High-purity organic metal film precursor and preparation method thereof

Abstract

The invention discloses a high-purity organic metal film precursor and a preparation method thereof.The method comprises the steps that under nitrogen protection, metal halide is put into a flask, an ether solvent is injected, and the mixture is cooled to the temperature A; slowly injecting methylmagnesium chloride into the flask within a set time, and controlling the reaction temperature not to exceed the temperature B in the process; after injection is completed, raising the reaction temperature to a temperature C, and stirring and refluxing; after the reflux is completed, cooling the reaction solution to the temperature A again, slowly injecting the prepared Grignard reagent into the reaction solution, and controlling the reaction temperature not to exceed the temperature B in the injection process; after injection is completed, raising the reaction temperature to a temperature C, and stirring and refluxing; after the reaction is ended, separating the magnesium chloride through reduced pressure filtration, and removing the solvent through reduced pressure distillation of filtrate to obtain an organic metal film precursor; the method has the advantages of good safety in the preparation process, high yield, high product purity, high preparation efficiency and the like.

Description

Technical Field

[0001] The invention belongs to the field of semiconductors and relates to the preparation of an organic metal amine compound, in particular to a high-purity organic metal film precursor and a preparation method thereof. Background Art

[0002] "Oxide" is an important substrate in semiconductors, displays, etc., and has attracted much attention in various fields such as semiconductor devices, light-emitting diodes, and solar cells. In order to achieve high-definition resolution in the display field, transistor thin film materials with high charge carrier mobility are required as channels.

[0003] The channel region of existing thin-film transistors is mainly composed of amorphous silicon (α-Si). However, amorphous silicon (α-Si) is 0.5 cm2, which has low charge mobility and requires a high manufacturing process temperature of more than 350°C, so there are limitations in the realization of high-definition displays.

[0004] In order to achieve high-definition display, it is necessary to develop a new material to replace amorphous silicon (α-Si) used in the channel area of ​​​​thin film transistors. For example, thin film transistors using ZnO-based amorphous oxide semiconductors have high uniformity in terms of high charge mobility and electrical and optical properties. However, since zinc oxide thin films are very easy to crystallize during the deposition process, it is not easy to obtain an amorphous phase suitable for large-area orientation, and due to the presence of a crystalline particle system, there are disadvantages in the mobility of the device and the possibility of threshold voltage expansion problems. For example, a thin film transistor using amorphous InGaZnO (indium-gallium-zinc oxide; hereinafter referred to as IGZO) as an active layer is proposed. Active layers composed of IGZO can improve device performance because they have a thickness of about 10cm 2In order to manufacture IGZO thin films, IGZO targets are usually used for sputtering, but there are disadvantages that the composition of the thin film is not easy to control, and there is a problem of reduced device reliability. For example, the method of preparing IGZO thin films using atomic layer deposition (ALD) or chemical vapor deposition (CVD) processes using precursors has been emphasized. The composition of the IGZO thin film can be easily adjusted when the thin film is manufactured using the ALD or CVD process, and it has the advantage that the electrical properties of the transistor element can be fully expressed through a uniform film. The precursors for preparing IGZO thin films by ALD or CVD processes are usually trimethyl indium (hereinafter referred to as TMI), trimethyl gadolinium (hereinafter referred to as TMG), diethyl zinc (hereinafter referred to as DEZ), etc. Among them, precursors such as TMG and DEZ are liquid at room temperature. When preparing thin films by ALD or CVD through high vapor pressure, deposition of thin films is possible through uniform composition control and uniform precursor supply. However, in the case of TMI, there is an advantage of relatively high vapor pressure, but since it exists in solid form at room temperature, there are disadvantages such as particle problems and uniform precursor supply when preparing thin films by this process, which is relatively difficult.

[0005] Therefore, liquid indium and other group 13 organometallic precursors are needed, which are necessary in atomic layer deposition and CVD processes at room temperature and can suppress spontaneous combustion in moisture or air. To this end, [(3-dimethylamino)propyl]dimethylindium (hereinafter referred to as DADI) appears as a liquid indium precursor. The DADI precursor is liquid at room temperature and has a relatively high vapor pressure. Unlike alkyl organometallic precursors (TMG, TMI, DEZ, etc.) mainly used for IGZO thin film deposition, its spontaneous combustion in moisture or air is also suppressed, and its advantage is that it can be safely handled during the thin film manufacturing process.

