CN111777040A

CN111777040A - Purification production process and production system of high-purity germane

Info

Publication number: CN111777040A
Application number: CN202010760970.7A
Authority: CN
Inventors: 曹小林; 裴友宏; 何西; 程紧
Original assignee: Jiangxi Huate Electronic Chemicals Co ltd
Current assignee: Jiangxi Huate Electronic Chemicals Co ltd
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2020-10-16

Abstract

A purification production process of high-purity germane and a production system thereof are provided, wherein the purification production process comprises the following steps: filling an adsorbent into the adsorbent; preparing alkaline liquid and introducing the alkaline liquid into an alkaline cleaner; replacing the plurality of system vessels and piping with helium gas evacuation and activating the adsorber; pre-freezing the condenser and the cold trap; removing carbon dioxide impurities from the germane crude product; removing water from the germane crude product; the germane crude product enters an absorber to deeply remove impurities; separating germane and hydrogen from the germane crude product in a cold trap; deeply removing impurities in the germane crude product cold trap; collecting to obtain high-purity germane. A purification production system comprising: a germane production system and a germane purification system; the germane purification system comprises: the system comprises an alkaline cleaner, a condenser, a No. 1 adsorber, a No. 2 adsorber and a cold trap; the purification production process of the high-purity germane is simple and easy to operate, can be used for preparing the high-purity 5.5N germane, and overcomes the technical problems of large investment, low efficiency, low purity and the like in the prior art for preparing the high-purity germane.

Description

Purification production process and production system of high-purity germane

Technical Field

The invention relates to the technical field of germane purification, in particular to a purification production process and a purification production system of high-purity germane.

Background

Germane is a gaseous compound of germanium, and is mainly used in the semiconductor, photovoltaic solar and integrated circuit industries. Germane is mainly used for producing high purity germanium and germanium epitaxial wafers for the semiconductor industry, since metallic germanium is a good semiconductor material. The method is mainly used for Metal Organic Chemical Vapor Deposition (MOCVD) process in the electronic industry, various amorphous silicon-germanium alloys are prepared together with silane, and compared with silicon, the amorphous a-SiGe alloy has the advantages of lower process temperature, adjustable forbidden band width, complete compatibility with the existing photovoltaic cell process technology and the like, and is mainly used for manufacturing thin-film solar cells.

In the existing germane purification process, a rectifying tower is partially used, but the investment of the rectifying tower is large, and the safety is difficult to guarantee; the other part uses a freezing method, but the purity of the product can not reach the quality standard of the semiconductor industry.

Disclosure of Invention

The present invention is directed to a process for the purification production of high purity germane, which produces high purity germane through the steps (S1) - (S9).

The invention also provides a purification production system of high-purity germane, which comprises: a germane production system and a germane purification system; the germane purification system comprises: the system comprises a caustic scrubber, a condenser, a 1# absorber, a 2# absorber and a cold trap.

In order to achieve the purpose, the invention adopts the following technical scheme:

a purification production process of high-purity germane comprises the following steps:

step (S1): filling the No. 1 adsorber with an adsorbent, and filling the No. 2 adsorber with an adsorbent; preparing alkaline liquid and introducing the alkaline liquid into an alkaline cleaner;

step (S2): replacing the plurality of system vessels and piping with helium gas evacuations and activating the # 1 adsorber and the # 2 adsorber;

step (S3): pre-freezing the condenser and the cold trap;

step (S4): introducing the germane crude product into an alkaline cleaner to deeply remove carbon dioxide impurities in the germane crude product;

step (S5): introducing the germane crude product obtained in the step (S4) into a condenser, and removing most of water in the germane crude product;

step (S6): sequentially feeding the germane crude product obtained in the step (S5) into a 1# adsorber and a 2# adsorber to deeply remove impurities including moisture, digermane, chlorogermane and epoxy germane;

step (S7): introducing the crude germane product obtained in the step (S6) into a cold trap, condensing the crude germane product in the cold trap, evacuating hydrogen through a tail gas pipe, and separating germane and hydrogen;

step (S8): closing the input end and the output end of the cold trap, using helium gas to evacuate and replace, and deeply removing impurities including hydrogen gas, nitrogen gas, oxygen gas, argon gas and carbon monoxide in the cold trap;

step (S9): collecting to obtain high-purity germane.

