A method and device for collecting particles in semiconductor process using plasma

Abstract

The present invention discloses a method and device for collecting particulate matter in a semiconductor process using plasma. The method is as follows: 1) a horizontal exhaust channel is established between a vacuum chamber and a vacuum pump in a semiconductor manufacturing process, including a condensation module and a T-shaped pipe arranged in sequence; a plasma generation module and a flow guide module are arranged in the horizontal section of the T-shaped pipe, and a dust collection module is arranged at the lower end outlet of the vertical section; 2) the condensation module cools the residual gas discharged from the vacuum chamber to promote the condensation of substances in the exhaust gas into particles; 3) the plasma generation module discharges to generate plasma, and a plasma region is formed in the horizontal section of the T-shaped pipe, which is used to charge the particles in the exhaust gas flowing through to form charged particles; 4) the flow guide module generates an electric field for repelling charged particles, and guides the vertical section of the T-shaped pipe into the dust collection module, and the residual gas after filtering out the particulate matter is output through the horizontal section outlet. The present invention has the advantages of high collection efficiency and low cost.

Description

Technical Field

[0001] The invention relates to a method for collecting residual gas particles in semiconductor manufacturing, belonging to the technical field of particle removal in semiconductor manufacturing processes. Background Art

[0002] Many micro-nano particles are inevitably formed in the semiconductor thin film deposition and photolithography process. The appearance of these particles not only reduces the yield of the wafer, but also pollutes the vacuum chamber and exhaust system. Therefore, removing particle pollutants is a key link in the semiconductor manufacturing process. Particles come from the factory processing and production environment on the one hand, and solid particles of various sizes generated by complex gas phase reactions in the wafer taping process on the other hand. Among them, particles generated in the wafer taping process are the main source. According to statistics, for the production of 4M DRAM with a design line width of 1mm, 50% of the polluted particles are generated by the factory processing and production environment, and the remaining 50% of the particles are generated by process equipment. In the production of 16M DRAM with a line width of 0.5mm, the particles generated by process equipment increased to 60%; in the production of 64M DRAM with a line width of 0.35mm, the particles generated by process equipment increased to 75%; and in the production of 256M DRAM with a line width of 0.25mm, the particles generated by process equipment will be as high as 90%, becoming the main source of pollution.

[0003] At present, vacuum systems in the semiconductor manufacturing field are Figure 1 As shown in the figure, the vacuum pump is connected to the vacuum chamber through the front vacuum pipe and maintains the vacuum environment in the chamber; the vacuum pump exhaust is connected to the exhaust gas treatment equipment through the exhaust pipe. Since particulate matter is mainly formed in the vacuum chamber, and the vacuum chamber is connected to the exhaust system, the particulate matter will inevitably enter the exhaust system with the residual gas after the gas phase reaction and pollute the exhaust system. On the one hand, the particulate matter will be adsorbed on the wall of the pipe when passing through the exhaust pipe, and it is difficult to fall off, forming permanent pollution. On the other hand, the particulate matter will enter the environment through the exhaust system and pollute the environment. Since the vacuum system works continuously around the clock to maintain the vacuum degree in the vacuum chamber, the particulate matter will continue to accumulate in the exhaust pipe. If it is shut down for maintenance, it will affect the continuous operation of the semiconductor manufacturing process and increase the system cost. Therefore, removing particulate matter in the exhaust system and collecting particulate matter is a key technical issue in the current semiconductor manufacturing field.

[0004] One of the traditional solutions is to add a filtering device, such as a screen, before the dry pump that maintains the vacuum system, and filter the particles by controlling the pore size of the screen, such as Figure 2 The disadvantage of this method is that the screen will affect the pumping speed of the vacuum pump and there is a risk of clogging, so it is rarely used.

[0005] The patent with publication number CN117357991A discloses a semiconductor production waste gas treatment process, which includes: pretreatment, introducing the object into the front mechanism to participate in the front dust removal treatment; gas mixing treatment, introducing the object output by the front mechanism into the gas mixing mechanism to participate in the slow flow and speed reduction treatment; purification treatment, introducing the object output by the gas mixing mechanism into the purification mechanism to participate in the plasma combustion purification treatment; cooling treatment, introducing the object output by the purification treatment into the cooling mechanism for cooling treatment; discharge treatment, discharging the object output by the cooling mechanism through the external discharge mechanism. This solution is not only complex in structure, but also requires combustion treatment, which has certain safety hazards.

