the appropriate selection and / or design of the intact ligand structure, photolithographic processing conditions, and the presence of other components within the organotin photoresist matrix. Possible pathways are... Figure 1 As shown in the image.

[0061] In some embodiments, ligands containing fluorinated or iodinated functional groups are desirable. In particular, because iodine has relatively high EUV absorption, the inclusion of iodine atoms can improve the radiation absorption of the composition. Examples of ligands containing iodinated aromatic groups are given below. Fluorinated ligands are also desirable. Fluorinated functional groups can improve radiation absorption, may provide for the generation of fluoride ions, and can improve thermal stability. Examples of fluorinated and iodinated functional groups are given. Halogenated groups (typically chlorides, bromides, or iodides) are also used in synthetic routes to form tin-carbon bonds.

[0062] In some embodiments, the ligand may also include an unsaturated alkenyl group. The alkenyl group can provide some enhanced radiation absorption and can provide cross-linking reactions to stabilize the ligand structure, which can be ideal for positive hue patterning. Specifically, an alkenyl group may be included, for example, in the R group of the ligand. 2 The group may include an alkenyl group. An example is given below. Co-pending U.S. Patent 18 / 731,702, entitled “Organo-based tin alkoxides as precursors of patterned compositions having fluorine substituents and carbon-carbon double bonds” by Jilik et al., further describes an organo-based tin patterned composition having both fluorine and alkenyl groups.

[0063] The chemistry of organotin acetal ligand compositions can be predicted by the structure of the ligands containing acetal functional groups. It is important to note that the reaction pathway in the coating may differ from the expected solution-phase reaction. The presence of acetal functional groups within the R ligand enables novel chemical pathways for photolithographic patterning by targeting chemical changes and / or reactions within and / or between components in the photoresist matrix. Results show that chemical changes can occur, but the nature of these changes has not yet been confirmed or characterized. Instead of relying solely on contrast generated by Sn-C cleavage, the new chemical pathway allows for novel material design considerations to achieve high-contrast organotin photoresist patterning. The use of precursor blends allows for further utilization of these properties due to internal differences in precursor performance. As the following results show, precursor blends can extend the process window with variations in dosage between the lower and / or upper dosage limits.

[0064] While not wishing to be limited by theory, irradiation or heating of the acetal ligand composition can lead to the formation of a free radical intermediate. In some embodiments, the free radical intermediate can undergo free radical polymerization to form a cross-linked organotin film. For example, as... Figure 2A As shown, two or more adjacent free radical intermediates can react to form a polymer product, which is shown as a dimer. In some embodiments, the free radical intermediate can act as a polymerization initiator in a matrix containing other components having olefinic functional groups. For example, as... Figure 2BAs shown, the photoresist substrate can contain blends of different organotin compositions, wherein one of the compositions contains an acetal functional group and the other contains an olefin functional group, and can undergo free radical polymerization to obtain a polymerized organotin film.

[0065] In some embodiments, the ligand having an acetal functional group may also include a leaving group near the acetal carbon (i.e., the C atom bonded to two O atoms) so that the radical intermediate can react further to generate a product having an activated olefin functional group.

[0066] In some implementations, the radical intermediate can undergo intramolecular rearrangement to form an unstable Sn-C bond, which can spontaneously lead to Sn-C cleavage and loss of R ligands. Radiation-induced chemistry of the acetal functional group can provide an indirect nonradiative mechanism for Sn-C cleavage, thus improving the cleavage efficiency of acetal R-groups with primary α-carbons. By incorporating photosensitive acetal functional groups onto the ligands, the ligands can decompose into reactive substances upon irradiation, which can cyclize at the α-carbon, ultimately leading to the loss of total ligands.

[0067] Specific acetal ligand and precursor blends

[0068] Typically, for positive tone patterning, irradiation of the resist is required to remove the resist coating. Films formed from acetal tin compounds have been found to be more widely soluble in aqueous liquids, thus providing improved positive tone resist compositions where solubility in alkaline aqueous solutions after exposure to radiation is generally suitable. While coating compositions formed using these precursors alone may not serve as positive tone resists due to their high post-deposition solubility in alkaline aqueous solutions, blended coating compositions can be insoluble in developer aqueous solutions without irradiation and provide improved positive tone patterning compared to coating compositions without acetal ligands. Typically, irradiation of organic-based tin photoresist materials makes them more hydrophilic, thus improving their solubility in developer aqueous solutions. With further increases in irradiation dose, the irradiated material undergoes significant consolidation and densification, resulting in the formation of insoluble tin oxides. In this instance, this transition to insolubility at higher doses is referred to as the condensation cliff. The use of blended organic-based tin photoresist compositions containing acetal ligands can mitigate condensation cliff formation and promote the solubility of materials irradiated at high doses in developer aqueous solutions. In some exemplary embodiments, condensation cliffs were not observed within the studied dose range. To increase the size of the process window, it is necessary to push the condensation cliff to higher doses while maintaining approximately the initial dose required to achieve solubility or extending it to lower doses. To make this process adjustment, the ratio of precursor compounds in the blend and the characteristics of the precursor compounds can be selected accordingly.

[0069] Therefore, acetal ligands can be particularly useful in blended organic-based tin photoresist compositions used for positive tone processing. Positive tone processing refers to a photolithography process in which the photoresist material becomes soluble in a developer after exposure to radiation. As described herein and in conjunction with the '684 and '153 patents, with the use of suitable ligands, organic-based tin photoresists can function as either negative-tone or positive-tone photoresists, depending on the developer used. Typically, the initially deposited organic-based tin film suitable for positive tone patterning is insoluble in aqueous developer solutions due to the hydrophobicity of the organic ligands bound to Sn within the film. Exposing the film to radiation causes the bonds between the organic ligands and Sn atoms to break, thus allowing the formation of hydrophilic Sn-OH bonds at their sites. Consequently, the unexposed coating is hydrophobic, while the exposed coating is hydrophilic, and the contrast between these two regions allows for the selective removal of either region based on the developer used. For example, organic solvents typically remove the unexposed areas, while aqueous solvents typically remove the exposed areas. However, with increasing dose and / or higher post-exposure baking (PEB) temperature, the exposed area further condenses, and solubility in the developer generally decreases. For negative toning processing, organotin resists at low doses are hydrophobic and generally soluble in organic developers until a sufficiently high dose is given, causing the organic ligands to decompose and thus increasing hydrophilicity, making the exposed material insoluble in the organic developer. The general material properties are similar to those in positive toning processing, where exposure to radiation makes the hydrophobic organotin film more hydrophilic. At low doses, the material is hydrophobic and generally insoluble in aqueous developer solutions. As the dose increases and more organic ligands decompose through radiation, the polarity (hydrophilicity) of the material increases, making the exposed material soluble in aqueous developer solutions. At sufficiently high doses, the material further condenses, and solubility decreases. The dose range within which organotin photoresist films can dissolve in positive toning developers (such as aqueous alkaline solutions) can be referred to as the positive toning process window. In other words, the positive hue process window is the dose range within which positive hue behavior is observed before the condensation cliff (i.e., extended condensation and densification) occurs, which renders the material insoluble at high doses and / or process temperatures. Typically, a photoresist system needs to be designed to maximize this positive hue process window.

[0070] As described above, the acetal ligands described herein can be used in blends of organotin compositions to improve the polarity and hydrophilicity of photoresist films, and thereby improve the positive tinting process window. Typically, it is ideal that positive tin-based photoresists are hydrophobic and insoluble at low doses after deposition. Similarly, it is ideal that the condensation cliff requires the highest possible dose so that the positive tinting process window (i.e., the dose at which the organotin photoresist is soluble in developer aqueous solutions) can be widened. By including acetal ligands in organotin photoresist blends, the hydrophilicity of the photoresist can be altered to improve solubility in developer aqueous solutions. Individual components of the organotin blend (e.g., individual organotin precursors with different R ligands) can be selected such that the overall blend is sufficiently hydrophobic at low doses to be insoluble in alkaline aqueous solutions, while also possessing sufficient resistance to extended condensation at high doses to maintain solubility. As found in exemplary embodiments, relatively low proportions of acetal ligands can effectively extend the condensation cliff to high doses.

[0071] The positive-tone organotin blends described herein comprise: a mixture of organotin precursors containing an R group having an acetal functional group and an organotin precursor having a hydrophobic R group. Positive-tone organotin blends can typically be derived from formula R... ac SnL3 and RSnL'3 represent a mixture of organotin compounds, wherein R ac The ligand is a ketal, and R is a substituted or unsubstituted, saturated or unsaturated, straight-chain, branched, cyclic or aromatic hydrocarbon group having 1 to 30 carbon atoms. Suitable examples of the R group may include methyl, ethyl, vinyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, butenyl, cyclopentyl, cyclohexyl, phenyl, benzyl, adamantyl, their respective isomers, heteroatom-substituted products, and combinations thereof. In some embodiments, R... ac Ligands can include fluorinated or iodinated substances. Organotin blends can independently contain a variety of ligands of different types (acetal and non-acetal).

[0072] The blended precursors can be characterized by the fraction of acetal and non-acetal precursors. After deposition, the hydrolyzed coating contains a corresponding proportion of organic ligands. The acetal and non-acetal precursors can be independent single substances or blends of multiple substances, such that the final blend can contain 2, 3, 4, 5, or more than 5 organotin substances, but must have at least one acetal and one non-acetal substance, wherein each substance is characterized in the RSn portion, i.e., each substance has a different R in the RSn portion. For vapor deposition, although compounds can theoretically be mixed, due to differences in vapor pressure or boiling point, it is generally easier to control vapor deposition by using compounds delivered separately (simultaneously and / or sequentially), and then combining these compounds into the final deposited material. In the precursor solution, the various organotin compounds and substances exist as a homogeneous mixture, and precise interactions in solution are generally not significant. The complex equilibrium in solution is thought to form through hydrolysis, solvent decomposition, and condensation pathways, and may lead to the distribution of organotin compounds with an overall distribution of various RSn compounds corresponding to the initial ratios of the different organotin precursors provided. Similarly, once the organotin composition is deposited as a coating, the various RSn compounds are thought to be substantially randomly distributed in the resulting organotin oxo-hydroxyl network.

[0073] Regarding proportions, precursor blends typically contain a range of acetal tin precursors, ranging from any of the lower limits of about 2 mol%, or about 3 mol%, or about 4 mol%, or about 5 mol%, to the upper limits of about 40 mol%, or about 50 mol%, or about 60 mol%, or about 70 mol%, relative to the total moles of tin in the blend. Typically, the remaining portion of the organotin component is a non-acetal tin precursor used to obtain 100% organotin precursor. Specifically, precursor blends may contain a range of non-acetal tin precursors, ranging from any of the lower limits of about 30 mol%, about 40 mol%, about 50 mol%, or about 60 mol%, to the upper limits of about 95 mol%, 96 mol%, 97 mol%, or 98 mol%. Those skilled in the art will recognize that further ranges of acetal tin (in) precursors and non-acetal tin precursors are considered and are within the scope of this disclosure.

[0074] The selection of specific blends can be based on the thermal and radiation responses of the specific compounds. For the improved positive tint resists described herein, it may be ideal for the acetal material to maintain the solubility of the blend composition in the positive tint developer up to high radiation doses. Simultaneously, it is ideal for the blend composition to have almost no solubility in the positive tint developer until a relatively low threshold dose is given. Therefore, for such positive tint blends, it is ideal to contain one or more non-acetal ligands that initially render the total blend insoluble in aqueous developer solutions, but which can undergo ligand cleavage at relatively low doses to produce soluble substances. Generally, it is ideal for the unirradiated material to have relatively good thermal stability to avoid contrast loss during PAB or PEB processes, where heating is required to promote solvent removal, radiation-induced pyrolysis, latent image condensation, etc. With these objectives in mind, the blend can balance the characteristics of the various components. For positive tone patterning, non-acetal hydrocarbon ligands are desirable because they provide a large, nonpolar organic group that initially makes the blend insoluble in aqueous developer solutions while also exhibiting high radiolytic efficiency (i.e., a weaker Sn-R bond, e.g., an R ligand with a secondary or tertiary α-carbon). Additionally, it is desirable to improve radiation absorption to enhance radiolytic degradation without correspondingly reducing thermal stability. These moieties can provide significant improvements to positive tone development in terms of the ability of acetal groups to form reactive substances that maintain good solubility in positive tone developers while inhibiting complete condensation into tin oxides (which leads to loss of solubility).

[0075] In summary, for some embodiments, positive-tone organotin resist compositions can combine polar, large-size, and radiodegradable ligands (acetal ligands) with nonpolar, large-size, and radiodegradable ligands (non-acetal ligands). Specific non-acetal ligands of interest include, for example, cyclopentylmethyltin (exemplary compound P3), phenyl-isopropyl (exemplary compound P1), and tert-butyltin to provide better positive-tone patterning performance. The expected advantages of these precursor blends with respect to positive-tone patterning are at least in the following three aspects:

[0076] 1. Large R groups prevent the formation of dense oxide structures and push the "condensation cliff" to very high doses. Positive tint resists will be ideally completely soluble at all doses above a certain threshold dose (i.e., the dose-to-clear dose).