Preferably, in the step (S1): the # 1 adsorber was packed with 3A molecular sieve and the # 2 adsorber was packed with 13X molecular sieve.

Preferably, in the step (S1), the alkaline liquid with the pH value of 12-13 is configured to be led into an alkaline cleaner.

Preferably, in the step (S3), the condenser is chilled to-20 to-40 ℃ by introducing cold nitrogen into the jacket of the condenser.

Preferably, in the step (S3), liquid nitrogen is introduced into the jacket of the cold trap to freeze the cold trap to-100 to-165 ℃.

Preferably, in the step (S4), the germane crude product is a germane crude product obtained by using germanium dioxide as a raw material and performing reduction with a reducing agent or electrolysis.

Preferably, in the step (S9), the temperature of the jacket of the cold trap is raised, the temperature of the inside of the cold trap is raised, and high-purity germane is collected by a pressure difference.

Preferably, solid, liquid and gas with the temperature of 0-40 ℃ are introduced into a jacket of the cold trap, so that the temperature inside the cold trap is raised, and high-purity germane is collected through pressure difference.

Preferably, the step (S2) of connecting the germane production system pipeline to the germane purification system, and evacuating and replacing the caustic scrubber and the condenser in the germane purification system with high-purity helium gas until the nitrogen content in the caustic scrubber and the precooler is not more than 0.3 ppm; evacuating and replacing containers such as a 1# adsorber, a cold trap and the like and pipelines in the germane purification system by using high-purity helium, heating the 1# adsorber to 300-350 ℃, and evacuating, replacing and activating by using the high-purity helium until the moisture content of the 1# adsorber and the cold trap is not more than 0.05 ppm; heating the 2# adsorber to 300-350 ℃ and using high-purity helium to evacuate and replace and activate until the moisture content of the 2# adsorber is not more than 0.05 ppm.

A purification production system for high purity germane comprising: a germane production system and a germane purification system; the germane purification system comprises: the system comprises an alkaline cleaner, a condenser, a No. 1 adsorber, a No. 2 adsorber and a cold trap;

the germane production system is used for preparing and/or outputting a germane crude product, and the output end of the germane production system is communicated with the input end of the alkaline cleaner;

the alkaline cleaner is filled with alkaline liquid and is used for contacting a germane crude product; the output end of the alkaline cleaner is communicated with the input end of the condenser;

the output end of the condenser is communicated with the input end of the 1# adsorber;

the No. 1 adsorber is filled with a 3A molecular sieve, and the output end of the No. 1 adsorber is communicated with the input end of the No. 2 adsorber;

and the 2# adsorber is filled with a 13X molecular sieve, and the output end of the 2# adsorber is communicated with the input end of the cold trap.

The invention has the beneficial effects that:

the purification production process of the high-purity germane is simple and easy to operate, and can be used for preparing the high-purity 5.5N germane; meanwhile, the specific system is simple, the process is simple, the industrial production can be easily realized, and the technical problems of large investment, low efficiency, low purity and the like in the prior art for preparing high-purity germane are solved.

Drawings

Fig. 1 is a schematic diagram of a production system for high purity germane purification.

