High-purity organometallic film precursor and preparation method therefor

Abstract

The present application discloses a high-purity organometallic film precursor and a preparation method therefor. The method comprises: under nitrogen protection, loading a metal halide into a flask, adding an ether solvent, and cooling to a temperature A; slowly injecting methylmagnesium chloride into the flask over a set period of time while controlling the reaction temperature to not exceed a temperature B; after injection, raising the reaction temperature to a temperature C and stirring during reflux; upon completion of reflux, cooling the reaction solution back to the temperature A, and slowly adding a prepared Grignard reagent into the reaction solution while controlling the reaction temperature to not exceed the temperature B during the addition; after injection, raising the reaction temperature to the temperature C and stirring during reflux; upon completion of the reaction, separating magnesium chloride by means of vacuum filtration, and removing the solvent by means of filtrate vacuum distillation, to obtain the organometallic film precursor. The present application has the advantages of good process safety, high yield, high product purity, and high preparation efficiency.

Description

A high-purity organometallic thin film precursor and its preparation method

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 2024114449039, filed on October 16, 2024, entitled "A High-Purity Organometallic Thin Film Precursor and Its Preparation Method", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of semiconductors and relates to the preparation of organometallic amine compounds, specifically to a high-purity organometallic thin film precursor and its preparation method. Background Technology

[0004] Oxides are important substrates in semiconductors, displays, and other applications, attracting significant attention in various fields such as semiconductor devices, light-emitting diodes (LEDs), and solar cells. To achieve high-resolution displays, transistor thin-film materials with high charge carrier mobility are needed as channels.

[0005] The channel regions of existing thin-film transistors are mainly composed of amorphous silicon (α-Si). However, amorphous silicon (α-Si) has limitations in the realization of high-definition displays due to its low charge mobility and the need for high manufacturing process temperatures exceeding 350°C.

[0006] To achieve high-definition displays, a new material needs to be developed to replace amorphous silicon (α-Si) used in the channel regions of thin-film transistors (TFTs). For example, TFTs using ZnO-based amorphous oxide semiconductors exhibit high uniformity in terms of charge mobility and electrical and optical properties. However, because zinc oxide films are prone to crystallization during deposition, it is difficult to obtain amorphous phases suitable for large-area orientation, and the presence of crystalline particles leads to drawbacks such as low device mobility and potential threshold voltage scaling. Another approach is to propose TFTs using amorphous InGaZnO (indium gallium zinc oxide; hereinafter IGZO) as the active layer. Active layers composed of IGZO can improve device performance due to their high mobility of approximately 10 cm² / Vs. IGZO films are typically fabricated using sputtering with IGZO targets, but this suffers from difficulties in controlling the film composition and reduced device reliability. Methods for preparing IGZO films using atomic layer deposition (ALD) or precursor chemical vapor deposition (CVD) have been emphasized. The composition of IGZO thin films can be easily adjusted during ALD or CVD fabrication, offering the advantage of fully expressing the electrical performance of transistor devices through a uniform film. Common precursors for IGZO thin film preparation via ALD or CVD include trimethylindium (TMI), trimethylgadolinium (TMG), and diethylzinc (DEZ). While precursors like TMG and DEZ are liquid at room temperature, and film deposition is possible with high vapor pressure using ALD or CVD and uniform composition control and precursor supply, TMI offers the advantage of a relatively high vapor pressure. However, its solid state at room temperature presents challenges in achieving uniform precursor supply and particle size distribution during film preparation, making the process relatively difficult.

[0007] Therefore, liquid indium and other Group 13 organometallic precursors are needed. These precursors are essential for atomic layer deposition and CVD processes at room temperature and can suppress spontaneous combustion in moisture or air. For this purpose, [(3-dimethylamino)propyl]dimethylindium has emerged as a liquid indium precursor. [(3-dimethylamino)propyl]dimethylindium precursors are liquid at room temperature, have a relatively high vapor pressure, and, unlike alkyl organometallic precursors (TMG, TMI, DEZ, etc.) primarily used for IGZO thin film deposition, also exhibit suppressed spontaneous combustion in moisture or air. Its advantage lies in its ability to be safely handled during thin film fabrication.

[0008] However, known methods for preparing [(3-dimethylamino)propyl]dimethylindium compounds involve the use of hazardous alkali metals such as lithium, sodium, and potassium, or the use of aluminum silses to produce the corresponding metal silses. These processes are cumbersome and prone to generating difficult-to-separate impurities, thus reducing yield. The aforementioned methods for preparing [(3-dimethylamino)propyl]dimethylindium compounds require additional steps to obtain the starting materials, resulting in low preparation efficiency. Summary of the Invention

[0009] Purpose of the invention: In order to overcome the shortcomings of the existing technology, a high-purity organometallic thin film precursor and its preparation method are provided, which has the advantages of good safety in the preparation process, high yield, high product purity and high preparation efficiency.

