A method for preparing cyclopentadienyl tantalum metal precursor
Through the improved preparation method of cyclopentadienyl tantalum metal precursor, the problems of low efficiency and insufficient purity in the prior art are solved, and the preparation of high-purity and high yield precursors is realized, and its application in semiconductor devices is expanded.
Patent Information
- Application Number
- CN202411979269.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-04-01
AI Technical Summary
The existing preparation methods of cyclopentadienyl tantalum metal precursors are inefficient and have insufficient product yield and purity, resulting in limited application in semiconductor device manufacturing and difficult to remove by-products in one-pot synthesis.
An intermediate 1 is prepared by a cyclopentadienyl tantalum metal precursor by mixing and reacting the tantalum metal source, primary amine and active substance, and then reacting with an amine metal with M1 (NR2R3)x structure, and finally adding cyclopentadiene to combine specific active substances and process parameters to avoid the occurrence of side reactions and improve product purity and yield.
The large-scale preparation of cyclopentadienyl-based tantalum metal precursor has been achieved, with the product purity reaching more than 99.5% and the metal purity is 6N or above. It is suitable for semiconductor thin film deposition, improving production efficiency and economic value.
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Figure CN119735618A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of electronic chemical manufacturing, and in particular relates to a method for preparing a cyclopentadienyl tantalum-based metal precursor. Background Art
[0002] Tantalum-containing metal films have been widely used in semiconductor manufacturing. For example, tantalum-containing metal oxide films with high dielectric constants can be used as high dielectric layers of DRAM chips, and tantalum-containing metal nitride films can be used as conductive layers in 3D NAND structures, diffusion-proof layers between metal interconnects and low dielectric constant materials, and electron transport layers or passivation layers in solar cells, etc. Although tantalum-containing metal films have many excellent properties, there are very few tantalum-based precursors that can be used in the ALD process. As semiconductor technology continues to move toward smaller process nodes, higher precision and complexity, higher requirements are placed on the chemical and physical properties of tantalum-based metal precursors.
[0003] Cyclopentadienyl tantalum metal precursors do not have the halogen residues in halide-based precursors that cause corrosion damage to the deposition chamber, and a series of problems that solid-state aminated precursors easily lead to the failure of deposition devices. At this stage, they can be used as the preferred precursor for vapor-deposited tantalum thin films in some semiconductor device manufacturing. The current preparation method of cyclopentadienyl tantalum metal precursors is generally to first react a metal chloride source, a primary amine, and an organic base such as tert-butyl lithium and decompress and distill out an intermediate-amidated metal complex, and then react it with a cyclopentadiene monomer to purify the product. In order to improve the reaction yield and product purity, the step of decompressing and distilling out the intermediate is indispensable, but the above-mentioned intermediates are basically solid, and the purification difficulty of the decompressed distillation intermediate is large and time-consuming, which seriously affects the preparation efficiency of the cyclopentadienyl metal precursor.
[0004] There are reports in the industry that a one-pot synthesis route is used to prepare cyclopentadienyl tantalum metal precursors. However, the inventors have found through extensive research that when the conventional technical route is used in combination with the one-pot method, 5-10% of by-products will appear in the product. Even through multiple distillation purifications, it is difficult to remove the by-products, which seriously affects the purity of the product (≤99%) and causes the product to lose its industrial application value. Summary of the invention
[0005] In view of the shortcomings of the prior art, the present invention provides a method for preparing a cyclopentadienyl tantalum-based metal precursor; the preparation method can solve the problems of low preparation efficiency, low product yield and low purity in the prior art, realize the large-scale preparation of cyclopentadienyl tantalum-based metal precursors, and expand their application range in semiconductor devices.
[0006] Based on the above problems, the present invention adopts the following technical solutions:
[0007] First, the present invention provides a method for preparing a cyclopentadienyl tantalum-based metal precursor, comprising the following steps:
[0008] (1) at least a tantalum metal source, a primary amine having an R1NH2 structure, and an active material having an NR'R"2 structure are mixed and reacted to prepare an intermediate 1;
[0009] (2) At least intermediate 1 and M1(NR2R3) x The structure of the amine metal reaction to prepare intermediate 2;
[0010] (3) Add cyclopentadiene to the intermediate 2 to obtain a cyclopentadienyl tantalum-based metal precursor product.
[0011] Furthermore, the cyclopentadienyl tantalum-based metal precursor has a structure of Formula 1: (Formula 1);
[0012] Wherein, M is a tantalum metal selected from vanadium (V), niobium (Nb), and tantalum (Ta); R is any one of H, a C1-C6 alkyl group, a C1-C6 alkoxy group, a silane group, a substituted amine group, and an alkylamide group; and n is an integer of 0-5.