Wherein:

germane production system 1, alkaline scrubber 2,

condenser

3, 1#

adsorber

4, 2# adsorber 5, cold trap 6.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

the adsorbent may be replaced by a known adsorbent which adsorbs impurities including moisture, digermane, chlorogermane and germane epoxide; the adsorbent can be used, such as activated carbon, molecular sieve, silica gel and the like, and the physical property and the chemical property of the molecular sieve are different from the adsorption capacity of the molecular sieve on impurity gas; and when the No. 1 adsorber is filled with the 3A molecular sieve and the No. 2 adsorber is filled with the 13X molecular sieve, the purity of the germane can be improved from 5N to 5.5N.

after the 1# absorber and the 2# absorber are activated, the adsorption capacity of the adsorbent in the absorber is improved, and the number and the size of pores can meet the requirement of adsorbing impurities including moisture, digermane, chlorogermane and epoxy germane; especially, when the No. 1 adsorber is filled with 3A molecular sieve and the No. 2 adsorber is filled with 13X molecular sieve, the germane purification system has the best purification capacity, and the purity of germane can reach 5.5N.

Step (S3): pre-freezing the condenser and the cold trap; the condenser and the cold trap are pre-frozen, impurity removal capacity at a specified temperature is achieved before the germane crude product enters the condenser and the cold trap, impurities including moisture, digermane, chlorogermane and epoxy germane can be removed, and impurity removal efficiency is improved.

and removing acidic carbon dioxide in the germane crude product by using alkaline liquid so as to completely remove carbon dioxide impurities in the germane crude product.

Step (S5): introducing the germane crude product obtained in the step (S4) into a condenser, and removing most of water in the germane crude product; when the temperature of water is lower than 0 ℃, the water in the crude germane product is frozen, and the water in the crude germane product is in a solid state and is separated from the crude germane product.

step (S7): introducing the crude germane product obtained in the step (S6) into a cold trap, condensing the crude germane product in the cold trap, evacuating hydrogen through a tail gas pipe, and separating germane and hydrogen; the germane is frozen and liquefied in the cold trap, the hydrogen can not be gas at the temperature of-100 to-165 ℃, the germane and the hydrogen are separated in the state, the hydrogen can be output through the tail gas pipe, and the crude germane is retained in the cold trap.

Step (S8): after the reaction process for producing the crude germane product is finished or the crude germane product is completely introduced, closing the input end and the output end of the cold trap, vacuumizing and replacing the cold trap with helium, and deeply removing impurities including hydrogen, nitrogen, oxygen, argon and carbon monoxide in the cold trap;

step (S9): collecting to obtain high-purity germane.

Preferably, in the step (S1), the alkaline liquid with the pH value of 12-13 is configured to be led into an alkaline cleaner. The alkaline liquid comprises: at least one of sodium hydroxide and potassium hydroxide.

Preferably, in the step (S3), liquid nitrogen is introduced into the jacket of the cold trap to freeze the cold trap to-100 to-165 ℃. The jacket refers to an outer sleeve which is arranged outside the wall (or pipe wall) of the container, so that the wall surface of the container is cooled or heated by cold nitrogen or liquid nitrogen, and the temperature of the inside of the container is controlled by the jacket.

After the temperature of the jacket of the cold trap rises, because the temperature in the cold trap is lower, after the temperature in the cold trap rises, a temperature difference is formed between the inside of the cold trap and the jacket, and then a pressure difference is formed, and germane can be discharged from the inside of the cold trap. The normal temperature fluid is as follows: 25 degrees of water, 23 degrees of nitrogen, 20 degrees of air, etc.

Example A:

step (S1): filling 30Kg of 3A molecular sieve in the 1# adsorber, and filling 30Kg of 13X molecular sieve in the 2# adsorber; preparing sodium hydroxide with the pH value of 13 and the capacity of 100L, and introducing the sodium hydroxide into an alkaline cleaner;

step (S2): heating the 1# adsorber to 350 ℃, preserving the heat for 1 hour, evacuating and replacing containers such as the 1# adsorber, a cold trap and the like and pipelines in a germane purification system for 5 times by using high-purity 5N helium gas, and detecting the moisture content of the 1# adsorber and the cold trap to be 0.03 ppm; heating the 2# adsorber to 350 ℃, preserving the heat for 1 hour, then using high-purity 5N helium gas to evacuate, replace and activate for 5 times, and detecting that the moisture content of the 2# adsorber is 0.03 ppm;