[0006] There is also a proposal to add insulation function to the front vacuum pipeline and exhaust pipeline to maintain the high temperature of the pipeline, so as to achieve the purpose of suppressing the generation of particles. This method is more commonly used, such as Figure 3 The disadvantage of this method is that the particles generated in the chamber will still accumulate in the subsequent vacuum system, thereby increasing the burden on the vacuum system and failing to fundamentally solve the problem. Summary of the invention

[0007] The purpose of the present invention is to solve the key technical problem of how to collect particulate matter in the exhaust system in the semiconductor manufacturing field, and proposes a method for collecting residual gas particulate matter in semiconductor manufacturing. This method has the advantages of easy operation, all-weather, high collection efficiency and low cost.

[0008] The technical solution of the present invention is:

[0009] A method for collecting particles in a semiconductor process using plasma, the steps comprising:

[0010] 1) A horizontal exhaust channel is established between a vacuum chamber and a vacuum pump in a semiconductor manufacturing process, and a condensation module and a T-shaped pipe are sequentially arranged on the horizontal exhaust channel; a plasma generation module and a flow guide module are arranged in the horizontal section of the T-shaped pipe, and a dust collection module is arranged at the lower end outlet of the vertical section of the T-shaped pipe; and the inlet of the horizontal section of the T-shaped pipe is connected to the condensation module;

[0011] 2) The condensation module cools down the residual gas discharged from the vacuum chamber, promoting the condensation of substances in the waste gas into particles and then inputting them into the horizontal section of the T-shaped pipe;

[0012] 3) The plasma generating module discharges to generate plasma, forming a plasma region in the horizontal section of the T-shaped pipe, which is used to charge particles in the exhaust gas flowing through to form charged particles;

[0013] 4) The flow guide module generates an electric field for repelling the charged particles, guides the charged particles to the vertical section of the T-shaped pipe and into the dust collection module, and outputs the residual gas after the particles are filtered out through the outlet of the horizontal section of the T-shaped pipe;

[0014] 5) The horizontal section outlet of the T-shaped pipe is connected to the vacuum pump via an exhaust pipe, so as to discharge the gas outputted through the outlet of the horizontal section through the vacuum pump.

[0015] Furthermore, the plasma generation module and the flow guide module are the same metal grid; the metal grid is electrically connected to a power source located outside the T-shaped pipe to provide negative pressure for the metal grid.

[0016] Furthermore, the metal grid is placed obliquely at an angle of 45° in the T-shaped pipe; the mesh radius of the metal grid is 3 mm, and the mesh wire thickness is 1 mm.

[0017] Furthermore, the metal grid is an elliptical metal grid with a major axis of 170 mm and a minor axis of 120 mm; the inner diameter of the T-shaped pipe is 160 mm, the outer diameter is 165 mm, the horizontal section is 300 mm long, and the vertical section is 150 mm long; the lower end of the elliptical metal grid extends into the entrance of the vertical section.

[0018] Furthermore, the distance between the edge of the elliptical metal grid and the inner wall of the T-shaped pipe is 20 mm.

[0019] Furthermore, the power supply is a radio frequency power supply with a frequency of 13.56 MHz and a power between 1-200 W, or the power supply is an alternating current power supply.

[0020] Furthermore, the condensation module includes an air duct, which is a double-layer sleeve, and the interlayer of the double-layer sleeve serves as a water cooling channel.