[0077] 2. The large-sized non-acetal ligands in the blend impart significant hydrophobicity to the deposited film, thus leading to the insolubility of the deposition material (such as TMAH) in the positive-tone resist. High radiosensitivity allows this ligand to undergo primarily selective decomposition during irradiation, producing more polar substances (SnR → Sn-OH) at relatively low doses. The presence of the large Sn-acetal ligands or their reaction products remaining in the coating prevents these polar substances from undergoing extensive condensation. Therefore, exposure can drive the formation of polar (more water-soluble) exposure regions.

[0078] 3. To achieve good positive tonal patterning, the developer aqueous solution should wet the entire surface to dissolve the irradiated portion. One consequence of the hydrophobicity of the ligand structure and unirradiated areas is poor film wettability, which can make it difficult to ensure that the developer can physically cover, coat, and flow across the surface of the resist composition. Incorporating some acetal ligand moiety improves the polarity of the coating sufficiently to improve developer wetting without imparting complete film solubility. The patterning material can then possess sufficient polarity for the developer to spread uniformly on the wafer surface. Therefore, precursor blends containing acetal ligands can provide a practical improvement in the delivery of developer aqueous solutions. These practical improvements can be very significant for commercial resist products that should produce the expected results.

[0079] One advantage of organotin compositions containing ligands with acetal functional groups is that these ligands enable novel organotin photoresist compositions with high thermal stability. As mentioned above, conventional organotin photoresists rely on the radiolysis of Sn-C bonds to drive the polarity difference between the exposed and unexposed materials, which can then be extracted into a physical pattern during development. To improve the radiolysis sensitivity of Sn-C bonds, ligands with more substituted α-carbons can be used (e.g., R = isopropyl, sec-butyl, tert-butyl, cyclopentylmethyl, phenyl-isopropyl, etc.). However, increasing α-carbon substitution generally reduces the thermal stability of Sn-C bonds, and a trade-off between thermal stability and radiosensitivity is typically observed. The thermal stability of organotin photoresists is important because it is crucial to localize the breaking of Sn-C bonds within the irradiated area of ​​the film. Low thermal stability can lead to undesirable Sn-C breakage in unirradiated areas during conventional photolithography processes, such as pre-development baking steps (e.g., post-coat baking (PAB) or post-exposure baking (PEB)). The acetal functionalized compositions described herein mitigate this trade-off by allowing for higher radiosensitivity without a corresponding reduction in thermal stability. Therefore, R groups with more thermally stable primary α-carbon and acetal functional groups can be used.

[0080] Synthesis of acetal ligands

[0081] For precursor synthesis, individual precursors can be synthesized using efficient synthetic schemes tailored to specific organo-based ligands, and these individual precursors can be blended if desired. The applicant has developed a variety of synthetic schemes for a wide range of ligands used in organo-tin precursors, which are generally efficient and effective in terms of cost, time, or other practical factors. Regarding versatile and efficient processes for a range of organo-based ligands, synthetic schemes based on tin oxide oxidation starting from Sn(II) alkoxides have been discovered, and these methods offer high selectivity and efficiency. One of these approaches directly involves the synthesis of hydrolyzable ligands of the amino group (-NR'2) or alkynyl group (-CCR'), which can be converted into alkoxy ligands. A second approach can be used for the direct synthesis of organo-tin compounds as trialkoxides. This second approach is illustrated by example.

[0082] Organotin compositions containing ligands with acetal functional groups can be synthesized via a tin oxide reaction pathway. A first of this type of approach has previously been described in U.S. Patent Application No. 2022 / 0064192 (incorporated herein by reference), entitled “Method for preparing organotin compositions using convenient ligands providing reactants” by Edson et al. A typical tin oxide reaction can be described as a multi-step reaction, wherein the first step involves reacting a Sn(II) compound (e.g., SnCl2, SnBr2, etc.) with a metal (alkali metal, alkaline earth metal, and / or pseudo-alkaline metal) compound to form a mixed metal intermediate. The mixed metal intermediate is then reacted with an alkyl halide to form the organotin product RSnL3, where R is a substituted or unsubstituted hydrocarbon group with a Sn-C bond, and L is a suitable hydrolyzable ligand, such as an amino group (-NR'2) or an alkynyl group (-CCR'). In general, the reaction can be represented by the following reaction:

[0083]

[0084] In some embodiments, the hydrolyzable ligand L can be converted to an alkoxy group. This reaction can be represented by the following reaction:

[0085]

[0086] A similar reaction scheme is described in U.S. Patent Application 2022 / 0242889 (incorporated herein by reference), entitled “Method for the Preparation of Organotin Compounds” by Ermert et al.

[0087] In the second tin oxide method, monoalkyltin trialkyloxides are directly synthesized without the need for exchanging hydrolyzable ligands. This synthetic method is described in detail in U.S. Patent Application 2024 / 0199658 (hereinafter referred to as '658 application) entitled "Direct Synthesis of Organo-based Tin Alkoxides" by Jelik et al. (which is incorporated herein by reference). Specifically, and as described herein and in the following examples, monoalkyltin trialkyloxide compounds having an acetal functional group in the R group can be synthesized via the following overall reaction:

[0088]

[0089] M is typically an alkali metal, such as Li, K, Na, Cs, or Rb. R' is typically a substituted or unsubstituted hydrocarbon group having ≤10 carbon atoms, and OR' is generally selected based on the desired properties of the product monoalkyltin trialkyloxide RSn(OR')3, such as stability, melting point, solubility, and ease of purification. In some embodiments, OR' is tert-butoxy (OtBu). In some embodiments, OR' is tert-pentoxy (OtAm). '658 application describes an alternative route based directly on Sn(OR')2, bypassing the bimetallic intermediate; however, this alternative route produces tin byproducts, making it generally less desirable, although it is available for certain ligands.

[0090] The alkali metal tin trialkyl oxide intermediate MSn(OR')3 (i.e., a Sn(II) bimetallic alkoxide) has been found to be a useful reagent for forming organo-tin trialkyl oxides, and can be prepared according to the following reaction:

[0091]

[0092] Unlike the dimetallic composition mentioned in formula (3), metallic tin trialkyl oxides can be separated and purified, although this step is not required for the synthesis of organotin trialkyl oxides.

[0093] RX compounds are selected to provide the desired alkyl ligand R for the organotin product. The wide availability of RX compounds as reactants and their general reactivity in the corresponding reactions provide the ability to introduce a broad range of alkyl ligands (e.g., alkyl ligands with acetal functional groups) into the monoalkyltin product. For the reactions described herein, primary and secondary R groups (i.e., R groups having 1° or 2° C atoms forming C-Sn bonds) are particularly effective in forming the desired RSn(OR')3 composition. X can generally be a halogen selected from I, Br, or Cl.

[0094] The alkali metal tin alkoxide intermediate MSn(OR')3 (i.e., a Sn(II) bimetallic alkoxide) has been found to be a useful reagent for forming organotin trialkyloxides, and can be prepared according to the following reaction:

[0095]

[0096] 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 isolated, purified, and used as a solid reagent in synthesis, and its preparation is described in detail in application '658. When reacted with an alkyl halide under suitable temperature and conditions, an oxidative addition reaction can occur, in which an alkyltin bond is formed, and an alkali metal halide is rapidly formed, thereby forming RSn(OR')3. The alkali metal halide salt can alternatively be filtered off, and / or the RSn(OR')3 product can be purified and collected by distillation.

[0097] Reactions are typically carried out in dry organic solvents under an oxygen-free or oxygen-deficient atmosphere (e.g., nitrogen-purged or argon-purged atmosphere). Solvents can be chosen to suit the solubility of the various components for a particular reaction. Due to the interaction between the solvent and metal ions, the choice of solvent can be based at least in part on the reaction rate in the chosen solvent, which can be evaluated empirically. If different solvents are chosen, they are generally miscible. Aprotic polar solvents are generally available, such as ethers (e.g., dimethyl ether, diethyl ether), tetrahydrofuran (THF), acetone, and mixtures thereof. For alkylation steps in which alkyl groups are bonded to tin, nonpolar solvents are also found to be effective, such as alkanes (e.g., hexane, pentane) and toluene. Solvents 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 respect to each other.

[0098] Catalysts containing halides can be present during the reaction of bimetallic MSn(OR')3 compounds and hydrocarbon halide RX compounds. Catalysts typically include quaternary ammonium salts such as tetrabutylammonium iodide, tetrabutylammonium bromide, and / or tetrabutylammonium hexafluorophosphate, and / or tetraphenylphosphonium chloride. While the exact role of these catalysts is not fully understood, they are known to act as phase-transfer catalysts by facilitating the dissolution of inorganic compounds in organic solvents. Other phase-transfer catalysts, based on their shared chemical properties, should similarly be available in this case, regardless of whether this function is directly utilized. Reactions using MSn(OR')3 as a starting material can generally be carried out in a single-pot process without any intermediate steps (such as separation, purification, transfer, etc.), but purification of the final product is usually required.

[0099] The reactions described herein are highly selective for the formation of monoalkyltin trialkyloxide compounds, and the alkyl halide can typically be present as a reactant in a molar excess of the MSn(OR')3 composition. In some embodiments, the alkyl halide may be present in an amount of up to about 2 molar equivalents relative to the MSn(OR')3 compound, in other embodiments in an amount of up to about 1.6 molar equivalents relative to the MSn(OR')3 compound, in other embodiments in an amount of up to about 1.3 molar equivalents relative to the MSn(OR')3 compound, and in yet another embodiment in an amount of up to about 1.1 molar equivalents relative to the MSn(OR')3 compound. In some embodiments, the alkyl halide and the MSn(OR')3 compound may be present in approximately stoichiometric amounts.

[0100] In some embodiments, the reaction is typically carried out at temperatures below about 100°C, in other embodiments below about 80°C, and in still other embodiments below about 60°C. In some embodiments, the reaction is carried out at room temperature. In some embodiments, the reaction is carried out under ultraviolet light irradiation. In embodiments where visible light and / or ultraviolet light irradiation is applied during the reaction, the reaction may or may not be heated. In some embodiments, ultraviolet light irradiation is carried out at a wavelength of 365 nm. In some embodiments, ultraviolet light irradiation is carried out at a wavelength of 254 nm. The reaction is typically stirred during the duration of the reaction. It can be achieved by... 1 H and / or 119 Sn NMR analysis of the reaction mixture is used to monitor the effect of the reaction to determine when the reaction has reached full completion, such as greater than about 90% yield. In some embodiments, the reaction may proceed for no more than about 5 days, in other embodiments for no more than about 3 days, in still other embodiments for no more than about 1 day, and in yet another embodiment for no more than about 1 hour to about 4 days. Those skilled in the art will recognize that other ranges of time and temperature within the clearly defined ranges above are considered and are within the scope of this disclosure. Reaction time and temperature can generally depend on the properties of the alkyl halide (RX). The reactivity of alkyl halides generally follows the following order: I > Br > Cl in the order of X, and 1° > 2° >> 3° in the order of carbons forming the CX bond. Suitable reaction time and temperature can be determined by conventional experiments.

[0101] The above discussion focuses on the synthesis of organotin compounds (such as organotin trialkyloxides) with hydrolyzable ligands. These reactions involve providing suitable reactants to provide organic ligands for bonding with tin. For acetal-containing ligands, the reactants have the structure RX, where R includes an acetal group. In particular, specific synthetic routes have been developed for aromatic compounds containing the benzodioxone structure.

[0102] To attach RX (where X is a halogen) to the above acetal ligand structure, R = R 1 R 2 C(OR 3 (OR) 4 ) or R 1 R 2 C(-OR 5 O-). Halogen (usually chlorine, but bromine or iodine can also be used) binds to R at the same site where the ligand will eventually bind to tin. 1 Bonding. If the carbon bonded to tin is a primary carbon, then chlorine or other halogens are located in R. 1 On the terminal carbon, and if tin combines with secondary carbon, then chlorine or other halogens react with R. 1 The halogen is bonded to the methylene or substituted methylene carbon. Similarly, to bond tin to a tertiary carbon, chlorine or other halogens are bonded to branched carbons. Since R is usually required to be bonded to a primary carbon for thermal stability, the halogen to be substituted is usually required to be located at R. 1 The end, as used in the examples.

