Method for oxygen removal from alkyl metal precursors

Abstract

The application discloses an oxygen removal method of alkyl metal precursors, comprising the following steps: contacting the alkyl metal precursors containing oxygen impurities with selected metals, and heating the reaction to reduce the oxygen impurities; the standard hydrogen reduction potential of the selected metal magnesium is-2.37V. The oxygen removal method provided by the application can realize good oxygen removal and purification effect by reacting the metal magnesium with the oxygen-containing components, and then heating and stirring, so that stable low-oxygen alkyl metal precursors are obtained, the inorganic purity of which reaches 99.9999%, and the oxygen content is less than 5ppm. The metal element potential sequence in the alkyl metal precursors is relatively low, which can significantly improve the impurity removal reaction rate. The chemical properties of the metal element are stable, and the metal element can be recycled and reused. The process flow of the application is simple, new impurities are not introduced, the treatment efficiency and impurity removal efficiency are relatively high, the operation is convenient, and the application prospect is very wide.

Description

Technical Field

[0001] This invention relates to the field of semiconductor material preparation technology, and in particular to a method for deoxygenating alkyl metal precursors. Background Technology

[0002] Organometallic compounds are common precursors in materials preparation, especially in the growth of semiconductor thin films or structures. For example, trimethylaluminum (TMA) is an important raw material for growing optoelectronic materials in metal-organic vapor deposition (MOCVD) and chemical beam epitaxy (CBE). It is mainly used for the growth of epitaxial wafers of AlGaN / AlN-based group III nitride semiconductor materials, and is a core raw material for growing third-generation semiconductors such as AlGaN and AlN. Furthermore, it is also one of the core raw materials for phase-change memories, radio frequency integrated circuit chips, and other related applications.

[0003] The quality of compound semiconductor materials epitaxially grown using trimethylaluminum as a precursor is primarily affected by impurities within the trimethylaluminum itself. Due to the nature of the trimethylaluminum preparation process, organic oxygen impurities are introduced during the synthesis stage. These organic oxygen impurities typically have vapor pressures higher or similar to those of trimethylaluminum. Therefore, during the production of compound semiconductor materials, oxygen atoms can bind within the semiconductor thin layer, leading to a chain reaction that severely degrades the quality and lifetime of downstream wafers, ultimately affecting the performance of the compound semiconductor. Aluminum oxide impurities in trimethylaluminum, due to their similar boiling points to the product, are difficult to purify using conventional distillation equipment. New impurity removal methods must be employed to remove these oxygen impurities and purify the precursor.

[0004] Existing technologies provide various purification methods. For example, current technologies employ complexation to remove oxygen-containing components from trimethylaluminum. Furthermore, Japanese Patent Publication No. 112991 / 1991 (JP-A-3-112991) proposes a method for purifying alkylaluminum containing oxygen-containing components, wherein the oxygen-containing components are treated with aluminum halides such as aluminum bromide or aluminum iodide. Japanese Patent Publication No. JP31338893(43) proposes a method using alkali metal halides to react with the oxygen-containing components. A complex is formed, and then deoxygenation is achieved through distillation; Chinese invention patent CN1749260B proposes a method of deoxygenation by adding sodium; Chinese invention patent CN1769289B proposes a method of deoxygenation by purging trimethylaluminum vapor with an inert gas (such as high-purity helium); Chinese invention patent CN109879900A proposes a method of reducing oxygen impurities in trimethylaluminum by using inorganic salts; US patent US4797500 proposes a method of removing oxygen impurities by adding a potassium-sodium alloy and refluxing.

