Vacuum valve and deposition system

Abstract

The utility model discloses a vacuum valve and a deposition system. The vacuum valve comprises an airflow pipeline, a movable part and a coil. The movable part is movably arranged in the airflow pipeline. The coil is wound around the periphery of the airflow pipeline and used for applying an alternating magnetic field into the airflow pipeline. By means of the mode, blocking generated when the vacuum valve is used can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor, in particular to a vacuum valve and a deposition system. BACKGROUND

[0002] In the related art, a semiconductor thin film deposition system generally comprises a reaction device, a negative pressure pump connected with the reaction device, and a tail gas treatment device. A vacuum valve can be arranged between the reaction device and the negative pressure pump to adjust the suction of the negative pressure pump. During the deposition process, the discharge of the tail gas can cause the deposition of a thin film in the vacuum valve, which can easily cause the blockage of the vacuum valve. CONTENT OF THE INVENTION

[0003] Embodiments of the present application provide a vacuum valve and a deposition system, which can reduce the blockage of the vacuum valve during use.

[0004] In a first aspect, embodiments of the present application provide a vacuum valve. The vacuum valve comprises an airflow duct, a movable member, and a coil. The movable member is movably arranged in the airflow duct. The coil is arranged around the outer periphery of the airflow duct and is used to apply an alternating magnetic field to the airflow duct.

[0005] Optionally, the diameter of the coil is 1mm-3mm, and the number of turns of the coil is more than 50 turns.

[0006] Optionally, the airflow duct comprises a first duct and a second duct with different extension directions, the first duct and the second duct are connected by a connecting duct, the movable member is movably arranged in the connecting duct, and the coil is arranged around the first duct, the second duct, and the connecting duct.

[0007] Optionally, at least part of the airflow duct is made of an insulating material.

[0008] Optionally, the insulating material can be ceramic or quartz.

[0009] Optionally, the coil is arranged around the outer periphery of the airflow duct made of the insulating material.

[0010] Optionally, the movable member can move, rotate, or oscillate relative to the airflow duct.

[0011] Optionally, the airflow duct is provided with a cleaning inlet and a cleaning outlet, the cleaning inlet is used for the cleaning ball to enter the airflow duct, and the cleaning outlet is used for the gas to be discharged from the airflow duct.

[0012] In a second aspect, embodiments of the present application provide a deposition system. The deposition system comprises a reaction device, a negative pressure pump, and a tail gas treatment device connected in series. The deposition system further comprises the above-mentioned vacuum valve connected in series between the reaction device and the negative pressure pump. The deposition system further comprises a radio frequency device matchedly connected with the coil of the vacuum valve.

[0013] Optionally, the deposition system further comprises a radio frequency device, which is connected with the vacuum valve and / or the coil of the reaction device.

[0014] The beneficial effect of the present application is that, different from the prior art, by arranging the coil outside the air flow pipeline, when the radio frequency current flows through the coil, an alternating magnetic field is generated inside the vacuum valve, and the alternating magnetic field can generate an electric field through inductive coupling, which is sufficient to ionize the cleaning gas. After the cleaning gas is ionized, the thin film deposited in the vacuum valve can be etched, thereby reducing the blockage of the vacuum valve caused by the thin film. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a structural schematic diagram of the deposition system of the present application;

[0016] Figure 2 is a structural schematic diagram of the vacuum valve of the present application;

[0017] Figure 3 is a structural schematic diagram of another embodiment of the vacuum valve of the present application;

[0018] Figure 4 is a flowchart of the cleaning method of the deposition system of the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0020] The embodiments of the present application provide a deposition system 1, which aims to improve the efficiency and quality of the thin film deposition process, while reducing the equipment maintenance time and cost. The deposition system 1 can apply different deposition technologies, for example, any one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), which are not limited here. As shown in the figure, the deposition system 1 comprises a reaction device 10, a negative pressure pump 30 and an exhaust treatment device 40 connected in series. Figure 1 The reaction device 10 has a reaction cavity, in which different process gases can be introduced. The inside of the reaction cavity is where the deposition process takes place, which is usually a highly vacuum environment to ensure the purity of the deposition process. Under the action of the radio frequency field, the process gas can be ionized to react with the surface of the substrate to achieve the purpose of depositing a thin film. The reaction cavity can also introduce a cleaning gas to clean and purge the reaction cavity.