[0103] Typically, acetals and dioxacyclopentanes are well-studied and generally available, and the desired chlorinated forms are available or can be synthesized as needed to advance the synthesis of organotin compositions. Several synthetic techniques have been developed to facilitate the formation of specific derivatives for the synthesis of desired benzodioxacyclopentadiene compounds for the corresponding ligands, as described above. 5The synthesis involves forming a dimethoxybenzene having any desired functional group on the benzene ring. Exemplary forms include monofluoro, diiodo, and di(trifluoromethyl) derivatives on the benzene ring. Derivatized benzenes are generally well known, and the derivatives are generally compatible with the remaining synthetic steps. Next, the methoxy group is converted to a hydroxyl group by hydrolysis with a demethylating agent (such as boron tribromide) and water. The resulting dihydroxy product is first reacted with hexamethyldisilazane (HN(SiMe3)2, HMDS) in an amount calculated to or slightly greater than the stoichiometric amount. This reaction is carried out under heating conditions in toluene or another suitable organic solvent. Once the reaction is complete, the reaction solution is cooled, and volatile compounds are removed by evaporation for maintenance. Dichloromethane or another suitable organic solvent is added to the intermediate, along with approximately one equivalent of aldehyde chloride (ClR). 1 COH) or ketones (ClR) 1 COR 2 ) is added to the reaction solution, where R 1 and R 2 The corresponding groups in the formula correspond to those in the benzodioxane ligand described above. A catalyst (trimethylsilyl trifluoromethanesulfonate) is then slowly added to activate the aldehyde or ketone and drive the reaction to form benzodioxane. The reaction can continue until complete, which may require overnight. Volatile substances can be removed, and the solid product can be purified by recrystallization. The purified product can then be dissolved using the above process and reacted to form an organotin compound.

[0104] Once the product is formed, the organotin trialkylene oxide can be purified. Purification depends on the nature of the product, but generally involves separating the desired product from byproducts and any unreacted reagents that may be present. Purification can typically be achieved by methods known in the art. Typical purification techniques may include filtration, recrystallization, extraction, distillation, combinations thereof, etc. Crude product mixtures are generally filtered to remove insoluble contaminants and / or byproducts, such as metal halide salts like KI, from the solution containing the desired product. Recrystallization can be used to purify solid compounds by heating to form a saturated solution and then cooling it. Extraction techniques may include, for example, liquid-liquid extraction, where the desired compound is separated based on the relative solubility of the desired compound using two immiscible solvents of different densities. Purification may also involve removing any volatile compounds (including solvents) from the product mixture by drying or exposure to vacuum. For products with significant vapor pressures (which is often the case for tin trialkylene oxide), purification of the product by vacuum distillation or, if desired, fractionation designed to achieve high purity may be ideal. See Clark et al.'s published U.S. Patent Application 2020 / 0241413, entitled "Monoalkyltin trialkyloxides and / or monoalkyltin triamine compounds with low metal and / or particulate contamination and corresponding methods," which is incorporated herein by reference. These purification techniques can be used to obtain pure products with very low levels of non-tin metals and multi-organotin contaminants (each tin atom having more than one C-Sn bond).

[0105] Coatings, depositions and related compositions:

[0106] The organotin precursor compositions described herein are effective for radiation patterning, particularly EUV patterning. The ability to offer greater flexibility in ligand selection allows for further improvements in patterning results and the design of ligands to be particularly effective for specific applications. In particular, appropriately selected precursors can effectively improve the quality of positive hue patterning. 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 edge coating, and printing such as inkjet printing and screen printing. As discussed in the above-cited '618 patent, many precursors are also suitable for vapor deposition onto the substrate. For certain R ligand compositions and / or specific process considerations, vapor deposition can be used to prepare radiation-sensitive coatings, which can be adapted to blended ligands by sequential or simultaneous deposition. Vapor deposition is typically performed using pure, solvent-free precursor preparations.

[0107] For solution deposition, 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, like 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-butanol, methanol, isopropanol, 1-propanol), ketones (e.g., methyl ethyl ketone), mixtures thereof, etc. Typically, the choice of organic solvent may be influenced by solubility parameters, volatility, flammability, toxicity, viscosity, and potential chemical interactions with other processing materials. After the components of the solution are dissolved and combined, the properties of the substance may be altered due to localized in-situ hydrolysis, hydration, and / or condensation.

[0108] An organo-based tin precursor can be dissolved in a solvent at a concentration that provides a suitable Sn concentration for forming a coating with a suitable processing thickness. The concentration of the substance 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 appropriate coating parameters, lower overall concentrations can produce desirable solution properties. It is suitable to use thinner coatings to achieve ultra-fine patterning and reduce material costs. Typically, the concentration is selected to suit the chosen coating method. The coating properties are further described below. Typically, tin concentrations range from about 0.005 M to about 1.4 M, in another embodiment from about 0.02 M to about 1.2 M, and in yet another embodiment from about 0.035 M to about 1.0 M. Those skilled in the art will recognize that other tin concentration ranges within the clearly defined ranges above are considered and are within the scope of this disclosure.

[0109] It has been found that controlling the water content can yield a consistent and stable precursor solution. Specifically, the water content can be adjusted, typically by adding a small amount of water to the solvent to achieve a target water content, which generally does not exceed about 10,000 ppm by weight, in another embodiment about 100 ppm to about 2,500 ppm by weight, and in yet another embodiment about 200 ppm to about 1,500 ppm by weight. Those skilled in the art will recognize that additional ranges beyond the explicit scope described above are considered and are within the scope of this disclosure. The use of water content adjustment is further discussed in U.S. Patent 11,300,876 (hereinafter referred to as '876 Patent) entitled "Stable Solutions of Monoalkyltin Alkoxides and Their Hydrolysis and Condensation Products" (incorporated herein by reference).

[0110] In some embodiments, the improved photosensitive precursor composition may be present in a blend solution having one or more other organotin compositions typically represented by the formula RSnL3 and their hydrolysis products, wherein R is selected from various portions described in detail herein and explicitly set forth above. Such blend solutions can be tailored to optimize various performance considerations, such as solution stability, coating uniformity, and patterning properties. In some embodiments, the improved photosensitive composition may contain at least 1 mol% of the desired component Sn in the blend solution, in other embodiments at least 10 mol% of Sn in the blend solution, in other embodiments at least 20 mol% of Sn in the blend solution, and in other embodiments at least 50 mol% of the specific desired component Sn in the blend solution. Other mol% ranges for the improved photosensitive composition within the defined range of the blend solution are considered and are within the scope of this disclosure.

[0111] Due to their high vapor pressure, the organotin compositions described herein can generally be used as precursors for forming coatings via vapor deposition. Vapor deposition methods typically include chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), and modifications thereof. In a typical vapor deposition process, the organotin composition can react with small molecule vapor phase reagents (such as H2O, O2, H2O2, O3, CH3OH, HCOOH, CH3COOH, etc.), which serve as O and H sources for preparing radiation-sensitive organotin oxide and oxide hydroxide coatings. Vapor deposition of radiation-patternable organotin coatings has been described in the above-cited '618 patent and in PCT application PCT / US2019 / 031618 entitled "Method for Preparing EUV Patternable Hard Masks" by Wu et al. (which is incorporated herein by reference). The preparation of radiation-sensitive organotin coatings can generally be achieved by reacting the volatile organotin precursor RSnL3 with small vapor phase molecules. The reaction may include the hydrolysis / condensation of organotin precursors to hydrolyze the hydrolyzable ligands while leaving the Sn-C bond largely intact.

[0112] An overview of representative radiation-based patterning methods (such as extreme ultraviolet (EUV) lithography) involves depositing or coating a photoresist material onto a substrate as a thin film, baking before exposure (or after coating), exposing to the radiation pattern to create a latent image, baking after exposure, and then developing to convert the radiation-patterned virtual image into a physical pattern. For negative-tone patterning using liquids, typically organic solvents, unexposed material is removed to produce a developed photoresist pattern. Negative-tone patterning can also be performed using reactive gases or other drying methods. For positive-tone patterning, a liquid, typically an aqueous liquid, is brought into contact with the radiation-patterned virtual image to remove exposed material, thereby forming a physical pattern. Fewer steps can be used if desired, and additional steps can be used to remove residues to improve pattern fidelity.

[0113] The thickness of the coating capable of radiation patterning can depend on the desired process. For use in single-patterning EUV lithography, a coating thickness is typically chosen to produce patterns with low defect rates and pattern reproducibility. In some embodiments, suitable coating thicknesses can be from 1 nm to 100 nm, in other embodiments from about 1.5 nm to 50 nm, and in still other embodiments from about 2 nm to 25 nm. Those skilled in the art will understand that other ranges of coating thickness are considered and are within the scope of this disclosure.

[0114] The coating thickness of a radiation-patternable coating prepared by vapor deposition can typically be controlled by appropriately selecting the reaction time or the cycle length of the process. The thickness of the radiation-patternable coating can depend on the desired process. For use in single-pattern EUV lithography, the coating thickness is typically selected to produce patterns with low defect rates and pattern reproducibility. In some embodiments, suitable coating thicknesses can be from 1 nm to 100 nm, in other embodiments from about 1.5 nm to 50 nm, and in still other embodiments from about 2 nm to 25 nm. Those skilled in the art will understand that other coating thickness ranges are considered and are within the scope of this disclosure.

[0115] The substrate typically provides a surface on which coating materials can be deposited, and can comprise multiple layers, with the surface associated with the topmost layer. There are no particular limitations on the substrate, and it can contain any reasonable material, such as silicon, silica, other inorganic materials like ceramics, and polymeric materials.

[0116] Following the deposition and formation of a radiation-patternable coating, further processing may be performed before radiation exposure. In some embodiments, the coating may be heated to 30°C to 300°C, in other embodiments to 50°C to 200°C, and in yet another embodiment to 80°C to 150°C. Heating (post-coating baking - PAB) may be performed for about 10 seconds to about 10 minutes in some embodiments, about 30 seconds to about 5 minutes in other embodiments, and about 45 seconds to about 2 minutes in yet another embodiment. Further ranges of temperatures and heating times within the aforementioned defined ranges are contemplated and envisioned.

[0117] Patterning of the composition:

[0118] Radiation can typically be directed onto a substrate using a mask, or the radiation beam can be controlled to scan the substrate. Radiation can generally include electromagnetic radiation, electron beams (beta radiation), or other suitable types. Electromagnetic radiation can typically have the desired wavelength or wavelength range, such as visible light, ultraviolet light, or X-rays. The achievable resolution of a radiation pattern generally depends on the radiation wavelength, and shorter wavelengths generally result in higher resolution patterns. Therefore, ultraviolet light, X-rays, or electron beams can ideally be used to achieve particularly high-resolution patterns.

[0119] According to the international standard ISO 21348 (2007) (which is incorporated herein by reference), ultraviolet light is defined as 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 several ways under acceptable 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. A 193 nm line from an argon fluoride laser can be used as a radiation source in FUV. EUV light at 13.5 nm has been used in photolithography, and this light is generated by a Xe or Sn plasma source excited using a high-energy laser or discharge pulse. Soft X-rays can be defined as those from greater than or equal to 0.1 nm to less than 10 nm.

[0120] Based on the design of the coating material, a large difference in material properties can exist between the irradiated area with the condensed coating material and the unirradiated coating material with substantially intact Sn-C bonds. For embodiments in which post-irradiation heat treatment is used, the post-irradiation heat (post-exposure baking - PEB) treatment can be performed at temperatures from about 45°C to about 250°C, in another embodiment from about 50°C to about 190°C, and in yet another embodiment from about 60°C to about 175°C. Post-exposure heating can typically be performed for at least about 0.1 minutes, in another embodiment from about 0.5 minutes to about 30 minutes, and in yet another embodiment from about 0.75 minutes to about 10 minutes. Those skilled in the art will recognize that additional ranges of post-irradiation heating temperatures and times within the aforementioned explicit ranges are considered and are within the scope of this disclosure. As described in the following sections, this large difference in material properties further facilitates the formation of high-resolution lines with smooth edges in the developed pattern.

[0121] For negative tone imaging, the developer can be an organic solvent, such as a solvent used to form the precursor solution. Typically, the choice of developer may be influenced by solubility parameters of both the irradiated and unirradiated coating materials, as well as the developer's volatility, flammability, toxicity, viscosity, and possible chemical interactions with other process materials. In particular, suitable developers include, for example, alcohols (e.g., 4-methyl-2-pentanol, 1-butanol, isopropanol, 1-propanol, methanol), ethyl lactate, ethers (e.g., tetrahydrofuran, dioxane, anisole), ketones (pentanone, hexanone, 2-heptanone, octanone), etc. Development can be performed from about 5 seconds to about 30 minutes, in another embodiment from about 8 seconds to about 15 minutes, and in yet another embodiment from about 10 seconds to about 10 minutes. Those skilled in the art will recognize that additional scopes beyond the explicit foregoing scope are considered and are within the scope of this disclosure. In addition to the main developer composition, the developer may also contain additional compositions to facilitate the development process. Suitable additives may include, for example, viscosity modifiers, solubilizers, or other processing aids. If optional additives are present, the developer may contain no more than about 10% by weight of the additive, and in other embodiments, no more than about 5% by weight of the additive. Those skilled in the art will recognize that other additive concentration ranges within the clearly defined ranges above are considered and are within the scope of this disclosure. A desirable developer composition is described in U.S. Patent Application 2020 / 0326627, entitled “Organometallic Photoresist Developer Composition and Processing Method”, by Jiang et al. (incorporated herein by reference).