[0005] Various existing methods for deoxygenation and purification of MO sources all have some technical problems. For example, some existing technologies use complexation methods for deoxygenation, but this method is complex, requires high temperatures for decomposition, and may introduce new impurities. Some existing technologies use aluminum halide reagents, which themselves have a high tendency to decompose into water, and halogens may increase the risk of corrosion in stainless steel reactors. Some existing technologies propose using alkali metal halides to react with oxygen-containing components to form complexes, followed by distillation to achieve deoxygenation, but this method requires the use of other solvents to treat the mixture, making the process complex. Some existing technologies propose using inert gases (such as high-purity helium) to purge trimethylaluminum vapor for purification, but this method causes some trimethylaluminum vapor to be carried away by the inert gas. The loss of trimethylaluminum along with volatile gases increases the need for additional safety procedures in the exhaust gas treatment process. Some existing technologies employ a sodium reflux deoxygenation method, where a portion of the trimethylaluminum reacts with metallic sodium at high temperatures to produce sodium tetramethylaluminum, resulting in further trimethylaluminum loss. Other technologies utilize inorganic salts to reduce oxygen impurities in trimethylaluminum, but this requires a second, prolonged vacuum treatment of the treated product, extending the production cycle. Some technologies propose a potassium-sodium alloy reflux purification method, but this method results in the potassium-sodium alloy forming large particles within the trimethylaluminum, hindering its complete dispersion and preventing effective contact. This ultimately affects the product's impurity removal efficiency, and the trimethylaluminum and potassium-sodium alloy readily react at high temperatures, further contributing to trimethylaluminum loss.

[0006] Therefore, developing a precursor deoxygenation method with high processing rate, high deoxygenation efficiency, convenient operation, and recyclability is of great significance for the mass production of precursors. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a method for deoxygenating alkyl metal precursors.

[0008] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0009] The present invention provides a method for removing oxygen from an alkyl metal precursor, comprising: contacting and reacting an alkyl metal precursor containing oxygen impurities with a selected metal to at least remove the oxygen impurities; wherein the standard hydrogen reduction potential of the selected metal is approximately -2.37V, for example -2.35 to -2.40V.

[0010] Based on the above technical solution, compared with the prior art, the beneficial effects of the present invention include at least the following:

[0011] The deoxygenation method provided by this invention involves reacting a selected elemental metal with an oxygen-containing component, followed by heating and stirring to achieve deoxygenation and obtain stable low-oxygen trimethylaluminum with an inorganic purity of 99.9999% and an oxygen content of <5ppm. The preferred selected metal, magnesium, has a standard hydrogen reduction potential of -2.37V. The preferred alkyl metal precursors include trimethylaluminum and trimethylgallium, with aluminum having a standard hydrogen reduction potential of -1.66V and gallium a standard hydrogen reduction potential of -0.32V. In summary, magnesium plays a role in reducing and transferring oxygen impurities in the two alkyl metal precursors, improving the deoxygenation reaction rate. Furthermore, the selected metal is chemically stable and can be recycled and reused. The process is simple, does not introduce new impurities, has high processing and deoxygenation efficiency, and is easy to operate, showing great promise for widespread application.

[0012] The above description is merely an overview of the technical solution of the present invention. In order to enable those skilled in the art to better understand the technical means of this application and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described below. Detailed Implementation

[0013] In view of the shortcomings of the prior art, the inventors of this invention, through long-term research and extensive practice, have proposed the technical solution of this invention. The following will further explain and illustrate this technical solution, its implementation process, and its principles.

[0014] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0015] Moreover, relational terms such as “first” and “second” are used merely to distinguish one component or method step from another that has the same name, and do not necessarily require or imply any such actual relationship or order between these components or method steps.

[0016] This invention provides a method for deoxygenating an alkyl metal precursor, comprising the following steps:

[0017] An alkyl metal precursor containing oxygen impurities is brought into contact with a selected metal and heated to react, thereby reducing the oxygen impurities. The standard hydrogen reduction potential of the selected magnesium metal is -2.37V. Of course, the standard hydrogen reduction potential of the magnesium metal used may fluctuate to some extent due to the different contents of impurity elements. This is a normal phenomenon. That is, the present invention preferably uses pure magnesium metal as a reducing agent and catalyst, but it does not exclude the possibility that the magnesium metal used contains other alloying elements or doping elements.

[0018] In this invention, the reducing properties of selected metal Mg for oxygen atom removal are utilized. While existing technologies also employ reducing agents to reduce oxygen atom, such as pretreatment with borohydrides, the inventors of this invention have discovered that in these prior art, borohydrides merely act as reducing agents. In contrast, the selected metal surface used in this invention has a lower metal potential order, making oxidized alkyl aluminum unstable. Oxygen atom atoms then transfer to the surface of the selected metal, resulting in a superior reaction rate and improved impurity removal efficiency. Furthermore, Mg can be recycled and reused, exhibiting excellent reusability.