[0021] The negative pressure pump 30 can provide negative pressure, on one hand, the negative pressure pump 30 can suck different types of process gas, on the other hand, the negative pressure pump 30 can also suck the gas in the reaction cavity to maintain sufficient vacuum degree.

[0022] The tail gas treatment device 40 can treat the sucked tail gas to realize resource recovery and harmless treatment. The tail gas treatment device can include a filtering system, a cold trap or a heating system, etc., which are not limited here.

[0023] The deposition system 1 can also include a gas delivery system. The gas delivery system can include, for example, a gas source, a mass flow controller, a pneumatic valve and a pipeline, for accurately controlling the flow and proportion of the reaction gas.

[0024] The deposition system 1 also includes a vacuum valve 20 connected in series between the reaction device 10 and the negative pressure pump 30. The vacuum valve 20 can move the movable part 22 by driving operation to control the opening or closing of the passage, so as to accurately regulate the gas flow. The vacuum valve 20 can adjust the on-off of the passage between the reaction device 10 and the negative pressure pump 30, and can also adjust the suction force of the negative pressure pump 30 by changing the cross section of the passage.

[0025] The deposition system 1 also includes a radio frequency device (not shown in the figure), which is connected with the coil 23 of the vacuum valve 20. After the radio frequency device is connected with the coil 23, the radio frequency current can be applied to the coil 23. The coil 23 can generate an alternating magnetic field under the action of the radio frequency current, and the alternating magnetic field can generate an alternating electric field in the surrounding space after inductive coupling. The cleaning gas can be ionized under the action of the alternating electric field. In the inductively coupled plasma (ICP), the maintenance of the plasma depends on the energy continuously provided by the induction coil. The alternating magnetic field generated by the induction coil excites an induced current in the plasma. The resistance of these currents is very small, so the current is very large, which can generate high temperature, further heat and ionize the gas, and form a stable plasma torch. The ionized cleaning gas can etch the film in the vacuum valve 20 to reduce the plugging caused by the film. The structure of the vacuum valve 20 will be exemplarily introduced below.

[0026] In combination with Figure 2 and Figure 3The embodiment of the present application provides a vacuum valve 20. The vacuum valve 20 comprises an airflow pipe 21, a movable element 22 and a coil 23. The vacuum valve 20 can be a butterfly valve, a ball valve, an angle valve, a diaphragm valve, a needle valve, a flap valve or an electromagnetic vacuum valve. The airflow pipe 21 can be used for flowing of cleaning gas. The movable element 22 is movably arranged in the airflow pipe 21. The movable element 22 can block the airflow pipe 21 or limit the flow of the airflow pipe 21 by movement. The coil 23 is arranged around the outer periphery of the airflow pipe 21 and used for applying an alternating magnetic field to the airflow pipe 21. According to the type of the vacuum valve 20, the movable element 22 can be a valve plate, a valve ball, a valve rod, a diaphragm, a needle-shaped part or a flat gate.

[0027] By arranging the coil 23 around the outer periphery of the airflow pipe 21, when the radio frequency current flows through the coil 23, the alternating magnetic field is generated in the vacuum valve 20. The alternating magnetic field can generate an electric field sufficient to ionize the cleaning gas through inductive coupling. After the cleaning gas is ionized, the thin film deposited in the vacuum valve 20 can be etched, so as to reduce the blockage of the vacuum valve 20 caused by the thin film.

[0028] In some embodiments, the movable element 22 can move, rotate or swing relative to the airflow pipe 21. The movable element 22 can block the airflow pipe 21 or limit the flow of the airflow pipe 21 by moving, rotating or swinging relative to the airflow pipe 21. In other words, the vacuum valve 20 can be a gate valve, a swing valve or a butterfly valve.

[0029] In some embodiments, in order to generate sufficient alternating magnetic field under the radio frequency current, the diameter of the coil 23 is 1mm-3mm, and the number of turns of the coil 23 is more than 50 turns.