[0122] In the case of weaker developers (e.g., dilute organic developers or compositions in which the coating has a low development rate), a higher-temperature development process can be used to increase the process rate. In the case of stronger developers, the development process temperature can be lower to reduce the rate and / or control the development kinetics. Typically, the development temperature can be adjusted between appropriate values ​​that correspond to the volatility of the solvent. Additionally, ultrasonic treatment can be used during development to disperse the developer with the dissolved coating material near the developer-coating interface. The developer can be applied to the patterned coating material using any reasonable method. For example, the developer can be sprayed onto the patterned coating material. Alternatively, 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 static form. If necessary, the development process can be completed using spin washing and / or drying. Suitable washing solutions include, for example, ultrapure water, aqueous tetraalkylammonium hydroxide, methanol, ethanol, propanol, and combinations thereof. After the image is developed, the coating material remains as a pattern on the substrate.

[0123] In some embodiments, solvent-free (dry) negative tone development processes can be performed using appropriate thermal or plasma development processes (such as those described by Tan et al. in PCT patent application number PCT / US2020 / 039615 entitled "Development of Photoresist Utilizing Halogen Chemistry" (which is incorporated herein by reference). For organotin photoresist coatings, dry development can be performed using halogen-containing plasmas and gases (e.g., HBr and BCl3). In some cases, dry development can offer advantages over wet development, such as reduced pattern collapse, reduced fouling, and fine control over the developer composition (i.e., plasma and / or etching gases). See also published U.S. Patent Application 2023 / 0408916 by De Schepper et al. entitled "Gas-based Development of Organometallic Resins in an Oxidizing Halogen Supply Environment" (which is incorporated herein by reference).

[0124] Specifically, for positive tone imaging, a suitable developer is typically an aqueous alkaline solution. In some embodiments, an aqueous alkaline solution can be used to obtain a sharper image. To reduce contamination from the developer, it is desirable to use a developer without metal atoms. Therefore, quaternary ammonium hydroxide compositions (such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, or combinations thereof) are ideal positive tone developers. Typically, quaternary ammonium hydroxides of particular interest can be represented by the formula R4NOH, where R = methyl, ethyl, propyl, butyl, or combinations thereof. The coating materials described herein can typically be developed with the same developers currently used for polymer resists, specifically tetramethylammonium hydroxide (TMAH). Commercially available TMAH is 2.38% by weight. Alternatively, mixed tetraalkyl quaternary ammonium hydroxides can be used. Typically, the developer may contain about 0.5 to about 30% by weight, in another embodiment about 1 to about 25% by weight, and in other embodiments about 1.25 to about 20% by weight of tetraalkylammonium hydroxide or similar quaternary ammonium hydroxide. Those skilled in the art will recognize that additional developer concentration ranges within the aforementioned explicit range are considered and are within the scope of this disclosure. For positive tone developers, assuming that unirradiated material is not significantly removed, it is ideal to dissolve material densified due to a relatively high radiation dose. This further broadens the process window. Further development improvements that promote positive tone development are described in U.S. Patent Application 2024 / 0085785 (hereinafter referred to as '785 application) entitled "Additives for Metal Oxide Photoresists, Positive Tone Development Using the Additives, and Double Baking Double Development Process" by Kasahara et al. (which is incorporated herein by reference).

[0125] Organotin resists are commonly used for both negative and positive tone patterning. There are no particular limitations on the patterns formed using organotin resists, and they can typically include complex layouts based on various mask patterns used for device fabrication. Masks, including line / space and / or contact hole patterns, can be particularly useful for testing photoresist performance. In some embodiments, the pattern can be based on lines with regular intervals having patterned gaps (i.e., line / space patterns) or holes on a grid (i.e., contact hole patterns). The formation of holes on a grid is particularly suitable for positive tone patterning. For negative patterning of holes, the area surrounding the hole is illuminated, in which case the hole is affected by secondary electrons and shot noise from all directions, making the hole prone to having a large amount of residue. As demonstrated below, positive tone patterning of holes can be performed efficiently using the methods described herein.

[0126] Cleaning with an inert liquid (such as deionized water) can be used to remove residual developer. After the development step, the coating material can be heat-treated to further condense the material and further dehydrate, densify, or remove residual developer or cleaning solution from the material. This heat treatment can be particularly ideal for embodiments in which the oxide coating material is incorporated into the final device, but if stabilization of the coating material is required to facilitate further patterning, heat treatment can be ideal for some embodiments in which the coating material is used as a resist for pattern transfer and is eventually removed. In particular, the patterned coating material can be baked under conditions that allow the patterned coating material to exhibit the desired level of etch selectivity. To distinguish this heating step, it can be referred to as hard baking. In some embodiments, the patterned coating material can be heated to about 100°C to about 600°C, in other embodiments about 175°C to about 500°C, and in still other embodiments about 200°C to about 400°C. Heating can be performed for at least about 1 minute, in other embodiments about 2 minutes to about 1 hour, and in still other embodiments about 2.5 minutes to about 25 minutes. Heating can be performed in air, vacuum, or an inert gas environment such as Ar or N2. Those skilled in the art will recognize that ranges of temperature and time for other heat treatments within the aforementioned specific scope are considered and are within the scope of this disclosure. Similarly, non-heat treatments (including blanket UV exposure or exposure to oxidizing plasmas such as O2) can also be used for similar purposes.

[0127] Example

[0128] Example 1: 2,2-Dimethoxy-5-pentyltin tris(tert-butyloxy) (CH3C(OMe)2CH2CH2CH2Sn) Synthesis of (OtBu)3)

[0129] This embodiment describes a method for one-pot direct synthesis of organotin trialkyl oxides with acetal ligands.

[0130]

[0131] The potassium-tin trialkyloxide reactant (KSn(OtBu)3) was prepared as described in application '658 and purified to a solid compound. The KSn(OtBu)3 reactant, 0.4 molar equivalents (relative to 1 molar equivalent of tin) of tetrabutylammonium iodide ((n-Bu)4N(I)) as a catalyst, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a reaction solution with a concentration of approximately 0.10 g KSn(OtBu)3 / ml toluene. The solution was mixed at room temperature. Then, 1.2 molar equivalents of 5-chloro-2,2-dimethoxypentane relative to KSn(OtBu)3 were added to the reaction solution. The reaction mixture was then heated to 80°C and stirred for 3 days. Afterwards, volatiles were removed under vacuum, and the remaining residue was filtered through a diatomaceous earth bed using pentane. The filtrate was vacuum-distilled to give the title compound. The characteristics of the product were confirmed by NMR. 1 H NMR (C6D6) δ 1.21 (s, 3H), 1.29 (t, 2H), 1.43 (s, 27H), 1.77 + 1.81 (m,4H), 3.07 (s, 6H); 119 Sn NMR (pure) δ -197.

[0132] This embodiment demonstrates a method for the direct synthesis of organotin trialkyloxides with acetal groups and high specificity for single organic groups. No dialkyl-tin compounds were detected.

[0133] Example 2: 2-Methyl-2-(3-propyltin tris(tert-butoxy))1,3-dioxacyclopentane (CH3(CO2CH2CH2)) Synthesis of CH2CH2CH2Sn(OtBu)3)

[0134] This embodiment describes a method for one-pot direct synthesis of organotin trialkyl oxides having ligands with cyclic bonds between acetal oxygen atoms.

[0135]

[0136] The KSn(OtBu)3 reactant prepared as described in Example 1, 0.5 molar equivalents of tetrabutylammonium iodide, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a reaction solution with a concentration of approximately 0.10 g KSn(OtBu)3 / ml toluene. The solution was mixed at room temperature. Then, 1.0 molar equivalent of 2-methyl-2-(3-chloropropyl)-1,3-dioxane (commercially available) was added to the reaction solution. The reaction mixture was then heated to 80°C and stirred for 3 days. Afterward, volatiles were removed under vacuum, and the remaining residue was filtered through a diatomaceous earth bed using pentane. The filtrate was vacuum-distilled to give the title compound. The characteristics of the product were confirmed by NMR. 1H NMR (C6D6) δ 1.28(s, 3H), 1.34 (t, 2H), 1.43 (s, 27H), 1.77 (t, 2H), 1.93 (t, 2H), 3.52 (m,2H), 3.55 (m, 2H); 119 Sn NMR (pure) δ -198.

[0137] This embodiment demonstrates a method for the direct synthesis of organotin trialkyl oxides with cyclic acetal groups and high specificity for single organic groups.

[0138] Example 3: 2-(2-ethyltin tri(tert-butoxy))1,3-dioxacyclopentane ((CO2CH2CH2)CH2CH2Sn) Synthesis of (OtBu)3)

[0139] This embodiment describes a method for one-pot direct synthesis of organotin trialkyl oxides having ligands with cyclic bonds between acetal oxygen atoms.

[0140]

[0141] The KSn(OtBu)3 reactant prepared as described in Example 1, 0.2 molar equivalents of tetrabutylammonium iodide, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a reaction solution with a concentration of approximately 0.10 g KSn(OtBu)3 / ml toluene. The solution was mixed at room temperature. Then, 1.1 molar equivalents of 2-(iodoethyl)-1,3-dioxane were added to the reaction solution. The reaction mixture was then heated to 80°C and stirred for 3 days. Afterward, volatiles were removed under vacuum, and the remaining residue was filtered through a diatomaceous earth bed using pentane. The filtrate was vacuum-distilled to obtain the title compound. The properties of the product composition were confirmed using NMR. 1 H NMR (C6D6) δ 1.39 (t, 2H), 1.46 (s, 27H), 2.08 (dt, 2H), 3.33 (t, 2H), 3.67 (t, 2H), 4.76 (t, 1H); 119 Sn NMR (pure) δ -221.

[0142] This embodiment demonstrates a method for the direct synthesis of organotin trialkyl oxides with cyclic acetal groups and high specificity for single organic groups.

[0143] Example 4: 4-((4,5-di(trifluoromethyl))benzodioxane-pentadiene)-pentyltin tri(tert-butoxy) synthesis

[0144] This embodiment describes a method for synthesizing a fluorinated aromatic acetal organotin compound represented by the product of reaction scheme 1. The method is based on the following synthetic strategy.

[0145]

[0146] (Option 1)

[0147] Part A. Preparation of 1,2-diiodo-4,5-dimethoxybenzene

[0148]

[0149] H₅IO₆ (0.41 equivalents) and methanol were added to a pre-dried double-necked round-bottom flask equipped with a 6-inch Vigreux column and two Schlenk adapters. The mixture was stirred at room temperature, and then I₂ (0.8 equivalents) was added. The reaction was stirred for 10 minutes under a continuous argon flow, followed by the addition of 1,2-dimethoxybenzene (1 equivalent) via a syringe. The reaction was then heated to 70 °C and maintained for 5 h. The hot solution was then poured into a dilute aqueous solution of Na₂S₂O₅ and stirred overnight. The solution was then filtered through a medium-sized glass filter, and the resulting solid was washed with cold methanol and then dried under vacuum to give a colorless crystalline solid of the title compound (1,2-diiodo-4,5-dimethoxybenzene). The properties of the product composition were confirmed using NMR. 1 H NMR (400 MHz, CDCl3): δ = 7.26 (s, 2H), 3.86 (s, 6H) ppm.

[0150] Part B. Preparation of 4,5-Diiodo-1,2-benzenediol

[0151]

[0152] One equivalent of the product from part A (1,2-diiodo-4,5-dimethoxybenzene) was added to a pre-dried round-bottom flask equipped with a Schlenk connector. The flask was then purged / refilled with a continuous stream of argon. Anhydrous dichloromethane (DCM) was added, and the solution was stirred and cooled to 0°C. BBr3 (2 equivalents, 1M DCM) was slowly added through a tube. The reaction was stirred at 0°C for 4 h, followed by slow addition of H2O through a feeding funnel. The solution was placed in a separatory funnel, and the organic matter was collected. The aqueous layer was extracted with Et2O. The organic matter was combined, washed successively with aqueous Na2S2O3 solution, water, and brine, dried over MgSO4, and filtered through a silica column. The volatiles were removed under reduced pressure to give a colorless solid of the title compound (4,5-diiodo-1,2-benzenediol). The properties of the product composition were confirmed using NMR. 1H NMR (400 MHz, CDCl3): δ = 7.37 (s, 2H), 5.23 (s, 2H) ppm.

[0153] Part C. Preparation of 4-chloro-1-methyl(4,5-diiodo)benzodioxane.

[0154]

[0155] One equivalent of the product from part B (4,5-diiodo-1,2-benzenediol) was added to a pre-dried round-bottom flask equipped with a Schlenk connector. The flask was then purged / refilled with a continuous stream of argon. Anhydrous toluene was added, followed by hexamethyldisilazane (HN(SiMe3)2, 1.05 equivalent). The reaction mixture was then heated to 105°C and stirred for 2 h. The temperature was then lowered to 55°C, and volatiles were removed under reduced pressure. Once purged, the residue was cooled to room temperature, and anhydrous DCM was added. The solution was stirred while adding 5-chloro-2-pentanone (1 equivalent), followed by the slow addition of trimethylsilyl trifluoromethanesulfonate (Me3SiOTf). The reaction mixture was sealed and stirred overnight. The volatiles were then removed under reduced pressure, and the residue was dissolved in a 5% Et2O solution in pentane and filtered through a silica column. The filtrate was concentrated to give an oily solid. The solid was dissolved in pentane at 50 °C and then placed at -20 °C to grow crystals. The solvent was decanted from the crystals, and the crystals were washed with cold pentane. Residual pentane was then removed from the crystals under reduced pressure. The product was isolated as a colorless crystalline solid of the title compound (4-chloro-1-methyl(4,5-diiodo)benzodioxane). The properties of the product composition were confirmed using NMR. 1 H NMR (400 MHz, CDCl3): δ = 7.25 (s, 2H), 3.58 (t, 2H), 2.11 (m,2H), 1.94 (m, 2H), 1.64 (s, 3H) ppm.