[0021] A device for collecting particulate matter in a semiconductor process using plasma, characterized in that it comprises a condensation module, a plasma generation module, a flow guide module, a collection module and a T-shaped pipe; the condensation module and the T-shaped pipe are sequentially arranged between a vacuum chamber and a vacuum pump in a semiconductor manufacturing process as a horizontal exhaust channel, the plasma generation module and the flow guide module are arranged in the horizontal section of the T-shaped pipe, and the lower end outlet of the vertical section of the T-shaped pipe is connected to the dust collection module; the horizontal section inlet of the T-shaped pipe is connected to the condensation module, and the horizontal section outlet of the T-shaped pipe is connected to the vacuum pump via an exhaust pipe;

[0022] The condensation module is used to cool the residual gas discharged from the vacuum chamber, and promote the substances in the exhaust gas to condense into particles and then be input into the horizontal section of the T-shaped pipe;

[0023] The plasma generating module is used to discharge and generate plasma, forming a plasma region in the horizontal section of the T-shaped pipe, and charging particles in the exhaust gas flowing through to form charged particles;

[0024] The flow guide module is used to generate an electric field to repel the charged particles, guide the charged particles to the vertical section of the T-shaped pipe and into the dust collection module, and output the residual gas after filtering out the particles through the outlet of the horizontal section of the T-shaped pipe.

[0025] The present invention comprises a condensation module, a plasma generation module, a flow guide module and a collection module, wherein the condensation module, the plasma generation module and the flow guide module are integrated and arranged on the pipeline of the semiconductor manufacturing exhaust system, and the collection module is connected below the plasma generation module and the flow guide module.

[0026] The condensation module includes an air guide tube and a water cooling tube, which are installed behind the vacuum chamber exhaust port. The water cooling tube is wrapped around the air guide tube, and cold water is introduced into the lower tube port and flows out from the upper tube port. The chemical components in the residual gas accelerate condensation and grow into particles after cooling. Adding the condensation module in the present invention can improve the particle collection efficiency and reduce the pollutant components in the residual gas.

[0027] The plasma generation module is mainly used to generate uniform plasma in order to obtain a relatively uniform distribution of electrons and ions in space. When the particles in the residual gas flow through the plasma, the electrons and ions in the plasma will collide with the particles and adsorb on the surface of the particles to charge the particles. When the electron charging current and the ion charging current reach equilibrium, the amount of charge obtained by the particles reaches saturation. Since the mass of electrons is much smaller than the mass of ions, the thermal velocity of electrons is much greater than the thermal velocity of ions. Therefore, the particles usually end up being negatively charged. By adjusting the discharge parameters to change parameters such as electron density, the charge of the particles can ultimately be controlled. In short, the purpose of the plasma module is to generate uniform plasma and charge the particles passing through.

[0028] The flow guide module refers to a grid structure with a negative bias, which is characterized by an elliptical shape and is placed obliquely in the T-shaped pipe. The purpose is to use the negative bias of the grid itself to repel negatively charged particles and guide the particles in the exhaust pipe to the outlet below the T-shaped pipe. The flow guide module and the plasma generation module share a metal grid structure. When the particle flow is charged by the plasma module, the negatively charged particles will move along the surface of the grid structure under the repulsive effect of the electric field on the surface of the negatively biased grid structure. The residual gas particles generated in the semiconductor manufacturing vacuum chamber enter the exhaust pipe and have a uniform density distribution in the pipe. When the particles reach the flow guide module, they will move along the oblique grid structure to the outlet below the T-shaped pipe, so there are no more particles at the horizontal outlet of the pipe. After the particles flow through the flow guide module, they enter the collection module.

[0029] The main function of the collection module is to collect the particles from the diversion module by setting a metal cylindrical collection groove under the diversion module. According to actual needs, groove structures of different shapes and sizes can be set. The particles in the exhaust duct are affected by gravity and the repulsion of the metal grid with negative bias, moving from the surface of the grid to the bottom of the T-shaped pipe. After passing through the diversion module, they naturally fall into the groove of the collection module below to realize the collection of particles. The particles in the exhaust duct pass through these four modules in turn and are finally collected in the collection module. Since the plasma module and the diversion module themselves have negative bias, they repel negatively charged particles, so the particles will not pollute these two modules, that is, these two modules do not need to be cleaned. The collection module can be removed and cleaned regularly according to actual conditions.

