CN1171894C - Preparation method of oxygen-free trialkylgallium - Google Patents

Abstract

The invention discloses a method for preparing oxygen-free trialkylgallium. The preparation method comprises: placing an organic tertiary amine and a mixture of gallium and magnesium in a reaction vessel, removing the air in the system and filling it with an inert gas; After the addition, continue to stir until the reaction is complete; or add a hydrocarbon solvent, add the haloalkane under stirring and heating, and continue to stir until the reaction is complete after the addition; remove excess organic tertiary amine and solvent under reduced pressure And volatile substances, normal pressure or reduced pressure distillation to obtain the mixture of trialkylgallium and amine, or directly carry out complex decomposition to obtain trialkylgallium. The advantage of the invention is that under the condition that the organic tertiary amine is used as an oxygen-free auxiliary reagent, and with the assistance of other metals, the direct action of halide methane and metal gallium can be realized to generate trialkylgallium. The yield is above 30%. The method realizes the anaerobic preparation of the trialkylgallium compound and is easy to operate.

Description

Preparation method of oxygen-free trialkylgallium

1. Technical field

The invention relates to a method for preparing trialkylgallium used in the field of optoelectronic technology, in particular to a method for preparing oxygen-free trialkylgallium.

2. Background technology

High-purity trialkylgallium is one of the important supporting materials for the epitaxial growth of compound semiconductors by advanced metal organic chemical vapor deposition (MOCVD) technology. It is widely used in the growth of GaAs, GaN, AlGaAs, GaInN and other compound semiconductor materials. It emits light at high brightness It has important application value in the development and production of optoelectronic devices such as tubes, semiconductor lasers, detectors of various wavelengths, and solar cells.

The quality and purity of high-purity trialkylgallium is the most important quality index of high-purity trialkylgallium source. The quality and purity of high-purity trialkylgallium directly affect the performance of the grown compound semiconductor. With the rapid development of MOCVD technology With the acceleration of development and industrialization, higher and higher requirements are put forward for trialkylgallium sources. The quality and purity of high-purity trialkylgallium is mainly related to the amount of elemental impurities contained in it. The lower the content of elemental impurities, the better the quality of high-purity trialkylgallium. For a long time, metal impurities such as iron, silicon, copper, and tin have paid the most attention to trialkylgallium sources. Recent studies have shown that oxygen is one of the most important impurity elements affecting the performance of compound semiconductor materials, and the use of oxygen-containing solvents in the source preparation process is an important reason for oxygen contamination of the epitaxial layer [M.S.Ravetz, L.M.Smith, S.A. Rushworth, A.B. Leese, R. Kanijola, J.I. Davies, R.T. Blunt, J. Electron. Mater., 2000, 29, 157. (Journal of Electronic Materials, 2000)].

At present, the preparation methods of trialkylgallium with industrial application value mainly include Grignard reagent method and direct alkylation method. Using the obtained Grignard reagent to react with gallium halide to obtain an alkylation product; the direct alkylation method is to realize the alkylation of halogenated hydrocarbons to metal gallium in one step with the assistance of metal reagents. These two methods usually require organic ethers such as diethyl ether as the reaction medium and auxiliary reagents. Studies have shown that the organic ether reagents used in the preparation process are difficult to completely remove during the purification process, and a small amount of residual organic ether reagents will cause oxygen contamination of the compound, thereby affecting the performance of compound semiconductors. For this reason, the concept of low-oxygen source and oxygen-free source has been proposed recently. The so-called low-oxygen source is to try to solve the problem from the purification process, and use purification technology (such as complex purification technology) to remove the organic ethers that may exist in the source. Oxygen-containing impurities such as; the so-called oxygen-free source means that from the initial product preparation process of the source, the use of aerobic reagents is excluded, and in a completely anaerobic system

Realize the preparation and purification of source compounds, and completely eliminate the contamination of sources by oxygen-containing impurities such as organic ethers. From the perspective of ensuring and improving the quality of the source, an oxygen-free source should be the most ideal. Document [ACJones, SARushworth, T.Martin, TJWhittaker, RWFreer, US Patent 5,980,978 (1999) (US Patent, Patent No. 5,980,978, 1999)] reported utilizing Grignard reagent method to prepare trialkylgallium under anaerobic conditions The method is to prepare an alkyl Grignard reagent through the action of metal magnesium and an alkyl halide in the presence of an organic tertiary amine, and then react the obtained Grignard reagent with gallium trichloride to obtain trialkyl gallium and amine A mixture of complexes. This preparation method needs to prepare the Grignard reagent and gallium trichloride first, and then allow the two to react. In fact, three-step reactions are required, which obviously has the disadvantage of troublesome operation. In addition, the yield of the reaction is not high. Considering the production yield of gallium trichloride, the production yield is relatively low, for example, the yield of (i-pr) ₃ Ga·(NEt ₃ ) _0.6 is 27%.

3. Contents of the invention

1. Purpose of the invention: the purpose of the invention is to provide a method for preparing trialkylgallium under the condition of complete anaerobic auxiliary reagent.