[0156] Part D. Preparation of 4-chloro-1-methyl(4,5-di(trifluoromethyl))benzodioxane.

[0157]

[0158] In an argon-filled glove box, freshly purified cuprous bromide (I) (CuBr, 4.5 equivalents) was added to a pre-dried round-bottom flask fitted with a Schlenk connector. The flask was transferred to a Schlenk line under a continuous argon flow, where anhydrous dimethylformamide (DMF) was added via a tube, followed by (trifluoromethyl)trimethylsilane (Me3SiCF3, 3.75 equivalents) via a syringe. The solution was stirred and cooled to 0°C, and potassium fluoride (KF, 3.8 equivalents) was added directly. Then, 1,3-dimethyl-2-imidazolium ketone (DMI) was added, and the mixture was stirred at 0°C for 3 h. Next, an equivalent of the product from the C-part (4-chloro-1-methyl(4,5-diiodo)benzodioxane) was added, followed by additional DMI. The reaction mixture was heated to 35°C, sealed, and stirred for at least 30 h. 19 The reaction progress was monitored by 1F NMR spectroscopy. The reaction was allowed to proceed until the area change of the CF resonance associated with the subject compound was negligible at selected time intervals, typically approximately every eight hours or overnight. Then, Et₂O and water were added to the reaction mixture. The precipitated organic matter was collected. The aqueous phase was then extracted with additional Et₂O to recover further organic matter. The organic matter was combined. The organic matter was washed with water and brine, dried over MgSO₄, and filtered. The filtrate was concentrated under reduced pressure, and the residue was purified by column chromatography to give the title compound (4-chloro-1-methyl(4,5-di(trifluoromethyl))benzodioxane). The characteristics of the product composition were confirmed using NMR. 1 H NMR (400 MHz, CDCl3): δ = 7.19 (s, 2H), 3.59 (t,2H), 2.19 (m, 2H), 2.00 (m, 2H), 1.73 (s, 3H) ppm. 19 F NMR (282 MHz, CDCl3): δ= -58.20 (s) ppm.

[0159] Part E. Preparation of 4-((4,5-di(trifluoromethyl))benzodioxane-pentadiene)-pentyltin tri(tert-butoxy)

[0160]

[0161] In an argon glove box, one equivalent of the product from part D (4-chloro-1-methyl(4,5-di(trifluoromethyl))benzodioxane) and one equivalent of tri(tert-butoxy)potassium tin (KSn(O)) are placed in the atmosphere. tBu)3 and 0.5 equivalents of tetrabutylammonium iodide (TBAI) were added to a pre-dried round-bottom flask equipped with a Schlenk connector. The flask was transferred to a Schlenk line under a continuous argon flow, and the reaction mixture was stirred at 80°C for at least 50 h. 119 The reaction progress was monitored using Sn NMR spectroscopy. The reaction was allowed to proceed until the area change of the peak associated with the title compound was negligible. The reaction mixture was then cooled to room temperature, and volatiles were removed under reduced pressure. The resulting residue was mixed with pentane, and the mixture was filtered through diatomaceous earth. The filtrate was concentrated under reduced pressure, and low-boiling impurities were removed by distillation at 90 °C (30 mTorr). The final product was distilled at 115 °C (30 mTorr) as a colorless oil of the title compound (4-((4,5-di(trifluoromethyl))benzodioxanepentadiene)-pentyltin tri(tert-butyloxy)). The properties of the product composition were confirmed using NMR. 119 Sn NMR (112 MHz, pure): δ = -197.66 (s) ppm. 1 H NMR (400 MHz, C6D6): δ = 6.88 (s, 2H), 1.79 (m,4H), 1.38 (s, 27H), 1.27 (s, 3H), 1.18 (t, 2H) ppm. 19 F NMR (282 MHz, pure): δ = -57.90 (s) ppm.

[0162] This embodiment describes the multi-step synthesis of the fluorinated aromatic acetal organotin compound 4-((4,5-di(trifluoromethyl))benzodioxanepentadiene)-pentyltin tri(tert-butyloxy)

[0163] Example 5: Synthesis of 4-((4,5-diiodo)benzodioxane)-pentyltin tri(tert-butyloxy)

[0164] This embodiment describes a method for synthesizing an iodinated aromatic acetal organotin compound represented by reaction scheme 2 from the product of part C of Example 4. The method is based on the following reaction.

[0165]

[0166] (Option 2)

[0167] In an argon glove box, one equivalent of the product from part C of Example 4 (4-chloro-1-methyl(4,5-diiodo)benzodioxane) and one equivalent of tris(tert-butoxy)potassium tin (KSn(O)) were placed in the atmosphere. tBu)3) and 0.5 equivalents of tetrabutylammonium iodide (TBAI) were added to a pre-dried round-bottom flask equipped with a Schlenk connector. The flask was transferred to a Schlenk line under a continuous argon flow, and the reaction mixture was stirred at 80°C for at least 50 h. 119 The reaction progress was monitored using Sn NMR spectroscopy. The reaction was allowed to proceed until the area change of the peak associated with the title compound was negligible. The reaction mixture was then cooled to room temperature, and volatiles were removed under reduced pressure. The resulting residue was mixed with pentane, and the mixture was filtered through diatomaceous earth. The filtrate was then concentrated under reduced pressure, and low-boiling impurities were removed by distillation at 110 °C (30 mTorr) to provide the title compound (4-((4,5-diiodo)benzodioxanepentadiene)-pentyltintri(tert-butoxy)). The characteristics of the product composition were confirmed using NMR. 119 Sn NMR (112 MHz, pure): δ = -197.73 ppm. 1 H NMR (400 MHz, C6D6): δ = 7.06 (s, 2H), 1.78 (m, 4H), 1.40 (s, 27H), 1.24 (s, 3H), 1.18 (t, 2H) ppm.

[0168] This embodiment demonstrates a method for synthesizing organotin compounds of iodinated aromatic acetals. This compound can be used in blends of organotin compositions, for example, by providing improved EUV absorption.

[0169] Example 6: 2-(1-methyl-3-propyltin tris(tert-butoxy))1,3-(3-fluorobenzo)dioxane Synthesis of (FBD)

[0170] This embodiment describes a method for synthesizing fluorinated aromatic acetal organotin compounds represented by formula (9).

[0171]

[0172] Part A. Synthesis of 1-fluoro-2,3-bis(trimethylsiloxy)-benzene (C6FH3O2(Si(CH3)3)2)

[0173] 3-Fluoro-catechol, 1 molar equivalent of hexamethyldisilazane, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a reaction solution with a concentration of approximately 0.10 g 3-fluorocatechol / ml toluene. The reaction mixture was then refluxed for 3 hours. Afterward, volatiles were removed under vacuum, and the resulting oil was purified using a silica column with hexane as the eluent. The eluent was then evacuated to obtain the purified product of the title compound. The characteristics of the product were confirmed by NMR. 1H NMR (CDCl3) δ 0.28 (d, 9H), 0.29 (s, 9H), 6.64 (m, 1H), 6.73 (m, 1H), 6.77 ppm (m, 1H).

[0174] Part B. Synthesis of 2-(1-methyl-3-chloropropane)-1,3-(3-fluorobenzo)dioxane (FBD-Cl)

[0175] 5-Chloropropane was dissolved in dichloromethane (10 mL / g feedstock) and mixed with 1 molar equivalent of the product from part A (1-fluoro-2,3-bis(trimethylsiloxy)-benzene) and 0.17 molar equivalent of trimethylsilyl trifluoromethanesulfonate under an inert atmosphere. The reaction mixture was stirred overnight at room temperature. Volatiles were then removed under vacuum, and the crude oil was purified by column chromatography using 5% diethyl ether in hexane as the eluent. The eluent was then evacuated and distilled to obtain the purified product of the title compound. The characteristics of the product (CH3(CO2C6H3F)CH2CH2CH2Cl) were confirmed by NMR. 1 H NMR(CDCl3) δ 1.70 (s, 3H), 2.01 (m, 2H), 2.17 (m, 2H), 3.60 (t, 2H), 6.58 (d,1H), 6.65 (t, 1H), 6.74 ppm (m, 1H); 19 F NMR (CDCl3) -139 ppm.

[0176] Part C. Synthesis of 2-(1-methyl-3-propyltin tris(tert-butoxy))1,3-(3-fluorobenzo)dioxane (FBD)

[0177] The KSn(OtBu)3 reactant prepared as described in Example 1, 0.4 molar equivalents of tetrabutylammonium iodide, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a reaction solution with a concentration of approximately 0.10 g KSn(OtBu)3 / ml toluene. The solution was mixed at room temperature. Then, 1.1 molar equivalents of the product from part B (2-(1-methyl-3-chloropropane)1,3-(3-fluorobenzo)dioxane) were added to the reaction solution. The reaction mixture was then heated to 80°C and stirred for 2 days. Afterward, volatiles were removed under vacuum, and the remaining residue was filtered through a diatomaceous earth bed using pentane. The filtrate was vacuum-distilled to give the title compound. The characteristics of the product ((CH3(CO2C6H3F)CH2CH2CH2Sn(OtBu)3) were confirmed by NMR. 1H NMR (C6D6) δ 1.19 (t, 2H), 1.34 (s, 3H), 1.41 (s, 27H), 1.88 (m, 4H), 6.37 (m, 1H), 6.39 (d, 1H), 6.45 ppm (m, 1H); 119 Sn NMR (pure) δ -200 ppm; 19 F NMR (pure) δ -142 ppm.

[0178] This embodiment describes the multi-step synthesis of a fluorinated aromatic acetal organotin compound represented by the formula (CH3(CO2C6H3F)CH2CH2CH2Sn(OtBu)3).

[0179] Example 7: 2-(3-propyltin tri(tert-butoxy))-2-(1-vinyl)-1,3-dioxane (CH2CH Synthesis of (CO2C2H4)CH2CH2CH2Sn(OtBu)3

[0180] This embodiment describes a method for synthesizing an unsaturated organotin acetal compound represented by formula (10).

[0181]

[0182] Part A. Synthesis of 2-(3-chloropropyl)-2-(2-bromoethyl)-1,3-dioxacyclopentane (ClCH2CH2CH2(CO2CH2CH2)CH2CH2Br)

[0183] 1-Bromo-6-chloro-3-hexanone was synthesized using the method of Saruengkhanphasit (Rungroj Saruengkhanphasit, Darren Collier, and Iain Coldham, The Journal of Organic Chemistry 2017 82 (12), 6489-6496. DOI:10.1021 / acs.joc.7b00959) (which is incorporated herein by reference). 1-Bromo-6-chloro-3-hexanone was dissolved in toluene and mixed with ethylene glycol (1.1 equivalents) and p-toluenesulfonic acid monohydrate (0.1 equivalents). The reaction mixture was refluxed overnight in a Dean-Stark apparatus. An aqueous workup was performed using a saturated sodium bicarbonate solution and diethyl ether. Volatiles in the organic extract were removed under vacuum, and the resulting oil was purified by passing it through a silica column using 5% diethyl ether in hexane as the eluent. The volatiles were removed under vacuum, and the product (ClCH2CH2CH2(CO2CH2CH2)CH2CH2Br) was distilled for purification. 1H NMR (CDCl3) δ1.80 (m, 2H), 1.88 (m, 2H), 2.25 (t, 2H), 3.42 (t, 2H), 3.58 (t, 2H), 3.98ppm (s, 4H).

[0184] Part B. Synthesis of 2-(3-chloropropyl)-2-(1-vinyl)-1,3-dioxacyclopentane (ClCH2CH2CH2(CO2CH2CH2)CHCH2)

[0185] The product from part A (2-(3-chloropropyl)-2-(2-bromoethyl)-1,3-dioxane) was mixed with 1 molar equivalent of potassium tert-butoxide in tetrahydrofuran under an inert atmosphere. The reaction mixture was stirred at room temperature for 45 minutes. Afterwards, volatiles were removed under vacuum. The characteristics of the product (ClCH2CH2CH2(CO2CH2CH2)CHCH2) were confirmed by NMR. 1 HNMR (CDCl3) δ 1.87 (m, 4H), 3.58 (t, 2H), 3.89 (m, 2H), 3.96 (m, 2H), 5.19 (d, 1H), 5.39 (d, 1H), 5.72 ppm (dd, 1H).

