Turbo molecular pump
By designing a small angle between the exhaust port and the shaft and a gas heating device in a turbomolecular pump, combined with a conical rotor cover, the polymer accumulation problem is solved, the exhaust efficiency and service life are improved, and the maintenance cost is reduced.
Patent Information
- Application Number
- CN202422512138.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-16
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-10-16
AI Technical Summary
In the wafer process, the polymer of the turbomolecular pump is prone to accumulate, resulting in a decrease in wafer yield, a short service life of the turbomolecular pump and a safety hazard. The existing technology is difficult to effectively solve.
The exhaust port of the turbomolecular pump is designed to form an angle of less than or equal to 30 degrees axially with the rotating shaft, and a gas heating device is added at the exhaust port to form a vortex current, combined with the conical rotor cover design, reducing polymer accumulation.
It improves the exhaust efficiency of turbomolecular pumps, reduces polymer accumulation, extends overhaul life, reduces maintenance costs, and improves operating time.
Smart Images
Figure CN223120198U_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present application relate to the field of semiconductor technology, and particularly to a turbo molecular pump. Background Art
[0002] In the manufacturing process of wafers, for example, in the existing dry etching process technology, during the etching process, the etching chamber requires an ultra-high vacuum environment. Etching machines are equipped with a turbo molecular pump and a dry pump to operate together to meet the conditions of the etching process. The gas flow and the generated polymer during the etching process are discharged through the turbo molecular pump. During the use of the turbo molecular pump, the generated polymer is likely to accumulate at the bottom of the turbo molecular pump, affecting the yield of wafers, even causing them to be scrapped, resulting in a short service life of the turbo molecular pump and prone to safety hazards. Summary of the Utility Model
[0003] In view of this, the embodiments of the present application provide a turbo molecular pump, which includes: a housing provided with a receiving cavity, including an air inlet port and an exhaust port; a rotating shaft disposed in the receiving cavity; a first end of the rotating shaft is close to the air inlet port, and a second end of the rotating shaft is close to the exhaust port; the extending direction of the exhaust port is parallel to the axial direction of the rotating shaft; or, there is a first included angle between the extending direction of the exhaust port and the axial direction of the rotating shaft; the first included angle is less than or equal to 30 degrees; a plurality of rotors distributed along the axial direction of the rotating shaft; each rotor is distributed circumferentially along the rotating shaft; wherein, when the rotating shaft rotates, the rotating shaft drives the plurality of rotors to move together to drive the air flow in the receiving cavity to flow from the air inlet port to the exhaust port.
[0004] In some embodiments, the turbo molecular pump further includes a gas heating device; the gas heating device is connected to the exhaust port along the extending direction of the exhaust port, and is used to heat the air flow flowing into the cavity of the gas heating device from the exhaust port, so that the air flow flowing into the cavity of the gas heating device forms a vortex and flows out of the gas heating device.
[0005] In some embodiments, the gas heating device includes a gas inlet pipe and a heating channel; the gas inlet direction of the gas inlet pipe has an included angle with the air flow flowing into the cavity of the gas heating device and is deviated from the center of the cavity of the gas heating device for forming a vortex; the heating channel is used to heat the air flow flowing in from the exhaust port and the air flow flowing in from the gas inlet pipe.
[0006] In some embodiments, the turbo molecular pump further includes a rotor cover; the rotor cover is disposed in the receiving cavity and close to the first end, and includes a conical part; the bottom surface of the conical part is close to the first end, and the top end of the conical part is far from the first end; the bottom surface of the conical part at least covers the first end; wherein, when the rotating shaft rotates, the rotor cover remains relatively stationary.
[0007] In some embodiments, there is a second included angle between the bottom surface and the side surface of the conical part; the range of the second included angle is 15 degrees to 75 degrees.
[0008] In some embodiments, the conical part includes a cone or a pyramid.
