阅读说明：本技术 尾气洗涤塔及洗涤方法、半导体刻蚀设备 (Tail gas washing tower, washing method and semiconductor etching equipment ) 是由 曹兴龙 于 2020-04-30 设计创作，主要内容包括：本发明提供一种尾气洗涤塔及洗涤方法、半导体刻蚀设备。洗涤塔包括塔体、进气管路、离心泵及补水管路；塔体的底部设置有反应槽；进气管路包括进气端及出气端,进气端与设备的尾气排放管路相连接,出气端与反应槽相连接；离心泵与反应槽及进气管路相连通；补水管路一端与供水源相连接,另一端与进气管路的进气端相连接,用于向进气管路内补水,以使尾气和水混合。本发明的尾气洗涤塔通过优化的结构设计,可以提高特定制程时洗涤塔的处理效率,有助于保护环境、避免真空回灌风险、延长排放管路和洗涤塔的使用寿命。采用本发明的尾气洗涤塔、洗涤方法,以及半导体刻蚀设备,有助于降低生产成本和提高设备产出率。(The invention provides a tail gas washing tower, a washing method and semiconductor etching equipment. The washing tower comprises a tower body, an air inlet pipeline, a centrifugal pump and a water supplementing pipeline; the bottom of the tower body is provided with a reaction tank; the gas inlet pipeline comprises a gas inlet end and a gas outlet end, the gas inlet end is connected with a tail gas discharge pipeline of the equipment, and the gas outlet end is connected with the reaction tank; the centrifugal pump is communicated with the reaction tank and the air inlet pipeline; one end of the water replenishing pipeline is connected with a water supply source, and the other end of the water replenishing pipeline is connected with the air inlet end of the air inlet pipeline and used for replenishing water into the air inlet pipeline so as to mix tail gas and water. The tail gas washing tower disclosed by the invention can improve the treatment efficiency of the washing tower in a specific manufacturing process through an optimized structural design, is beneficial to protecting the environment, avoiding the risk of vacuum recharge and prolonging the service lives of a discharge pipeline and the washing tower. The tail gas washing tower, the washing method and the semiconductor etching equipment are beneficial to reducing the production cost and improving the output capacity of the equipment.)

1. An exhaust gas scrubbing tower, comprising:

the bottom of the tower body is provided with a reaction tank for treating tail gas;

the gas inlet pipeline comprises a gas inlet end and a gas outlet end, the gas inlet end is connected with a tail gas discharge pipeline of equipment, and the gas outlet end is connected with the reaction tank;

the centrifugal pump is communicated with the reaction tank and the air inlet pipeline and is used for conveying tail gas into the reaction tank through the air inlet pipeline;

and one end of the water replenishing pipeline is connected with a water supply source, and the other end of the water replenishing pipeline is connected with the air inlet end of the air inlet pipeline and is used for replenishing water into the air inlet pipeline so as to mix tail gas and water.

2. The tail gas scrubbing tower of claim 1, wherein: and the water replenishing pipeline is provided with a control valve for controlling the water supply amount according to the requirement.

3. The tail gas scrubbing tower of claim 1, wherein: a water-gas mixing pipeline is arranged in the reaction tank, the gas inlet end of the water-gas mixing pipeline is connected with the gas outlet end of the gas inlet pipeline, and a water-gas jet orifice is arranged on the water-gas mixing pipeline; the impeller of the centrifugal pump is positioned in the reaction tank to suck water vapor into the water vapor mixing pipeline, and then the water vapor is sprayed into the reaction tank through the water vapor spraying opening.

4. The tail gas scrubbing tower of claim 1, wherein: the upper part of the reaction tank is provided with a self-overflow port, and the lower part of the reaction tank is provided with a drainage pipeline and a manual valve positioned on the drainage pipeline.

5. The tail gas scrubbing tower of claim 1, wherein: still be provided with a plurality of nozzles in the tower body, be located the upper portion of tower body, a plurality of nozzles are connected with the washing water source for to watering in the tower body.