[0030] The method of the present invention can theoretically collect particulate matter in the residual gas of the semiconductor manufacturing process with an efficiency of 100%, which can not only achieve green environmental protection and no particulate matter emission, but also protect the back-stage vacuum pump of the vacuum system to a great extent. The device designed by the method of the present invention can operate for a long time, and the equipment cost is very low.

[0031] The method of the present invention mainly comprises the following steps:

[0032] A. Set up a section of air guide pipe, which is connected to the semiconductor manufacturing process exhaust system pipeline by flange, and is tightly wrapped with a section of spiral water cooling pipe on the outside, and cold water is passed into the water cooling pipe to cool the residual gas discharged from the vacuum chamber. The air guide pipe and the water cooling pipe are made of metal to facilitate heat conduction.

[0033] B. A T-shaped pipe is provided, wherein the horizontal section of the T-shaped pipe is connected to the horizontal pipe between the air duct and the vacuum pump, wherein one end of the horizontal section of the T-shaped pipe is connected to the air duct via a flange, and the other end is connected to the vacuum pump via an exhaust pipe. A collecting tank is provided below the vertical section of the T-shaped pipe, and the collecting tank is connected to the outlet below the vertical section of the T-shaped pipe via a flange. The T-shaped pipe is made of glass, and the collecting tank is made of metal.

[0034] C. The T-shaped pipe contains a plasma generation module and a flow guide module. An elliptical metal grid is placed obliquely at the center of the T-shaped pipe, and a certain distance is kept between the edge of the metal grid and the T-shaped pipe. The metal grid is connected to an external power source of the T-shaped pipe. A certain voltage is first applied to the metal grid to discharge the gas nearby to generate plasma. At this time, the metal grid will automatically form a negative bias voltage, which can generate an electric field to repel negatively charged particles and form a flow guide effect. Therefore, the metal grid in the present invention serves as both a plasma generation module and a flow guide module.

[0035] D. Below the T-shaped pipe is a collection module, which is connected to the T-shaped pipe with a flange and is used to collect particulate matter guided by the metal grid.

[0036] E. Turn on the power system, and when the residual gas from the semiconductor manufacturing vacuum chamber flows into the T-shaped pipe through the gas guide pipe, the plasma generating module in the T-shaped pipe discharges the gas to generate uniform plasma. The required plasma is obtained by controlling the power of the power supply, etc. The metal grid is connected to an external power supply and has a negative bias voltage.

[0037] F. When the particles in the residual gas flow through the plasma area formed in the T-shaped pipe with the residual gas, the plasma quickly charges the particles, and the particles become electronegative. When the electronegative particles continue to move to the right with the gas flow and approach the negatively charged elliptical metal grid, the negatively charged particles are repelled by the electric field on the surface of the elliptical metal grid and move downward along the surface of the elliptical metal grid toward the outlet below the T-shaped pipe. When the particles flow to the outlet below the vertical section of the trapezoidal pipe, they enter the collection tank, completing the collection process of the particles in the residual gas.

[0038] G. After a certain working time, the collection tank is removed from the exhaust pipe, the particulate matter in the collection tank is cleaned, and the collection tank is installed back to the original position to continue the process of recovering the particulate matter in the residual gas.

[0039] The air guide tube described in step A can be replaced with a double-layer sleeve, and cold water is passed into the interlayer to directly contact the air guide tube to improve the cooling effect.

[0040] The pipe sizes described in steps A and B can be set according to the actual exhaust pipe sizes of the factory.

[0041] Step C sets an external power supply for the elliptical metal grid, the purpose of which is to generate uniform plasma by gas discharge near the elliptical metal grid. The power supply can use a radio frequency power supply with a frequency of 13.56MHz and a power between 1-200W, or a common AC power supply with a frequency of tens to tens of kilohertz. No matter which power supply is used, a certain negative bias voltage must be provided. The elliptical metal grid is placed obliquely in the horizontal section of the T-shaped pipe, filters the gas flowing through the horizontal section of the T-shaped pipe, and guides the particulate matter in the gas to the outlet below the vertical section of the T-shaped pipe.

[0042] The size of the collection tank described in step D can be set according to the particle recovery frequency. The larger the size, the more particles it can accommodate and the longer the continuous working time of the collection device. If necessary, an anti-backflow device can be added to the collection tank to prevent particles falling into the collection tank from being affected by the airflow and flying out of the collection tank.