[0009] In some embodiments, the bottom surface of the conical part covers the first end and covers a part of the rotor.
[0010] In some embodiments, the turbomolecular pump further includes a gas supplement port; the gas supplement port is connected to the accommodation cavity for supplementing the gas in the accommodation cavity to meet the air pressure working condition of the turbomolecular pump.
[0011] In some embodiments, the turbomolecular pump further includes a driving unit; the driving unit is connected to the rotating shaft for driving the rotating shaft to rotate; the driving unit is close to the second end.
[0012] In some embodiments, the turbomolecular pump further includes an opening and closing device, which is arranged on the side of the housing close to the chamber, and the turbomolecular pump is communicated with the chamber through a communication channel; the opening and closing of the opening and closing device control the opening and closing of the communication channel; wherein, when the communication channel is opened and the rotating shaft rotates, the rotating shaft drives a plurality of rotors to move together to drive the airflow in the chamber to flow through the communication channel to the accommodation cavity.
[0013] In each embodiment of the present application, there is a first included angle (the first included angle is less than or equal to 30 degrees) between the extending direction of the exhaust port and the axial direction of the rotating shaft, which can be understood as that the included angle between the extending direction of the exhaust port and the airflow direction in the accommodation cavity is small; or, the extending direction of the exhaust port is parallel to the axial direction of the rotating shaft, which can be understood as that the extending direction of the exhaust port is equivalent to the airflow direction in the accommodation cavity. This can greatly improve the exhaust efficiency of the turbomolecular pump, greatly reduce the polymer accumulation speed in the turbomolecular pump, improve the particulate mask defects of the product, increase the overhaul life of the turbomolecular pump while reducing the maintenance cost, and improve the running time of the turbomolecular pump. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a cross-sectional view of the first turbomolecular pump provided by the embodiment of the present application and a schematic diagram of the airflow direction and polymer situation in the accommodation cavity of the first turbomolecular pump;
[0015] Figure 2 It is a cross-sectional view of the second turbomolecular pump provided by the embodiment of the present application;
[0016] Figure 3 It is a cross-sectional view of the third turbomolecular pump provided by the embodiment of the present application;
[0017] Figure 4The cross-sectional schematic diagram of the fourth turbo molecular pump provided by the embodiment of the present application;
[0018] Figure 5 is Figure 4 the cross-sectional schematic diagram of the gas heating device;
[0019] Figure 6 is Figure 4 the schematic diagram of the gas flow direction and polymer situation in the accommodation cavity;
[0020] Figure 7 is Figure 4 the schematic diagram of the deformation situation of the rotor cover; Detailed implementation manners
[0021] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the embodiments of the present application and the accompanying drawings. The described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.
[0022] In the drawings, for clarity, the dimensions of components, devices, units and their relative dimensions may be exaggerated. The same reference numerals represent the same elements throughout.
[0023] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present application. When used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, determine the presence of the described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. When used herein, the term "and / or" includes any and all combinations of the related listed items.
[0024] Refer to Figure 1, during the use of a turbomolecular pump, the rotor cover 114 of the turbomolecular pump 100 is designed as a flat surface, and there is a probability that the polymers generated during the etching process will be lifted. Moreover, the included angle between the extending direction D2 of the exhaust port 106 of the turbomolecular pump and the air flow direction D4 in the accommodating cavity is relatively large, such as 90 degrees, and the generated polymer P1 is likely to accumulate at the bottom of the turbomolecular pump; on the process level, particle masking defects will deteriorate as the polymer P1 accumulates at the bottom of the turbomolecular pump, and ultimately the yield of the wafer will decrease or even be scrapped. For example, during the high and low pressure conversion process of the etching process, there is a probability that the polymer P1 at the bottom of the turbomolecular pump will be lifted to the position of the intake port 104, and the polymer P2 at the position of the intake port 104 will fall onto the surface of the wafer, causing particle masking defects; on the equipment level, it will lead to a shorter overhaul life of the turbomolecular pump and affect the operation time of the etching machine. It should be noted that, Figure 1 The reference numerals shown in Figure 2 and Figure 3 should be understood with reference to the corresponding components, devices, and units with the same reference numerals, and detailed descriptions are provided here. Figure 1 The dimensions of the components, devices, and units described in Figure 2 and Figure 3 can also be understood with reference to the corresponding components, devices, and units. For example, the intake port and the exhaust port can be respectively referred to Figure 2 and Figure 3 for the corresponding intake port 104 and exhaust port 106; compared with Figure 2 and Figure 3 the relative position of the exhaust port 106 in the housing 102, Figure 1 the relative position of the exhaust port shown is different in the housing.
