阅读说明：本技术 一种砷烷的合成提纯方法 (Synthetic purification method of arsine ) 是由 陈国富 龚施健 于 2019-09-25 设计创作，主要内容包括：本发明提供一种砷烷的合成提纯方法,使用锌粉与砷粉制备砷化锌,然后使用砷化锌粉末与稀硫酸发生反应,然后制得粗制砷烷气体,通过将粗制砷烷气体通过通入第一吸附装置,吸附装置中设有碱性多孔吸附剂,除去粗制砷烷气体中的酸性物质,再通入第二吸附装置,所述第二吸附装置中设有分子筛,除去砷烷气体中的高沸点杂质,最后使用液氮冷肼捕集砷烷气体,使砷烷气体冷凝为液态砷烷,使用真空泵抽去不凝气体,然后取下冷肼外的液氮罐,使砷烷挥发,得到纯净的砷烷气体；纯净的砷烷气体通入预先处理过的洁净钢瓶中进行保存,得到高纯度的砷烷气体成品。本发明提供的合成及提纯方法制备的砷烷成品,纯度可达6N,产品的杂质含量小于0.1ppm。(The invention provides a method for synthesizing and purifying arsine, which comprises the steps of preparing zinc arsenide by using zinc powder and arsenic powder, reacting the zinc arsenide powder with dilute sulfuric acid to prepare rough arsine gas, introducing the rough arsine gas into a first adsorption device, removing acid substances in the rough arsine gas by using an alkaline porous adsorbent in the adsorption device, introducing the rough arsine gas into a second adsorption device, wherein a molecular sieve is arranged in the second adsorption device to remove high-boiling-point impurities in the arsine gas, finally trapping the arsine gas by using liquid nitrogen cold hydrazine to condense the arsine gas into liquid arsine, removing non-condensable gas by using a vacuum pump, taking down a liquid nitrogen tank outside the cold hydrazine to volatilize the arsine, and obtaining pure arsine gas; and introducing the pure arsine gas into a clean steel cylinder which is pretreated for storage to obtain a high-purity arsine gas finished product. The arsine finished product prepared by the synthesis and purification method provided by the invention has the purity of 6N and the impurity content of the product is less than 0.1 ppm.)

1. A synthetic purification method of arsine is characterized in that: the synthetic purification method of arsine comprises the following specific steps:

the method comprises the following steps: weighing zinc powder and arsenic powder, mixing the arsenic powder and the zinc powder according to the mass ratio of 3:4, placing the powder in a quartz vessel after mixing is finished, placing the quartz vessel in a stainless steel reaction tank, vacuumizing, filling high-purity inert gas to the normal pressure, maintaining the pressure at 0.13-0.14 MPa, and heating for 3-4 hours to prepare zinc arsenide for later use;

step two: putting the zinc arsenide powder collected in the step one into a reactor, adding dilute sulfuric acid with the mass concentration of 10-50% while stirring, and reacting to generate crude arsine gas;

step three: introducing the crude arsine gas obtained in the step two into a first adsorption device, wherein an alkaline porous adsorbent is arranged in the adsorption device, so as to obtain an arsine gas A;

step four: introducing the arsine gas A in the third step into a second adsorption device, wherein a molecular sieve is arranged in the second adsorption device, so as to obtain an arsine gas B;

step five: trapping arsine gas B in the fourth step by using liquid nitrogen cold hydrazine, condensing the arsine gas B into liquid arsine, pumping out non-condensable gas by using a vacuum pump, and then taking down a liquid nitrogen tank outside the cold hydrazine to volatilize the arsine to obtain pure arsine gas;

step six: and (5) introducing the pure arsine gas obtained in the step five into a clean steel cylinder which is pretreated in advance for storage, so as to obtain a finished product.

2. The method of claim 1, wherein the synthetic purification of arsine comprises: the high-purity inert gas in the first step can be one of high-purity helium, neon, argon or nitrogen.

3. The method of claim 1, wherein the synthetic purification of arsine comprises: the heating temperature in the first step is 600-620 ℃.

4. The method of claim 1, wherein the synthetic purification of arsine comprises: and in the third step, the alkaline porous adsorbent is a porous adsorbent formed by mixing calcium oxide and sodium oxide in a mass ratio of 96: 4.

5. The method of claim 1, wherein the synthetic purification of arsine comprises: and the molecular sieve in the fourth step is an active alumina silica gel molecular sieve.

6. The method of claim 1, wherein the synthetic purification of arsine comprises: the condensation temperature in the fifth step is-200 to-100 ℃.

7. The method of claim 1, wherein the synthetic purification of arsine comprises: and continuously introducing nitrogen into the reactor in the second step.

8. The method of claim 1, wherein the synthetic purification of arsine comprises: the specification of the molecular sieve in the fourth step is 3A, 4A, 5A or 13A.

Technical Field

The invention relates to the technical field of arsine synthesis, in particular to a method for synthesizing and purifying arsine.

