A molecular pump body heating device

Abstract

The application is suitable for the technical field of semiconductor manufacturing equipment, and provides a molecular pump body heating device, which comprises a heating assembly, a power supply connected with the heating assembly, and a limiting assembly for nesting and limiting the heating assembly, the heating assembly comprises symmetrically arranged first and second heating pipes, the first and second heating pipes are arranged in a semicircular arc structure and are respectively attached to the pump body, and the pump body is heated by the first and second heating pipes. The device solves the problem that the effective heating length of the existing heating element is limited by the wall thickness of the pump body, resulting in the decline of heating uniformity and thermal efficiency, and achieves the effect of heating length not being limited by the wall thickness of the molecular pump, axial uniform heating of the pump body, reduction of heat loss to the outside, and improvement of heating efficiency.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing equipment technology, and more specifically, to a molecular pump body heating device. Background Technology

[0002] Magnetic levitation turbomolecular pumps are core equipment for achieving high-vacuum environments in processes such as semiconductor etching, physical vapor deposition, and chemical vapor deposition. During wafer etching, volatile reaction products need to be continuously evacuated from the chamber by a vacuum system to ensure the smooth progress of the etching process. Byproducts such as polymers and chlorides generated during the etching reaction have a tendency to condense at room temperature. When flowing through the inside of the molecular pump, they come into contact with relatively low-temperature structural surfaces such as the blades, directly undergoing a phase transition and solidifying to form powder or waxy substances that adhere to the inner surface of the pump body. As the deposit thickens, it can disrupt the dynamic balance of the molecular pump rotor, increase the imbalance, or cause blockage of the pumping channel, severely affecting the operational stability and pumping performance of the molecular pump.

[0003] To reduce the deposition of reaction byproducts inside the molecular pump, industrial applications typically employ heating belts or heaters installed around the pump body. This ensures that the products remain in a gaseous state throughout their flow through the pump and are smoothly extracted, rather than condensing and adhering to the pump blades or flow channel surfaces. Traditional peripheral heating structures for magnetic levitation molecular pumps are mainly divided into two types: coil-type heating belts and insert-type heating rods. Coil-type heating belts resemble an "electric blanket," consisting of resistance wires, an insulating layer, and a metal sheath, and are installed tightly against the outer wall of the pump body during use. Heating rods, on the other hand, use an insert design, requiring a cylindrical heating rod to be inserted into specially designed heat-conducting holes in the pump body to heat the pump.

[0004] However, coil-type heating belts have low thermal efficiency, and some heat is easily lost to the environment. Furthermore, the limited contact area between the heating belt and the pump body's outer wall makes it difficult to ensure uniform adhesion, leading to uneven temperature distribution on the pump body surface and affecting temperature control accuracy. Insert-type heating rods need to be inserted into specially designed heat-conducting holes in the pump body. This structure requires a certain standard in the pump body wall thickness to ensure sufficient depth of the heat-conducting holes to accommodate heating rods of sufficient length and power. When the radial thickness of the pump body is limited, the heating rod length is insufficient, and the power cannot be increased, making it difficult to meet high-power heating requirements. Whether using heating belts or heating rods, the effective heating length of the heating element is limited by the pump body wall thickness or installation space, making it difficult to achieve a sufficiently long heating path within a limited installation space, thus limiting further improvements in heating uniformity and thermal efficiency. Summary of the Invention

[0005] In view of the problem that the effective heating length of the heating element in the existing technology is limited by the thickness of the pump body, which leads to a decrease in heating uniformity and thermal efficiency, the purpose of this invention is to provide a molecular pump body heating device whose heating length is not limited by the wall thickness of the molecular pump, which can uniformly heat the pump body axially while reducing heat loss to the outside and improving heating efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A molecular pump body heating device includes a heating component, a power supply connected to the heating component, and a limiting component for nesting and limiting the heating component. The heating component includes a first heating tube and a second heating tube symmetrically arranged. The first heating tube and the second heating tube are configured as a semi-circular arc structure and are respectively attached to the pump body. The pump body is heated by the first heating tube and the second heating tube surrounding the pump body.

[0007] The present invention is further configured such that: the pump body includes a main body, and the main body is provided with an installation groove, which is formed around the outer wall of the main body.

[0008] The present invention is further configured such that the diameters of the first heating tube and the second heating tube are adapted to the width of the mounting groove, and the first heating tube and the second heating tube can be nested inside the mounting groove so as to fit against the main body wall.

[0009] The present invention is further configured such that: the first heating tube and the second heating tube are respectively connected to lead wires at both ends, and a temperature recovery switch is connected to one end of the first heating tube and the second heating tube through the lead wires.

[0010] The present invention is further configured such that: the temperature recovery switch is connected in series with the first heating tube and the second heating tube respectively; when the temperature is too high, the temperature recovery switch can automatically cut off the circuit between the first heating tube and the second heating tube to achieve overheat protection.

[0011] The present invention is further configured such that: the outer walls of the first heating tube and the second heating tube are both covered with metal sheaths, and the other ends of the first heating tube and the second heating tube are connected to a power source via lead wires.