6. The tail gas scrubbing tower of claim 1, wherein: still be provided with the demister in the tower body, be located the upper portion of tower body is used for the warp the gas that tail gas washing tower discharged removes the bubble and handles.

7. The tail gas scrubbing tower of claim 1, wherein: and a mist catcher is also arranged in the tower body and is positioned at an air outlet of the tail gas washing tower.

8. The tail gas wash tower according to any one of claims 1 to 7, wherein: the tail gas comprises sulfur hexafluoride and oxygen.

9. A semiconductor etching apparatus, characterized in that: the semiconductor etching equipment comprises a metal etching chamber and the tail gas washing tower as claimed in any one of claims 1 to 8, wherein a tail gas discharge pipeline of the metal etching chamber is communicated with an air inlet pipeline of the tail gas washing tower.

10. An off-gas scrubbing method, characterized in that the off-gas scrubbing method is carried out in the off-gas scrubbing tower according to any one of claims 1 to 8.

Technical Field

The invention relates to the field of semiconductor chip manufacturing, in particular to a tail gas washing tower and a washing method for treating tail gas in a semiconductor metal etching process, and semiconductor etching equipment.

Background

The Venturi bubble scrubber is a tail gas treatment device commonly used in semiconductor chip manufacturing plants, and has the greatest advantage that the Venturi bubble scrubber can achieve the obvious effect of treating water-soluble gases such as various acids, alkalis and the like and dust by only using tap water without adding any chemical agent, for example, the Venturi bubble scrubber can treat process tail gas after metal etching.

In the chip manufacturing process, a lot of raw materials containing metal materials are used to manufacture interconnection structures such as plugs, and tungsten is the most commonly used. In a general tungsten process, a large amount of sulfur hexafluoride (SF6) and oxygen (O2) are used as process gases, and residues of the two process gases are likely to react to generate particles of tungsten hexafluoride (WF6) and sulfur dioxide (SO2) which are attached to the surfaces of a discharge pipeline and a treatment tank of a scrubber tower, SO that the exhaust gas discharge efficiency and the treatment efficiency of the scrubber tower are seriously affected. If the tungsten hexafluoride is not completely treated, fluorides such as hydrofluoric acid and the like can be generated, corrosion of pipelines and equipment is caused, harm is caused to the environment, the washing tower pump is overloaded in severe cases, the risk of electricity jump exists, and even tail gas can be caused to flow backwards into etching equipment, so that huge economic loss is caused. In order to ensure the safety of equipment, the existing method generally relies on maintenance personnel to manually clean sulfides and fluorides on the surface of a washing tower regularly, and crystals in a washing tower groove are manually cleaned out, so that the efficiency is low, the health of the maintenance personnel is threatened, and meanwhile, the equipment needs to be shut down in the manual cleaning process, so that the output rate of the equipment is reduced.

Disclosure of Invention

In view of the above disadvantages of the prior art, an object of the present invention is to provide an exhaust gas washing tower, a washing method, and a semiconductor etching apparatus, which are used to solve the problems in the prior art that reaction products of exhaust gas emissions are attached to the surfaces of an exhaust pipeline and a treatment tank of the washing tower, which seriously affect the exhaust gas emission efficiency and the treatment efficiency of the washing tower, and easily cause corrosion of the pipeline and the equipment, and even cause an excessive load on the washing tower, which causes the risk of exhaust gas backflow, and manual cleaning is inefficient, and the cleaning process may harm the health of workers, and the equipment needs to be shut down during the cleaning process, which causes the decrease of the yield of the equipment.