step (S3): introducing cold nitrogen into the jacket of the condenser, and freezing the condenser to-35 ℃; introducing liquid nitrogen into a jacket of the cold trap to freeze the temperature of the cold trap to-150 ℃, and pre-freezing the condenser and the cold trap;

step (S4): starting a spraying circulating pump of the alkali scrubber, and introducing a germane crude product reacted by the germane production system into the alkali scrubber to deeply remove carbon dioxide impurities in the germane crude product;

step (S5): introducing the germane crude product into a condenser, and removing most of water in the germane crude product at the temperature of-35 ℃;

step (S6): the germane crude product sequentially enters a No. 1 adsorber and a No. 2 adsorber, and the 3A molecular sieve and the 13X molecular sieve deeply adsorb impurities such as moisture, digermane, chlorogermane, epoxy germane and the like;

step (S7): introducing the crude germane product into a cold trap, condensing the crude germane product in the cold trap at the temperature of-150 ℃, safely exhausting uncondensed hydrogen through a tail gas pipe, and separating germane and hydrogen;

step (S8): after the reaction process for producing the crude germane product is finished, predicting that 2.05KG germane can be collected, closing the input end and the output end of a cold trap, vacuumizing and replacing by using high-purity 5N helium, and deeply removing impurities such as hydrogen, nitrogen, oxygen, argon, carbon monoxide and the like in the cold trap;

step (S9): and introducing normal-temperature nitrogen into a cold trap jacket, wherein the cold trap can be gradually heated, germane is gasified and pressurized, and qualified empty bottles are connected to a filling exhaust. And opening a bottle valve to start filling when the pressure of the cold trap reaches micro positive pressure, collecting germane into the bottle through pressure difference, and completing filling when the pressure reaches 0.8-1.2MPA to obtain the high-purity germane.

Comparative example a:

the comparison with example A is carried out by taking a foreign high-purity germane index as a comparative example A1 and taking a GB/T31987-.

TABLE 1 comparison of example A with comparative example A1

Description of the drawings:

from example a and comparative example a1, example a is a purification production process herein that further enables collection of 5.5N from crude germane, enabling low cost removal of impurities from crude germane to obtain high purity 5.5N germane. Comparative example a1 is a standard for foreign high purity germane, which is only 5N grade; the germane in the scheme can reach 5.5N, particularly for digermane, chlorogermane and epoxy germane, the purified germane produced by the scheme has low impurity content which is far lower than foreign standards. Meanwhile, as can be seen from the example A and the comparative example A2, the comparative example A2 is the domestic pure germane standard, the purified germane produced by the scheme meets the domestic standard, and the actual content of various impurities is far lower than the range defined by the domestic standard and is 5.5N germane.

Example B:

step (S1): filling 30Kg of adsorbent in the 1# adsorber and 30Kg of adsorbent in the 2# adsorber; preparing sodium hydroxide with the pH value of 13 and the capacity of 100L, and introducing the sodium hydroxide into an alkaline cleaner; the adsorbent is selected from the adsorbent types of examples B1-B16 shown in Table 2;

step (S6): the germane crude product sequentially enters a No. 1 adsorber and a No. 2 adsorber, and an adsorbent adsorbs impurities;

step (S8): after the reaction process for producing the germane crude product is finished, closing the input end and the output end of the cold trap, evacuating and replacing by using high-purity 5N helium, and deeply removing impurities such as hydrogen, nitrogen, oxygen, argon, carbon monoxide and the like in the cold trap;

step (S9): and introducing normal-temperature nitrogen into a cold trap jacket, wherein the cold trap can be gradually heated, germane is gasified and pressurized, and qualified empty bottles are connected to a filling exhaust.