[0010] Technical solution: To achieve the above objectives, this application provides a high-purity organometallic thin film precursor, the structural expression of which is as follows:

[0011] Furthermore, an organometallic thin film precursor was obtained by reacting a metal halide with a prepared Grignard reagent, wherein,

[0012] The structural formula for metal halides is:

[0013] The structural formula of Grignard reagents is:

[0014] The reaction formula is:

[0015] Wherein, M is a Group 13 metal, which can be boron, aluminum, gallium, or indium, preferably indium; X is a halogen, including F, Cl, Br, and I, preferably Cl or Br; n is an integer from 1 to 9; R1, R3, R 11 R 12 It is one of hydrogen, alkyl (C1-C10), alkoxy (C1-C10), cycloalkyl (C3-C12), and heterocycloalkyl (C3-C12), independent of each other, and may be further substituted by one or more substituents selected from halogen, trifluoromethyl, amino, cyano, and hydroxyl. Further, the organometallic film precursor is an organometallic amine compound, comprising the following structure:

[0016] The alkyl and alkoxy substituents include both straight-chain and branched forms, and have 1 to 3 carbon atoms;

[0017] Alkoxy groups refer to non-aromatic monocyclic or polycyclic systems with 3 to 12 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; polycyclic alkyl groups include perhydronaphthyl, perhydroindenyl, etc.; bridged polycyclic alkyl groups include adamantyl and norbornyl, etc.

[0018] Heterocyclic alkyl refers to a non-aromatic 3- to 12-membered ring free radical consisting of a carbon atom and 1 to 5 heteroatoms selected from nitrogen, phosphorus, oxygen and sulfur, and heterocyclic chloroalkyl free radicals may be fused, bridged or may contain a helical ring system, and the nitrogen, phosphorus, carbon, oxygen or sulfur atoms in the heterocycle may be oxidized in various oxidation states as appropriate.

[0019] This application also provides a method for preparing a high-purity organometallic thin film precursor, comprising the following steps:

[0020] S1: Under nitrogen protection, the metal halide is placed into a flask and an ether solvent is injected, and then cooled to temperature A;

[0021] S2: Slowly inject methyl magnesium chloride into the flask within a set time, while controlling the reaction temperature to not exceed temperature B during the process;

[0022] S3: After injection, raise the reaction temperature to temperature C and stir under reflux;

[0023] S4: After reflux, cool the reaction solution to temperature A again, and slowly inject the prepared Grignard reagent into the reaction solution, controlling the reaction temperature not to exceed temperature B during the injection process;

[0024] S5: After injection, raise the reaction temperature to temperature C and stir under reflux;

[0025] S6: After the reaction is terminated, magnesium chloride is separated by vacuum filtration, and the solvent is removed by vacuum distillation of the filtrate to obtain the organometallic film precursor.

[0026] Furthermore, in step S1, the metal halide is indium trichloride, the ether solvent is diethyl ether, and the temperature A is 0℃~10℃.

[0027] Furthermore, in step S2, the time is set to 28-32 minutes and the temperature B is 30°C.

[0028] Furthermore, in steps S3 and S5, the temperature C is 35°C, and the stirring and reflux time is 12 hours.

[0029] Furthermore, the Grignard reagent in step S4 is an alkyl magnesium halide. The Grignard reagent can be used in quantities of 2.0 to 2.5 moles.

[0030] Beneficial effects: Compared with the prior art, this application has the following advantages:

[0031] 1. The entire preparation process avoids the use of hazardous compounds such as lithium, sodium, and potassium, ensuring the safety of the preparation process.

[0032] 2. Precise control of raw material equivalents, addition rate, and system reaction temperature during the preparation process reduces impurities, resulting in high yield and high purity of the final product.

[0033] 3. The preparation process has a shorter reaction time, higher final yield, higher product purity, and higher overall preparation efficiency.

[0034] 4. The preparation process is convenient and safe. The preparation process uses a one-pot reaction method, which avoids additional processing of highly active products and intermediates, making it both convenient and safe. Attached Figure Description

[0035] Figure 1 shows the 1H-NMR spectrum of [3-(dimethylamino)propyl]dimethylindium prepared in Example 1. Detailed Implementation

[0036] The present application is further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present application. After reading the present application, any modifications of the present application in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

[0037] This application provides a high-purity organometallic thin film precursor, the structural expression of which is as follows:

[0038] Organometallic thin film precursors were obtained by reacting metal halides with prepared Grignard reagents, wherein...

[0039] The structural formula for metal halides is:

[0040] Grignard reagents are formed by the reaction of halogenated magnesium compounds with metallic magnesium in anhydrous diethyl ether or tetrahydrofuran to form alkyl magnesium halides RMgX. These organomagnesium compounds are called Grignard reagents.

