Device for treating tail gas condensation in crystal growth equipment and crystal growth equipment
By designing a processing device in the crystal growth equipment, using neutralization reaction and increasing the contact time between the exhaust gas and the reaction liquid, the problem of solid blocks generated during exhaust gas cooling is solved, the uniformity and quality of single crystal growth is improved, and the equipment is ensured. stable operation.
Patent Information
- Application Number
- CN202420005198.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-02
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-01-02
AI Technical Summary
In crystal growth equipment, chemical reaction occurs when the exhaust gas is cooled to form solid blocks or powder, resulting in clogging of the filter device, affecting the flow field distribution of the reaction chamber and the growth quality of the single crystal.
A treatment device is designed, including a housing, carrier plate and exhaust pipe, by neutralizing the acidic or alkaline gas before the exhaust gas cools to 350°C, using acidic or alkaline liquids or solids to neutralize the acidic or alkaline gas to avoid solids. The contact time between the exhaust gas and the reaction liquid is increased through the gap between the cover and the exhaust pipe, thereby improving the processing efficiency.
It effectively avoids the reaction of acidic or alkaline gases in the exhaust gas to produce solid powder, prevents clogging of the filter device, improves the uniformity and quality of single crystal growth, and ensures the airflow stability of the reaction chamber and the working pressure of the mechanical pump.
Smart Images
Figure CN222239578U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of semiconductor equipment, in particular to a device for processing tail gas condensation in a crystal growth device and the crystal growth device. Background Art
[0002] Wide bandgap semiconductor materials are widely used in the preparation of high-brightness LEDs, semiconductor lasers and high-power electronic devices. The main considerations in the development and use of various equipment for producing semiconductor epitaxial wafers are the uniformity of single crystal growth and how to reduce parasitic deposition on the quartz cavity wall caused by gas backflow.
[0003] In actual production, during the growth of nitride single crystals, there will be no problem when the reaction source gas undergoes a chemical reaction when entering the reaction chamber and on the tray surface. However, when the reaction ends and enters the exhaust gas end, a chemical reaction will occur to generate solid blocks or solid powder.
[0004] As time goes by, the solid blocks or solid powder at the exhaust end will quickly clog the filter device before the mechanical pump and become difficult to clean. However, once blockage occurs, it will seriously affect the flow field distribution in the entire reaction chamber, and then affect the source concentration distribution above the substrate tray, which will not only reduce the efficiency of nitride single crystals grown by existing equipment, but also seriously affect the quality of the grown single crystals. Utility Model Content
[0005] To this end, the technical problem to be solved by the utility model is to overcome the technical defect in the prior art that the tail gas in the crystal growth equipment undergoes chemical reaction when cooled to generate solids, which blocks the filtering device before the machine pump and affects the quality of the GaN single crystal.
[0006] In order to solve the above technical problems, the utility model provides a device for treating tail gas condensation in a crystal growth device, the treatment device comprising:
[0007] A shell, which is used to contain the reaction liquid, and the shell is provided with an air inlet and an air outlet, and the air inlet is located above the air outlet;
[0008] A carrier plate, which is used to carry the reaction solid, the carrier plate is horizontally arranged in the shell, a plurality of vent holes are opened on the carrier plate, and the carrier plate is located between the air inlet and the air outlet;
[0009] an exhaust pipe, the exhaust pipe being inserted into the air outlet, the upper end of the exhaust pipe being higher than the reaction liquid in the shell;
[0010] The cover body is located inside the shell, and the cover body is sleeved on the exhaust pipe. A gap is provided between the cover body and the exhaust pipe for gas circulation, and the cover body is arranged higher than the reaction liquid.
[0011] Preferably, the reaction liquid is an acidic liquid or an alkaline liquid;
[0012] When it is necessary to neutralize the acidic gas in the tail gas, the reaction liquid is an alkaline liquid;
[0013] When it is necessary to neutralize the alkaline gas in the tail gas, the reaction liquid is an acidic liquid.