[0006] However, the known preparation methods of DADI compounds involve the use of dangerous compounds such as alkali metal elements such as lithium, sodium, potassium, etc. or the use of aluminum sesquimers to prepare corresponding metal sesquimers, and the reaction process is relatively cumbersome and easily produces impurities that are difficult to separate, thereby reducing the yield. The above-mentioned preparation methods of DADI compounds require more steps to obtain starting materials, which leads to low preparation efficiency. Summary of the invention

[0007] Purpose of the invention: In order to overcome the deficiencies in the prior art, a high-purity organic metal thin film precursor and a preparation method thereof are provided, which have the advantages of good safety in the preparation process, high yield, high product purity and high preparation efficiency.

[0008] Technical solution: To achieve the above purpose, the present invention provides a high-purity organic metal film precursor, the structural expression of which is:

[0009]

[0010] Furthermore, an organic metal thin film precursor is obtained by reacting a metal halide with a prepared Grignard reagent, wherein:

[0011] The structural expression of metal halides is:

[0012]

[0013] Grignard reagent is a halogenated compound that reacts with magnesium metal in anhydrous ether or tetrahydrofuran to generate alkyl magnesium halide RMgX. This organomagnesium compound is called Grignard reagent.

[0014] The structural expression of the Grignard reagent is:

[0015]

[0016] The reaction formula is:

[0017]

[0018] Wherein, M is a Group 13 metal, which may 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 is one of hydrogen, alkyl (C 1-C 10), alkoxy (C 1-C 10), cycloalkyl (C 3-C 12) and heterocycloalkyl (C 3-C 12), which are independent of each other and may be further substituted by one or more substituents selected from halogen, trifluoromethyl, amino, cyano and hydroxy.

[0019] Furthermore, the organic metal film precursor is an organic metal amine compound, comprising the following structure:

[0020]

[0021] Further, the substituents of the alkyl and alkoxy groups include both straight-chain and branched forms and have 1 to 3 carbon atoms;

[0022] Alkoxy refers to a non-aromatic monocyclic or polycyclic system having 3 to 12 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl; polycyclic alkyl includes perhydronaphthyl, perhydroindenyl, etc.; bridged polycyclic alkyl includes adamantyl and norbornyl, etc.;

[0023] Heterocycloalkyl refers to a substituted or unsubstituted non-aromatic 3 to 12 membered ring radical consisting of carbon atoms and 1 to 5 heteroatoms selected from nitrogen, phosphorus, oxygen and sulfur, and the heterocyclochloroalkyl radical may be fused, bridged or may contain a spiro ring system, and the nitrogen, phosphorus, carbon, oxygen or sulfur atom in the heterocyclic ring may be oxidized in various oxidation states as appropriate.

[0024] The present invention also provides a method for preparing a high-purity organic metal thin film precursor, comprising the following steps:

[0025] S1: Under nitrogen protection, place metal halide in a flask, inject ether solvent, and cool to temperature A;

[0026] S2: Slowly inject methyl magnesium chloride into the flask within a set time, and control the reaction temperature not to exceed temperature B during this process;

[0027] S3: After the injection is completed, the reaction temperature is raised to temperature C and stirred under reflux;

[0028] S4: After the reflux is completed, the reaction solution is cooled to temperature A again, and the prepared Grignard reagent is slowly injected into the reaction solution, and the reaction temperature is controlled not to exceed temperature B during the injection process;

[0029] S5: After the injection is completed, the reaction temperature is raised to temperature C and stirred under reflux;

[0030] S6: After the reaction is terminated, the magnesium chloride is separated by vacuum filtration, and the solvent is removed by vacuum distillation of the filtrate to obtain an organic metal thin film precursor.

[0031] Furthermore, in step S1, the metal halide is indium trichloride, the ether solvent is diethyl ether, and the temperature A is 0°C to 10°C.

[0032] Furthermore, in step S2, the time is set to 28 to 32 minutes and the temperature B is set to 30°C.

[0033] Furthermore, in step S3 and step S5, the temperature C is 35° C., and the stirring and reflux time is 12 hours.

[0034] Furthermore, in step S4, the Grignard reagent is an alkyl magnesium halide, and the preparation method is: reacting the halide with metal magnesium in anhydrous ether or tetrahydrofuran to generate the alkyl magnesium halide RMgX. The Grignard reagent can be used in an amount of 2.0 to 2.5 moles.

[0035] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0036] 1. The entire preparation process avoids the use of dangerous compounds such as lithium, sodium, potassium, etc., ensuring the safety of the preparation process.