[0041] The structural formula of Grignard reagents is:

[0042] The reaction formula is:

[0043] Wherein, M is a Group 13 metal, which can be boron, aluminum, gallium, or indium, preferably indium; X is a halogen, including F, Cl, Br, and I, preferably Cl or Br; n is an integer from 1 to 9; R1, R3, R 11 R 12It is one of hydrogen, alkyl (C1-C10), alkoxy (C1-C10), cycloalkyl (C3-C12), and heterocycloalkyl (C3-C12), independent of each other, and may be further substituted by one or more substituents selected from halogens, trifluoromethyl, amino, cyano, and hydroxyl. The alkyl and alkoxy substituents include both straight-chain and branched forms and have 1 to 3 carbon atoms; the organometallic film precursor is an organometallic amine compound, including the following structure:

[0044] Alkoxy groups refer to non-aromatic monocyclic or polycyclic systems with 3 to 12 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; polycyclic alkyl groups include perhydronaphthyl, perhydroindenyl, etc.; bridged polycyclic alkyl groups include adamantyl and norbornyl, etc.

[0045] Heterocyclic alkyl refers to a non-aromatic 3- to 12-membered ring free radical consisting of a carbon atom and 1 to 5 heteroatoms selected from nitrogen, phosphorus, oxygen and sulfur, and heterocyclic chloroalkyl free radicals may be fused, bridged or may contain a helical ring system, and the nitrogen, phosphorus, carbon, oxygen or sulfur atoms in the heterocycle may be oxidized in various oxidation states as appropriate.

[0046] This application also provides a method for preparing a high-purity organometallic thin film precursor, comprising the following steps:

[0047] S1: Under nitrogen protection, the metal halide is placed into a flask and an ether solvent is injected, and then cooled to temperature A;

[0048] The metal halide is indium trichloride, the ether solvent is diethyl ether, and the temperature A is 0℃~10℃.

[0049] S2: Slowly inject methyl magnesium chloride into the flask within a set time, while controlling the reaction temperature to not exceed temperature B during the process;

[0050] Set the time to 28–32 minutes and the temperature B to 30°C;

[0051] S3: After injection, raise the reaction temperature to temperature C and stir and reflux; temperature C is 35°C, and the stirring and reflux time is 12 hours;

[0052] S4: After reflux, cool the reaction solution to temperature A again, and slowly inject the prepared Grignard reagent into the reaction solution, controlling the reaction temperature not to exceed temperature B during the injection process;

[0053] Alkyl magnesium halide, specifically 3-(dimethylamino)propyl magnesium chloride; Grignard reagent can be used in 2.0 to 2.5 mol amounts;

[0054] S5: After injection, raise the reaction temperature to temperature C and stir and reflux; temperature C is 35°C, and the stirring and reflux time is 12 hours;

[0055] S6: After the reaction is terminated, magnesium chloride is separated by vacuum filtration, and the solvent is removed by vacuum distillation of the filtrate to obtain the organometallic film precursor.

[0056] Based on the above scheme, the scheme of this application is applied in an example. The organometallic thin film precursor is an organic methylamine compound, specifically [3-(dimethylamino)propyl]dimethylindium ([(3-dimethylamino)propyl]dimethylindium), as follows:

[0057] Example 1:

[0058] Under nitrogen protection, 50 g (1 eq) of indium trichloride was placed in a flask and 300 mL of diethyl ether was added. The flask was then cooled to 10 °C. 137 g (2 eq) of methylmagnesium chloride was slowly injected over 30 minutes, with the reaction temperature not exceeding 30 °C. After injection, the flask was heated to 35 °C and refluxed with stirring for 12 hours. After reflux, the reaction solution was cooled to 10 °C again, and 115 g (1 equivalent) of 3-(dimethylamino)propylmagnesium chloride was slowly injected, carefully not exceeding 30 °C. After injection, the flask was heated to 35 °C and refluxed with stirring for 12 hours. After the reaction was terminated, magnesium chloride was separated by vacuum filtration. The solvent was removed by vacuum distillation of the filtrate. To improve purity, vacuum distillation (30 °C / 0.5 Torr) was performed to give 48 g (92% yield) of [(3-dimethylamino)propyl]dimethylin liquid.

[0059] As shown in Figure 1, HNMR (C6D6): δ -0.13 (s, 6H), 0.65 (t, 2H), 1.70 (tt, 2H), 1.76 (s, 6H), 1.78 (t, 2H).