[0014] Preferably, the reaction solid is an acidic solid or a basic solid;
[0015] When it is necessary to neutralize the acidic solid in the tail gas, the reaction solid is an alkaline solid;
[0016] When it is necessary to neutralize the alkaline gas in the tail gas, the reaction solid is an acidic solid.
[0017] Preferably, a filter plate is provided in the exhaust pipe to filter solid impurities.
[0018] Preferably, the temperature of the tail gas treated by the treatment device is higher than 350°.
[0019] Preferably, the reaction solid is NaOH and / or KOH.
[0020] Preferably, the inner diameter of the shell gradually decreases from top to bottom, and the air inlet is located at the top of the shell.
[0021] Preferably, it further comprises a handle, wherein the handle is fixed to the carrier plate and the handle is located on the upper side of the carrier plate.
[0022] Preferably, the cover body is cylindrical.
[0023] Preferably, the carrier plate is detachably disposed in the shell.
[0024] The utility model discloses a crystal growing device, comprising the above-mentioned processing device.
[0025] The above technical solution of the utility model has the following advantages compared with the prior art:
[0026] 1. In the utility model, before the tail gas is cooled to 350°C, the acidic gas or alkaline gas in the tail gas is neutralized to remove the acidic gas or alkaline gas, so as to avoid the alkaline gas and the acidic gas in the tail gas to react to produce solid powder and block the filter device, thereby ensuring that the disturbance caused by the blockage of the air flow is prevented, and improving the uniformity and growth quality of the single crystal growth. The utility model can hold both the reaction liquid and the reaction solid, and has a wide range of applications.
[0027] 2. In the present invention, when a reaction liquid is used, the reaction liquid can be used to treat the tail gas. At this time, since the cover is set on the exhaust pipe, the tail gas is treated by the reaction liquid in the shell, and then enters the exhaust pipe through the gap between the cover and the exhaust pipe, and the exhaust pipe discharges the treated tail gas. In the present invention, the setting of the cover can prevent untreated tail gas from directly entering the exhaust pipe, increase the contact time between the tail gas and the reaction liquid, and improve the tail gas treatment efficiency.
[0028] 3. In the utility model, when a reaction solid is used, a carrier plate is used to support the reaction solid. Since the carrier plate is arranged horizontally and the tail gas flows from top to bottom, the reaction solid on the carrier plate reacts with the tail gas, and the treated gas continues to flow downward through the vent holes on the carrier plate. Finally, the treated tail gas is discharged through the exhaust pipe. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In order to make the content of the utility model more clearly understood, the utility model is further described in detail below based on specific embodiments of the utility model in combination with the accompanying drawings.
[0030] Figure 1 It is a structural schematic diagram of the processing device in the utility model;
[0031] Figure 2 is a cross-sectional view of a processing device;
[0032] Figure 3 This is a schematic diagram of the structure of the crystal growth equipment.
[0033] Explanation of the reference numerals in the specification: 10, shell; 11, air inlet; 20, carrier plate; 21, handle; 22, vent; 30, exhaust pipe; 40, cover; 41, filter plate; 50, processing device; 60, gallium boat. DETAILED DESCRIPTION
[0034] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.
[0035] Reference Figure 1-Figure 2 As shown, the utility model discloses a device for processing tail gas condensation in a crystal growth device. The processing device comprises a shell 10 , a carrier plate 20 , an exhaust pipe 30 and a cover body 40 .
[0036] The shell 10 is used to contain the reaction liquid. An air inlet and an air outlet are provided on the shell 10. The air inlet is located on the upper side of the air outlet.
[0037] The carrier plate 20 is used to carry the reaction solid. The carrier plate 20 is horizontally disposed in the housing 10 . A plurality of vent holes 22 are formed on the carrier plate 20 . The carrier plate 20 is located between the air inlet and the air outlet.
[0038] The exhaust pipe 30 is inserted into the air outlet, and the upper end of the exhaust pipe 30 is higher than the reaction liquid in the shell 10 .