In order to achieve the above objects and other related objects, the present invention provides a tail gas washing tower, comprising a tower body, an air inlet pipeline, a centrifugal pump and a water supply pipeline; the bottom of the tower body is provided with a reaction tank for treating tail gas; the gas inlet pipeline comprises a gas inlet end and a gas outlet end, the gas inlet end is connected with a tail gas discharge pipeline of equipment, and the gas outlet end is connected with the reaction tank; the centrifugal pump is communicated with the reaction tank and the air inlet pipeline and is used for conveying tail gas into the reaction tank through the air inlet pipeline; one end of the water replenishing pipeline is connected with a water supply source, and the other end of the water replenishing pipeline is connected with the air inlet end of the air inlet pipeline and used for replenishing water into the air inlet pipeline so as to mix tail gas and water.

Optionally, a control valve is arranged on the water replenishing pipeline and used for controlling the water supply amount according to the requirement.

Optionally, a water-gas mixing pipeline is arranged in the reaction tank, a gas inlet end of the water-gas mixing pipeline is connected with a gas outlet end of the gas inlet pipeline, and a water-gas injection port is arranged on the water-gas mixing pipeline; the impeller of the centrifugal pump is positioned in the reaction tank to suck water vapor into the water vapor mixing pipeline, and then the water vapor is sprayed into the reaction tank through the water vapor spraying opening.

Optionally, the upper part of the reaction tank is provided with a self-overflow port, and the lower part of the reaction tank is provided with a drainage pipeline and a manual valve positioned on the drainage pipeline.

Optionally, still be provided with a plurality of nozzles in the tower body, be located the upper portion of tower body, a plurality of nozzles are connected with the washing water source for to the watering in the tower body.

Optionally, still be provided with the demister in the tower body, be located the upper portion of tower body is used for removing the bubble to the process gas that tail gas scrubbing tower discharged.

Optionally, a mist catcher is further arranged in the tower body and located at an air outlet of the tail gas washing tower.

Optionally, the tail gas comprises sulphur hexafluoride and oxygen.

The invention also provides semiconductor etching equipment which comprises a metal etching chamber and the tail gas washing tower in any scheme, wherein a tail gas discharge pipeline of the metal etching chamber is communicated with an air inlet pipeline of the tail gas washing tower.

The invention also provides a tail gas washing method, which is carried out according to the tail gas washing tower in any scheme.

As described above, the tail gas washing tower of the invention can improve the treatment efficiency of the washing tower in a specific process by the optimized structural design, and is beneficial to protecting the environment; the risk of vacuum recharge caused by the overweight load of the washing tower pump can be effectively avoided; in addition, the service lives of the discharge pipeline and the washing tower can be prolonged, and the threat to the health of workers in the manual cleaning operation process is avoided. The tail gas washing tower, the washing method and the semiconductor etching equipment are beneficial to reducing the production cost and improving the output capacity of the equipment.

Drawings

Fig. 1 is a schematic structural view of an exhaust gas scrubbing tower according to a first embodiment of the present invention.

Fig. 2 is a schematic diagram illustrating an exemplary connection structure of the water supply pipeline and the air inlet pipeline of the tail gas scrubbing tower according to the present invention.

Fig. 3 is a schematic structural diagram of a semiconductor etching apparatus according to a second embodiment of the present invention.

Description of component reference numerals

11-a reaction tank; 12-an air intake line; 13-a tail gas discharge pipeline; 14-a centrifugal pump; 15-water supplement pipeline; 16-a water supply source; 17-a control valve; 18-a water gas mixing line; 19-Metal etch Chamber

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Please refer to fig. 1 to 3. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, and the form, quantity and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complicated. In order to make the drawings as concise as possible, the same structures in the same drawings are not repeated as much as possible in the present specification.