[0025] Refer to Figure 2 and Figure 3 , an embodiment of the present application provides a turbomolecular pump, and the turbomolecular pump 100 includes: a housing 102 provided with an accommodating cavity, including an intake port 104 and an exhaust port 106; a rotating shaft 108 disposed in the accommodating cavity; a first end 1081 of the rotating shaft close to the intake port 104, and a second end 1082 of the rotating shaft close to the exhaust port 106; the extending direction D2 of the exhaust port 106 is parallel to the axial direction D1 of the rotating shaft 108; or, there is a first included angle θ1 between the extending direction D2 of the exhaust port 106 and the axial direction D1 of the rotating shaft; the first included angle θ1 is less than or equal to 30 degrees; a plurality of rotors 110 distributed along the axial direction of the rotating shaft 108; each rotor 110 is distributed circumferentially along the rotating shaft 108; wherein, when the rotating shaft 108 rotates, the rotating shaft 108 drives the plurality of rotors 110 to move together to drive the air flow in the accommodating cavity to flow from the intake port 104 to the exhaust port 106.
[0026] In the embodiments of the present application, there is a first included angle (the first included angle is less than or equal to 30 degrees) between the extending direction of the exhaust port and the axial direction of the rotating shaft, which can be understood as that the included angle between the extending direction of the exhaust port and the air flow direction in the accommodating cavity is small; or, the extending direction of the exhaust port is parallel to the axial direction of the rotating shaft, which can be understood as that the extending direction of the exhaust port is equivalent to the air flow direction in the accommodating cavity. This can greatly improve the exhaust efficiency of the turbo molecular pump, greatly reduce the polymer accumulation rate in the turbo molecular pump, improve the particulate mask defects of the product, increase the overhaul life of the turbo molecular pump while reducing the maintenance cost, and improve the operating time of the turbo molecular pump.
[0027] A plurality of stators 111 are further arranged in the accommodating cavity of the turbo molecular pump 100, axially distributed along the rotating shaft 108 between two adjacent rotors 110; each rotor 110 is circumferentially distributed along the housing 102. Among them, the stator 111 can be arranged on the inner wall of the housing 102. When the rotating shaft 108 rotates, the stator 111 and the housing 102 remain stationary.
[0028] It should be noted that in the drawings of the embodiments of the present application, the gap between the rotor 110 and the stator 111 is not shown. There is a gap and a space between the rotor 110 and the stator 111. When the rotating shaft 108 rotates, the rotor 110 rotates and the stator 111 remains stationary.
[0029] The accommodating cavity of the turbo molecular pump 100 can be communicated with a chamber ( Figure 2 and Figure 3 not shown), for example, the accommodating cavity of the turbo molecular pump 100 is communicated with the chamber through a communication channel.
[0030] The rotating shaft 108 can be arranged at the center of the accommodating cavity. The accommodating cavity is cylindrical, and the rotating shaft 108 is coaxially arranged with the accommodating cavity. When the rotating shaft 108 rotates, the air flow in the accommodating cavity is discharged to the outside of the accommodating cavity (for example, discharged to a purification device outside the etching device), creating a low pressure or negative pressure state in the accommodating cavity, thereby generating an air pressure difference between the chamber and the accommodating cavity, driving the gas in the chamber to flow into the accommodating cavity, and driving the air flow in the accommodating cavity to flow from the intake port 104 to the exhaust port 106, thereby extracting the substances in the chamber.