[0013] Furthermore, in the cyclopentadienyl tantalum metal precursor, R1 is a C1-C5 alkyl group, which can be any one of a C1 alkyl group, a C2 alkyl group, a C3 alkyl group, a C4 alkyl group, and a C5 alkyl group; R1 is preferably any one of a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group, an isopentyl group, and a neopentyl group.
[0014] Preferably, R1 is a C1-C4 alkyl group, selected from any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl and tert-butyl.
[0015] Furthermore, in the cyclopentadienyl tantalum metal precursor, R2 and R3 are independently selected from any one of substituted or unsubstituted C1-C8 alkyl groups, wherein the substituents include but are not limited to at least one of alkoxy, alkylamino, ester, and alkylamide.
[0016] Furthermore, R2 and R3 are independently selected from unsubstituted C1-C8 alkyl groups, and are further preferably selected from any one of methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, cyclohexyl, heptyl and octyl.
[0017] In one embodiment, said R2 and R3 are independently selected from C1-C3 alkyl groups.
[0018] Furthermore, the tantalum metal source includes tantalum metal halide and / or tantalum metal oxyhalide. When the tantalum metal is vanadium, the tantalum metal source is tantalum metal oxyhalide. When the tantalum metal source is niobium or tantalum, the tantalum metal source is tantalum metal halide.
[0019] Preferably, the tantalum metal halide is selected from at least one of chloride, bromide and iodide.
[0020] Preferably, the tantalum-based metal oxyhalide is oxychloride.
[0021] Furthermore, R1 in the primary amine, R2 and R3 in the secondary amine are the same as R1, R2 and R3 in the cyclopentadienyl tantalum-based metal precursor.
[0022] Furthermore, in the active substance, R' and R" are independently selected from C1-C5 alkyl groups, preferably, R' and R" are independently selected from any one of methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, isopentyl and neopentyl.
[0023] Preferably, the active substance is selected from at least one of triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, tri-n-pentylamine, dimethylethylamine, dimethylpropylamine, dimethylbutylamine, diethylmethylamine, diethylpropylamine and dimethylbutylamine.
[0024] Further, the molar ratio of the tantalum metal source, the primary amine and the active substance is 1:1-2:1-3, and exemplary are 1:1:1, 1:1.3:1, 1:1:1.5, 1:1:2, 1:1:3, 1:1.5:1, 1:2:1, 1:1.5:1.5, 1:1.5:2, 1:1.5:2, 1:1.5:2.5, 1:1.5:3, 1:1.6:3, 1:2:3, 1:2:1, 1:2:1.5, 1:2:2, 1:2:2.5, etc.
[0025] Preferably, the molar ratio of the tantalum metal source, the primary amine and the active material is 1:1-1.6:2-3.
[0026] Preferably, the reaction in step (1) is carried out in a first organic solvent, wherein the first organic solvent includes but is not limited to at least one of n-butane, n-pentane, n-hexane, n-heptane, n-octane, toluene, xylene, carbon tetrachloride, dimethyl ether (DME), tetrahydrofuran (THF), and diethyl ether.
[0027] Preferably, the first organic solvent comprises dimethyl ether.
[0028] Furthermore, in step (1), the mass concentration of the tantalum metal source is 30-600 g / L, preferably 50-300 g / L, such as 30 g / L, 40 g / L, 50 g / L, 60 g / L, 70 g / L, 80 g / L, 90 g / L, 100 g / L, 120 g / L, 130 g / L, 140 g / L, 145 g / L, 150 g / L, 180 g / L, 200 g / L, 215 g / L, 220 g / L, 250 g / L, 270 g / L, 300 g / L, etc.
[0029] Further, the M1(NR2R3) x In the amine metal of the structure, M1 is selected from Li, Na, K, Mg, Ca, Sr, and x is the valence of M1; specifically, when M1 is Li, Na or K, x is 1; when M1 is Mg, Ca, Sr, x is 2.
[0030] Preferably, M1 is Li or Na, and x is 1.
[0031] Furthermore, the molar ratio of the tantalum metal source to the amine metal is 1:2.5-5, such as 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, and 1:2.0.
[0032] Preferably, the molar ratio of the tantalum metal source to the amine metal is 1:3.0-3.7.
[0033] Furthermore, the present invention does not have M1(NR2R3) in step (2). x The addition form of the amine metal of the structure is strictly limited, and it can be directly added using M1 (NR2R3) x The amine metal itself can also be indirectly obtained by adding a hydrocarbon metal M1Y and a secondary amine HNR2R3 to react with M1(NR2R3) x Amine metal of the structure; Y in M1Y is an alkyl, alkenyl or alkynyl group.