And opening a bottle valve to start filling when the pressure of the cold trap reaches micro positive pressure, collecting germane into the bottle through pressure difference, and completing filling when the pressure reaches 0.8-1.2MPA to obtain germane with different purities.

TABLE 2 adsorbent types for example B

Description of the drawings:

from example B1 to example B2 to B16, examples B1 to B16 were conducted on molecular sieves filled with both the adsorber # 1 and the adsorber # 2, respectively; the results show that the molecular sieves used in examples B2-B16, which were tested on 3A, 4A, 5A and 13X molecular sieves, could purify germane to some extent and achieve a purity of 5N grade; however, when the 3A molecular sieve is arranged in the 1# adsorber and the 13X molecular sieve is arranged in the 2# adsorber, the purification production process has better purity than that of the embodiment B2-B16, can deeply remove moisture, digermane, chlorogermane, epoxy germane and other impurities, has higher impurity removal rate than that of the embodiment B2-B16, and shows that the factors of the positions, the pore diameters, the high-temperature activation results and the like of the 3A molecular sieve and the 13X molecular sieve can further optimize the purification result of the scheme so as to further optimize the germane produced by the purification production process, and the germane of the embodiment B1 can reach 5.5N level and the purity can reach 99.9995%.

Example C

Example C1:

step (S1): filling 40Kg of 3A molecular sieve in the 1# adsorber, and filling 35Kg of 13X molecular sieve in the 2# adsorber; preparing sodium hydroxide with the pH value of 12 and the capacity of 50L, and introducing the sodium hydroxide into an alkaline cleaner;

step (S2): heating the 1# absorber to 300 ℃, preserving heat for 1.5 hours, evacuating and replacing containers such as the 1# absorber, a cold trap and the like and pipelines in a germane purification system for 4 times by using high-purity 5N helium gas, and detecting that the moisture content of the 1# absorber and the cold trap is 0.02 ppm; heating the 2# adsorber to 300 ℃, preserving heat for 1 hour, then using high-purity 5N helium gas to evacuate, replace and activate for 5 times, and detecting that the moisture content of the 2# adsorber is 0.02 ppm;

step (S3): introducing cold nitrogen into the jacket of the condenser, and freezing the condenser to-20 ℃; introducing liquid nitrogen into a jacket of the cold trap to freeze the temperature of the cold trap to-100 ℃, and pre-freezing the condenser and the cold trap;

step (S5): introducing the germane crude product into a condenser, and removing most of water in the germane crude product at the temperature of-20 ℃;

step (S7): introducing the crude germane product into a cold trap, condensing the crude germane product in the cold trap at the temperature of-100 ℃, safely exhausting uncondensed hydrogen through a tail gas pipe, and separating germane and hydrogen;

step (S8): after the reaction process for producing the germane crude product is finished, closing the input end and the output end of the cold trap, vacuumizing and replacing by using high-purity 5N helium, and deeply removing impurities in the cold trap;

step (S9): and introducing normal-temperature nitrogen into a cold trap jacket, wherein the cold trap can be gradually heated, germane is gasified and pressurized, and qualified empty bottles are connected to a filling exhaust. And opening a bottle valve to start filling when the pressure of the cold trap reaches micro positive pressure, collecting germane into the bottle through pressure difference, and completing filling when the pressure reaches 0.8-1.2MPA to obtain germane with different purities.