Example one

As shown in fig. 1, the present invention provides an exhaust gas washing tower, which comprises a tower body, an air inlet pipeline 12, a centrifugal pump 14 and a water replenishing pipeline 15; a reaction tank 11 is arranged at the bottom of the tower body and used for treating tail gas; the gas inlet pipeline 12 comprises a gas inlet end and a gas outlet end, the gas inlet end is connected with a tail gas discharge pipeline 13 of the equipment, and the gas outlet end is connected with the reaction tank 11; the centrifugal pump 14 is communicated with the reaction tank 11 and the air inlet pipeline 12 and is used for conveying tail gas into the reaction tank 11 through the air inlet pipeline 12; one end of the water replenishing pipeline 15 is connected with a water supply source 16, and the other end of the water replenishing pipeline is connected with the air inlet end of the air inlet pipeline 12 and is used for replenishing water into the air inlet pipeline 12 so as to mix tail gas and water. The tail gas washing tower can improve the treatment efficiency of the washing tower in a specific process through the optimized structural design, and is beneficial to protecting the environment; the risk of vacuum recharge caused by the overweight load of the washing tower pump can be effectively avoided; in addition, the service lives of the discharge pipeline and the washing tower can be prolonged, and the threat to the health of workers in the manual cleaning operation process is avoided. The tail gas washing tower is beneficial to reducing the production cost and improving the equipment yield.

As an example, the material of the tower body is preferably a metal material such as stainless steel, and in order to avoid corrosion, an anti-corrosion coating may be formed on the inner surface of the tower body; the top of the tower body can be provided with an exhaust port, and the gas after purification treatment is discharged through the exhaust port.

As an example, the water supply line 15 is provided with a control valve 17 for controlling the water supply amount according to the need, such as the exhaust gas amount to be treated, the exhaust gas composition, etc., and the control valve 17 may be a flow valve to precisely control the water supply amount. And a flow meter may be further provided on the water replenishing pipe 15 between the control valve 17 and the intake pipe 12 to further precisely control the amount of water supply.

For example, the water in the water replenishing pipeline 15 may be tap water or alkaline water, which is determined according to the requirement of the exhaust gas treatment, and is not limited in this embodiment. And in one example, a heater may be disposed on the inlet conduit 12, such as on an outer surface of the inlet conduit 12, to heat the inlet conduit 12 to prevent particles (e.g., particles of tungsten hexafluoride and sulfur dioxide) from adhering to an inner surface of the inlet conduit 12 (the particles may melt when heated), while enhancing the scrubbing effectiveness of the water.

As shown in fig. 2, in an example, the water replenishing pipeline 15 is obliquely connected to the intake pipeline 12, so that water in the water replenishing pipeline 15 naturally flows into the intake pipeline 12 under the action of gravity to mix with the exhaust gas in the intake pipeline 12, thereby avoiding obstruction to normal flow of the exhaust gas, and avoiding water from splashing back into the water replenishing pipeline 15 after colliding with the inner wall of the intake pipeline 12. In the process that water flows into the air inlet pipeline 12 naturally, a part of water flows into the reaction tank 11 along the inner wall of the air inlet pipeline 12, so that the inner wall of the air inlet pipeline 12 can be cleaned well, and crystals are prevented from being deposited on the inner wall of the air inlet pipeline 12. Through the continuous water supplement of the water supplement pipeline 15, the tail gas in the air inlet pipeline 12 is mixed with water, original particle impurities in the tail gas are easier to settle, and meanwhile, the problems that the treatment efficiency of the washing tower is reduced and the corrosion pollution is caused to the air inlet pipeline 12 and the washing tower due to the fact that crystals generated by mutual reaction between residual process gases in the tail gas are attached to the surfaces of the air inlet pipeline 12 and the washing tower can be effectively avoided (namely, in the invention, the tail gas is fully mixed and reacted with the water before entering the washing tower, and in the prior art, the tail gas is mixed with the water after entering the inside of the washing tower). And the process can be automatically carried out under the condition that production equipment is not required to be shut down, the surface of the washing tower is not required to be manually cleaned regularly, the working efficiency can be greatly improved, the labor cost is reduced, and the equipment yield is improved.