[0034] In one embodiment, step (2) is to add at least intermediate 1 to a mixture having M1(NR2R3) x The structure of the amine metal itself is reacted to prepare intermediate 2.
[0035] In one embodiment, step (2) is to add at least intermediate 1 to a reaction mixture of alkylated metal M1Y and secondary amine HNR2R3 to prepare intermediate 2 after reaction.
[0036] Furthermore, Y is at least one of a C1-C5 alkyl group, a C2-C5 alkenyl group, a C2-C4 alkynyl group, and a phenyl group.
[0037] Preferably, the alkylated metal M1Y includes but is not limited to at least one of methyl lithium, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, phenyl lithium, methylphenyl lithium, vinyl lithium, acetylide lithium, acetylide sodium, methyl sodium, ethyl sodium, n-propyl sodium, isopropyl sodium, n-butyl sodium, sec-butyl sodium, tert-butyl sodium, phenyl sodium, methylphenyl sodium, sodium acetylide, disodium acetylide, sodium butylide, n-butyl potassium, sec-butyl potassium, tert-butyl potassium, amyl potassium, diethyl magnesium, and dibutyl magnesium.
[0038] Preferably, the molar ratio of the tantalum metal source to the hydrocarbon-based metal is 1:0.5-5, such as 1:0.5, 1:0.7, 1:1, 1:1.3, 1:1.5, 1:1.8, 1:2, 1:2.3, 1:2.5, 1:2.7, 1:3, 1:3.2, 1:3.4, 1:3.5, 1.3.7, 1:4, 1:4.3, 1:4.5, 1:5, 1:5.2, 1:5.5, 1:5.8, 1:6, 1:6.2, 1:6.5, 1:6.7, 1:7, etc.; more preferably, it is 1:2.5-5, and more preferably, it is 1:3.0-4.0.
[0039] Preferably, the molar ratio of the tantalum metal source to the secondary amine is 1:0.8-5, such as 1:0.8, 1:1.1, 1:1.2, 1:1.5, 1:1.7, 1:2, 1:2.3, 1:2.5, 1:2.7, 1:3, 1:3.2, 1:3.4, 1:3.5, 1.3.7, 1:4, 1:4.3, 1:4.5, 1:5, 1:5.2, 1:5.5, 1:5.8, 1:6, 1:6.2, 1:6.5, 1:6.7, 1:7, etc.; further preferably, it is 1:2.5-5, and more preferably, it is 1:3.0-4.0.
[0040] Preferably, the temperature for the mixed reaction of the alkylated metal and the secondary amine is 10-30° C., preferably 20-26° C.; the mixed reaction time is 0.5-6 h, preferably 1-4 h.
[0041] Preferably, the reaction mixture of the alkylated metal M1Y and the secondary amine HNR2R3 further comprises a second organic solvent, and the second organic solvent includes but is not limited to at least one of an alkane solvent, an aromatic hydrocarbon solvent, and an ether solvent.
[0042] Preferably, the alkane solvent is a C1-C12 alkane, including but not limited to at least one of ethane, propane, butane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, cyclohexane, and cyclooctane. The aromatic hydrocarbon solvent includes but is not limited to at least one of benzene, toluene, xylene, and trimethylbenzene. The ether solvent includes but is not limited to at least one of diethyl ether, dipropyl ether, diisopropyl ether, ethyl butyl ether, dibutyl ether, dipentyl ether, and dihexyl ether.
[0043] Preferably, the mass concentration of the alkylated metal in the reaction mixture is 5-120 g / L, exemplified by 5 g / L, 10 g / L, 20 g / L, 30 g / L, 40 g / L, 45 g / L, 50 g / L, 55 g / L, 60 g / L, 65 g / L, 70 g / L, 73 g / L, 75 g / L, 80 g / L, 85 g / L, 86 g / L, 90 g / L, 95 g / L, 97 g / L, 100 g / L, 105 g / L, 110 g / L, 115 g / L, 120 g / L, etc.
[0044] Preferably, the cyclopentadiene in step (3) is a substituted or unsubstituted cyclopentadiene with the structural formula Cp(R)n; R and n are as defined above.
[0045] Preferably, the molar ratio of the tantalum metal source to cyclopentadiene is 1:0.8-3, such as 1:0.8, 1:0.9, 1:1.0, 1:1.2, 1:1.5, 1:1.7, 1:1.9, 1:2.0, 1:2.2, 1:2.5, 1:2.7, 1:3.0; more preferably 1:1-1.5.