Example C2:

step (S1): filling 35Kg of 3A molecular sieve in the 1# adsorber, and filling 35Kg of 13X molecular sieve in the 2# adsorber; preparing sodium hydroxide with the pH value of 13 and the capacity of 50L, and introducing the sodium hydroxide into an alkaline cleaner;

step (S2): heating the 1# absorber to 250 ℃, preserving heat for 1.5 hours, evacuating and replacing containers such as the 1# absorber, a cold trap and the like and pipelines in a germane purification system for 4 times by using high-purity 5N helium gas, and detecting that the moisture content of the 1# absorber and the cold trap is 0.02 ppm; heating the 2# adsorber to 250 ℃, preserving heat for 1 hour, then using high-purity 5N helium gas to evacuate, replace and activate for 5 times, and detecting that the moisture content of the 2# adsorber is 0.02 ppm;

step (S3): introducing cold nitrogen into the jacket of the condenser, and freezing the condenser to-40 ℃; introducing liquid nitrogen into a jacket of the cold trap to freeze the temperature of the cold trap to-165 ℃ and pre-freezing the condenser and the cold trap;

step (S5): introducing the germane crude product into a condenser, and removing most of water in the germane crude product at the temperature of-40 ℃;

step (S7): introducing the crude germane product into a cold trap, condensing the crude germane product in the cold trap at the temperature of-165 ℃, safely exhausting uncondensed hydrogen through a tail gas pipe, and separating germane and hydrogen;

Table 3 impurity level testing of example C

	Example C1	Example C2
			Total impurity content (ppm)	≤5	≤10

The technical principle of the present invention is described above in connection with specific embodiments. The description is made for the purpose of illustrating the principles of the invention and should not be construed in any way as limiting the scope of the invention. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present invention without inventive effort, which would fall within the scope of the present invention.

Claims

1. The purification production process of high-purity germane is characterized by comprising the following steps of:

step (S3): pre-freezing the condenser and the cold trap;

step (S9): collecting to obtain high-purity germane.

2. The process for the purification production of high purity germane according to claim 1, wherein in the step (S1): the # 1 adsorber was packed with 3A molecular sieve and the # 2 adsorber was packed with 13X molecular sieve.

3. The process for purifying and producing high purity germane according to claim 1, wherein in the step (S1), the alkaline liquid with pH value of 12-13 is configured to be led into an alkaline cleaner.

4. The process of claim 1, wherein in the step (S3), the condenser is cooled to a temperature of-20 to-40 ℃ by introducing cold nitrogen into the jacket of the condenser.

5. The process for the purification production of high purity germane according to claim 1, wherein in the step (S3), liquid nitrogen is introduced into the jacket of the cold trap to freeze the cold trap temperature to-100 to-165 ℃.

6. The process of claim 1, wherein in step (S4), the crude germane is obtained by using germanium dioxide as a raw material and reducing the germanium dioxide with a reducing agent or electrolysis.

7. The process of claim 1, wherein in the step (S9), the temperature of the jacket of the cold trap is raised, the temperature of the inside of the cold trap is raised, and the high purity germane is collected by the pressure difference.

8. The process of claim 1, wherein the temperature of the inside of the cold trap is raised by introducing solid, liquid and gas at 0-40 ℃ into the jacket of the cold trap, and the high purity germane is collected by pressure difference.

9. The purification process of claim 1 to 8, wherein the step (S2) of connecting the pipeline of the germane production system to the germane purification system, and evacuating and replacing the caustic scrubber and the condenser in the germane purification system with high purity helium gas until the nitrogen content in the caustic scrubber and the precooler is not more than 0.3 ppm; evacuating and replacing containers such as a 1# adsorber, a cold trap and the like and pipelines in the germane purification system by using high-purity helium, heating the 1# adsorber to 300-350 ℃, and evacuating, replacing and activating by using the high-purity helium until the moisture content of the 1# adsorber and the cold trap is not more than 0.05 ppm; heating the 2# adsorber to 300-350 ℃ and using high-purity helium to evacuate and replace and activate until the moisture content of the 2# adsorber is not more than 0.05 ppm.

10. A purification production system of high-purity germane, which is characterized by comprising: a germane production system and a germane purification system; the germane purification system comprises: the system comprises an alkaline cleaner, a condenser, a No. 1 adsorber, a No. 2 adsorber and a cold trap;