2. Technical solution: In order to achieve the above object, the preparation method of the oxygen-free trialkylgallium of the present invention is characterized in that the method is:

Method 1: Place excess organic tertiary amine and gallium-magnesium mixture in a reaction vessel, use Schlenk anaerobic and water-free technology to remove the air in the system and fill it with inert gas, stir and heat (room temperature to 100 ° C), slowly add haloalkane, after the addition, continue to stir for 1-4 hours to make the reaction fully; filter if necessary, and remove the excess organic tertiary amine under reduced pressure from the obtained reaction mixture. Atmospheric or reduced pressure distillation to obtain a mixture of trialkylgallium and amine, or directly decompose the complex to obtain trialkylgallium.

Method Two:

The organic tertiary amine and the gallium-magnesium mixture are placed in a reaction vessel, the air in the system is removed by Schlenk (Schlenk) anaerobic and water-free technology and filled with an inert gas, and a suitable hydrocarbon solvent such as hexane is added, and stirred, Under heating (below the boiling point of the solvent), slowly add haloalkane, after adding, continue to stir for 1-10 hours to make the reaction fully; filter if necessary, and remove the solvent and other volatile compounds under reduced pressure. Substances can be distilled under normal or reduced pressure to obtain a mixture of trialkylgallium and amine complexes. Or directly decompose the complex to obtain trialkylgallium.

3. Beneficial effects

Compared with the prior art, the present invention has the remarkable advantage that under the condition that the organic tertiary amine is used as an oxygen-free auxiliary reagent, and with the assistance of other metals (such as metal magnesium), the direct action of halide methane and metal gallium can be realized , generate trialkylgallium, and the yield is above 30%. The method realizes the anaerobic preparation of the trialkylgallium compound and is easy to operate.

4. Specific implementation

Example 1: In the reaction flask, add triethylamine (excessive), magnesium-gallium mixture, use Schlenk anaerobic and anhydrous technology to remove the air in the system and fill it with nitrogen, under heating (about 40-80 ° C) and stirring , slowly add methyl iodide, after the addition, continue to stir the reaction for 4 hours, distill off excess triethylamine under reduced pressure, and distill under reduced pressure to obtain the complex of trimethylgallium and triethylamine, the yield is 40% based on gallium.

Embodiment 2: In the reaction flask, add N, N-diethylaniline, magnesium gallium mixture, adopt Schlenk anaerobic anhydrous technology to get rid of the air in the system and fill with nitrogen, add toluene as solvent, heat (about 40- 80 ℃), under stirring, add methyl iodide slowly, after adding, continue to stir and react for 6 hours, filter, and the filtrate is under normal pressure or reduced pressure, distill off the solvent and other volatile impurities, trimethylgallium under vacuum The complex with N,N-diethylaniline is decomposed to obtain trimethylgallium, and the yield is 36% based on gallium.

Claims (6)

1, a kind of preparation method of oxygen free trialkyl gallium is characterized in that this preparation method is:

1) trimethylamine, gallium magnesium mixture are placed reaction vessel, the air in the eliminating system also charges into rare gas element;

2) under stirring, heating, add haloalkane, continue to be stirred to sufficient reacting after adding; The temperature of heating is a room temperature to 100 ℃;

3) under reduced pressure remove excessive trimethylamine, normal pressure or underpressure distillation obtain the mixture of trialkyl gallium and amine, or directly carry out title complex and separate and join, and obtain trialkyl gallium;

Described trimethylamine is triethylamine, N, the N-Diethyl Aniline; Described rare gas element is a nitrogen; Haloalkane is a methyl iodide; Trialkyl gallium is a triethyl-gallium.

2, the preparation method of oxygen free trialkyl gallium according to claim 1 is characterized in that 1) in adopt air in the western cold gram anaerobic anhydrous process eliminating system.

3, the preparation method of oxygen free trialkyl gallium according to claim 1 is characterized in that 2) in time of continue stirring be 1-4 hour.

4, a kind of preparation method of oxygen free trialkyl gallium is characterized in that this preparation method is:

1) with trimethylamine as reaction medium, trimethylamine, gallium magnesium mixture are placed reaction vessel, the air in the eliminating system also charges into rare gas element;

2) add varsol, under stirring, heating, add haloalkane, continue to be stirred to sufficient reacting after adding; The temperature of heating is below the boiling point of solvent;

3) under reduced pressure remove and desolvate and volatile matter, normal pressure or underpressure distillation obtain the mixture of trialkyl gallium and amine complex, or directly carry out title complex and separate and join, and obtain trialkyl gallium;

Described trimethylamine is triethylamine, N, the N-Diethyl Aniline; Described rare gas element is a nitrogen; Haloalkane is a methyl iodide; Trialkyl gallium is a triethyl-gallium; Varsol is a toluene.

5, the preparation method of oxygen free trialkyl gallium according to claim 4 is characterized in that 1) in adopt air in the western cold gram anaerobic anhydrous process eliminating system.

6, the preparation method of oxygen free trialkyl gallium according to claim 4 is characterized in that 2) in time of continue stirring be 1-10 hour.