[0046] Preferably, the reaction temperature of steps (1)-(2) is below 0°C, more preferably below -5°C, and more preferably below -10°C. The optional temperatures include: -10°C, -11°C, -12°C, -13°C, -14°C, -15°C, -16°C, -17°C, -18°C, -19°C, -20°C, -22°C, -25°C, -28°C, -30°C, etc.
[0047] In one embodiment, the reaction temperature of steps (1)-(2) is -10°C to -20°C.
[0048] Preferably, the reaction time of step (2) is 5-48 h, more preferably 10-24 h.
[0049] Preferably, the reaction temperature of step (3) is 5-35°C, more preferably 15-28°C, and optionally 15°C, 18°C, 20°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C.
[0050] Preferably, the reaction time of step (3) is 0.5-10 h, more preferably 1-5 h.
[0051] Preferably, the preparation method further comprises the step of purifying the cyclopentadienyl tantalum-based metal precursor product, and the purification method includes but is not limited to at least one of filtration, adsorption, distillation, extraction, and column chromatography.
[0052] Secondly, the present invention also provides a cyclopentadienyl tantalum metal precursor prepared according to the method, wherein the precursor has a structure shown in the following formula 1: (Formula 1);
[0053] wherein M, R, R1-R3, and n are as defined above.
[0054] In some embodiments, the cyclopentadienyl tantalum metal precursor includes but is not limited to any one of tert-butyliminobis(dimethylamino)cyclopentadienyl niobium, tert-butyliminobis(diethylamino)cyclopentadienyl niobium, n-butyliminobis(dimethylamino)cyclopentadienyl niobium, n-butyliminobis(diethylamino)cyclopentadienyl niobium, isopropyliminobis(dimethylamino)cyclopentadienyl niobium, and isopropyliminobis(diethylamino)cyclopentadienyl niobium.
[0055] In some embodiments, the cyclopentadienyl tantalum metal precursor includes but is not limited to any one of tert-butyliminobis(dimethylamino)cyclopentadienyl vanadium, tert-butyliminobis(diethylamino)cyclopentadienyl vanadium, n-butyliminobis(dimethylamino)cyclopentadienyl vanadium, n-butyliminobis(diethylamino)cyclopentadienyl vanadium, isopropyliminobis(dimethylamino)cyclopentadienyl vanadium, and isopropyliminobis(diethylamino)cyclopentadienyl vanadium.
[0056] In some embodiments, the cyclopentadienyl tantalum-based metal precursor includes but is not limited to any one of tert-butyliminobis(dimethylamino)cyclopentadienyl tantalum, tert-butyliminobis(diethylamino)cyclopentadienyl tantalum, n-butyliminobis(dimethylamino)cyclopentadienyl tantalum, n-butyliminobis(diethylamino)cyclopentadienyl tantalum, isopropyliminobis(dimethylamino)cyclopentadienyl tantalum, and isopropyliminobis(diethylamino)cyclopentadienyl tantalum.
[0057] Preferably, the precursor includes ≤10% by mole percentage of the substance represented by formula 2: (Formula 2);
[0058] wherein M, R, R1-R3, and n are as defined above.
[0059] Preferably, the precursor includes ≤5% by mole percentage of the substance represented by Formula 2; more preferably, it includes ≤3% by mole percentage of the substance represented by Formula 2; and more preferably, it does not contain the substance represented by Formula 2.
[0060] Furthermore, the precursor is used to prepare a semiconductor thin film; the semiconductor thin film can be deposited on a planar or non-planar substrate by at least one of ALD, CVD, PEALD, PECVD, PVD, cyclic CVD, etc.
[0061] The present invention creatively proposes a problem not found in the prior art, that is, in the process of synthesizing cyclopentadienyl tantalum metal precursor products by one-pot method, impurities of formula 2 will appear and affect the purity of the product. The inventors found in the process of studying the one-pot process that the addition of cyclopentadiene to the aforementioned reaction solution may affect the physical properties of intermediate 2, such as reducing its boiling point, etc., thereby causing the primary amine of the R1NH2 structure present in the reaction solution to attack the reaction site of intermediate 2, resulting in the generation of impurities of formula 2 and reducing the purity of the product. In conventional processes, in order to obtain higher yield and purity, each step of the operation has a step of distilling out the intermediate, and the impurity will not be generated in the reaction involving only the intermediate and cyclopentadiene. The present invention solves the creative problem proposed by combining the use of specific active substances in the one-pot process, which may be due to the special coordination effect between the active substance and the intermediate to avoid the occurrence of side reactions; the amount of active substance and other process parameters are further specified to make the yield and purity of the product better.