[0030] In some embodiments, the coil 23 is arranged around the outer periphery of the airflow pipe 21. Figure 2The airflow pipe 21 comprises a first pipe 211 and a second pipe 212 with different extending directions, and the first pipe 211 and the second pipe 212 are connected by a connecting pipe 213. The movable element 22 is movably arranged on the connecting pipe 213, and the coil 23 is arranged around the first pipe 211, the second pipe 212 and the connecting pipe 213. The first pipe 211 and the second pipe 212 have different extending directions, so that the vacuum valve 20 can change the airflow direction. The movable element 22 cooperates with the connecting pipe 213, so that the airflow pipe 21 can be blocked or the flow of the airflow pipe 21 can be limited. The coil 23 can apply an alternating magnetic field to the inside of the airflow pipe 21 by being arranged around the first pipe 211, the second pipe 212 and the connecting pipe 213. The coil 23 corresponding to the first pipe 211, the second pipe 212 and the connecting pipe 213 can be the same coil 23. The first pipe 211, the second pipe 212 and the connecting pipe 213 can also correspond to different coils 23, and the different coils 23 can have the same or different diameters and numbers of turns.

[0031] In some embodiments, the coil 23 can be arranged around the outer periphery of the airflow pipe 21 in a spiral manner. In other embodiments, the outer periphery of the airflow pipe 21 can be spaced apart to be provided with a plurality of coils 23, and each coil 23 can be individually connected to a power source to generate a magnetic field. The magnetic pole direction of each coil 23 can be arranged along the radial direction of the airflow pipe 21. The plurality of coils 23 can cooperate to generate an alternating magnetic field in the airflow pipe 21.

[0032] In some embodiments, the airflow pipe 21 is made of an insulating material. The insulating material can be, for example, ceramic or quartz. The airflow pipe 21 can also be made by depositing or coating an insulating material on the outer surface of a conventional metal material, so that the airflow pipe 21 has sufficient strength and can meet the process requirements of the embodiments of the present application. In some embodiments, the part of the airflow pipe 21 corresponding to the movable element 22 is made of an insulating material. In addition, the coil 23 is arranged around the outer periphery of the airflow pipe 21 made of an insulating material. In this way, other parts of the airflow pipe 21 can still use metal materials in the vacuum valve 20 technology, so that the demand for ionized cleaning gas in the embodiments of the present application can be met, and the overall strength of the airflow pipe 21 can be improved.

[0033] In other embodiments, the entire airflow pipe 21 can be made of an insulating material. Further, the vacuum valve 20 further comprises a main pipe made of a metal material, and the main pipe is connected to any one end of the airflow pipe 21. Alternatively, the main pipe is connected to both ends of the airflow pipe 21.

[0034] In some embodiments, the gas flow pipe 21 can also be provided with a cleaning inlet and a cleaning outlet, and the cleaning gas can also flow through the cleaning inlet and the cleaning outlet of the gas flow pipe 21. In the deposition system 1 provided by the embodiments of the present application, the cleaning of the vacuum valve 20 requires the injection of the cleaning gas. In the case where the reaction device 10 and the vacuum valve 20 need to be cleaned at the same time, the cleaning of the reaction device 10 and the cleaning of the vacuum valve 20 can be completed at the same time by starting the entire deposition system 1. However, if the vacuum valve 20 needs to be cleaned alone, starting the entire deposition system 1 will cause waste of resources and time. By providing the cleaning inlet and the cleaning outlet on the vacuum valve 20, the cleaning gas can be injected into the vacuum valve 20 through the cleaning inlet and the cleaning outlet when the deposition system 1 is not started, and then the magnetic field generated by the coil 23 is controlled alone to clean the vacuum valve 20.

[0035] Optionally, the gas flow pipe 21 can also not be provided with the cleaning outlet, but the gas after the cleaning of the vacuum valve 20 can be processed by the negative pressure pump 30 and the tail gas treatment device 40 of the above embodiments.

[0036] In combination Figure 4 , the embodiments of the present application also provide a cleaning method of the deposition system 1. The method comprises:

[0037] S10: turn on the radio frequency power supply and the vacuum valve 20.

[0038] The deposition system 1 performs deposition work in the reaction device 10 during the non-cleaning period. In different deposition processes, the radio frequency power supply and the vacuum valve 20 can be in an open state or can be in a closed state. After the deposition system 1 enters the cleaning period, the radio frequency power supply and the vacuum valve 20 are turned on to prepare for the cleaning of the deposition system 1.

[0039] S20: inject the cleaning gas into the deposition system 1 and make it pass through the vacuum valve 20. The cleaning gas includes carrier gas and reaction gas.