[0186] Part C. Synthesis of 2-(3-propyltin tri(tert-butoxy))-2-(1-vinyl)-1,3-dioxane (CH2CH(CO2C2H4)CH2CH2CH2Sn(OtBu)3)

[0187] The KSn(OtBu)3 reactant prepared as described in Example 1, 0.7 molar equivalents of tetrabutylammonium iodide, and toluene were added to a reaction vessel under an inert atmosphere and mixed to form a reaction solution with a concentration of approximately 0.10 g KSn(OtBu)3 / ml toluene. The solution was mixed at room temperature. Then, 1.1 molar equivalents of the product from part B (2-(3-chloropropyl)-2-(1-vinyl)-1,3-dioxane) were added to the reaction solution. The reaction mixture was then heated to 80°C and stirred for 4 days. Afterward, volatiles were removed under vacuum, and the remaining residue was filtered through a diatomaceous earth bed using pentane. The filtrate was vacuum-distilled to give the title compound. The characteristics of the product (CH2CH(CO2C2H4)CH2CH2CH2Sn(OtBu)3) were confirmed by NMR. 1H NMR (C6D6) δ 1.34 (t, 2H), 1.41 (s, 27H), 1.86 (m,2H), 1.95 (m, 2H), 3.47 (m, 2H), 3.53 (m, 2H), 5.01 (d, 1H), 5.37 (d, 1H), 5.70 ppm (dd, 1H). 119 Sn NMR (C6D6) δ -197 ppm.

[0188] This embodiment describes the multi-step synthesis of an unsaturated organotin acetal compound represented by the formula CH2CH(CO2C2H4)CH2CH2CH2Sn(OtBu)3.

[0189] Example 8: Synthesis of hydrophobic, large non-ketal ligand organotin precursors for blend precursor coatings

[0190] Part A: Synthesis of phenylisopropyl Sn(NMe2)3

[0191] Sn(NMe2)4 (5.5 gm, 18.64 mmol) was dissolved in 30 mL of pentane, and potassium cumene (3 gm, 18.83 mmol - prepared according to the method in Angew. Chem. Int. Ed. 2020, 59, 22460) was slowly added to the solution in several portions inside a glove box. The reaction mixture was stirred at room temperature for another 2 hours. During the reaction, a brown precipitate and a clear pentane solution were formed. The precipitate was filtered through diatomaceous earth to obtain a clear pentane solution. The solvent was removed under vacuum to obtain phenylisopropyl Sn(NMe2)3, a colorless liquid, in 43% yield. 119 Sn NMR δ = -110.5ppm.

[0192] Part B: Conversion to phenylisopropyl Sn(O) t Bu)3

[0193] Phenylisopropyl Sn(NMe2)3 (3 gm, 8.08 mmol) was added to a flask and cooled to 0 °C. Tert-butanol (1.85 gm, 25.05 mmol) was added under a nitrogen atmosphere. The reaction mixture was heated to room temperature and stirred for 30 minutes. A colorless oil was obtained, which was further purified by distillation to give phenylisopropyl Sn(O2)3. t Bu)3, with a yield of 90%. 119 Sn NMR (pure) δ = -281.4 ppm. 1H NMR (400 MHz, neat) δ = 7.31 (m, 2H, ArH), δ 7.11 (m, 2H, ArH), δ 6.96 (m, 1H, ArH), δ 1.59 (m, 6H, 2CH3), δ 1.10 (m,27H, 3C(CH3)3).

[0194] Example 9. Solubility of organotin coatings with acetal ligands

[0195] This embodiment demonstrates the preparation of a coating solution containing an organotin compound with an acetal group, and the formation of a hydrophilic film from this coating solution. The solubility of the coating after the post-coating baking step was determined. A comparison was made with an organotin coating without an acetal ligand.

[0196] Coating solutions were prepared from the organotin compounds prepared in Examples 1-3. Appropriate amounts of each organotin compound were dissolved in 4-methyl-2-pentanol or 1-propanol (each solvent having a water content of 300 ppm) to form the resist solutions shown in Table 1. The applicant's LA commercial monoalkyltin photoresist was used as a comparative example.

[0197] Table 1

[0198]

[0199] Each resist precursor solution (Al-C2) was spin-coated onto individual Si wafers (each with a 100 nm thermal oxide layer) to form a set of coated wafers. After deposition, each wafer was baked at 100°C, 150°C, or 180°C for 2 minutes (post-coating baking - PAB). Each coated wafer was then immersed in a selected developer for 30 seconds and dried with nitrogen. The developed wafers were then evaluated visually and assigned values ​​as follows: "Y" for films substantially removed by the developer, "partial" for films partially removed by the developer, and "N" for films substantially not removed by the developer. The results are shown in Table 2.

[0200] Table 2

[0201]

[0202]

[0203] The results showed that the films exhibited good solubility in various developers. Notably, after baking at a low temperature of 100°C, all films derived from the acetal precursor showed at least partial solubility in water. This indicates that the presence of the acetal functional group imparts high polarity to the organotin films, thus improving their solubility in water and aqueous systems. Similarly, for all PAB conditions, each film showed at least partial solubility in a 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution, further demonstrating that the acetal functional group imparts significant polarity and hydrophilicity to the organotin films. In contrast, under any PAB conditions, the organotin coating with non-acetal ligands (comparative example) did not show solubility in water or TMAH.

[0204] The results show that acetal ligand precursors can be used in blends for positive tinting treatment, which is further supported in the following examples.

[0205] Example 10. Thermal stability of organotin coatings with acetal ligands

[0206] This embodiment describes the preparation of organotin films using organotin precursors containing ligands with acetal groups, demonstrating that films prepared using these precursors exhibit improved thermal stability.

[0207] Five precursor solutions were prepared. Precursor solutions S1-S3 were formed from organotin tri(tert-butoxy) precursors containing ligands with acetal groups. Precursor solutions S4 and S5 were formed from organotin tri(tert-butoxy) precursors containing ligands without acetal groups.

[0208] The first precursor solution (S1) is prepared by dissolving an appropriate amount of 2-methyl-2-(3-propyltin tri(tert-butoxy))1,3-dioxane from Example 2 in 4-methyl-2-pentanol to form an organotin solution with a Sn concentration of 0.05 M [Sn]. The second precursor solution (S2) is prepared by dissolving an appropriate amount of 2-(2-ethyltin tri(tert-butoxy))1,3-dioxane from Example 3 in 4-methyl-2-pentanol to form an organotin solution with a Sn concentration of 0.05 M [Sn]. The third precursor solution (S3) is prepared as described in Example 9 regarding resist solution C1. The fourth precursor solution (S4) is prepared by dissolving an organotin compound of formula (11) having a nonpolar organic ligand bonded to Sn in 4-methyl-2-pentanol to form an organotin solution with a Sn concentration of 0.05 M [Sn]. The organotin precursor of formula 11 is as described in Example 8. The fifth precursor solution (S5) is prepared by dissolving an organotin compound of formula (12) having a nonpolar organic ligand bonded to Sn in 1-propanol to form an organotin solution with a Sn concentration of 0.05 M [Sn]. The organotin precursor of formula (12) is synthesized by conversion of the corresponding triamine compound, which is synthesized by Grignard reagent according to the method described in U.S. Patent No. 10,787,466 (hereinafter referred to as '466 Patent) entitled "Monoalkyltin Compounds with Low Polyalkyl Pollution, Compositions Thereof and Methods" by Edson et al. (which is incorporated herein by reference).

[0209]

[0210] Each precursor solution (S1-S5) was spin-coated at 1500 rpm for 45 s onto a separate undoped Si wafer, resulting in a set of film samples (F1-F5). The average thickness of each film sample was approximately 20-26 nm. The film thickness was measured using ellipsometry. The coated wafers were then diced into chips approximately 1 inch in size. The chips coated with film samples F1-F5 were either baked on a hot plate at a selected temperature ranging from 50°C to 300°C for 2 minutes, or not baked at all.

[0211] After the selected baking steps for the F1-F5 membrane samples were completed, the membranes were analyzed by FTIR. For each sample, measurements were taken at 3000 to 2850 cm⁻¹ corresponding to the alkyl CH stretching region. -1The sum of the peak areas between the two films is normalized by dividing by the initial film thickness. The normalized peak area is calculated by dividing the thickness-normalized peak area of ​​each baked film by the thickness-normalized peak area of ​​the corresponding unbaked film.

[0212] Figure 3 The normalized peak areas (as a function of baking temperature) for membrane samples F1-F5 are shown. Data points for the unbaked membranes in the figure are shown at approximately 0°C, with peak areas normalized relative to these data points. The thermal stability of each ligand type (acetal vs. non-acetal) was examined... Figure 3 The FTIR curves were used for evaluation. At low temperatures, FTIR results showed a slow loss of alkyl absorption, as indicated by the gentle slope of the curves. This slow loss of alkyl absorption at low temperatures is generally attributed to the loss of bound solvent and / or membrane densification, although some loss due to ligand rearrangement or reactions cannot be completely ruled out. However, at a relatively high temperature, each sample showed a sharp decrease in alkyl absorption, attributed to the pyrolysis of the R-Sn bonds. The decomposition temperature of the membrane was qualitatively determined by identifying the temperature at which 80% of the normalized peak area was observed, and the results are provided in Table 3.

[0213] Table 3

[0214]

[0215] FTIR results showed that the films with acetal-containing ligands exhibited relatively high thermal stability, with no significant loss of CH absorption observed up to approximately 180 °C. In contrast, sample F4 showed a sharp loss of CH absorption after approximately 159 °C, which is related to the lower thermal stability of the C-Sn bond. Sample F5, the non-acetal ligand compound, showed a maximum thermal decomposition temperature of approximately 222 °C, indicating significant thermal stability of the Sn-C bond. Overall, the results demonstrate the use of modified blends between organotin compounds with acetal-containing ligands and organotin compounds with ligands without acetal groups. Such blends can provide photoresist films with thermal stability suitable for a wider range of processing conditions, as well as films containing one or more components with significantly different thermal stabilities, where selective decomposition of a ligand can be achieved.

[0216] This embodiment demonstrates that organotin films prepared using organotin precursors containing acetal ligands can exhibit relatively high thermal stability.

[0217] Example 11. Positive tonal contrast curves of organotin resist blends and controls

[0218] This embodiment demonstrates the solubility of organotin resist coatings, which is beneficial for improving the positive color treatment of blends containing organotin compounds with acetal ligands.

[0219] A series of photoresist solutions were prepared from the organotin precursor compounds listed in Table 4. Compound K1 was synthesized as described in Example 2. Compound P2 was synthesized as described in the above-cited '658 application. Compound P1 was synthesized as described in Example 8.

[0220] Table 4

[0221]

[0222] The compounds were combined in various ratios into a solvent blend of 38 wt% 1-pentanol / 62 wt% 1-propanol with a total water concentration of 300 ppm to obtain a solution with a total Sn concentration of 0.038 M [Sn] and having molar ratios of P1, P2 and K1 according to Table 5.

[0223] Table 5

[0224]

[0225] Resist solutions A and B are prepared from blends of two organotin compounds, P1 and K1. P1 has a nonpolar ligand that binds to tin, while K1 has a ligand containing a polar acetal functional group. Resist solution C is prepared from a ternary mixture of P1, P2, and K1. P2 is an organotin compound with a fluorinated nonacetal ligand. Resist solutions CE1 and CE2 are a monocomponent composition and a blend of organotin compounds without acetal functional groups, respectively.

[0226] A photoresist solution was spin-coated onto a circular 300 mm Si wafer with an approximately 10 nm spin-coated glass (SOG) layer to form a photoresist coating. The coated wafer was then subjected to PAB at 100 °C for 60 s. The film thickness, including the SOG layer, of each blend-coated wafer was measured using ellipsometry, yielding film thicknesses of 22.1 nm, 22.0 nm, 22.3 nm, 21.8 nm, and 22.5 nm for samples A, B, C, CE1, and CE2, respectively.

[0227] Following PAB, each wafer is then exposed on an ASML TwinScan NXE3400 EUV exposure tool to create a contrast array of exposed areas (i.e., pads) on each wafer, where each exposed area is subjected to approximately 1 mJ / cm². 2 Approximately 100 mJ / cm 2Different doses of radiation were applied. After EUV exposure, the films were then subjected to post-exposure baking (PEB) at 100°C, 120°C, or 140°C for 60 seconds. Each wafer was then developed with 2.38 wt% TMAH, followed by rinsing with water to remove residual TMAH. Finally, the wafers were hard baked at 250°C for 60 seconds. After hard baking, the thickness of each exposed region was measured to create a thickness-to-dose graph for each wafer, thus generating a contrast profile for each wafer.

[0228] After hard baking, the thickness of each wafer is measured to create a graph of the wafer's thickness relative to the dose, thereby creating a contrast curve for each wafer. Figure 4 and 5 Contrast curves of PEB-coated wafers prepared from resist solutions A, B, and CE1 and subjected to 100°C or 120°C are shown respectively. Figure 6 The contrast curves of PEB-coated wafers prepared from resist solutions C and CE2 and subjected to 100°C are shown. Figure 7 Contrast curves are shown for PEB-coated wafers prepared with resist solution A and subjected to 100°C or 140°C.