[0012] The present invention is further configured such that: the limiting component includes a heating tube pressure ring and a protective cover covering the outside of the heating tube pressure ring, the heating tube pressure ring being fitted around and embedded inside the mounting groove.

[0013] The present invention is further configured such that: the side of the heating tube pressure ring near the mounting groove is provided as a fitting part, the cross section of the fitting part is set as an arc, and the fitting part can fit with the first heating tube and the second heating tube, thereby pressing the first heating tube and the second heating tube between the heating tube pressure ring and the mounting groove.

[0014] The present invention is further configured such that: the upper and lower sides of the heating tube pressure ring are provided as embedded parts, and the distance between the two embedded parts is adapted to the width of the mounting groove.

[0015] The present invention is further configured such that: a plurality of fastening holes are provided on the protective cover skin, and fastening bolts pass through the fastening holes to press the protective cover skin tightly, so that the heating tube pressure ring is tightly fitted into the mounting groove.

[0016] The beneficial effects of this invention are: The first and second heating elements, with their semi-circular arc structures, are symmetrically arranged around the pump body for heating. This effectively overcomes the structural constraints of traditional straight-tube heating elements, which are limited by the pump body wall thickness. The overall heating length of the heating elements can extend fully along the circumference of the pump body, providing uniform heating with complete circumferential coverage of the pump body's outer wall, significantly improving heating uniformity and temperature control accuracy. The outer wall of the heating elements forms a large surface contact with the inner wall of the pump body, trapping most of the heat within the pump body wall. This effectively suppresses heat loss through convection and radiation, ensuring efficient heat transfer to the pump body via thermal conduction. This achieves rapid heating while reducing power consumption. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the structure of the molecular pump body heating device of the present invention.

[0019] Figure 2 for Figure 1 The front view shown.

[0020] Figure 3 For along Figure 2 A cross-sectional view showing section line AA.

[0021] Figure 4 for Figure 3 A magnified view of a portion of region B shown.

[0022] Figure 5 for Figure 4 The diagram shows a cross-sectional view of the heating tube pressure ring.

[0023] Figure 6 for Figure 2 The diagram shows the structure of the pump body heating device after the protective cover has been removed.

[0024] Figure 7 for Figure 2 A schematic diagram of the main body shown.

[0025] Figure 8 for Figure 2 The diagram shows the structure of the protective cover skin.

[0026] Figure 9 for Figure 1 The diagram shows the structure of the heating component and the power supply.

[0027] Figure 10 for Figure 9 The top view shown.

[0028] Explanation of reference numerals in the attached drawings: 1. Heating assembly; 11. First heating element; 12. Second heating element; 13. Lead wire; 14. Metal sheath; 15. Temperature recovery switch; 2. Power supply; 21. Power plug; 22. Power cord; 23. Current fuse; 24. Heat shrink tubing; 3. Grounding wire; 31. Grounding terminal; 32. Conductor; 33. Connector; 4. Limiting component; 41. Heating tube pressure ring; 411. Fitting part; 412. Embedding part; 42. Protective cover skin; 421. Fastening hole; 422. Fastening bolt; 423. Wire hole; 5. Pump body; 51. Mounting ring; 52. Main body; 53. Mounting groove. Detailed Implementation

[0029] To make the technical problem to be solved, the technical solution, and the beneficial effects of this invention clearer, the invention will now be described in detail with reference to the accompanying drawings. This drawing is a simplified schematic diagram, illustrating only the basic aspects of the invention, and therefore only shows the components relevant to the invention. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0030] Please refer to Figure 1-4 A molecular pump body heating device includes a heating component 1, a power supply 2 connected to the heating component 1, and a limiting component 4 for nesting and limiting the heating component 1. The heating component 1 is pressed tightly against the outer wall of the pump body 5 by the limiting component 4. After the power supply 2 is connected and powered on, the heating component 1 heats up, and the heat generated is efficiently transferred to the pump body 5 through direct contact, thereby achieving the heating of the pump body 5.

[0031] Please refer to Figure 1-4 and Figure 7The pump body 5 includes a mounting ring 51 and a main body 52. ​​Both the mounting ring 51 and the main body 52 are hollow cylindrical structures, and are connected by bolts. Correspondingly, the mounting ring 51 and the main body 52 have fitting grooves and rings to ensure good overall sealing of the pump body 5 after connection. The main body 52 has a mounting groove 53, which surrounds the outer wall of the main body 52. ​​The depth of the mounting groove 53 is less than the wall thickness of the main body 52. ​​The depth of the mounting groove 53 can be adaptively adjusted according to the specific model, wall thickness, and heating power requirements of the main body 52, as long as it ensures that the main body 52 still has sufficient structural strength after slotting to meet the normal use requirements of the pump body 5. This application does not impose specific limitations in this regard.