[0031] The rotor 110 and the stator 111 are arranged staggeredly. For example, each rotor 110 includes a plurality of rotor blades circumferentially arranged and spaced apart, and each stator 111 includes a plurality of stator blades circumferentially arranged and spaced apart. The inclination direction of the rotor blades is staggered (for example, perpendicular) with the inclination direction of the stator blades, and while driving the air flow in the accommodating cavity, the polymer carried in the air flow is driven from the intake port 104 to the exhaust port 106. At the same time, it is avoided that interference occurs between the stator 111 and the rotor 110 during the rotation of the stator 111 with the rotating shaft 108.
[0032] Reference Figure 4 、 Figure 5 and Figure 6 In some embodiments, the turbomolecular pump 100 further includes a gas heating device 112. The gas heating device 112 is connected to the exhaust port 106 along the extension direction D2 of the exhaust port 106, and is configured to heat the air flow flowing into the cavity of the gas heating device 112 from the exhaust port 106, so that the air flow flowing into the cavity of the gas heating device 112 in the gas inflow direction D5 forms a vortex D7, and flows out of the gas heating device 112 in the gas outflow direction D6.
[0033] In the embodiments of the present application, at the bottom of the turbomolecular pump (at the position of the exhaust port 106), the exhaust direction is changed and a gas heating device 112 is added to heat the air flow flowing into the cavity of the gas heating device 112 from the exhaust port 106, and to make the air flow flowing into the cavity of the gas heating device 112 become a vortex D7, changing the air flow direction and magnitude when the polymer P1 is discharged, which helps to improve the accumulation and blockage of the polymer P1 inside the turbomolecular pump, greatly improving the exhaust efficiency of the turbomolecular pump, making the manufacturing process more stable, and increasing the service life of the turbomolecular pump.
[0034] Reference Figure 5 In some embodiments, the gas heating device 112 includes a gas inlet pipe 1121 and a heating channel 1122. The gas inlet direction of the gas inlet pipe 1121 has an angle with the air flow flowing into the cavity of the gas heating device 112 and deviates from the center D3 of the cavity of the gas heating device 112, and is configured to form a vortex D7. The heating channel 1122 is configured to heat the air flow flowing in from the exhaust port 106 and the air flow flowing in from the gas inlet pipe 1121.
[0035] Reference Figure 5 In some embodiments, the gas heating device 112 further includes a temperature sensor 1123, which is configured to detect the gas temperature after the cavity of the gas heating device 112 is heated. The temperature information fed back by the temperature sensor 1123 can be used to feedback and adjust the heating of the cavity gas of the heating device 112 by the heating channel 1122 to control / maintain the gas temperature after the cavity of the heating device 112 is heated.
[0036] Reference Figure 4 and Figure 7 In some embodiments, the turbomolecular pump 100 further includes a rotor cover 114. The rotor cover 114 is disposed in the accommodating cavity and close to the first end 1081, and includes a conical portion 1141. The bottom surface of the conical portion 1141 is close to the first end 1081, and the top end of the conical portion 1141 is far from the first end 1081. The bottom surface of the conical portion 1141 at least covers the first end 1081. Wherein, when the rotating shaft 108 rotates, the rotor cover 114 remains relatively stationary.
[0037] In the embodiments of the present application, during the use of a turbomolecular pump, the rotor cover of the turbomolecular pump has a conical design, including a conical part, which reduces the probability of polymer lifting during the etching process. At the process level, it can reduce the situation where the polymer is likely to lift onto the wafer, resulting in a decrease in yield or even scrapping. For example, it can reduce the particulate mask defects caused by the polymer being likely to lift and fall onto the wafer surface during the high-low pressure conversion process of the etching process; at the equipment level, it will cause the overhaul life of the turbomolecular pump to become shorter, affecting the operation time of the etching machine.