[0060] Example 2:

[0061] Under nitrogen protection, 50 g (1 eq) of indium trichloride was placed in a flask and 300 mL of diethyl ether was added. The mixture was then cooled to 0 °C. 137 g (2 eq) of methylmagnesium chloride was slowly injected over 28 minutes, with the reaction temperature not exceeding 30 °C. After injection, the mixture was raised to 35 °C and refluxed with stirring for 12 hours. After reflux, the reaction solution was cooled again to approximately 0 °C, and 115 g (1 equivalent) of 3-(dimethylamino)propylmagnesium chloride was slowly injected, carefully not exceeding 30 °C. After injection, the mixture was raised to 35 °C and refluxed with stirring for 12 hours. After the reaction was terminated, magnesium chloride was separated by vacuum filtration. The solvent was removed by vacuum distillation of the filtrate. To improve purity, vacuum distillation (44 °C / 2.2 Torr) was performed to give 46 g (88% yield) of [(3-dimethylamino)propyl]dimethylin liquid.

[0062] Example 3:

[0063] Under nitrogen protection, 50 g (1 eq) of indium trichloride was placed in a flask and 300 mL of diethyl ether was added. The flask was then cooled to 5°C. 171 g (2 eq) of methylmagnesium chloride was slowly injected over 32 minutes, with the reaction temperature not exceeding 30°C. After injection, the flask was heated to 35°C and refluxed with stirring for 12 hours. After reflux, the reaction solution was cooled to 5°C again, and 115 g (1 equivalent) of 3-(dimethylamino)propylmagnesium chloride was slowly injected, carefully maintaining a reaction temperature not exceeding 30°C. After injection, the flask was heated to 35°C and refluxed with stirring for 12 hours. After the reaction was terminated, magnesium chloride was separated by vacuum filtration. The solvent was removed by vacuum distillation of the filtrate. To improve purity, vacuum distillation (30°C / 0.5 Torr) was performed to obtain 36 g (70% yield) of [(3-dimethylamino)propyl]dimethylin liquid.

[0064] Comparative Example 1:

[0065] In this comparative example, the preparation methods of Examples 1-3 are compared and analyzed with existing preparation methods and products of [(3-dimethylamino)propyl]dimethylindium compounds, as shown in the table below:

Claims

1. A high-purity organometallic thin film precursor, characterized in that, Its structural expression is:

2. The high-purity organometallic thin film precursor according to claim 1, characterized in that, Organometallic thin film precursors were obtained by reacting metal halides with prepared Grignard reagents, wherein... The structural formula for metal halides is: The structural formula of Grignard reagents is: The reaction formula is: Where M is a Group 13 metal, X is a halogen, and n is an integer from 1 to 9; R1, R3, R 11 R 12 It is one of hydrogen, alkyl, alkoxy, cycloalkyl, and heterocycloalkyl, and each is independent of the others.

3. The high-purity organometallic thin film precursor according to claim 2, characterized in that, The organometallic thin film precursor is an organometallic amine compound, comprising the following structure:

4. The high-purity organometallic thin film precursor according to claim 2, characterized in that, The alkyl and alkoxy substituents include both straight-chain and branched forms and have 1 to 6 carbon atoms; Alkoxy groups refer to non-aromatic monocyclic or polycyclic systems having 3 to 12 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Heterocyclic alkyl groups are non-aromatic 3- to 12-membered ring free radicals consisting of a carbon atom and 1 to 5 heteroatoms selected from nitrogen, phosphorus, oxygen, and sulfur, whether substituted or unsubstituted.

5. A method for preparing a high-purity organometallic thin film precursor, characterized in that, Includes the following steps: S1: Under nitrogen protection, the metal halide is placed into a flask and an ether solvent is injected, and then cooled to temperature A; S2: Slowly inject methyl magnesium chloride into the flask within a set time, while controlling the reaction temperature to not exceed temperature B during the process; S3: After injection, raise the reaction temperature to temperature C and stir under reflux; S4: After reflux, cool the reaction solution to temperature A again, and slowly inject the prepared Grignard reagent into the reaction solution, controlling the reaction temperature not to exceed temperature B during the injection process; S5: After injection, raise the reaction temperature to temperature C and stir under reflux; S6: After the reaction is terminated, magnesium chloride is separated by vacuum filtration, and the solvent is removed by vacuum distillation of the filtrate to obtain the organometallic film precursor.

6. The method for preparing a high-purity organometallic thin film precursor according to claim 5, characterized in that, In step S1, the metal halide is indium trichloride, the ether solvent is diethyl ether, and the temperature A is 0℃~10℃.

7. The method for preparing a high-purity organometallic thin film precursor according to claim 5, characterized in that, In step S2, the time is set to 28-32 minutes and the temperature B is 30°C.

8. The method for preparing a high-purity organometallic thin film precursor according to claim 5, characterized in that, In steps S3 and S5, the temperature C is 35°C, and the stirring and reflux time is 12 hours.

9. The method for preparing a high-purity organometallic thin film precursor according to claim 5, characterized in that, In step S4, the Grignard reagent is alkyl magnesium halide.

Images