Background

Electronic gases are indispensable raw materials for the industrial production of very large scale integrated circuits, flat panel display devices, compound semiconductor devices, solar cells, optical fibers and the like, and are widely applied to the processes of thin films, etching, doping, vapor deposition, diffusion and the like, for example, in the wafer manufacturing process of very large scale integrated circuit factories with advanced process technologies, all process steps exceed 450, and about 50 different types of electronic gases are used. Arsine is one of the five elements of great importance in electronic gases, an important electronic specialty gas, and is used mainly in the semiconductor industry for N-type doping of epitaxial silicon, N-type diffusion in silicon, ion implantation, growth of gallium arsenide and gallium arsenide phosphide, and the like. Furthermore, arsine has very important applications in optoelectronics, solar cells and micro-blogging devices.

Arsine cannot be synthesized simply by simple substances, but arsine can be obtained in the presence of a catalyst or under plasma irradiation, and some metal arsenides are generally used for preparing arsine by reacting with water or acid, wherein the reaction is rapid and complete, hydrogen is completely absent in the product, but the yield of arsine is generally lower than 90%.

Currently, the concentration of arsine prepared by the international advanced level is 6N, while one of the special gases in China, the purity of arsine can only produce standard special gas with the concentration of 3-4N due to technical reasons, and in many important fields, such as: the 6N standard gas urgently needed in the aspects of national war preparedness weapon research, manufacturing of electronic components of a control system on a Shenzhou five carrier rocket, manufacturing of solar cells used on a satellite and the like is imported, only developed countries such as America, Russia and the like can produce the gas in the world at present, and the gas imported in China is usually hindered due to international situation tension and change, so the development of the related fields is directly restrained by the localization problem of continuous high-purity gas materials in China.

At present, the method for purifying arsine is also published in China and mainly adopted. The gallium indium alloy liquid deeply adsorbs dehydration and oxygen to obtain electronic grade arsine, however, the adsorption mode is not reproducible, and heavy metals are difficult to obtain, so that the cost of the whole system is high, and the popularization is limited.

Disclosure of Invention

The invention aims to provide a method for synthesizing and purifying arsine, which has the advantages of higher purity, quicker reaction and less impurities.

In order to solve the technical problems, the invention adopts the technical scheme that: a synthetic purification method of arsine comprises the following steps:

the method comprises the following steps: weighing zinc powder and arsenic powder, mixing the arsenic powder and the zinc powder according to the mass ratio of 3:4, placing the powder in a quartz vessel after mixing is finished, placing the quartz vessel in a stainless steel reaction tank, vacuumizing, filling high-purity inert gas to the normal pressure, maintaining the pressure at 0.13-0.14 MPa, and heating for 3-4 hours to prepare zinc arsenide for later use;

step two: putting the zinc arsenide powder collected in the step one into a reactor, adding dilute sulfuric acid with the mass concentration of 10-50% while stirring, and reacting to generate crude arsine gas;

step three: introducing the crude arsine gas obtained in the step two into a first adsorption device, wherein an alkaline porous adsorbent is arranged in the adsorption device, so as to obtain an arsine gas A;

step four: introducing the arsine gas A in the third step into a second adsorption device, wherein a molecular sieve is arranged in the second adsorption device, so as to obtain an arsine gas B;

step five: trapping arsine gas B in the fourth step by using liquid nitrogen cold hydrazine, condensing the arsine gas B into liquid arsine, pumping out non-condensable gas by using a vacuum pump, and then taking down a liquid nitrogen tank outside the cold hydrazine to volatilize the arsine to obtain pure arsine gas;

step six: and (5) introducing the pure arsine gas obtained in the step five into a clean steel cylinder which is pretreated in advance for storage, so as to obtain a finished product.

Further, the high purity inert gas in the first step may be one of high purity helium, neon, argon or nitrogen.

Further, the heating temperature in the first step is 600-620 ℃.

Further, the alkaline porous adsorbent in the third step is a porous adsorbent formed by mixing calcium oxide and sodium oxide in a mass ratio of 96: 4.

Further, the molecular sieve in the fourth step is an activated alumina silica gel molecular sieve.

Further, the condensation temperature in the fifth step is-200 to-100 ℃.

Further, nitrogen is continuously introduced into the reactor in the second step.

Further, the size of the molecular sieve in the fourth step is 3A, 4A, 5A or 13A.

Compared with the prior art, the invention has the advantages and positive effects that:

1. the invention can effectively remove water vapor, acidic substances, sulfides and the like in the arsine gas by arranging the alkaline adsorbent, the calcium oxide and the sodium oxide have low price and are convenient to purchase, and the calcium oxide and the sodium oxide after impurity removal can be recycled by treatment, thereby greatly improving the overall performance of the whole device and better meeting the requirements of users.

2. According to the synthetic purification method of arsine, the active silica gel molecular sieve is arranged to remove impurities such as residual water vapor and carbon dioxide in arsine gas, and is composed of at least one active alumina silica gel adsorption unit in series, so that the molecular sieve can be repeatedly used and regenerated, has a long service life and is more suitable for the needs of users.

3. According to the invention, by adopting the method of condensing and vacuumizing liquid nitrogen, small molecular gas impurities such as oxygen and the like in the arsine gas are directly removed, so that the content of harmful impurities in the arsine gas is less than 0.1ppm, the purity of the arsine gas can reach 6N, and the requirements of users can be better met.

Detailed Description

For a better understanding of the present invention, the present invention is further described below in conjunction with specific embodiments.