[0019] Regarding the specific processing ratio, in some embodiments, the mass ratio of the alkyl metal precursor to the selected metal is 1-100:1;

[0020] In some implementations, the macroscopic morphology of the selected metal may include any one or a combination of two or more of the following: powder, network, and sheet. While reduction can also be achieved using bulk materials, the specific surface area of ​​bulk materials is relatively low; therefore, the preferred morphology is still the one with a larger specific surface area as described above.

[0021] In some implementations, the deoxygenation method may specifically include the following steps:

[0022] The alkyl metal precursor is mixed with a selected metal to obtain a mixture;

[0023] The mixture is heated and stirred at a selected temperature to obtain a deoxygenated alkyl metal precursor;

[0024] Regarding specific operating conditions, in some implementations, the selected temperature is 80–127°C, and the heating and stirring time is 1–10 hours; in some implementations, the deoxygenation method further includes:

[0025] The step of surface activation treatment of the selected metal before it comes into contact with the alkyl metal precursor.

[0026] In some embodiments, the surface activation treatment includes at least contacting the selected metal with an acidic reagent to at least remove oxides from the surface of the selected metal.

[0027] In addition to achieving the aforementioned reduction and oxygen transfer, the technical solution provided by this invention has the advantage that the selected reducing agent can be reused. This is manifested in the fact that, in some embodiments, the deoxygenation method further includes the steps of cleaning the remaining selected metal after deoxygenation with an organic solvent and reusing the surface activation treatment.

[0028] As some typical application examples of the above technical solutions, the above technical solutions can be implemented through the following specific processes:

[0029] Step 1: Selection and Pretreatment of Metallic Elements

[0030] Magnesium powder (100-300 mesh diameter) / mesh / sheets were selected. The selected powder / mesh / sheets were placed in a 100-1000 ml dry conical flask, and 20-400 ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 5-20 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0031] Step 2: Treatment of trimethylaluminum with elemental metals

[0032] Each kg of elemental metal can process 1–100 kg of trimethylaluminum, and the processing method is as follows:

[0033] Method: Under the protection of inert gas in a glove box, the pretreated metal powder / mesh / sheet was mixed with trimethylaluminum in a flask and stirred. The stirring speed was set to 20-500 r / min. After heating the internal temperature to 80-120℃, the mixture was stirred for 1-10 h.

[0034] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0035] The collected products were tested using a nuclear magnetic resonance spectrometer. If the oxygen content was less than 5 ppm, the product was considered qualified.

[0036] Step 4: Recovery of elemental metals

[0037] Under the protection of inert gas in a glove box, the used metal powder / mesh / sheet is placed in a glass dish and soaked with 5 to 50 times its weight of tri-n-octylamine. After standing for 5 to 20 hours, it is filtered with a sand filter. The filtered metal powder / mesh / sheet is then washed with 5 to 50 times its weight of ethanol, dried, and stored in a desiccator for use after the next activation.

[0038] Regarding better application results, in some embodiments, the oxygen content of the deoxygenated alkyl metal precursor can be, for example, below 5 ppm. Of course, if the requirements for product purity are not very stringent, the reaction time can be appropriately shortened to obtain a product with a slightly higher oxygen content. This is still within the scope of the present invention and is not limited to the absolute requirement of reducing the oxygen content of the product to the above-mentioned value.

[0039] The technical solution of the present invention will be further described in detail below through several embodiments. However, the selected embodiments are only used to illustrate the present invention and do not limit the scope of the present invention.

[0040] Furthermore, due to the physicochemical properties of trimethylaluminum—exploding upon contact with water and spontaneously combusting upon contact with air—all work involved in this invention is conducted in an inert gas atmosphere such as nitrogen or argon, strictly eliminating environmental factors such as air and moisture. All experimental instruments used are cleaned according to strict cleaning standards to eliminate the influence of contamination on the test results. Of course, these are common techniques for handling related substances, and the raw materials involved, such as the synthesized trimethylaluminum or the metals used, can all be obtained through conventional methods or are commercially available.