[0038] Reference Figure 4 And Figure 6 Referring to
[0039] In some embodiments, there is a second included angle θ2 between the bottom surface and the side surface of the conical part 1141; the range of the second included angle θ2 is 15 degrees to 75 degrees. Preferably, the second included angle θ2 can be 20 degrees, 25 degrees, 30 degrees or 35 degrees.
[0040] Reference Figure 4 And Figure 6 Referring to
[0041] Reference Figure 7 (a), Figure 7 (b), in some embodiments, the rotor cover 114 further includes a cylindrical part 1142; the cylindrical part 1142 is obtained by extending the bottom surface of the conical part 1141 downward; the downward extension includes vertical / oblique extension; the bottom surface of the cylindrical part 1142 is close to the first end 1081, and the top surface of the cylindrical part 1142 coincides with the bottom surface of the conical part 1141; the conical part 1141 is located on the cylindrical part 1142, and the top end of the conical part 1141 is far from the first end 1081; wherein, the dimension of the cylindrical part 1142 in the vertical direction is less than or equal to 1 / 2 of the dimension of the conical part 1141 in the vertical direction. Referring to Figure 7 (a), the cylindrical part 1142 can be designed to facilitate the disassembly of the rotor cover 114 structure. For example, the cylindrical part 1142 is a prism, which is convenient for using a wrench to disassemble the rotor cover 114. Here, the vertical direction can be understood as the direction parallel to the axis D1 of the rotating shaft, and the oblique direction can be understood as the direction having a third included angle θ3 with the direction perpendicular to the axis D1 of the rotating shaft, where the third included angle θ3 is greater than the second included angle θ2.
[0042] Reference Figure 2 And Figure 3, in some embodiments, the turbomolecular pump 100 further includes a gas supplement port 116; the gas supplement port 116 is connected to the accommodation chamber and is used to supplement the gas in the accommodation chamber to meet the air pressure working conditions of the turbomolecular pump. For example, the accommodation chamber of the turbomolecular pump 100 is communicated with the chamber through a communication channel. When the air pressure in the chamber is lower than a preset value, the gas that can be evacuated from the accommodation chamber of the turbomolecular pump 100 decreases, which is not conducive to the long life of the turbomolecular pump and affects the long-term operation time of the turbomolecular pump. At this time, without affecting the vacuum degree of the chamber, a certain flow rate of gas (such as pure nitrogen) is supplemented through the gas supplement port 116, which can ensure the long-term operation time of the turbomolecular pump and improve the life of the turbomolecular pump.
[0043] Reference Figure 2 and Figure 3 , in some embodiments, the turbomolecular pump 100 further includes a driving unit 118; the driving unit 118 is connected to the rotating shaft 108 and is used to drive the rotating shaft 108 to rotate; the driving unit 118 is close to the second end 1082. The driving unit 118 can be set as an electronic driving unit, and the electronic driving unit can automatically control the rotation speed, power, etc. of the turbomolecular pump 100.
[0044] Reference Figure 2 and Figure 3 , in some embodiments, the turbomolecular pump 100 further includes an opening and closing device 120. The opening and closing device 120 is arranged on the side of the housing close to the chamber, and the turbomolecular pump is communicated with the chamber through a communication channel; the opening and closing of the opening and closing device 120 control the opening and closing of the communication channel; wherein, when the communication channel is controlled to open and the rotating shaft 108 rotates, the rotating shaft drives a plurality of rotors 110 to move together to drive the air flow in the chamber to flow through the communication channel to the accommodation chamber. For example, when the chamber is in the process stage, the opening and closing device is opened to connect the accommodation chamber with the chamber to drive the gas flow in the chamber; when the process in the chamber is completed, the opening and closing device is closed to separate the accommodation chamber from the chamber, and a cleaning gas is introduced into the accommodation chamber to remove impurities. The opening and closing device separates the accommodation chamber from the chamber to prevent impurities from flowing back into the chamber during the cleaning process.