As an example, a water-gas mixing pipeline 18 is arranged in the reaction tank 11, a gas inlet end of the water-gas mixing pipeline 18 is connected with a gas outlet end of the gas inlet pipeline 12, and a water-gas injection port is arranged on the water-gas mixing pipeline 18; the impeller of the centrifugal pump 14 is located in the reaction tank 11 to suck water vapor (the exhaust gas is mixed with water in the air inlet pipeline 12 to form gas with liquid, i.e., water vapor) into the water-gas mixing pipeline 18, and then the gas vapor is injected into the reaction tank 11 through the water-vapor injection port. Because the centrifugal pump 14 continuously provides suction, the reverse flow of water vapor/steam back to the exhaust gas discharge pipeline 13 and/or the water supplementing pipeline 15 is not required to be worried about. Of course, the water-gas mixing pipeline 18 can also be regarded as an extension of the air inlet pipeline 12, and it is important that it is located in the reaction tank 11 and generally below the liquid level of the reaction tank 11, so that the water vapor from the air inlet pipeline 12 is sufficiently mixed and reacted with the liquid (mainly water) in the reaction tank 11 again, so as to make the particles carried in the exhaust gas, especially the toxic and harmful particles, such as crystals of disulfide, and the like, and dissolve/settle the toxic gas in the exhaust gas emission into the liquid in the reaction tank 11, thereby achieving the effect of exhaust gas purification.

As an example, the upper part of the reaction tank 11 is provided with a self-overflow port, and the lower part is provided with a drain pipeline and a manual valve positioned on the drain pipeline. The water overflowing from the overflow port of the reaction tank 11 can be used as the supply of the water supply source, so as to realize the recycling of water resources. The drain line and the manual valve on the drain line can be opened to clear the sediment in the reaction tank 11 when necessary. The bottom surface of the reaction tank 11 may be formed into a funnel-like structure with a deep center and a shallow periphery to facilitate the settling of the particles.

As an example, a plurality of nozzles are further arranged in the tower body and located at the upper part of the tower body, and the nozzles are connected with a washing water source and used for sprinkling water into the tower body. The flushing water source and the water supply source of the water replenishing pipeline may be the same water source, such as water overflowing from the overflow port of the reaction tank 11, so as to realize recycling. And as an example, a wave line guide plate can be arranged in the washing tower, so that water flow can flow to the reaction tank 11 along the guide plate, and simultaneously, gas ascending from the reaction tank 11 is fully contacted with the guide plate, wherein the residual particulate impurities are settled through collision with the guide plate.

As an example, a demister is further disposed in the tower body, and is located at an upper portion of the tower body and used for defoaming the gas discharged through the tail gas washing tower.

As an example, a mist catcher is further arranged in the scrubbing tower and is positioned at the air outlet of the scrubbing tower and used for removing moisture in the gas.

In order to make the technical scheme and advantages of the present invention more prominent, the working process of the tail gas scrubbing tower of the present invention is exemplarily described as follows:

tail gas discharged by the equipment enters an air inlet pipeline 12 of the washing tower through a tail gas discharge pipeline 13 of the equipment, at the moment, water is supplemented into the air inlet pipeline 12 through a water supplementing pipeline 15, water flow is fully mixed with the tail gas in the air inlet pipeline 12, so that the reaction time of the water and the tail gas in the air inlet pipeline is prolonged, the reaction of the tail gas and water is ensured to be full, under the action of the suction force of a centrifugal pump 14, a water-gas mixture is sprayed into a reaction tank 11 of the washing tower through a water-gas spray nozzle of a water-gas mixing pipeline 18 at a high speed, the effect of automatically cleaning the reaction tank 11 is achieved, and the phenomenon that residual gas in the tail gas reacts to generate crystals to be attached to the inner walls of the air inlet pipeline 12 and the reaction tank 11 is avoided. The gas still with some impurities (including water vapor) after entering the reaction tank 11 flows to the upper part of the washing tower, in the rising process, the water flow sprayed by the nozzle is subjected to secondary purification, the gas after secondary purification continuously rises and passes through the demister for defoaming treatment, and the clean gas after all purification operations is discharged through the exhaust port at the top of the washing tower after being subjected to the water vapor removal treatment of the mist catcher. The inventor verifies the effect of the tail gas washing tower, after the tail gas washing tower is used, the phenomena of crystal attachment residue and pipeline corrosion in the air inlet pipeline and the tail gas washing tower are basically eliminated, the washing tower needs to be washed once in half a month originally, only simple washing is needed to be carried out in annual inspection, the replacement requirement of parts is obviously reduced, and the production cost can be effectively reduced by adopting the tail gas washing tower.