[0041] Example 1

[0042] This embodiment illustrates a process for preparing high-purity trimethylaluminum, as detailed below:

[0043] Step 1: Selection and Pretreatment of Metallic Elements

[0044] 50g of magnesium mesh was selected as the oxygen removal agent. The 50g magnesium mesh was placed in a 500ml dry conical flask, and 300ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 20 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0045] Step 2: Treatment of trimethylaluminum with elemental metals

[0046] Under the protection of inert gas in a glove box, 50g of pretreated magnesium mesh was added to 2L of trimethylaluminum containing 1000g, and heated at 120℃ for 1h with a stirring speed of 60r / min. Samples were taken after the heating was completed.

[0047] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0048] The deoxygenated trimethylaluminum was detected using nuclear magnetic resonance spectroscopy, and the analysis results are listed in Table 1.

[0049] Table 1

[0050] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 17.2 1.2

[0051] Step 4: Recovery of elemental metals

[0052] Place 50g of used magnesium mesh in a glass dish, add 100g of tri-n-octylamine and mix well. Stir for 10 minutes, then let stand for 15 hours. After that, filter with a sand filter. Wash the filtered magnesium mesh with 1000g of ethanol, dry it, and store it in a desiccator for use after the next activation.

[0053] Example 2

[0054] Step 1: Selection and Pretreatment of Metallic Elements

[0055] 50g of magnesium mesh was selected as the oxygen removal agent. The 50g magnesium mesh was placed in a 500ml dry conical flask, and 300ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 20 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0056] Step 2: Treatment of trimethylaluminum with elemental metals

[0057] Under the protection of inert gas in a glove box, 50g of pretreated magnesium mesh was added to 2L of trimethylaluminum containing 1000g, and heated at 100℃ for 1h with a stirring speed of 60r / min. Samples were taken after the heating was completed.

[0058] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0059] The deoxygenated trimethylaluminum was detected using nuclear magnetic resonance spectroscopy, and the analysis results are listed in Table 2.

[0060] Table 2

[0061] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 17.2 5.4

[0062] Step 4: Recovery of elemental metals

[0063] Place 50g of used magnesium mesh in a glass dish, add 100g of tri-n-octylamine and mix well. Stir for 10 minutes, then let stand for 15 hours. After that, filter with a sand filter. Wash the filtered magnesium mesh with 1000g of ethanol, dry it, and store it in a desiccator for use after the next activation.

[0064] Example 3

[0065] Step 1: Selection and Pretreatment of Metallic Elements

[0066] 50g of magnesium mesh was selected as the oxygen removal agent. The 50g magnesium mesh was placed in a 500ml dry conical flask, and 300ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 20 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0067] Step 2: Treatment of trimethylaluminum with elemental metals

[0068] Under the protection of inert gas in a glove box, 50g of pretreated magnesium mesh was added to 2L of trimethylaluminum containing 1000g, and heated at 80℃ for 1h with a stirring speed of 60r / min. Samples were taken after the heating was completed.

[0069] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0070] The deoxygenated trimethylaluminum was detected using nuclear magnetic resonance spectroscopy, and the analysis results are listed in Table 3.

[0071] Table 3

[0072] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 17.2 3.4

[0073] Step 4: Recovery of elemental metals

[0074] Place 50g of used magnesium mesh in a glass dish, add 100g of tri-n-octylamine and mix well. Stir for 10 minutes, then let stand for 15 hours. After that, filter with a sand filter. Wash the filtered magnesium mesh with 1000g of ethanol, dry it, and store it in a desiccator for use after the next activation.

[0075] Example 4

[0076] Step 1: Selection and Pretreatment of Metallic Elements

[0077] 50g of magnesium mesh was selected as the oxygen removal agent. The 50g magnesium mesh was placed in a 500ml dry conical flask, and 300ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 20 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0078] Step 2: Treatment of trimethylaluminum with elemental metals

[0079] Under the protection of inert gas in a glove box, 50g of pretreated magnesium mesh was added to 2L of trimethylaluminum containing 1000g, and heated at 80℃ for 8h with a stirring speed of 60r / min. Samples were taken after the heating was completed.