[0043] After the plasma described in step E is generated, a quasi-neutral environment containing free electrons, ions and various other active substances will be formed in the region. When the particles approach the elliptical metal grid with the airflow, the surrounding free electrons and particles will collide with the particles and adhere to the particles to make them charged. Since the movement speed of free electrons is much greater than the movement speed of ions, the particles generally show negative charge after the charge reaches equilibrium.

[0044] The plasma generated in step F generates a non-neutral area on the surface of the elliptical metal grid, and a strong electric field is formed in the area, which can repel the negatively charged particles. After being repelled, the particles move along the inclined direction of the elliptical metal grid, cannot pass through the metal grid, and move along the outlet below the T-shaped pipe instead.

[0045] The plasma generated in step F contains electrons, positive ions, negative ions, and various active groups. When the particles enter the plasma, since the mass of electrons is much smaller than the mass of other particles and the speed of electron movement is much greater than the speed of other particles, the electrons first reach and adsorb on the surface of the particles. When the electron charging current and the charging current of other particles reach equilibrium, the charge of the particles basically reaches a steady state and is electronegative.

[0046] Step F is to utilize the surface electric field of the elliptical metal grid to guide the negatively charged particles into the collection tank below the T-shaped pipe to complete the collection.

[0047] The advantages of the present invention are as follows:

[0048] The present invention arranges a T-shaped pipe in series on the horizontal exhaust pipe between the semiconductor process vacuum chamber and the back-stage vacuum pump, arranges an elliptical metal wire mesh at the center of the T-shaped pipe, and is placed obliquely in the T-shaped pipe. When the particles flow through the plasma area with the residual gas, the electrons in the plasma charge the particles, making the particles negatively charged; when the negatively charged particles flow through the charged elliptical metal wire (net), they are repelled by the surface electric field and guided to move along the surface of the elliptical metal wire (net) to the lower pipe, and finally enter a collection tank arranged below it, so as to realize the collection of particles. The method of the present invention is simple and convenient to operate. The efficiency of collecting particles in the residual gas of semiconductor manufacturing can reach 100% in theory, and the actual measured efficiency is 98%. It is not only green and environmentally friendly, without particle emission, but also can effectively protect the exhaust pipeline and the back-stage vacuum pump and other equipment. The residual gas particle collection device designed by the method has low cost and can be continuously operated in a factory, solving the current problem of residual gas particle pollution in semiconductor manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1This is a schematic diagram of a vacuum system in semiconductor manufacturing.

[0050] Figure 2 Schematic diagram of the vacuum system for adding filtration equipment.

[0051] Figure 3 Schematic diagram of the vacuum system for added insulation function.

[0052] Figure 4 It is a structural schematic diagram of the present invention.

[0053] Figure numerals: 1-semiconductor process chamber; 2-air duct; 3-water cooling pipe; 4-particles; 5-T-type pipe; 6-elliptical metal grid; 7-radio frequency (AC) negative pressure power supply; 8-collecting tank; 9-exhaust pipe; 10-vacuum pump. DETAILED DESCRIPTION

[0054] The present invention is further described in detail below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention but not to limit the scope of the present invention.

[0055] The device for collecting particles in semiconductor process by using plasma provided by the present invention is as follows: Figure 4 As shown, the collection method specifically includes the following steps:

[0056] The particles in the semiconductor process chamber 1 will be drawn out with the exhaust gas, passing through the air duct 2, which has an inner diameter of 160mm, an outer diameter of 165mm, and a length of 400mm. The water cooling tube 3 cools the exhaust gas, and the particles 4 condense and grow more, and then flow into the adjacent T-shaped pipe 5. The T-shaped pipe 5 has an inner diameter of 160mm and an outer diameter of 165mm. It is made of glass material, with a horizontal section length of 300mm and a vertical section length of 150mm. The upper end of the vertical section is connected to the center of the horizontal section. An elliptical metal grid 6 is placed at an angle of 45° to the horizontal direction in the T-shaped pipe 5. The long axis of the elliptical metal grid 6 is 170mm and the short axis is 120mm. Its edge is 20mm away from the horizontal section of the T-shaped pipe 5, and the lower end slightly penetrates into the vertical section entrance of the T-shaped pipe 5. The elliptical metal grid 6 is connected to the external radio frequency power supply 7 through the reserved hole on the wall of the T-shaped pipe 5 with a wire wrapped in an insulating layer and sealed. The power of the radio frequency power supply 7 is 80W and the frequency is 13.56MHz. After the residual gas is discharged from the vacuum chamber and the radio frequency power supply 7 is powered on, a uniform plasma can be generated on the side of the elliptical metal grid.

[0057] A collecting tank 8 is arranged below the T-shaped pipe 5. The connection between the T-shaped pipe 5 and the collecting tank 8 is connected by a flange. The inner and outer radii of the collecting tank are consistent with the caliber of the vertical section of the T-shaped pipe, which are 160 mm and 165 mm. The collecting tank is 200 mm deep.

[0058] The horizontal section outlet of the T-shaped pipe 5 is connected to the vacuum pump 10 by means of an exhaust pipe 9 and a flange, and the residual gas after the collected particulate matter is discharged through the vacuum pump 10.

[0059] During operation, the external RF power supply 7 is turned on, and a uniform plasma is generated near the elliptical metal grid 6. The residual gas and particulate matter 3 flowing out of the semiconductor process chamber 1 pass through the air guide tube 2, cool down to promote the growth of the particulate matter, and then enter the T-shaped pipe 5. When the particulate matter passes through the plasma near the elliptical metal grid 6, it will absorb a large amount of charge. Since the movement speed of electrons is greater than the movement speed of ions, the particulate matter will carry negative charge when the charge reaches stability. The negatively charged particulate matter will be repelled by the electric field on the surface of the negative potential elliptical metal grid 6, move to the pipe below the T-shaped pipe 5, and then fall into the collection tank 8, while the residual gas will not be affected when passing through the metal grid 6.

[0060] The metal grid 6 plays a decisive role in the collection of residual gas particles. Therefore, special attention should be paid to the size and placement of the metal grid 6. On the one hand, the inclination angle of the metal grid must be large to ensure that the particles in the residual gas have enough time to enter the lower channel of the T-shaped pipe 5 under the guidance of the metal grid. On the other hand, the hole radius of the metal grid 6 should not be greater than 5mm to ensure that the particles can be intercepted and guided by the metal grid with little impact on the airflow. If necessary, the metal grid can be made into an arc shape to facilitate the diversion. After testing, we determined that the hole radius of the metal grid is 3mm and the mesh wire thickness is 1mm, which is better.

[0061] The particles falling into the collection tank 8 should be recovered and cleaned regularly. If an appropriate amount of adsorbent is added to the collection tank to reduce the particles, the collection efficiency of the particles will be higher.

[0062] In this embodiment, the collection efficiency is tested by taking the continuous addition of pine pollen particles. In the experiment, the air pressure of the system is maintained at 80 Pa, and 4.869 grams of pine pollen particles with an average particle size of about 40 microns are evenly and slowly sprinkled into the process chamber 1. Most of these particles are effectively collected by the method and enter the collection tank 8. After the experiment, the particles in the collection tank 8 are measured to be 4.767 grams, and the collection efficiency is 98%.

[0063] The present invention uses a plasma environment to charge the residual gas particles in semiconductor manufacturing, and then achieves the purpose of collecting the particles in the residual gas by controlling the movement of the residual gas particles. The equipment used in the present invention has a simple structure and can be used sustainably, has low cost, is environmentally friendly and energy-saving, can be easily installed in the tail gas treatment pipeline process, has high efficiency in collecting particles, and has great significance for industrial production and environmental protection.