[0062] Beneficial effects of the present invention:
[0063] (1) The present invention creatively proposes the technical problems existing in the one-pot process, and uses specific active substances in combination in the process. The conditions such as the amount of active substances and reaction parameters are specified to avoid the generation of impurities that are difficult to separate in the product. The crude product has good nuclear magnetic purity. Through simple distillation and other purification operations, a product with a component purity of more than 99.5% and a metal purity of 6N or above can be obtained. The product can be used as a tantalum metal source in the semiconductor thin film deposition process.
[0064] (2) The one-pot synthesis process of the present invention can effectively shorten the synthesis time of cyclopentadienyl tantalum metal precursor products, improve production efficiency and yield of the synthesis route, and has high economic value. BRIEF DESCRIPTION OF THE DRAWINGS
[0065] Figure 1 : The product after the precursor distillation prepared in Example 1 1 H NMR characterization spectrum;
[0066] Figure 2 : The product after the precursor distillation prepared in Comparative Example 11 H NMR characterization spectrum;
[0067] Figure 3 : The product after the precursor distillation prepared in Comparative Example 6 1 H NMR characterization spectrum. DETAILED DESCRIPTION
[0068] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0069] Example 1
[0070] This embodiment provides a method for preparing a cyclopentadienyl tantalum-based metal precursor, wherein the structure of the precursor is: ;
[0071] The preparation method comprises the following steps:
[0072] S1. In a glove box, weigh 7L of DME and add it to a reaction bottle, stir magnetically; cool the reaction bottle to -10°C under the protection of high-purity nitrogen, and slowly add 1000g of NbCl5; maintain the temperature at -10°C and slowly drop 749g of triethylamine into the reaction bottle, and then continue to drop 275g of tert-butylamine, filter through a G3 funnel, wash the filter cake three times with 500mL of DME, combine the filtrate, and prepare intermediate 1.
[0073] S2. Take another three-necked round-bottom flask and replace the nitrogen in it, add 805.8 g of n-butyl lithium and 11 L of n-hexane, cool to -30°C, introduce 567 g of dimethylamine, and react at 25±3°C for 2 h to obtain a reaction solution containing amine metal.
[0074] S3. Slowly drip the filtrate of S1 into the reaction solution of S2, control the temperature of the reaction solution to -10°C, and after dripping, react overnight at 25±3°C for 12 hours to prepare intermediate 2.
[0075] S4. The reaction solution of S3 was temperature controlled at 0°C, and 283 g of cyclopentadiene was slowly added dropwise. After the addition was completed, the mixture was stirred at 25±3°C for two hours, and then the solvent was removed at 110°C and normal pressure. 872 g of crude product was distilled off under reduced pressure. The yield of the product was 74.3%, and the HNMR purity was 89.5%.
[0076] The precursor after distillation 1H NMR (400MHz, C6D6) characterization data: δ5.98 (s, 5H), 3.21 (s, 12H), 1.22 (s, 9H), characterization spectrum is attached Figure 1 , the above not only confirms the structure of the prepared precursor, but also verifies that the product prepared by this method does not contain impurities with the following structures: .
[0077] Example 2
[0078] This embodiment provides a method for preparing a cyclopentadienyl tantalum-based metal precursor, wherein the structure of the precursor is:
[0079] The preparation method comprises the following steps:
[0080] S1. In a glove box, weigh 700 mL of DME and add it to a reaction bottle, stir magnetically; under the protection of high-purity nitrogen, cool the reaction bottle to -10°C and slowly add 150 g of NbCl5; maintain the temperature at -10°C and slowly drop 56.2 g of triethylamine into the reaction bottle, then continue to drop 53.0 g of tert-butylamine, filter through a G3 funnel, wash the filter cake three times with 50 mL of DME, combine the filtrates, and prepare intermediate 1.
[0081] S2. Take another three-necked round-bottom flask and replace the nitrogen in it, add 107.6 g of n-butyl lithium and 1.1 L of n-hexane, cool to -30°C, introduce 75.6 g of dimethylamine, and react at 25±3°C for 2 h to obtain a reaction solution containing amine metal.
[0082] S3. Slowly drip the filtrate of S1 into the reaction solution of S2, control the temperature of the reaction solution to -10°C, and after dripping, react overnight at 25±3°C for 12 hours to prepare intermediate 2.
[0083] S4. The reaction solution of S3 was temperature controlled at 0°C, and 44.2 g of cyclopentadiene was slowly added dropwise. After the addition was completed, the mixture was stirred at 25±3°C for two hours, and then the solvent was removed at 110°C and normal pressure. 92.6 g of crude product was distilled off under reduced pressure. The yield of the product was 52.6%, and the HNMR purity was 84.7%.