[0080] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0081] The deoxygenated trimethylaluminum was detected using nuclear magnetic resonance spectroscopy, and the analysis results are listed in Table 4.

[0082] Table 4

[0083] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 17.2 2.0

[0084] Step 4: Recovery of elemental metals

[0085] Place 50g of used magnesium mesh in a glass dish, add 100g of tri-n-octylamine and mix well. Stir for 10 minutes, then let stand for 15 hours. After that, filter with a sand filter. Wash the filtered magnesium mesh with 1000g of ethanol, dry it, and store it in a desiccator for use after the next activation.

[0086] The above-mentioned magnesium mesh showed a decrease in deoxygenation efficiency of only 4% after being reused three times.

[0087] Comparative Example 1

[0088] Step 1: Selection and Pretreatment of Metallic Elements

[0089] 10g of aluminum powder (standard hydrogen reduction potential of aluminum is -1.66V, diameter is 250-300 mesh) was selected as the oxygen removal agent. The 10g aluminum powder was placed in a 100ml dry conical flask, and 50ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 10 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0090] Step 2: Treatment of trimethylaluminum with elemental metals

[0091] Under the protection of inert gas in a glove box, 10g of pretreated aluminum powder and 100g of trimethylaluminum were added to a 2L flask, and the mixture was gradually heated to 120°C. The mixture was stirred for 1 hour at a stirring speed of 60r / min, and then samples were taken for testing.

[0092] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0093] The collected trimethylaluminum was analyzed using nuclear magnetic resonance spectroscopy, and the results of the middle fraction analysis are listed in Table 5.

[0094] Table 5

[0095] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 17.2 17.8

[0096] This comparative example illustrates that not all reducing metals can effectively remove oxygen impurities from trimethylaluminum; therefore, the selected metal must be chosen carefully.

[0097] Comparative Example 2

[0098] Step 1: Selection and Pretreatment of Metallic Elements

[0099] Magnesium mesh is used as an oxygen remover. Place 10g of magnesium mesh in a 500ml dry conical flask, add 300ml of an acetone-concentrated hydrochloric acid (1:1) mixture, stir vigorously for 20 minutes, and then filter through a sintered glass filter. Repeat this process twice, then wash with acetone and anhydrous ether, dry under vacuum, and store in a desiccator.

[0100] Step 2: Treatment of trimethylaluminum with elemental metals

[0101] Under the protection of inert gas in a glove box, 10g of pretreated magnesium mesh was added to 2L of trimethylaluminum containing 1000g, and heated at 120℃ for 10h with a stirring speed of 60r / min. Samples were taken after the heating was completed.

[0102] Step 3: Oxygen content detection of trimethylaluminum after deoxygenation

[0103] The collected middle fraction was analyzed using nuclear magnetic resonance spectroscopy, and the results are listed in Table 6.

[0104] Table 6

[0105] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 17.2 8.7

[0106] Step 4: Recovery of elemental metals

[0107] Place 10g of used magnesium mesh in a glass dish, add 100g of tri-n-octylamine and mix well. Stir for 10 minutes, then let stand for 15 hours. After that, filter with a sand filter. Wash the filtered magnesium mesh with 1000g of ethanol, dry it, and store it in a desiccator for use after the next activation.

[0108] This comparative example illustrates that the selected ratio range of the metal to trimethylaluminum has a significant impact on obtaining a better impurity removal effect, and the amount of the selected metal should be carefully controlled in practical applications.

[0109] Comparative Example 3

[0110] This embodiment also illustrates a method for preparing high-purity trimethylaluminum, which is largely the same as in Example 1, except that:

[0111] The reducing agent is replaced with borohydride, specifically:

[0112] Commercially available sodium borohydride was selected as the reducing agent. 100g of sodium borohydride was weighed and placed in an oven for heating and drying at 100℃ for 10 hours. At the same time, a vacuum pump was used to pressurize the cylinder to 1-5 kPa and maintain it for 30 minutes. Then, nitrogen gas was added through the pipeline to bring the pressure back to normal. This process was repeated 5 times to obtain the reducing agent.

