Preparation method of atomic layer deposition precursor material
By using precipitants such as sodium chloride, potassium chloride, and lithium bromide in the preparation process of atomic layer deposition precursor materials, the problems of difficult solid-liquid separation and long synthesis cycle have been solved, the product yield and purity have been improved, green and environmentally friendly production has been achieved, and corporate efficiency has been enhanced.
Patent Information
- Application Number
- CN202511771319.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-28
- Publication Date
- 2026-02-27
AI Technical Summary
Existing technologies for preparing atomic layer deposition precursor materials suffer from problems such as difficulty in solid-liquid separation, long synthesis cycles, low product purity, and low yield. In particular, during the preparation of titanium, zirconium, hafnium oxide and nitride precursor materials, the filters are prone to clogging, and the complex composition inside the reactor leads to thermal decomposition and impurity carry-out problems.
Sodium chloride, potassium chloride, lithium bromide, and lithium iodide are used as precipitants. By adding these precipitants after the reaction, the solid-liquid separation of the materials in the reactor is promoted. The complex ions formed by the precipitants and lithium chloride are dispersed in the solvent, which reduces the difficulty of solid-liquid separation. The corresponding boiling point fractions are collected by vacuum distillation, which simplifies the post-processing.
It reduces the difficulty of solid-liquid separation, shortens the synthesis cycle, increases the yield per batch, reduces the amount of organic solvents used and waste liquid discharge, improves product purity and the economic benefits of enterprises, and achieves green and environmentally friendly production.
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of compound synthesis, and particularly relates to a preparation method of an atomic layer deposition precursor material. BACKGROUND
[0002] With the rapid development of integrated circuits, SiO2 as a traditional gate dielectric cannot meet the requirements of high integration of MOSFET (Metal Oxide Semiconductor Field Effect Transistor) devices, and a new High-k material needs to be used to replace the traditional SiO2. Such a material needs to have good high dielectric constant, k>20; good thermal stability with silicon; always be amorphous to reduce leakage current; have a large band gap and high barrier height to reduce breakdown current. Titanium, zirconium and hafnium oxides and nitrides just meet these requirements.
[0003] Titanium, zirconium and hafnium nitride and oxide precursors mainly come from compounds such as tetra (dimethylamino) titanium, tetra (dimethylamino) zirconium, tetra (methyl ethyl amino) zirconium, tetra (dimethylamino) hafnium, tetra (methyl ethyl amino) hafnium and the like. These compounds are mainly prepared by reacting alkyl amine and n-butyl lithium to generate alkyl amine lithium, then reacting with metal chloride, and then being treated to obtain the product.
[0004] Common post-treatment methods include two kinds of methods of filtering to remove the solvent and then evaporating, and directly evaporating. The first method has a large change in the particle size of the filter residue with reaction conditions and other factors, and often causes the filter mesh to be blocked or the impurities to be not intercepted during filtration, and the separation is time-consuming and labor-consuming. The second method directly evaporates, because the components in the reaction kettle are complex, the kettle temperature needs to be raised very high, which easily causes thermal decomposition of the product, and because there are many lithium salts in the kettle, the lithium salts are brought out during the evaporation of the product, which affects the purity of the product, reduces the yield of the product, and brings difficulty to the cleaning of the reaction kettle, and prolongs the production cycle of a single batch. SUMMARY
[0005] Based on this, the application provides a preparation method of an atomic layer deposition precursor material. The method can reduce the difficulty of solid-liquid separation, shorten the synthesis cycle, improve the yield of a single batch, reduce the amount of organic solvent and the discharge of waste liquid, improve the economic benefit of enterprises, and is green and environmentally friendly.
[0006] The specific technical scheme of the application is as follows:
[0007] A preparation method of an atomic layer deposition precursor material, the atomic layer deposition precursor material is an ammonia metal compound, and the preparation method comprises the following steps:
[0008] 1) mixing an alkane solvent and n-butyl lithium to prepare a first reactant;
[0009] 2) adding alkyl amine to the first reactant to perform a first reaction to prepare a second reactant;
[0010] 3) adding metal chloride to the second reactant to perform a second reaction to prepare a third reactant, and performing post-treatment to obtain the metal amide compound;
[0011] The post-treatment step comprises: after the second reaction is completed, adding a precipitant to the obtained mixture, and after the addition is completed, standing for 1-2 hours until the solid and liquid are obviously separated, and then using a pipette to transfer the supernatant to a distillation kettle for reduced pressure distillation to collect a corresponding boiling point fraction.
[0012] In one of the embodiments, the alkane solvent is one or more of n-pentane, n-hexane, n-heptane, and toluene.
