A kind of preparation method of trimethylgallium

Abstract

The invention discloses a preparation method of trimethyl gallium. The preparation method comprises the following steps of: adding a curafume gas into a mixture of metal magnesium and organic ether under the protection of an inert gas at the temperature of 30-100 DEG C and under the normal pressure to generate a methyl-magnesium-bromide solution; continuously stirring at the temperature of 50-100 DEG C for 2-3 hours, and lowering the temperature below 40 DEG C; adding an organic ether solution of absolute gallium trichloride or absolute gallium trichloride into the methyl-magnesium-bromide solution at the temperature of 30-100 DEG C and under the normal pressure, reacting, and continually stirring a reactant for 3-5 hours after reacting; heating a reaction kettle under the normal pressure to 130-190 DEG C, distilling a crude trimethyl gallium product out, and controlling the receiving temperature at 56-62 DEG C; and rectifying the crude product once again under the normal pressure to obtain pure trimethyl gallium, wherein the product collecting temperature is 56 DEG C. The method has the advantages of difficulty in introducing impurities, low cost, high reaction efficiency, high safety, easiness of recovering solvents from produced waste and environment friendliness.

Description

technical field [0001] The invention relates to a preparation method of trimethylgallium. Background technique [0002] Metal-organic compounds such as high-purity trimethylgallium are the most important raw materials for growing optoelectronic materials in the process of metal-organic chemical vapor deposition (MOCVD) and chemical beam epitaxy (CBE), and are widely used in the growth of gallium nitride (GaN ), indium gallium arsenide nitrogen (InGaAsN), indium gallium phosphide (InGaP) and other compound semiconductor thin film materials. Pure trimethylgallium is liquid at room temperature. When used in MOCVD, it is necessary to encapsulate trimethylgallium in a specially designed and manufactured stainless steel cylinder, and then control the temperature of the cylinder to make its vapor pressure reach a certain value, and then through continuous flow The carrier gas brings trimethylgallium in the gas phase under the gas-liquid equilibrium state at the temperature used in...

AI Technical Summary

Problems solved by technology

[0003] There are many preparation methods for trimethylgallium, but there are few methods that can be applied to industrialization. The common method is to use industrial trimethylaluminum and gallium trichloride for transalkylation reaction. The publication number is CN1872862, and the name is trimethylgallium. The patent of gallium-based preparation and purification method discloses this method, which has the following disadvantages: 1) The reaction mechanism is complicated, the reaction conversion efficiency is not high, the yield is 59%, and a large number of by-products are produced; 2) The cost of raw materials is high , as an industrial preparation route, the price of trimethylaluminum is relatively high, so the production cost is extremely high; 3) The raw material is flammable, and there are potential safety hazards. Trimethylaluminum is very sensitive to air and water vapor, spontaneously ignites in air and explodes in water. There are potential safety hazards in filling, transfer, reaction and other processes

4) The reaction process is complicated and impurities are easily introduced

Also have publication number be US4604473, the U.S. patent that name is called Preparation of metal alkyls discloses the method for producing trimethylgallium with methyl iodide, metal magnesium and liquid methyl iodide react in organic ether solution to generate methylmagnesium iodide solution, and then Then react with gallium trichloride to form trimethylgallium, which has the following disadvantages: 1) Since methyl iodide is a liquid, its purity is low, and impurities are easy to introduce; 2) The price of methyl iodide is high, resulting in high production costs; 3) Using Methyl iodide is used as raw material, and the production waste liquid contains inorganic iodide, which is easily oxidized into iodine simple substance, which makes solvent recovery difficult and easy to cause environmental pollution; 4) The reaction conversion efficiency is not high, and the yield is 67%