[0037] 2. Through the application of Grignard reagent, the raw material equivalent, addition rate and system reaction temperature are precisely controlled during the preparation process to reduce impurities and effectively improve the yield and purity.

[0038] 3. A one-pot reaction method is realized, the reaction time of the preparation process is shortened, and the overall preparation efficiency is significantly improved.

[0039] 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, which is convenient and safe. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is the H-NMR chart of [3-(dimethylamino)propyl]dimethylindium prepared in Example 1. DETAILED DESCRIPTION

[0041] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0042] The present invention provides a high-purity organic metal film precursor, the structural expression of which is:

[0043]

[0044] The organic metal thin film precursor is obtained by reacting the metal halide with the prepared Grignard reagent, wherein:

[0045] The structural expression of metal halides is:

[0046]

[0047] Grignard reagent is a halogenated compound that reacts with magnesium metal in anhydrous ether or tetrahydrofuran to generate alkyl magnesium halide RMgX. This organomagnesium compound is called Grignard reagent.

[0048] The structural expression of the Grignard reagent is:

[0049]

[0050] The reaction formula is:

[0051]

[0052] Wherein, M is a Group 13 metal, which may 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 is one of hydrogen, alkyl (C 1-C 10), alkoxy (C 1-C 10), cycloalkyl (C 3-C 12) and heterocycloalkyl (C 3-C 12), which are independent of each other and may be further substituted by one or more substituents selected from halogen, trifluoromethyl, amino, cyano and hydroxy.

[0053] The organic metal film precursor is an organic metal amine compound, including the following structure:

[0054]

[0055] Alkyl and alkoxy substituents include both straight-chain and branched forms and have 1 to 3 carbon atoms;

[0056] Alkoxy refers to a non-aromatic monocyclic or polycyclic system having 3 to 12 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl; polycyclic alkyl includes perhydronaphthyl, perhydroindenyl, etc.; bridged polycyclic alkyl includes adamantyl and norbornyl, etc.;

[0057] Heterocycloalkyl refers to a substituted or unsubstituted non-aromatic 3 to 12 membered ring radical consisting of carbon atoms and 1 to 5 heteroatoms selected from nitrogen, phosphorus, oxygen and sulfur, and the heterocyclochloroalkyl radical may be fused, bridged or may contain a spiro ring system, and the nitrogen, phosphorus, carbon, oxygen or sulfur atom in the heterocyclic ring may be oxidized in various oxidation states as appropriate.

[0058] The present invention also provides a method for preparing a high-purity organic metal thin film precursor, comprising the following steps:

[0059] S1: Under nitrogen protection, place metal halide in a flask, inject ether solvent, and cool to temperature A;

[0060] The metal halide is indium trichloride, the ether solvent is diethyl ether, and the temperature A is 0°C to 10°C.

[0061] S2: Slowly inject methyl magnesium chloride into the flask within a set time, and control the reaction temperature not to exceed temperature B during this process;

[0062] Set the time to 28 to 32 minutes and the temperature B to 30°C;

[0063] S3: After the injection is completed, the reaction temperature is raised to temperature C and stirred under reflux; the temperature C is 35°C and the stirring and reflux time is 12 hours;

[0064] S4: After the reflux is completed, the reaction solution is cooled to temperature A again, and the prepared Grignard reagent is slowly injected into the reaction solution, and the reaction temperature is controlled not to exceed temperature B during the injection process;

[0065] Alkyl magnesium halide, specifically 3-(dimethylamino)propylmagnesium chloride; 2.0 to 2.5 moles of Grignard reagent can be used;

[0066] S5: After the injection is completed, the reaction temperature is raised to temperature C and stirred under reflux; the temperature C is 35° C. and the stirring and reflux time is 12 hours;

[0067] S6: After the reaction is terminated, the magnesium chloride is separated by vacuum filtration, and the solvent is removed by vacuum distillation of the filtrate to obtain an organic metal thin film precursor.