[0084] Example 3
[0085] This embodiment provides a method for preparing a cyclopentadienyl tantalum-based metal precursor, wherein the structure of the precursor is: ;
[0086] The preparation method comprises the following steps:
[0087] S1. In a glove box, weigh 1L DME and add it to a reaction flask, and stir it magnetically; under the protection of high-purity nitrogen, cool the reaction flask to -10°C and slowly add 100g NbCl5; maintain the temperature at -10°C and slowly drop 112.4g triethylamine into the reaction flask, and then continue to drop 43.4g tert-butylamine, filter through a G3 funnel, wash the filter cake three times with 75mL DME, combine the filtrates, and prepare intermediate 1.
[0088] S2. Take another three-necked round-bottom flask and replace the nitrogen in it, add 87.69g of n-butyl lithium and 1.6L of n-hexane, cool to -30°C, introduce 61.6g of dimethylamine, and react at 25±3°C for 2h to obtain a reaction solution containing amine metal.
[0089] S3. Slowly drip the filtrate of S1 into the reaction solution of S2, control the temperature of the reaction solution to -10°C, and after dripping, react overnight at 25±3°C for 12 hours to prepare intermediate 2.
[0090] S4. The reaction solution of S3 was temperature controlled at 0°C, and 42.5 g of cyclopentadiene was slowly added dropwise. After the addition was completed, the mixture was stirred at 25±3°C for two hours, and then the solvent was removed at 110°C and normal pressure. 89.4 g of crude product was distilled off under reduced pressure. The yield of the product was 76.1%, and the HNMR purity was 89.3%.
[0091] Example 4
[0092] This embodiment provides a method for preparing a cyclopentadienyl tantalum-based metal precursor, wherein the structure of the precursor is: ;
[0093] The preparation method comprises the following steps:
[0094] S1. In a glove box, weigh 7L DME and add it to a reaction bottle, stir magnetically; cool the reaction bottle to -10°C under the protection of high-purity nitrogen, and slowly add 1000g NbCl5; maintain the temperature at -10°C and slowly drop 749g triethylamine into the reaction bottle, and then continue to drop 275g isopropylamine, filter through a G3 funnel, wash the filter cake three times with 500mL DME, combine the filtrate, and prepare intermediate 1.
[0095] S2. Take another three-necked round-bottom flask and replace the nitrogen in it, add 948g of n-butyl lithium and 11L of n-hexane, cool to -30°C, introduce 875g of methylethylamine, and react at 25±3°C for 2h to obtain a reaction solution containing amine metal.
[0096] S3. Slowly drip the filtrate of S1 into the reaction solution of S2, control the temperature of the reaction solution to -10°C, and after dripping, react overnight at 25±3°C for 12 hours to prepare intermediate 2.
[0097] S4. The reaction solution of S3 was temperature controlled at 0°C, and 245 g of cyclopentadiene was slowly added dropwise. After the addition was completed, the mixture was stirred at 25±3°C for two hours, and then the solvent was removed at 110°C and normal pressure. 665 g of crude product was distilled off under reduced pressure. The yield of the product was 56.6%, and the HNMR purity was 89%.
[0098] Example 5
[0099] This embodiment provides a method for preparing a cyclopentadienyl tantalum-based metal precursor, wherein the structure of the precursor is: ;
[0100] The preparation method comprises the following steps:
[0101] S1. In a glove box, weigh 2 L of toluene and add it to a reaction flask, stir it magnetically; under the protection of high-purity nitrogen, cool the reaction flask to -10°C and slowly add 133 g of TaCl5; maintain the temperature at -10°C and slowly drop 112.4 g of triethylamine into the reaction flask, then continue to drop 43.4 g of tert-butylamine, filter through a G3 funnel, wash the filter cake three times with 200 mL of toluene, combine the filtrates, and prepare intermediate 1.
[0102] S2. Take another three-necked round-bottom flask and replace the nitrogen in it, add 87.7 g of n-butyl lithium and 1.6 L of n-hexane, cool to -30°C, introduce 61.6 g of dimethylamine, and react at 25±3°C for 2 h to obtain a reaction solution containing amine metal.
[0103] S3. Slowly drip the filtrate of S1 into the reaction solution of S2, control the temperature of the reaction solution to -10°C, and after dripping, react overnight at 25±3°C for 12 hours to prepare intermediate 2.
[0104] S4. The reaction solution of S3 was temperature controlled at 0°C, and 42.5 g of cyclopentadiene was slowly added dropwise. After the addition was completed, the mixture was stirred at 25±3°C for two hours, and then the solvent was removed at 110°C and normal pressure. 49.3 g of crude product was distilled off under reduced pressure. The yield of the product was 42.0%, and the HNMR purity was 85%.
[0105] Comparative Example 1
[0106] The method is basically the same as Example 1, except that triethylamine is not used in this comparative example, the amount of triethylamine added in S3 is 0 g, and the amount of tert-butylamine added is 724 g.