[0039] The cover body 40 is located inside the shell 10 , and is sleeved on the exhaust pipe 30 . A gap is provided between the cover body 40 and the exhaust pipe 30 for gas circulation, and the cover body 40 is provided higher than the reaction liquid.
[0040] Furthermore, the lowest point of the cover body 40 needs to be slightly higher than the reaction liquid to prevent the reaction liquid from entering the cover body 40 and then entering the exhaust pipe 30 when the gas pressure introduced into the air inlet is too high, thereby affecting the reaction process.
[0041] In the existing crystal growth equipment, since the exhaust gas contains NH3 and HCl gases, when the gas temperature is less than 350°, the two will react chemically to generate NH4Cl solid blocks or solid powders. This solid powder will block the filter device in the exhaust gas treatment equipment. Once blocked, it will seriously affect the flow field distribution in the entire reaction chamber, and then affect the source concentration distribution above the substrate tray, resulting in reduced efficiency of growing crystals, seriously affecting the quality of GaN single crystals. In the utility model, before the exhaust gas is cooled to 350°C, the acidic gas or alkaline gas in the exhaust gas is neutralized to remove the acidic gas or alkaline gas, so as to avoid the alkaline gas in the exhaust gas and the acidic gas from reacting to produce solid powder and clogging the filter device, thereby ensuring that disturbances due to airflow blockage occur and improving the uniformity and growth quality of single crystal growth. The utility model can hold both reaction liquid and reaction solids, and has a wide range of applications.
[0042] It should be noted that in the present invention, when the reaction liquid is used, the carrier plate 20 can be removed, and the exhaust gas can be treated only with the reaction liquid. Of course, the carrier plate 20 can also be left unremoved, and the multiple vents 22 on the carrier plate 20 can make the airflow of the exhaust gas more uniform. At this time, since the cover body 40 is sleeved on the exhaust pipe 30, the exhaust gas is treated by the reaction liquid in the shell 10, and then enters the exhaust pipe 30 through the gap between the cover body 40 and the exhaust pipe 30, and the exhaust pipe 30 discharges the treated exhaust gas. In the present invention, the setting of the cover body 40 can prevent the untreated exhaust gas from directly entering the exhaust pipe 30, increase the contact time between the exhaust gas and the reaction liquid, and improve the exhaust gas treatment efficiency.
[0043] When reaction solids are used, a carrier plate 20 is used to support the reaction solids. Since the carrier plate 20 is arranged horizontally and the exhaust gas flows from top to bottom, the reaction solids on the carrier plate 20 react with the exhaust gas, and the treated gas continues to flow downward through the vent holes 22 on the carrier plate 20. Finally, the treated exhaust gas is discharged through the exhaust pipe 30.
[0044] To treat the tail gas, either the reaction liquid or the reaction solid can be used. The staff can choose according to the specific work requirements.
[0045] The reaction liquid is an acidic liquid or an alkaline liquid; when the acidic gas in the tail gas needs to be neutralized, the reaction liquid is an alkaline liquid; when the alkaline gas in the tail gas needs to be neutralized, the reaction liquid is an acidic liquid. The staff can choose to use different types of reaction liquids according to their needs.
[0046] For example, for the growth of GaN single crystals, there will be no problem when NH3 and HCl gases as reaction source gases enter the reaction chamber (temperature in this interval is 850°C) and react (reaction temperature in this interval is 1105°C). However, once these gases react and enter the tail gas end, the temperature is continuously reduced as the water cooling flange acts. When the gas temperature is lower than 350°C, NH3 and HCl gases will immediately react chemically to generate NH4Cl solid blocks or solid powders when they are cooled. Before the tail gas temperature is reduced to 350°C, the utility model adds a reaction liquid to the shell 10 of the processing device. For example, the reaction liquid is a concentrated acid solution. The concentrated acid solution will react with NH3 to remove NH3 in the tail gas. In this way, no solid will be generated during the subsequent tail gas cooling process, and the filter device will not be blocked, thereby ensuring the stability of the airflow in the entire reaction chamber and improving the uniformity of crystal growth.