[0013] In one of the embodiments, the alkyl amine is one of dimethylamine, methylethylamine, and diethylamine.
[0014] In one of the embodiments, the reaction condition temperature of the first reaction is -30-0°C.
[0015] In one of the embodiments, after the first reaction is completed, the reflux temperature of the second reactant is 50-70°C.
[0016] In one of the embodiments, after the first reaction is completed, the reflux time of the second reactant is 1-3 hours.
[0017] In one of the embodiments, the metal chloride is one of titanium tetrachloride, zirconium tetrachloride, and hafnium tetrachloride.
[0018] In one of the embodiments, the reaction condition temperature of the second reaction is -30-0°C.
[0019] In one of the embodiments, after the second reaction is completed, the reflux temperature of the third reactant is 50-70°C.
[0020] In one of the embodiments, after the second reaction is completed, the reflux time of the third reactant is 8-24 hours.
[0021] In one of the embodiments, the precipitant is one of sodium chloride, potassium chloride, lithium bromide, and lithium iodide.
[0022] In one of the embodiments, the molar ratio of the alkyl amine to n-butyllithium is 1.1-1.2.
[0023] In one of the embodiments, the molar ratio of the second reactant to the metal chloride is 1:4.1-4.2.
[0024] The present application finds a series of precipitants, sodium chloride, potassium chloride, lithium bromide, lithium iodide, from the perspective of promoting solid-liquid separation of the materials in the kettle. The solid by-product of the materials in the kettle is lithium chloride, and the supernatant is the product, excess organic amine and alkane solvent. Lithium chloride can form a complex ion [Li(R1R2NH)]4 with amine substances. + The ion is dispersed in the solvent in the form of emulsion and is not easy to settle, thus leading to difficulty in solid-liquid separation. Since the ionization constant of the precipitant such as lithium chloride is a constant value, the addition of Li + or Cl - compounds into the reaction system can inhibit the ionization degree of lithium chloride in the original system, so that lithium chloride can be more completely settled. In addition, the anion or cation in the added precipitant is larger than the relative atomic mass of the chloride ion or lithium ion, otherwise new difficult-to-settle impurities will be introduced.
[0025] The present application synthesizes atomic layer deposition precursor materials with metal chlorides or non-chlorine lithium salts, and uses sodium chloride, potassium chloride, lithium bromide, lithium iodide and the like as a series of precipitants. The method of the present application reduces the difficulty of solid-liquid separation, shortens the synthesis cycle, improves the single-batch yield, reduces the amount of organic solvent and the discharge of waste liquid, is green and environmentally friendly, and greatly improves the economic benefit of enterprises. DETAILED DESCRIPTION
[0026] In order to fully understand the purposes, features and effects of the present application, the technical solutions of the present application will be further described below in conjunction with examples, but the protection scope of the present application is not limited to the following examples. In addition, after reading the content taught by the present application, those skilled in the art can make various modifications or changes to the present application, and these equivalent forms also fall within the scope defined by the appended claims of the present application.
[0027] Example 1
[0028] A synthesis method of titanium tetra(dimethylamino), the specific steps are as follows:
[0029] Step one, the reaction device is a 200L reaction kettle, the reaction device is replaced with nitrogen gas / vacuum three times, 60L n-hexane and 55L n-butyllithium hexane solution (2.5M) are added under nitrogen atmosphere; to obtain the first reactant;
[0030] Step two, control the temperature in the reaction kettle to be -20℃, slowly pass 7kg of dimethylamine into the first reactant, after passing, the temperature in the kettle is increased to 50℃, and the reaction is carried out for 1 hour to obtain the second reactant;
[0031] Step three, control the temperature in the reactor at -20°C, slowly pass 6.362 kg of titanium tetrachloride into the reaction device, after the completion of the pass, the temperature in the reactor is raised to 60°C, and the reaction is carried out for 12 hours to obtain a third reactant;
[0032] Step four, 1 kg of sodium chloride is added into the reactor, the stirring is stopped, and the settlement is carried out for 1 hour, then the supernatant is transferred into a distillation reactor by using a pipette for reduced pressure distillation, the fraction of 50°C / 0.1 mmHg is collected, and 6.761 kg of titanium tetrakis(dimethylamido) is obtained with a yield of 90%.