[0107] In this comparative example, 553 g of crude product was distilled under reduced pressure with a yield of 47.1% and an HNMR purity of 77%. It contained 9 mol% of CpNb(NtBu)(NHtBu)(NMe2) impurity.
[0108] The precursor after distillation1 H NMR (400MHz, C6D6) characterization data: δ5.87 (s, 5H), 3.18 (s, 6H), 1.36 (s, 9H), 1.27 (s, 9H); HNMR spectrum is attached Figure 2 From the figure and HNMR data, it can be seen that the impurity is difficult to remove by distillation and a qualified precursor product cannot be obtained.
[0109] Comparative Example 2
[0110] The method is basically the same as Example 1, except that triethylamine is replaced by diethylamine in this comparative example, and the amount of diethylamine added is 541.2 g.
[0111] In this comparative example, 571 g of crude product was distilled under reduced pressure, with a yield of 48.6% and a HNMR purity of 80.9%.
[0112] Comparative Example 3
[0113] The method is basically the same as Example 1, except that triethylamine is replaced by aniline in this comparative example, and the amount of aniline added is 689.2 g.
[0114] In this comparative example, 375 g of crude product was distilled under reduced pressure, with a yield of 31.9% and a HNMR purity of 77.4%.
[0115] Comparative Example 4
[0116] The method is basically the same as Example 1, except that triethylamine is replaced by potassium bicarbonate in this comparative example, and the amount of potassium bicarbonate added is 741 g.
[0117] In this comparative example, 409 g of crude product was distilled under reduced pressure, with a yield of 34.8% and a HNMR purity of 69.6%.
[0118] Comparative Example 5
[0119] The method is basically the same as Example 1, except that the amount of triethylamine added in this comparative example is 225 g, and the amount of tert-butylamine added is 651 g.
[0120] In this comparative example, 621 g of crude product was distilled under reduced pressure, with a yield of 51.9% and a HNMR purity of 83.9%.
[0121] Comparative Example 6
[0122] The method is basically the same as Example 1, except that the amount of triethylamine added in this comparative example is 0 g, and the amount of tert-butylamine added is 275 g.
[0123] In this comparative example, 294 g of crude product was distilled under reduced pressure, with a yield of 25.0% and a HNMR purity of 79.7%.
[0124] The precursor after distillation1 H NMR (400MHz, C6D6) characterization data: δ5.87 (s, 5H), 3.18 (s, 6H), 1.36 (s, 9H), 1.27 (s, 9H); HNMR spectrum is attached Figure 3 It can be seen from the figure and HNMR data that the impurities still exist in the precursor after distillation in this comparative example, and a qualified precursor product cannot be obtained.
[0125] Comparative Example 7
[0126] The process is basically the same as that of Example 1, except that in the operation step of S1, the dropping temperature of the materials is 10°C.
[0127] In this comparative example, 376 g of crude product was distilled under reduced pressure, with a yield of 32.0% and a HNMR purity of 81.1%.
[0128] The performance statistics of the above embodiments and comparative examples are shown in Table 1.
[0129] Table 1 Serial number Yield / % HNMR purity / % Example 1 74.3 89.5 Example 2 52.6 84.7 Example 3 76.1 89.3 Example 4 56.6 89.0 Example 5 42.0 85.0 Comparative Example 1 47.1 77.0 Comparative Example 2 48.6 80.9 Comparative Example 3 31.9 77.4 Comparative Example 4 34.8 69.6 Comparative Example 5 51.9 83.9 Comparative Example 6 25.0 79.7 Comparative Example 7 32.0 81.1
[0130] According to Table 1, the nuclear magnetic purity of the crude product prepared by the preparation method of the present invention is basically above 85%, and the product yield is also good, but the reaction conditions such as the type and amount of active substances need to be strictly controlled; compared with the prior art, the reaction time can be effectively shortened, and the crude product obtained by the method can obtain a product with a component purity of ≥99.5% and a metal purity of 6N after vacuum distillation, and these products can be used as precursor materials for semiconductor thin film deposition.
[0131] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0132] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a cyclopentadienyl tantalum metal precursor, characterized in that: The following steps are involved: (1) at least a tantalum metal source, a primary amine having an R1NH2 structure, and an active material having an NR'R"2 structure are mixed and reacted to prepare an intermediate 1; (2) At least intermediate 1 and M1(NR2R3) x The structure of the amine metal reaction to prepare intermediate 2; (3) adding cyclopentadiene to the intermediate 2 to obtain a cyclopentadienyl tantalum metal precursor product; The cyclopentadienyl tantalum metal precursor has a structure of Formula 1: (Formula 1); Wherein, M is a tantalum metal selected from vanadium, niobium, and tantalum; R is any one of H, a C1-C6 alkyl group, a C1-C6 alkoxy group, a silane group, a substituted amine group, and an alkylamide group; n is an integer of 0-5; R1 is a C1-C5 alkyl group; R2 and R3 are independently selected from any one of a substituted or unsubstituted C1-C8 alkyl group, wherein the substituent includes at least one of an alkoxy group, an alkylamine group, an ester group, and an alkylamide group.