[0047] The reaction solid is an acidic solid or an alkaline solid; when the acidic solid in the tail gas needs to be neutralized, the reaction solid is an alkaline solid; when the alkaline gas in the tail gas needs to be neutralized, the reaction solid is an acidic solid. Similarly, the staff can choose to use different types of reaction solids according to their needs.
[0048] For example, for the growth of GaN single crystals, there will be no problem when NH3 and HCl gases, as reaction source gases, enter the reaction chamber (temperature in this interval is 850°C) and react (reaction temperature in this interval is 1105°C). However, once these gases react and enter the tail gas end, the temperature is continuously reduced as the water cooling flange acts. When the gas temperature is lower than 350°C, NH3 and HCl gases will immediately react chemically to generate NH4Cl solid blocks or solid powders when they are cooled. Before the tail gas temperature is reduced to 350°C, the utility model places a reaction solid on the carrier of the processing device. The reaction solid can be NaOH or KOH, or a combination of NaOH and KOH. The reaction solid reacts with HCl to remove HCl in the tail gas. In this way, no solid will be generated during the subsequent tail gas cooling process, and the filter device will not be blocked, thereby ensuring the stability of the airflow in the entire reaction chamber and improving the uniformity of crystal growth.
[0049] In addition, the carrier plate 20 can be used to carry the reaction solid while the shell 10 can contain the same type of reaction liquid. For GaN single crystal growth, alkaline reactants are used to remove tail gas, which is relatively cheap. Therefore, the carrier plate 20 can be used to carry the alkaline reaction solid while the shell 10 can contain the same type of alkaline reaction liquid. Through multi-layer removal, the tail gas removal effect is better.
[0050] A filter plate 41 is disposed in the exhaust pipe 30 to filter solid impurities. The filter plate 41 may be a plate body having a plurality of holes.
[0051] The temperature of the tail gas treated by the treatment device 50 is higher than 350°. Within this temperature range, the acid and alkali gases in the tail gas can be prevented from reacting. Specifically, the reaction of NH3 and HCl gases can be prevented.
[0052] In the present invention, the inner diameter of the housing 10 gradually decreases from top to bottom, and the air inlet 11 is located at the top of the housing 10. In this way, the air inlet 11 is relatively large, and the exhaust gas enters through the air inlet 11, and the treated exhaust gas is output through the exhaust pipe 30 with a smaller diameter, thereby ensuring a higher exhaust gas treatment efficiency.
[0053] The carrier plate 20 is detachably arranged in the housing 10, so that it is convenient to assemble the carrier plate 20 into the housing 10 and to remove the carrier plate 20 from the housing 10. The utility model also includes a handle 21, which is fixedly arranged with the carrier plate 20 and is located on the upper side of the carrier plate 20. The handle 21 shell is T-shaped, and the carrier plate 20 can be easily extracted through the handle 21, so as to facilitate the replacement of the reaction solid. Since the housing 10 in the utility model is a conical structure, it is convenient to place the carrier plate 20. When the carrier plate 20 is placed in the conical housing 10, it will be stuck in the conical housing 10.
[0054] Furthermore, in order to cover the exhaust pipe 30, since the exhaust pipe 30 is cylindrical, the cover body 40 can also be set to a cylindrical shape. Four screws are set on the top shell of the exhaust pipe 30, and the heights of the four screws are the same. The tops of the screws are higher than the exhaust pipe 30. When the cover body 40 is covered on the exhaust pipe 30, the cover body 40 is pressed on the screws, so that there is a gap between the exhaust pipe 30 and the cover body 40, which facilitates the flow of exhaust gas.