[0033] Example 2
[0034] The synthesis method of titanium tetrakis(dimethylamido) in this example is as follows:
[0035] Step one, the reaction device is a 200 L reactor, the reaction device is replaced with nitrogen / vacuum for three times, 60 L of n-hexane and 60 L of n-butyllithium hexane solution (2.5 M) are added under nitrogen atmosphere to obtain a first reactant;
[0036] Step two, the temperature in the reactor is controlled at -20°C, 9.75 kg of methyl ethylamine is slowly passed into the first reactant, after the completion of the pass, the temperature in the reactor is raised to 55°C, and the reaction is carried out for 1 hour to obtain a second reactant;
[0037] Step three, the temperature in the reactor is controlled at -20°C, 8.53 kg of zirconium tetrachloride is slowly passed into the reaction device, after the completion of the pass, the temperature in the reactor is raised to 65°C, and the reaction is carried out for 18 hours to obtain a third reactant;
[0038] Step four, 1 kg of potassium chloride is added into the reactor, the stirring is stopped, and the settlement is carried out for 1 hour, then the supernatant is transferred into a distillation reactor by using a pipette for reduced pressure distillation, the fraction of 81°C / 0.01 mmHg is collected, and 10.42 kg of zirconium tetrakis(methyl ethylamido) is obtained with a yield of 88%.
[0039] Example 3
[0040] The synthesis method of hafnium tetrakis(diethylamido) in this example is as follows:
[0041] Step one, the reaction device is a 200 L reactor, the reaction device is replaced with nitrogen / vacuum for three times, 60 L of n-hexane and 60 L of n-butyllithium hexane solution (2.5 M) are added under nitrogen atmosphere to obtain a first reactant;
[0042] Step two, the temperature in the reactor is controlled at -20°C, 12.07 kg of diethylamine is slowly passed into the first reactant, after the completion of the pass, the temperature in the reactor is raised to 60°C, and the reaction is carried out for 1 hour to obtain a second reactant;
[0043] Step three, the temperature in the reaction kettle is controlled at -20 DEG C, 11.72 kg hafnium tetrachloride is slowly introduced into the reaction device, after the introduction, the temperature in the kettle is increased to 70 DEG C, and the reaction is carried out for 20 hours to obtain the third reactant;
[0044] Step four, 1 kg lithium bromide is added into the kettle, the stirring is stopped, and the kettle is settled for 1 hour, then the supernatant is transferred into a distillation kettle by a pipette, and is distilled under reduced pressure to collect the fraction at 130 DEG C / 0.01 mmHg to obtain 15.72 kg tetra (diethylamino) hafnium with a yield of 92%.
[0045] The method can reduce the difficulty of solid-liquid separation, shorten the synthesis cycle, improve the yield of single batch, reduce the amount of organic solvent and waste liquid discharge, improve the economic benefit of enterprises, and is green and environmental protection.
[0046] The above describes the preferred embodiments of the present application in detail, but the present application is not limited to the specific details in the above embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.
[0047] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction, and in order to avoid unnecessary repetition, the present application will not further describe various possible combination manners.
[0048] In addition, various different embodiments of the present application can also be combined in any manner, as long as it does not deviate from the technical concept of the present application, and it should be considered as the disclosed content of the present application.
Claims
1. A method for preparing an atomic layer deposition precursor material, characterized in that, The atomic layer deposition precursor material is an amino metal compound, and the preparation method includes the following steps; 1) Prepare the first reactant by mixing an alkane solvent with n-butyllithium; 2) An alkylamine is added to the first reactant to carry out a first reaction, thereby preparing a second reactant; 3) Add a metal chloride to the second reactant to carry out a second reaction, prepare a third reactant, and obtain the amino metal compound after post-treatment; The post-processing steps include: after completing the second reaction, adding a precipitant to the resulting mixture, letting it stand for 1-2 hours until the solid and liquid are clearly separated, transferring the supernatant to a distillation vessel for vacuum distillation, and collecting the corresponding boiling point fraction.
2. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, The alkane solvent is one or more of n-pentane, n-hexane, n-heptane, and toluene.
3. The method for preparing atomic layer deposition precursor materials according to claim 1, characterized in that, The alkylamine is one of dimethylamine, methyl ethylamine, and diethylamine.
4. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, The reaction conditions for the first reaction are -30 to 0°C; the reaction conditions for the second reaction are -30 to 0°C.
5. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, After the first reaction is completed, the reflux temperature of the second reactant is 50~70℃, and the reflux time is 1~3 hours.
6. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, The metal chloride is one of titanium tetrachloride, zirconium tetrachloride, and hafnium tetrachloride.
7. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, After the second reaction is completed, the reflux temperature of the third reactant is 50~70℃, and the reflux time is 8~24 hours.
8. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, The precipitant is one of sodium chloride, potassium chloride, lithium bromide, and lithium iodide.
9. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, The molar ratio of the alkylamine to n-butyllithium is 1.1 to 1.
2.
10. The method for preparing the atomic layer deposition precursor material according to claim 1, characterized in that, The molar ratio of the second reactant to the metal chloride is 1:4.1~4.2.