[0064] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0065] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above, and that the present application can be implemented in other specific forms without departing from the spirit or essential features of the present application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present application. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for collecting particulate matter in a semiconductor process using plasma, the steps comprising: 1) A horizontal exhaust channel is established between a vacuum chamber and a vacuum pump in a semiconductor manufacturing process, and a condensation module and a T-shaped pipe are sequentially arranged on the horizontal exhaust channel; a plasma generation module and a flow guide module are arranged in the horizontal section of the T-shaped pipe, and a dust collection module is arranged at the lower end outlet of the vertical section of the T-shaped pipe; and the inlet of the horizontal section of the T-shaped pipe is connected to the condensation module; 2) The condensation module cools down the residual gas discharged from the vacuum chamber, promotes the condensation of substances in the waste gas into particles, and then inputs them into the horizontal section of the T-shaped pipe; 3) The plasma generating module discharges to generate plasma, forming a plasma region in the horizontal section of the T-shaped pipe, which is used to charge particles in the exhaust gas flowing through to form charged particles; 4) The flow guide module generates an electric field for repelling the charged particles, guides the charged particles to the vertical section of the T-shaped pipe and enters the dust collection module, and outputs the residual gas after the particles are filtered out through the outlet of the horizontal section of the T-shaped pipe; wherein the plasma generation module and the flow guide module are the same metal grid; the metal grid is electrically connected to a power source located outside the T-shaped pipe to provide negative pressure for the metal grid; 5) The outlet of the horizontal section of the T-shaped pipe is connected to the vacuum pump via an exhaust pipe, so as to discharge the gas outputted through the outlet of the horizontal section through the vacuum pump.

2. The method according to claim 1, characterized in that The metal grid is placed obliquely in the T-shaped pipe at an angle of 45°; The mesh radius of the metal grid is 3 mm, and the mesh wire thickness is 1 mm.

3. The method according to claim 1, characterized in that The metal grid is an elliptical metal grid with a major axis of 170 mm and a minor axis of 120 mm; the inner diameter of the T-shaped pipe is 160 mm, the outer diameter is 165 mm, the horizontal section is 300 mm long, and the vertical section is 150 mm long; the lower end of the elliptical metal grid extends into the entrance of the vertical section.

4. The method according to claim 3, characterized in that: The distance between the edge of the elliptical metal grid and the inner wall of the T-shaped pipe is 20 mm.

5. The method according to claim 1, characterized in that The power source is a radio frequency power source with a frequency of 13.56 MHz and a power between 1 and 200 W, or the power source is an alternating current power source.

6. The method according to claim 1, characterized in that The condensation module includes an air duct, which is a double-layer sleeve, and the interlayer of the double-layer sleeve serves as a water cooling channel.

7. A device for collecting particulate matter in a semiconductor process using plasma, characterized in that: It comprises a condensation module, a plasma generation module, a flow guide module, a collection module and a T-shaped pipe; the condensation module and the T-shaped pipe are sequentially arranged between a vacuum chamber and a vacuum pump in a semiconductor manufacturing process as a horizontal exhaust channel, the plasma generation module and the flow guide module are arranged in the horizontal section of the T-shaped pipe, and the lower end outlet of the vertical section of the T-shaped pipe is connected to the dust collection module; the horizontal section inlet of the T-shaped pipe is connected to the condensation module, and the horizontal section outlet of the T-shaped pipe is connected to the vacuum pump via an exhaust pipe; The condensation module is used to cool the residual gas discharged from the vacuum chamber, and promote the condensation of substances in the exhaust gas into particles and then input them into the horizontal section of the T-shaped pipe; The plasma generating module is used to discharge and generate plasma, forming a plasma region in the horizontal section of the T-shaped pipe, and charging particles in the exhaust gas flowing through to form charged particles; The flow guide module is used to generate an electric field to repel the charged particles, guide the charged particles to the vertical section of the T-shaped pipe and into the dust collection module, and output the residual gas after the particles are filtered out through the outlet of the horizontal section of the T-shaped pipe; Wherein, the plasma generation module and the flow guide module are the same metal grid; the metal grid is electrically connected to a power source located outside the T-shaped pipe to provide negative pressure for the metal grid.

8. The device according to claim 7, characterized in that The metal grid is placed obliquely in the T-shaped pipe at an angle of 45°; The mesh radius of the metal grid is 3 mm, and the mesh wire thickness is 1 mm.

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