[0055] In another embodiment, the utility model discloses a crystal growth device, comprising the above-mentioned processing device 50. Figure 3 As shown, HCl / N2 / H2 participates in chemical reaction through gallium boat 60 to generate GaCl, and the temperature at gallium boat 60 is 850°C, and then GaCl and NH3 react chemically on the substrate holder to generate GaN single crystal. Because GaCl gas is expensive, the amount of NH3 in the reactor is generally large, in order to improve the utilization rate of gallium. Subsequently, the unreacted HCl gas will be passed to the tail gas end together with NH3 / N2 / H2. When the temperature of these mixed gases is less than 350°C, NH3 and HCl gases will immediately react chemically to generate NH4Cl solid blocks or solid powders when they are cooled. The pressure of the single crystal growth equipment is generally controlled at about 0.5atm by a mechanical pump. In order to ensure the stability of the working pressure of the mechanical pump, a filter device needs to be set in front of the mechanical pump. The NH4Cl solid blocks or solid powders will quickly block these filter devices and make them difficult to clean, which reduces the efficiency of the existing equipment using the HVPE method to grow GaN single crystals, and in severe cases, it will also affect the quality of the grown GaN single crystals. For this purpose, the utility model arranges the above-mentioned processing device 50 on the exhaust gas conveying pipeline, and the carrier plate 20 of the processing device 50 contains NaOH / KOH alkaline solids. When these mixed gases pass through the carrier plate 20, HCl in the mixed gas will react with the NaOH / KOH alkaline solids on the carrier plate 20, and the mixed gas after treatment will no longer contain HCl gas. When the mixed gas is cooled to 350°C through the water-cooling flange, NH3 and HCl gases will not react immediately when cooled to generate NH4Cl solid blocks or solid powder. The entire HVPE method for growing GaN single crystals will no longer require filter barrels, filters and other solid condensate blocks. The processing device 50 saves space and ensures the stability of the working pressure of the mechanical pump, the flow field distribution in the reaction chamber, and the source concentration distribution above the substrate tray, thereby improving the growth efficiency of GaN single crystals using the HVPE method in existing equipment and improving the growth quality of GaN single crystals.
[0056] After testing, it was found that the crystal growth equipment equipped with the processing device 50 of the present invention had smooth gas flow in the reaction chamber and significantly improved the growth uniformity of the grown GaN single crystal.
[0057] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.
Claims
1. A device for treating tail gas condensation in a crystal growth device, characterized in that: include: A shell, which is used to contain the reaction liquid, and the shell is provided with an air inlet and an air outlet, and the air inlet is located above the air outlet; A carrier plate, which is used to carry the reaction solid, the carrier plate is horizontally arranged in the shell, a plurality of vent holes are opened on the carrier plate, and the carrier plate is located between the air inlet and the air outlet; An exhaust pipe, the exhaust pipe being inserted into the air outlet; The cover body is located inside the shell, and the cover body is sleeved on the exhaust pipe. A gap is provided between the cover body and the exhaust pipe for gas circulation, and the cover body is arranged higher than the reaction liquid.
2. The device for treating tail gas condensation in a crystal growth device according to claim 1, characterized in that: The reaction liquid is an acidic liquid or an alkaline liquid; When it is necessary to neutralize the acidic gas in the tail gas, the reaction liquid is an alkaline liquid; When it is necessary to neutralize the alkaline gas in the tail gas, the reaction liquid is an acidic liquid.
3. The device for treating tail gas condensation in a crystal growth device according to claim 1, characterized in that: The reaction solid is an acidic solid or a basic solid; When it is necessary to neutralize the acidic solid in the tail gas, the reaction solid is an alkaline solid; When it is necessary to neutralize the alkaline gas in the tail gas, the reaction solid is an acidic solid.
4. The device for treating tail gas condensation in a crystal growth device according to claim 1, characterized in that: A filter plate is arranged in the exhaust pipe to filter solid impurities.
5. The device for treating tail gas condensation in a crystal growth device according to claim 1, characterized in that: The inner diameter of the shell gradually decreases from top to bottom, and the air inlet is located at the top of the shell.
6. The device for treating tail gas condensation in a crystal growth device according to claim 5, characterized in that: It also includes a handle, which is fixed to the carrier plate and is located on the upper side of the carrier plate.
7. The device for treating tail gas condensation in a crystal growth device according to claim 1, characterized in that: The carrier plate is detachably disposed in the shell.
8. A crystal growth device, characterized in that: A processing device comprising any one of claims 1 to 7.