[0113] The reducing agent has the same particle size and specific surface area as in Example 1, and after being mixed with trimethylaluminum in the same proportion as in Example 1, it is subjected to the same treatment process and condition parameters for impurity removal.

[0114] Finally, it was found that achieving the same oxygen content required 5 hours of heating and stirring, which was significantly longer than in Example 1, and sodium borohydride was more difficult to recover and reuse. The selected metal provided by this invention has good reusability.

[0115] Example 5

[0116] This embodiment also demonstrates the use of a magnesium mesh as an oxygen scavenger for the removal of oxygen from trimethylgallium, as shown below:

[0117] Step 1: Selection and Pretreatment of Metallic Elements

[0118] 50g of magnesium mesh was selected as the oxygen removal agent. The 50g magnesium mesh was placed in a 500ml dry conical flask, and 300ml of an acetone-concentrated hydrochloric acid (1:1) mixed solvent was added. The mixture was stirred vigorously for 20 minutes, followed by filtration through a sintered glass filter. This process was repeated twice. The flask was then washed with acetone and anhydrous ether, dried under vacuum, and stored in a desiccator.

[0119] Step 2: Treatment of trimethylgallium with elemental metals

[0120] Under the protection of inert gas in a glove box, 50g of pretreated magnesium mesh was added to 2L of trimethylgallium containing 1000g, and heated at 50℃ for 1h with a stirring speed of 60r / min. Samples were taken after the process was completed.

[0121] Step 3: Detection of oxygen content in trimethylgallium after deoxygenation

[0122] The deoxygenated trimethylaluminum was detected using nuclear magnetic resonance spectroscopy, and the analysis results are listed in Table 7.

[0123] Table 7

[0124] Before deoxygenation (ppm) After deoxygenation (ppm) oxygen-containing components 46 4.3

[0125] In addition, the inventors of this invention also conducted deoxygenation tests on other alkyl metal precursors, such as compounds of triethyl, monomethyldiethyl, or dimethylmonoethyl, and achieved good technical results.

[0126] Based on the above embodiments and comparative examples, it is clear that the embodiments of the present invention can prepare low-oxygen trimethylaluminum / trimethylgallium. This is achieved by first pretreating the selected metal element powder / mesh / sheet, then mixing the pretreated metal element powder / mesh / sheet with trimethylaluminum and heating. This method yields stable low-oxygen trimethylaluminum with an inorganic purity of 99.9999% and an oxygen content of <5ppm. Finally, the used metal element powder / mesh / sheet is recycled. The present invention achieves deoxygenation and purification by reacting the metal element with the oxygen-containing component and heating and stirring. The process of the present invention is simple, does not introduce new impurities, and the metal element used is chemically stable and recyclable.

[0127] It should be understood that the above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for deoxygenating alkyl metal precursors, characterized in that, include: A surface activation treatment is performed on a selected metal, the surface activation treatment comprising at least contacting the selected metal with an acidic reagent to at least remove oxides from the surface of the selected metal; An alkyl metal precursor containing oxygen impurities is contacted with and reacted with a selected metal to at least remove the oxygen impurities; The selected metal is elemental magnesium with a standard hydrogen reduction potential of -2.35 to -2.40 V, and the alkyl metal precursor is selected from trimethylaluminum or trimethylgallium.

2. The deoxygenation method according to claim 1, characterized in that, The mass ratio of the alkyl metal precursor to the selected metal is 1-100:1; And / or, the macroscopic morphology of the selected metal includes any one or a combination of two or more of the following: powder, network, and sheet.

3. The deoxygenation method according to claim 1, characterized in that, Specifically, it includes: The alkyl metal precursor is mixed with a selected metal to obtain a mixture; The mixture is heated and stirred at a selected temperature to obtain a deoxygenated alkyl metal precursor.

4. The deoxygenation method according to claim 3, characterized in that, The selected temperature is 80~127℃, and the heating and stirring time is 1-10h.

5. The deoxygenation method according to claim 1, characterized in that, It also includes the steps of cleaning the selected metal remaining after deoxygenation with an organic solvent and reusing it after the surface activation treatment.

6. The deoxygenation method according to claim 1, characterized in that, The oxygen content of the deoxygenated alkyl metal precursor is less than 5 ppm.