The tail gas washing tower is particularly suitable for tail gas emission treatment in an etching process, such as sulfur hexafluoride, oxygen and the like discharged in a semiconductor metal etching process. The tail gas washing tower disclosed by the invention is used for treating tail gas containing sulfur hexafluoride and oxygen, SO that the phenomenon that the tungsten hexafluoride (WF6) and sulfur dioxide (SO2) particles generated by the reaction of the two gases in the discharging process are attached to the surfaces of the air inlet pipeline and the treatment tank of the washing tower can be effectively avoided, the corrosion to equipment can be effectively avoided, and the power jump and backflow risks caused by the overweight load of a pump of the washing tower can be avoided. And the whole process does not need equipment to be shut down, does not need manual participation, can effectively reduce the labor cost and improve the equipment output rate.

Example two

As shown in fig. 3, the present invention further provides a semiconductor etching apparatus, which includes a metal etching chamber 19 and the exhaust gas washing tower according to any one of the embodiments, wherein the exhaust gas discharge pipeline 13 of the metal etching chamber 19 is communicated with the air inlet pipeline 12 of the exhaust gas washing tower. For the introduction of the tail gas scrubber, please refer to embodiment one, which is not repeated for brevity. The semiconductor etching equipment provided by the invention is used for carrying out a metal etching process, and can ensure that tail gas is timely and thoroughly discharged, thereby being beneficial to improving the production yield and the equipment output capacity.

The invention also provides a tail gas washing method, which is carried out according to the tail gas washing tower in any one embodiment. Therefore, please refer to the first embodiment for the introduction of the tail gas scrubber, which is not repeated for brevity. By adopting the tail gas washing method, the discharged tail gas is mixed with the water flow in the air inlet pipeline before entering the tail gas washing tower, so that the reaction time of the tail gas and the water is increased, the pollution of the residual gas in the tail gas, which reacts with each other to generate crystals, to the equipment can be effectively avoided, the cleaning efficiency can be effectively improved, and the production cost can be reduced.

In summary, the invention provides an exhaust gas washing tower, a washing method and semiconductor etching equipment. The tail gas washing tower comprises a tower body, an air inlet pipeline, a centrifugal pump and a water supplementing pipeline; the bottom of the tower body is provided with a reaction tank for treating tail gas; the gas inlet pipeline comprises a gas inlet end and a gas outlet end, the gas inlet end is connected with a tail gas discharge pipeline of equipment, and the gas outlet end is connected with the reaction tank; the centrifugal pump is communicated with the reaction tank and the air inlet pipeline and is used for conveying tail gas into the reaction tank through the air inlet pipeline; one end of the water replenishing pipeline is connected with a water supply source, and the other end of the water replenishing pipeline is connected with the air inlet end of the air inlet pipeline and used for replenishing water into the air inlet pipeline so as to mix tail gas and water. The tail gas washing tower can improve the treatment efficiency of the washing tower in a specific process through the optimized structural design, and is beneficial to protecting the environment; the risk of vacuum recharge caused by the overweight load of the washing tower pump can be effectively avoided; in addition, the service lives of the discharge pipeline and the washing tower can be prolonged, and the threat to the health of workers in the manual cleaning operation process is avoided. The tail gas washing tower, the washing method and the semiconductor etching equipment are beneficial to reducing the production cost and improving the output capacity of the equipment. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.