[0229] Reference Figure 4 Compared to wafers coated with resist solution CE1, wafers coated with resist solutions A and B exhibited solubility at lower positive hue dosages. Wafers coated with resist solutions A and B showed solubility up to approximately 90 mJ / cm². 2 No high-dose insolubility (i.e., no condensation cliff) was observed at the highest EUV dose used. The results indicate that at low doses, the coating is generally insoluble in the developer and resistant to removal. However, with increasing radiation doses, sufficient removal of hydrophobic ligands from the coating material allows for coating dissolution. At sufficiently high doses, Figure 4 , 5 The results in Figures 6 and 7 show that coatings prepared from resist solutions C, CE1, and CE2 undergo significant condensation and form condensation cliffs, rendering the coatings insoluble again. The results also indicate that for compositions containing ligands with acetal functional groups, higher PEB temperatures can lead to the formation of condensation cliffs. Contrast curves of wafers subjected to PEB at 100°C or 120°C will be shown, respectively. Figure 4 and Figure 5 In comparison, resist samples A and B showed a high amount of insoluble condensate material under PEB at 120°C, while such a high amount of insoluble condensate material was not present in the sample subjected to lower PEB at 100°C. Figure 7This effect is highlighted again in the figure, where the contrast curve generated by resist sample A shows a condensation cliff for PEB at 140°C, but no condensation cliff for PEB at 100°C. Figure 5 Similar results were shown, where, under the condition of higher temperature PEB at 120°C, wafers coated with resist solutions A and B exhibited solubility at lower positive hue doses compared to wafers coated with resist solution CE1. (Compared to PEB at 100°C...) Figure 4 Compared to ), at 120℃ PEB ( Figure 5 At lower doses, condensation cliffs appear, but coated wafers (A and B) containing acetal ligand K1 require higher doses to exhibit condensation cliffs, thus effectively providing a larger positive tone process window compared to wafers coated with resist solution CE1. Furthermore, coated wafers coated with resist solution CE have a higher minimum thickness compared to wafers coated with resist solutions A and B, indicating lower solubility and incomplete development of the exposed products, which could lead to defects such as scale or microbridges.

[0230] The results also showed that using higher PEB temperatures could help reduce the amount of positive hue required for patterning. (See reference) Figure 7 Adjusting the PEB temperature from 100°C to 140°C resulted in a lower dosage required to remove the resist, while maintaining a large process window (dosage range) where the resist remained soluble. In contrast, Figure 4 and 5 The results showed that increasing the PEB temperature from 100°C to 120°C resulted in a shrinkage of the process window for the resist sample CE1, as well as incomplete development at medium doses.

[0231] Figure 6 Contrast profiles are shown for wafers coated with resist solutions C and CE2, each containing a fluorinated ligand P2, and subjected to PEB at 100°C. Compared to CE2, the coating prepared with resist solution C (i.e., a ternary blend containing the ketal ligand compound K1) exhibits improved positive tonal patterning, with condensation cliffs appearing at higher doses while maintaining a similar transition at lower doses.

[0232] like Figure 7 As demonstrated, the presence of acetal ligands can improve the solubility of exposed photoresist even at higher PEB temperatures. Comparing contrast profiles from wafers coated with resist solution A and subjected to PEB at 100°C or 140°C, it was observed that lower-dose transitions can be reduced by performing PEB at higher temperatures, while also achieving a wider positive hue processing window, for example, by maintaining a high-dose condensation cliff.

[0233] By examining the contrast profiles, the control samples prepared with resist solutions CE1 and CE2 exhibited higher low-dose transitions compared to samples prepared with blends containing organotin compounds K1 with acetal ligands. Under each PEB condition tested, films prepared with resist solutions A, B, and C all showed improved positive tinting process windows compared to CE1 or CE2, with both lower transition doses and higher condensation cliffs. These results demonstrate that photoresist films prepared from blends of organotin precursor compositions and organotin compounds with acetal ligands possess improved positive tinting patterning properties due to the acetal ligands.

[0234] Example 12. Contrast curve showing positive hue improvement as a function of hard baking temperature.

[0235] This embodiment demonstrates the improvement in positive tone patterning and the effect of hard baking on organotin photoresist compositions containing acetal R groups.

[0236] The photoresist solution was prepared from the compounds in Table 6. Compound K1 was synthesized as described in Example 2 above. P3 was synthesized according to the method described in '466 patent as described in Example 10.

[0237] Table 6

[0238]

[0239] Compounds P3 and K1 were blended in a molar ratio of 4:1 and dissolved in an alcohol solvent blend (38 wt% 1-pentanol / 62 wt% 1-propanol) with a total water concentration of 300 ppm to prepare a resist solution (resist solution D) with a total Sn concentration of 0.078 M [Sn].

[0240] A series of photoresist-coated wafers were prepared by spin-coating a photoresist solution D onto a circular 300 mm Si wafer with an approximately 10 nm spin-coated glass (SOG) layer. The coated wafers were then subjected to photoresist plating (PAB) at 100 °C for 60 s. The film thickness of each wafer was measured to be approximately 30 nm using ellipsometry.

[0241] Following PAB, each coated wafer is then exposed on an ASML TwinScan NXE3400 EUV exposure tool to create a contrast array of exposed areas (i.e., pads) on each wafer, wherein each exposed area is subjected to approximately 1 mJ / cm². 2 Approximately 100 mJ / cm 2Different doses of radiation were applied. After EUV exposure, the film was then subjected to PEB at 140°C for 60 seconds. Each wafer was then developed with 2.38 wt% TMAH, followed by rinsing with water to remove residual TMAH. Finally, the wafers were hard-baked (HB) at 100°C, 150°C, 200°C, or 250°C for 60 seconds, or not hard-baked at all.

[0242] After hard baking, the contrast curve was measured and plotted as described in Example 11. Figure 8 The contrast profiles (as a function of HB temperature) of the photoresist film prepared from resist solution D are shown. Only a small change is observed in the contrast profiles when the hard bake temperature is increased to 150°C. In all cases, the exposed film exhibits a contrast ratio below approximately 15 mJ / cm². 2 It is generally insoluble at certain doses, and the condensation cliff is at 60 mJ / cm. 2 The dose was close to that of the target, resulting in approximately 45 mJ / cm. 2 The positive hue process window was observed. For hard baking at 200°C, moderate solubility was observed, with the remaining thickness after development decreasing more rapidly with increasing dose. This effect is attributed to the dose-dependent thermal decomposition of the organic ligands in the photoresist. Comparing the unexposed film thickness (represented by the line to the left of the contrast curve) with the remaining low-dose thickness after development, a small top loss (i.e., the photoresist thickness removed at low doses) was observed for most HB conditions. The more pronounced top loss observed for the 200°C HB condition further confirms the dose-dependent thermal decomposition of the organic ligands. At hard baking at 250°C, the results indicate that the organic ligands in the photoresist were essentially decomposed, as demonstrated by comparing the unexposed film thickness (approximately 23 nm) with the approximately 32 nm unexposed film thickness under lower HB conditions. Figure 8 It was also shown that the 250°C hard baking condition rendered the exposed photoresist material almost completely insoluble in TMAH developer at low doses, as observed by the small top loss and at concentrations below approximately 15 mJ / cm². 2 The near-constant film thickness at different dosages demonstrates this. Hard baking of the photoresist prepared from resist solution D at 250°C has proven to provide good positive tone contrast, very little top loss, and a wide positive tone process window. This example demonstrates the effectiveness of lithography coatings prepared using organotin blends with acetal ligands for positive tone processing.

[0243] Example 13. Contact Hole Patterning

[0244] This embodiment illustrates the patterning of contact holes using positive tone development of a blend of organic-based tin photoresist containing acetal ligands.

[0245] The photoresist solution (resist solution D) described in Example 12 was used to prepare a film capable of EUV patterning. Resist solution D was deposited onto a Si wafer pre-coated with approximately 10 nm SOG by spin coating to obtain a 30 nm thick photoresist coating. The coated wafer was then subjected to PAB at 100°C for 60 seconds. The wafer was then exposed using an ASML TwinScan NXE 3400 exposure tool to form a hexagonal array of holes at a vertical spacing of 38 nm multiplied by a horizontal spacing of 66 nm, with each array printed at different doses at different locations (i.e., fields) on the wafer. The exposed wafer was then subjected to PEB at 140°C for 60 seconds, followed by development using 2.38 wt% TMAH (aqueous solution). Finally, the wafer was baked at 250°C for 1 minute to densify the pattern.

[0246] Then, CD-SEM images were acquired using a commercial CD-SEM instrument and analyzed to determine the values ​​of dose, critical dimension (CD, average diameter of the aperture), and LCDU (local critical dimension uniformity, standard deviation of the average CD) for each acquired image. Figure 9 The image shows a CD-SEM image of a contact hole with a nominal CD of 22 nm. (At 90 mJ / cm²) 2 Contact holes were printed at a dose of [amount missing], and the average CD was measured to be 22.33 nm and the LCDU to be 3.35 nm. The results demonstrate the ability of organotin photoresist blends containing acetal ligands to produce high-resolution contact hole patterns at relatively low doses. The CD and LCDU values ​​are comparable to or lower than those obtained using the additives described in '785 or the double bake-double develop method.

[0247] The above embodiments are intended to be illustrative rather than restrictive. Other embodiments are also within the scope of the claims. Furthermore, although the invention has been described with reference to specific embodiments, those skilled in the art will recognize that changes in form and detail may be made without departing from the spirit and scope of the invention. Any inclusion of the above document by reference is limited to subject matter contrary to the explicit disclosure herein. With regard to the specific structures, compositions, and / or processes described herein using components, elements, ingredients, or other divisions, it should be understood that, unless expressly stated otherwise, the disclosure herein covers specific embodiments, embodiments comprising specific components, elements, ingredients, other divisions, or combinations thereof, and embodiments consisting primarily of such specific components, ingredients, or other divisions, or combinations thereof, which may include additional features that do not alter the essential nature of the subject matter, as indicated in the discussion. Unless expressly stated otherwise, the term “about” is used herein to refer to the measurement error of a particular parameter.

Claims

1. A type of (OR) 4 (OR) 3 )R 2 CR 1 The composition of SnL3, wherein R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 It is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms, wherein R 3 and R 4 Independently a substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, or wherein R3 and R4 together form a bridging structure -OR 5 O- (R 5 = R 3 + R 4 ), where R 5 It is a hydrocarbon group with 1 to 10 carbon atoms and forms a ring bond between the O atoms of the acetal, and L is a hydrolyzable ligand.

2. The composition according to claim 1, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 A hydrocarbon group having one or two carbon atoms, either substituted or unsubstituted.

3. The composition according to claim 1, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 It is hydrogen.

4. The composition according to any one of claims 1-3, wherein R 2 It is an unsaturated hydrocarbon group.

5. The composition according to any one of claims 1-4, wherein R 3 and R 4 A hydrocarbon group, whether substituted or unsubstituted, having one or two carbon atoms.

6. The composition according to any one of claims 1-4, wherein R 3 and R 4 Forming a bridge structure, and R 5 It is an unbranched substituted or unsubstituted hydrocarbon group with 2-4 carbon atoms.

7. The composition according to any one of claims 1-6, wherein L is alkoxy, dialkylamino, alkylynyl, alkylsilylamino, or a combination thereof.

8. The composition according to any one of claims 1-6, wherein L is derived from -OR b It means that R b It is a hydrocarbon group having 1 to 15 carbon atoms.

9. The composition according to any one of claims 1-6, wherein L is tert-butoxy or tert-pentoxy.

10. The composition according to any one of claims 1-9, wherein R 3 R 4 R 3 and R 4 Both, or R 5 It contains I or F groups.

11. The composition according to any one of claims 1-10, wherein R 5 Including aromatic groups.

12. The composition according to claim 11, wherein the aromatic group is iodinated.

13. The composition according to claim 11, wherein the aromatic group is fluorinated.

14. The composition according to claim 11, wherein the aromatic group has a -CF3 functional group.

15. The composition of claim 14, wherein the aromatic group has two -CF3 functional groups bonded to adjacent carbon atoms.

16. A blend composition comprising the composition of any one of claims 1-15 and a compound of formula (R a SnL'3 represents an organotin-based composition or a combination thereof, wherein R a L is a substituted or unsubstituted hydrocarbon ligand having 1 to 30 carbon atoms and a Sn-C bond, and L' is a hydrolyzable ligand that is the same as or different from L.

17. The blend composition according to claim 16, wherein R a Including cyclic alkyl groups, aromatic groups, fluorinated groups, unbranched alkyl groups, branched alkyl groups, or combinations thereof.

18. The blend composition according to claim 16 or claim 17, wherein L, L', or both are alkoxy ligands.

19. The blend composition according to any one of claims 16-18, wherein R a This includes tertiary carbons bonded to Sn.

20. A precursor solution comprising a solvent and a composition of any one of claims 1-19 dissolved in the solvent.

21. The precursor solution according to claim 20, wherein the solvent is an alcohol.

22. The precursor solution according to claim 20 or claim 21, wherein the tin concentration of the solution is from about 0.005 M to about 1 M.