2. The preparation method according to claim 1, characterized in that: The R2 and R3 are independently selected from unsubstituted C1-C8 alkyl groups; the R1 is a C1-C4 alkyl group.
3. The preparation method according to claim 1, characterized in that: The R2 and R3 are independently selected from any one of methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, cyclohexyl, heptyl and octyl; Preferably, R1 is selected from any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl and tert-butyl.
4. The preparation method according to any one of claims 1 to 3, characterized in that The tantalum metal source includes tantalum metal halide and / or tantalum metal oxyhalide. When the tantalum metal is vanadium, the tantalum metal source is tantalum metal oxyhalide. When the tantalum metal source is niobium or tantalum, the tantalum metal source is tantalum metal halide. Preferably, the tantalum metal halide is selected from at least one of chloride, bromide and iodide, and the tantalum metal oxyhalide is oxychloride; Preferably, R' and R" in the active substance are independently selected from C1-C5 alkyl groups; Preferably, the molar ratio of the tantalum metal source, the primary amine and the active material is 1:1-2:1-3.
5. The preparation method according to claim 4, characterized in that: The active substance is at least one selected from triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, tri-n-pentylamine, dimethylethylamine, dimethylpropylamine, dimethylbutylamine, diethylmethylamine, diethylpropylamine, and dimethylbutylamine; Preferably, the molar ratio of the tantalum metal source, the primary amine and the active material is 1:1-1.6:2-3.
6. The preparation method according to claim 1, characterized in that: The reaction in step (1) is carried out in a first organic solvent, wherein the first organic solvent comprises at least one of n-butane, n-pentane, n-hexane, n-heptane, n-octane, toluene, xylene, carbon tetrachloride, dimethyl ether, tetrahydrofuran, and diethyl ether; preferably, the first organic solvent comprises dimethyl ether; Preferably, the mass concentration of the tantalum-based metal source in step (1) is 30-600 g / L.
7. The preparation method according to claim 1, characterized in that: The M1(NR2R3) x In the amine metal of the structure, M1 is selected from Li, Na, K, Mg, Ca, Sr, and x is the valence of M1; Preferably, the molar ratio of the tantalum metal source to the amine metal is 1:2.5-5; Preferably, M1(NR2R3) can be added directly x The amine metal itself can also be indirectly obtained by adding a hydrocarbon metal M1Y and a secondary amine HNR2R3 to react to obtain M1(NR2R3) x Amine metal of the structure; Y in M1Y is an alkyl, alkenyl or alkynyl group; Preferably, the molar ratio of the tantalum metal source to the hydrocarbon-based metal is 1:0.5-5. Preferably, the molar ratio of the tantalum metal source to the secondary amine is 1:0.8-5.
8. The preparation method according to claim 7, characterized in that: The alkylated metal M1Y includes at least one of methyl lithium, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, phenyl lithium, methylphenyl lithium, vinyl lithium, acetylide lithium, acetylide sodium, methyl sodium, ethyl sodium, n-propyl sodium, isopropyl sodium, n-butyl sodium, sec-butyl sodium, tert-butyl sodium, phenyl sodium, methylphenyl sodium, sodium acetylide, disodium acetylide, sodium butylide, n-butyl potassium, sec-butyl potassium, tert-butyl potassium, amyl potassium, diethyl magnesium, and dibutyl magnesium; Preferably, the reaction temperature of steps (1)-(2) is below -5°C, and the reaction time of step (2) is 5-48h; Preferably, the reaction temperature of step (3) is 5-35° C., and the reaction time of step (3) is 0.5-10 h.
9. A cyclopentadienyl tantalum metal precursor prepared by the preparation method according to any one of claims 1 to 8, characterized in that: The precursor has a structure shown in the following formula 1: (Formula 1); The precursor includes ≤10% by mole percentage of the substance shown in formula 2: (Formula 2); Wherein, M, R, R1-R3, and n are as defined above; It preferably includes ≤5 mol% of the substance represented by formula 2, and more preferably does not include the substance represented by formula 2.
10. Use of the cyclopentadienyl tantalum metal precursor according to claim 9 in preparing semiconductor thin films.