[0040] The cleaning gas can be discharged through the vacuum valve 20. After the radio frequency power supply and the vacuum valve 20 are turned on, an alternating magnetic field can be generated in the gas flow pipe 21 of the vacuum valve 20 under the action of the coil 23. The magnetic field generates a time-varying electric field through inductive coupling, and the inductive coupling electric field can accelerate electrons and produce ionization collisions, and a high-density plasma is generated when the cleaning gas passes through. Under the action of the plasma, the thin film deposited in the vacuum valve 20 can be etched, thereby cleaning the vacuum valve 20 and preventing plugging.

[0041] In some embodiments, the carrier gas is argon, and the reaction gas includes nitrogen, oxygen, and nitrogen trifluoride. The thin film deposited by the vacuum valve 20 is a carbon film. After the nitrogen, oxygen, and nitrogen trifluoride are ionized, they can react with the carbon film. After the carbon film remaining in the vacuum valve 20 is etched, the valve clogging caused by the carbon film can be eliminated.

[0042] In some embodiments, the flow rate of argon is 100-2000 sccm, such as 500 sccm, 800 sccm, 1300 sccm, or 1600 sccm. The flow rate of nitrogen is 100-500 sccm, such as 160 sccm, 230 sccm, 340 sccm, or 450 sccm. The flow rate of oxygen is 1000-7000 sccm, such as 2300 sccm, 3400 sccm, 4500 sccm, or 5600 sccm. The flow rate of nitrogen trifluoride is 100-2000 sccm, such as 500 sccm, 800 sccm, 1300 sccm, or 1600 sccm.

[0043] In one embodiment, the inventors of the present application found that, when the pressure is controlled at 2 torr, the flow rate of oxygen is 3000 sccm, and the temperature is 180°C, the cleaning efficiency under these conditions is greater than 0.1 (Angstrom / second) by cleaning the surface of a sample slice placed in the vacuum valve 20. (angstrom / second). It is proved that, in the above embodiments of the present application, the vacuum valve 20 can be effectively cleaned.

[0044] In summary, by using this method, the cleaning efficiency of the vacuum valve 20 is improved, and the equipment maintenance and downtime caused by carbon film clogging are reduced, thereby significantly improving the stability and production efficiency of the semiconductor manufacturing process. In addition, in the part corresponding to the gas flow pipe 21 and the movable part 22, the insulating material such as the ceramic ring is used instead of the traditional metal ring, which can also improve the corrosion resistance and high temperature resistance of the vacuum valve 20, and further prolong the service life of the equipment. The embodiments of the present application provide an efficient and reliable cleaning and maintenance method for the vacuum valve 20 in the semiconductor manufacturing industry.

[0045] The above is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. A vacuum valve, characterized in that The vacuum valve comprises: a gas flow pipe; a movable element movably arranged in the gas flow pipe; a coil arranged around at least a part of the outer periphery of the gas flow pipe for applying an alternating magnetic field to the gas flow pipe.

2. The vacuum valve according to claim 1, wherein: the diameter of the coil is 1-3 mm, and the number of turns of the coil is more than 50.

3. The vacuum valve according to claim 1, wherein: the gas flow pipe comprises a first pipe and a second pipe having different extension directions, the first pipe and the second pipe are connected by a connecting pipe, the movable element is movably arranged in the connecting pipe, and the coil is arranged around the first pipe, the second pipe and the connecting pipe.

4. The vacuum valve according to any one of claims 1-3, wherein: at least a part of the gas flow pipe is made of an insulating material.

5. The vacuum valve according to claim 4, wherein: the insulating material can be ceramic or quartz.

6. The vacuum valve according to claim 4, wherein: the coil is arranged around the outer periphery of the gas flow pipe made of the insulating material.

7. The vacuum valve according to claim 1, wherein: the movable element can move, rotate or swing relative to the gas flow pipe.

8. The vacuum valve according to claim 1, wherein: the gas flow pipe is provided with a cleaning inlet for the cleaning ball to enter the gas flow pipe and a cleaning outlet for the gas to be discharged from the gas flow pipe.

9. A deposition system, characterized by, The deposition system comprises, in sequence, a reaction device, a negative pressure pump and a tail gas treatment device, and further comprises the vacuum valve according to any one of claims 1-8, which is connected in series between the reaction device and the negative pressure pump.

10. The deposition system according to claim 9, wherein: the deposition system further comprises a radio frequency device which is connected in matching with the coil of the vacuum valve and / or the reaction device. ​

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