23. A coating substrate, the coating substrate comprising: Base, and An organotin coating on the surface of the substrate; The organotin coating described herein comprises an oxo-hydroxyl network, which is incorporating a compound of the formula (OR) 4 (OR) 3 )R 2 CR 1 Sn represents the organotin group, where R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently substituted or unsubstituted hydrocarbon groups having 1 to 4 carbon atoms, or together forming a bridging structure -OR 5 O- (R 5 = R 3 + R 4 ), where R 5 It consists of a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal.

24. The coating substrate of claim 23, wherein the substrate comprises a semiconductor wafer.

25. The coating substrate according to claim 23 or claim 24, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 A hydrocarbon group having one or two carbon atoms, either substituted or unsubstituted.

26. The coating substrate according to claim 23 or claim 24, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 It is hydrogen.

27. The coating substrate according to any one of claims 23-26, wherein R 2 It is an unsaturated hydrocarbon group.

28. The coating substrate according to any one of claims 23-27, wherein R 3 and R 4 A hydrocarbon group, whether substituted or unsubstituted, having one or two carbon atoms.

29. The coating substrate according to any one of claims 23-27, wherein R 3 and R 4 Forming a bridge structure, and R 5 It is an unbranched substituted or unsubstituted hydrocarbon group with 2-4 carbon atoms.

30. The coating substrate according to any one of claims 23-29, wherein the oxo-hydroxy network is further incorporated by formula R a Sn represents the part where R a A substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms that forms a C-Sn bond.

31. The coating substrate according to claim 30, wherein R a It does not contain acetal groups or benzodioxane groups.

32. The coating substrate according to claim 30 or 31, wherein the thickness of the coating substrate is from about 2 nm to about 40 nm.

33. The coating substrate according to any one of claims 30-32, wherein about 2 mol% to about 50 mol% of the C-Sn bond is bonded to (OR) 4 (OR) 3 )R 2 CR 1 The Sn part corresponds to this.

34. The coating substrate according to any one of claims 30-32, wherein about 10 mol% to about 40 mol% of the C-Sn bond is bonded to (OR) 4 (OR) 3 )R 2 CR 1 The Sn part corresponds to this.

35. The coating substrate according to any one of claims 30-34, wherein the coating is insoluble in a 2.38% by weight aqueous solution of tetramethylammonium hydroxide.

36. The coating substrate according to any one of claims 30-35, wherein R a Including cyclic alkyl groups, aromatic groups, fluorinated groups, unbranched alkyl groups, branched alkyl groups, or combinations thereof.

37. The coating substrate according to any one of claims 23-36, wherein the coating substrate is formed from a precursor solution, the precursor solution comprising: Organic solvents, By formula (OR) 4 (OR) 3 )R 2 CR 1 SnL3 represents the first tin precursor composition, wherein R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR 5 O- (R 5 = R 3 + R 4 ), where R 5 It is a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, and L is a hydrolyzable ligand, and From formula R a SnL'3 represents the second tin precursor composition, wherein R a L is a substituted or unsubstituted hydrocarbon ligand having 1 to 30 carbon atoms and a Sn-C bond, and L' is a hydrolyzable ligand that is the same as or different from L.

38. The coating substrate according to any one of claims 23-37, wherein the average thickness of the organotin coating is from about 1 nm to about 50 nm.

39. The coating substrate of claim 38, wherein the thickness variation of the organotin coating is no more than 25% relative to the average thickness.

40. The coating substrate according to any one of claims 23-39, wherein the Sn-C bond is radiation-sensitive.

41. The coating substrate according to any one of claims 23-40, wherein the coating remains soluble in at least some polar solvents after being applied and baked.

42. The coating substrate according to any one of claims 23-41, wherein the coating is sensitive to EUV radiation.

43. A precursor solution for depositing a patterned composition, the precursor solution comprising: Organic solvents, By formula (OR) 4 (OR) 3 )R 2 CR 1 SnL3 represents the first tin precursor composition, wherein R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR 5 O- (R 5 = R 3 + R 4 ), where R 5 It is a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, and L is a hydrolyzable ligand, and From formula R a SnL'3 represents the second tin precursor composition, R a It is a substituted or unsubstituted hydrocarbon ligand having 1 to 30 carbon atoms, and L' is a hydrolyzable ligand that is the same as or different from L.

44. The precursor solution according to claim 43, wherein the organic solvent comprises alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, esters, ketones, or combinations thereof.

45. The precursor solution according to claim 43, wherein the organic solvent comprises 4-methyl-2-pentanol, 1-propanol, 1-pentanol, 1-butanol, methanol, isopropanol, toluene, THF, PGMEA, or combinations thereof.

46. ​​The precursor solution according to any one of claims 43-45, wherein the molar concentration of tin is from about 0.005 M to about 1.4 M.

47. The precursor solution according to any one of claims 43-46, wherein the organic solvent comprises a controlled amount of water.

48. The precursor solution according to any one of claims 43-47, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 A hydrocarbon group having one or two carbon atoms, either substituted or unsubstituted.

49. The precursor solution according to any one of claims 43-47, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 It is hydrogen.

50. The precursor solution according to any one of claims 43-49, wherein R 2 It is an unsaturated hydrocarbon group.

51. The precursor solution according to any one of claims 43-50, wherein R 3 and R 4 A hydrocarbon group, whether substituted or unsubstituted, having one or two carbon atoms.

52. The precursor solution according to any one of claims 43-50, wherein R 3 and R 4 Forming a bridge structure, and R 5 It is an unbranched substituted or unsubstituted hydrocarbon group with 2-4 carbon atoms.

53. The precursor solution according to any one of claims 43-52, wherein R a Including cyclic alkyl groups, aromatic groups, fluorinated groups, unbranched alkyl groups, branched alkyl groups, or combinations thereof.

54. The precursor solution according to any one of claims 43-53, wherein R a R 3 R 4 R 5 Or combinations thereof contain I or F groups.

55. The precursor solution according to any one of claims 42-54, wherein R a Or R 5 Both may include aromatic groups.

56. The precursor solution according to claim 55, wherein the aromatic group is iodinated or fluorinated.

57. The precursor solution according to any one of claims 42-56, wherein L and / or L' are independently alkoxy, dialkylamino, alkylynyl, alkylsilylamino, or combinations thereof.

58. The precursor solution according to any one of claims 43-57, wherein L and / or L' are tert-butoxy or tert-pentoxy.

59. The precursor solution according to any one of claims 43-57, wherein L and L' are alkoxy ligands.

60. The precursor solution according to any one of claims 42-59, wherein the precursor solution comprises about 2 mol% to about 50 mol% of the first tin precursor composition, expressed as a percentage of total tin content.

61. The precursor solution according to claim 59, wherein the deposit formed from the precursor solution under hydrolysis conditions is substantially insoluble in a 2.38 wt% aqueous solution of tetramethylammonium hydroxide after solvent removal.

62. A method for patterning a coated substrate having a virtual image formed using patterned EUV radiation, the coated substrate comprising a substrate and an organotin coating on a surface of the substrate, the organotin coating comprising unirradiated portions and irradiated portions. The unirradiated portion comprises a patternable composition comprising an oxo-hydroxyl network, the oxo-hydroxyl network being bound to a group of elements of the formula (OR) 4 (OR) 3 )R 2 CR 1 Sn represents the organotin group, where R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR 5 O- (R 5 =R 3 + R 4 ), where R 5 The method comprises a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, the method comprising: The coating on the surface of the substrate is brought into contact with an aqueous liquid to substantially remove the irradiated portion while leaving the unirradiated portion substantially intact.

63. The method of claim 62, wherein the aqueous liquid comprises tetramethylammonium hydroxide.

64. The method of claim 62 or claim 63, wherein the contact is performed using a water puddle immersion method.

65. The method of claim 62 or claim 63, wherein the contact is performed using spin coating.

66. The method of claim 65, wherein the substrate is cleaned with an inert liquid after a selected time period following spin coating.

67. The method according to any one of claims 62-66, wherein after the irradiated portion is removed, a physical pattern is formed to expose a region of the substrate surface.

68. The method of claim 67, wherein the exposed area is a regular pattern of holes.

69. The method according to claim 67 or claim 68, further comprising: After the physical pattern is formed, the coating substrate is heated in a hard bake at a temperature of at least about 175°C for at least about 15 seconds.

70. A method for patterning a coated substrate having a virtual image formed using patterned EUV radiation, the coated substrate comprising a substrate and an organotin coating on a surface of the substrate, the organotin coating comprising unirradiated portions and irradiated portions. The unirradiated portion comprises a patternable composition comprising an oxo-hydroxyl network, the oxo-hydroxyl network being bound to a group of elements of the formula (OR) 4 (OR) 3 )R 2 CR 1 Sn represents the organotin group, where R 1 R is a substituted or unsubstituted hydrocarbon group having 1 to 15 carbon atoms and a Sn-C bond. 2 R is a hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. 3 and R 4 Independently, it can be a hydrocarbon group with 1 to 4 carbon atoms or together to form a bridging structure - OR 5 O- (R 5 =R 3 + R 4 ), where R 5 The method comprises a hydrocarbon group having 1 to 10 carbon atoms and forming a ring bond between the O atoms of the acetal, the method comprising: The coating on the surface of the substrate is brought into contact with an organic liquid to substantially remove the unirradiated portion while keeping the irradiated portion substantially intact.

71. The method of claim 70, wherein the organic liquid comprises ketones, esters, glycol ethers, carboxylic acids, quaternary ammonium salts, alcohols, or combinations thereof.

72. The method of claim 70, wherein the organic liquid comprises 2-heptanone, toluene, PGMEA, acetic acid, or combinations thereof.

73. The method according to any one of claims 70-72, further comprising rinsing with an aqueous liquid after the contact step.

74. The method according to any one of claims 70-73, wherein the organic liquid further comprises water.

75. A method for synthesizing substituted 1,3-benzodioxane compounds, the method comprising: The catechol in the organic solvent reacts with hexamethylsilazane to form an intermediate; as well as The intermediate in an organic solvent is reacted with a ketone or aldehyde in the presence of a trimethylsilyl trifluoromethanesulfonate catalyst to form a substituted 1,3-benzodioxane.

76. The method of claim 75, wherein the catechol is iodinated or fluorinated.

77. The method according to claim 75 or claim 76, wherein the organic solvent comprises toluene.

78. The method according to any one of claims 75-77, wherein the ketone or aldehyde has a chlorine functional group.

79. The method according to any one of claims 75-77, wherein the aldehyde or ketone is of formula R 1 COR 2 It means that R 1 R is a hydrocarbon group with 1 to 15 carbon atoms, either substituted or unsubstituted. 2 It is a hydrogen (aldehyde) or a substituted or unsubstituted hydrocarbon group (ketone) having 1 to 10 carbon atoms.

80. The method of claim 75, wherein R 1 It contains halogen groups.

81. The method of claim 80, wherein the halogen group is a terminal methyl chloride group.

82. The method according to any one of claims 79-81, further comprising: The substituted 1,3-benzodioxane is reacted with an alkali metal tin trialkyl oxide to form a substituted 1,3-benzodioxane tin trialkoxy group.

83. The method of claim 82, wherein the alkali metal tin trioxide comprises potassium tin trimektoxy.

84. A method based on formula C6R a R b R c R d O2CR 1 R 2 The compound represented is a halogen-substituted 2-alkyl-1,3-benzodioxane with optional other substitutions, wherein R 1 R is a hydrocarbon group with 1 to 15 carbon atoms, either substituted or unsubstituted. 2 It is a hydrocarbon group consisting of hydrogen or substituted or unsubstituted hydrocarbons having 1 to 10 carbon atoms.

85. The compound according to claim 84, wherein the halogen is I or F.

86. The composition according to claim 84 or claim 85, wherein R 1 A substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R 2 A hydrocarbon group having one or two carbon atoms, either substituted or unsubstituted.

87. The composition according to any one of claims 84-86, wherein R 1 It contains halogen groups.

88. The compound according to claim 87, wherein the halogen group is a terminal chlorine atom.

89. The compound according to claim 87 or claim 88, wherein the terminal carbon halide is unsaturated.

90. The composition according to any one of claims 84-89, wherein R 1 It contains Sn-C bonds.

91. The composition according to claim 90, wherein R 1 It contains a trialkoxytin group.

92. The compound according to claim 84, wherein the compound comprises 4-chloro-1-methyl(4,5-diiodo)benzodioxane or 4-chloro-1-methyl(4,5-di(trifluoromethyl))benzodioxane.

93. The compound according to claim 84, wherein the compound comprises 2-(1-methyl-3-propyltin tri(tert-butyloxy))1,3-(3-fluorobenzo)dioxane; 4-((4,5-diiodo)benzodioxane)-pentyltin tri(tert-butyloxy); or 4-((4,5-di(trifluoromethyl))benzodioxane)-pentyltin tri(tert-butyloxy).

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