[0068] Based on the above scheme, the scheme of the present invention is applied as an example, and the organic metal film precursor is an organic methylamine compound, specifically [3-(dimethylamino)propyl]dimethylindium (DADI), as follows:

[0069] Embodiment 1:

[0070] Under nitrogen protection, 50g (1eq) of indium trichloride was placed in a flask and injected with 300 ml of ether. Then cooled to 10°C. 137g (2eq) of methylmagnesium chloride was slowly injected over a period of 30 minutes, at which point the reaction temperature did not exceed 30°C. After the injection was complete, it was raised to 35°C and stirred at reflux for 12 hours. After the reflux was complete, the reaction solution was cooled to 10°C again, and 115 grams (1 equivalent) of 3-(dimethylamino)propylmagnesium chloride was slowly injected, being careful not to exceed 30°C. After the injection was complete, it was raised to 35°C and stirred at reflux 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. In order to improve the purity, vacuum distillation (44°C. / 2.2Torr) was performed to obtain 48 grams (yield 92%) of DADI liquid.

[0071] like Figure 1 As shown, HNMR (C6D6): δ-0.13 (s, 6H), 0.65 (t, 2H), 1.70 (tt, 2H), 1.76 (s, 6H), 1.78 (t, 2H). The performance of DADI liquid was verified.

[0072] Embodiment 2:

[0073] Under nitrogen protection, 50g (1eq) of indium trichloride was placed in a flask and injected with 300 ml of ether. Then cooled to 0°C. 137g (2eq) of methylmagnesium chloride was slowly injected over a period of 28 minutes, at which point the reaction temperature did not exceed 30°C. After the injection was complete, it was raised to 35°C and stirred at reflux for 12 hours. After the reflux was complete, the reaction solution was cooled to about 0°C again, and 115 grams (1 equivalent) of 3-(dimethylamino)propylmagnesium chloride was slowly injected, being careful not to exceed 30°C. After the injection was complete, it was raised to 35°C and stirred at reflux 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. In order to improve the purity, vacuum distillation (44°C. / 2.2Torr) was performed to obtain 46 grams (yield 88%) of DADI liquid.

[0074] Embodiment 3:

[0075] Under nitrogen protection, 50g (1eq) of indium trichloride was placed in a flask and injected with 300 ml of ether. Then cooled to 5°C. 171g (2eq) of methylmagnesium chloride was slowly injected over a period of 32 minutes, at which point the reaction temperature did not exceed 30°C. After the injection was complete, it was raised to 35°C and stirred at reflux for 12 hours. After the reflux was complete, the reaction solution was cooled to 5°C again, and 115 grams (1 equivalent) of 3-(dimethylamino)propylmagnesium chloride was slowly injected, being careful not to exceed a reaction temperature of 30°C. After the injection was complete, it was raised to 35°C and stirred at reflux 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. In order to improve the purity, vacuum distillation (44°C. / 2.2Torr) was performed to obtain 36 grams (yield 84%) of DADI liquid.

[0076] Comparative Example 1:

[0077] In this comparative example, the preparation methods of Examples 1 to 3 are compared and analyzed with the existing DADI compound preparation method and product, as shown in the following table:

[0078] Preparation method Yield purity Existing methods 70％ 98％ Example 1 92％ 99.5％ Example 2 88％ 99.6％ Example 3 84％ 99.4％

[0079] As can be seen from the above table, the methods of Examples 1 to 3 are significantly superior to the existing methods for preparing DADI compounds in terms of both yield and purity, which verifies the effectiveness and practical effects of the present invention.

Claims

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

2. A high-purity organic metal thin film precursor according to claim 1, characterized in that: The organic metal thin film precursor is obtained by reacting the metal halide with the prepared Grignard reagent, wherein: The structural expression of metal halides is: The structural expression of the Grignard reagent is: The reaction formula is: Wherein, M is a Group 13 metal, X is a halogen, n is an integer from 1 to 9; R1, R3, R 11 , R 12 is one of hydrogen, alkyl, alkoxy, cycloalkyl and heterocycloalkyl, independently of each other.

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

4. A high-purity organic metal 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 3 carbon atoms; Alkoxy refers to a non-aromatic monocyclic or polycyclic ring system having 3 to 12 carbon atoms, including cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl; Heterocycloalkyl refers to a substituted or unsubstituted non-aromatic 3 to 12 membered ring radical consisting of carbon atoms and 1 to 5 heteroatoms selected from nitrogen, phosphorus, oxygen and sulfur.

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

6. The method for preparing a high-purity organic metal 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°C to 10°C.

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

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

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

10. The method for preparing a high-purity organic metal thin film precursor according to claim 9, characterized in that: The preparation method of the Grignard reagent in step S4 is: reacting the halide with metal magnesium in anhydrous ether or tetrahydrofuran to generate alkyl magnesium halide RMgX.

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