[0045] The above are only the preferred embodiments of the present application, and do not limit the protection scope of the present application. Any equivalent structural transformation made under the concept of the present application by using the content of the specification and drawings of the present application, or directly / indirectly applied in other related technical fields, is included in the protection scope of the present application.
Claims
1. A turbo molecular pump, characterized in that, Comprising: A housing provided with a receiving cavity, including an air inlet port and an air outlet port; A rotating shaft disposed within the receiving cavity; a first end of the rotating shaft is close to the air inlet port, and a second end of the rotating shaft is close to the air outlet port; the extending direction of the air outlet port is parallel to the axial direction of the rotating shaft; or, there is a first included angle between the extending direction of the air outlet port and the axial direction of the rotating shaft; the first included angle is less than or equal to 30 degrees; A plurality of rotors distributed along the axial direction of the rotating shaft; each rotor is distributed circumferentially along the rotating shaft; Wherein, when the rotating shaft rotates, the rotating shaft drives the plurality of rotors to move together to drive the air flow within the receiving cavity to flow from the air inlet port to the air outlet port.
2. The turbo molecular pump according to claim 1, characterized in that, The turbomolecular pump further includes a gas heating device; the gas heating device is connected to the air outlet port along the extending direction of the air outlet port and is used to heat the air flow flowing into the cavity of the gas heating device from the air outlet port, so that the air flow flowing into the cavity of the gas heating device forms a vortex and flows out of the gas heating device.
3. The turbo molecular pump according to claim 2, characterized in that, The gas heating device includes a gas inlet pipe and a heating channel; the gas inlet direction of the gas inlet pipe has an included angle with the air flow flowing into the cavity of the gas heating device and is deviated from the center of the cavity of the gas heating device to form a vortex; the heating channel is used to heat the air flow flowing in from the air outlet port and the air flow flowing in from the gas inlet pipe.
4. The turbo molecular pump according to claim 1, wherein The turbomolecular pump further includes a rotor cover; the rotor cover is disposed within the receiving cavity and close to the first end, including a conical portion; the bottom surface of the conical portion is close to the first end, and the top end of the conical portion is far from the first end; the bottom surface of the conical portion at least covers the first end; wherein, when the rotating shaft rotates, the rotor cover remains stationary.
5. The turbo molecular pump according to claim 4, characterized in that, There is a second included angle between the bottom surface of the conical portion and the side surface of the conical portion; the range of the second included angle is 15 degrees to 75 degrees.
6. The turbo molecular pump according to claim 4, characterized in that, The conical portion includes a cone or a pyramid.
7. The turbo molecular pump according to claim 4, characterized in that The bottom surface of the conical portion covers the first end and a part of the rotor.
8. The turbo molecular pump according to claim 1, characterized in that, The turbomolecular pump further includes a gas supplement port; the gas supplement port is connected to the receiving cavity and is used to supplement the gas in the receiving cavity to meet the air pressure working condition requirements of the turbomolecular pump.
9. The turbo molecular pump according to claim 1, characterized in that, The turbomolecular pump further includes a driving unit; the driving unit is connected to the rotating shaft and is used to drive the rotating shaft to rotate; the driving unit is close to the second end.
10. The turbo molecular pump according to claim 1, characterized in that, The turbomolecular pump further includes an opening and closing device, the opening and closing device is disposed on one side of the housing close to the chamber, and the turbomolecular pump is communicated with the chamber through a communication channel; the opening and closing of the opening and closing device controls the opening and closing of the communication channel; wherein, when the communication channel is opened and the rotating shaft rotates, the rotating shaft drives the plurality of rotors to move together to drive the air flow in the chamber to flow through the communication channel to the receiving cavity.