[0032] Please refer to Figure 1-4 , Figure 6 and Figure 9-10The heating assembly 1 includes a symmetrically arranged first heating tube 11 and a second heating tube 12. The first and second heating tubes 11 and 12 are configured with a semi-circular arc structure and are respectively attached to the pump body 5. The first and second heating tubes 11 and 12 are arranged around the outer periphery of the pump body 5, forming a complete annular heating unit to heat the pump body 5. The arc radius of the first and second heating tubes 11 and 12 matches the radius of the mounting groove 53, and the diameter of the first and second heating tubes 11 and 12 matches the width of the mounting groove 53, allowing the first and second heating tubes 11 and 12 to be nested inside the mounting groove 53, thus fitting snugly against the wall of the main body 52, minimizing contact thermal resistance and improving heat transfer efficiency. Both the first and second heating tubes 11 and 12 are metal tubular electric heating elements, each consisting of a heating layer and an insulating thermally conductive layer. The heating layer can be composed of a spiral-shaped resistance heating wire, and the insulating thermally conductive layer can be magnesium oxide powder filled between the heating wire and the tube wall. Both the first heating tube 11 and the second heating tube 12 are fitted with metal sheaths 14. The metal sheaths 14 can be made of stainless steel, copper, or titanium, protecting the first and second heating tubes 11 and 12 while improving their corrosion resistance. When current passes through the resistance heating wires inside the first and second heating tubes 11 and 12, electrical energy is converted into heat energy. The heating wires themselves experience a rapid temperature increase, generating heat. The heat generated by the heating layer is transferred to the metal sheaths 14 through the insulating thermally conductive layer. The metal sheaths 14 directly contact the main body 52, ultimately completing the heat transfer. To further enhance heat transfer, heat dissipation fins can be added to the surface of the metal sheaths 14, increasing the contact area with the main body 52 and further improving the heating effect. The first heating tube 11 and the second heating tube 12 are respectively connected to lead wires 13 at both ends. The lead wires 13 are used to connect to external circuits. The connection between the ends of the first heating tube 11 and the second heating tube 12 and the lead wires 13 can be sealed with sealing materials such as silicone or epoxy resin to prevent moisture and contaminants from entering the interior of the first heating tube 11 and the second heating tube 12 and damaging the insulation performance.

[0033] Please refer to Figure 1-4 , Figure 6 and Figure 9-10A temperature recovery switch 15 is connected to one end of the first heating element 11 and the second heating element 12 via a lead wire 13. The temperature recovery switch 15 is connected in series in the circuit between the first heating element 11 and the second heating element 12. When the temperature is too high, the temperature recovery switch 15 automatically cuts off the circuit between the first heating element 11 and the second heating element 12 to achieve overheat protection. The temperature recovery switch 15 consists of a temperature sensing element, a switch assembly, a transmission mechanism, and a manual reset mechanism. When the circuit is normally connected, the temperature sensing element is in its original upward-protruding state. At this time, the switch assembly keeps the circuit normally closed under its own elastic force, the circuit between the first heating element 11 and the second heating element 12 is conductive, and the equipment works normally. When the temperature exceeds the limit, the temperature sensing element undergoes physical deformation, instantly "jumping" downwards. This pushes the transmission mechanism downwards, forcibly disconnecting the switch assembly circuit, and the circuit between the first heating element 11 and the second heating element 12 is quickly cut off, achieving overheat protection. After the fault is cleared and the switch has cooled sufficiently, the temperature sensing element returns to its initial upward-protruding state, and the circuit is reconnected. It should be noted that the specific structure and selection of the temperature recovery switch 15 are technical means well known to those skilled in the art, and will not be described in detail here.

[0034] Please refer to Figure 1-2 , Figure 6 and Figure 9-10 The other ends of the first heating element 11 and the second heating element 12 are connected to the power supply 2 via lead wires 13. The power supply 2 includes a power plug 21 and a power cord 22. One end of the power cord 22 is connected to the power plug 21, and the other end is connected to the lead wires 13 of the first heating element 11 and the second heating element 12, thus enabling circuit conduction. A heat shrink tube 24 is fitted at the connection between the power cord 22 and the lead wire 13. The heat shrink tube 24 shrinks when heated, tightly covering the connection, providing electrical insulation, sealing against moisture, and mechanical protection. A current fuse 23 is connected in series with the power cord 22. The current fuse 23 is connected in series in the live wire circuit of the power supply, and its function is to provide overcurrent and short-circuit protection for the entire heating circuit. When an abnormal overload or short-circuit current occurs in the circuit, the fuse element inside the current fuse 23 melts quickly, cutting off the circuit, thereby protecting the heating component 1 and the power cord 22 from overcurrent damage. Current flows into the power plug 21, first passing through the current fuse 23 connected in series in the live wire circuit. After being protected by the fuse, the current is transmitted through the power cord 22 to the lead wire 13, then flows sequentially through the first heating element 11, the temperature recovery switch 15, and the second heating element 12, finally returning to the power supply via the neutral wire, forming a complete electrical circuit. It should be noted that the specific structure, model, and parameter selection of the current fuse 23 and the heat shrink tubing 24 are well-known techniques to those skilled in the art and can be selected according to different heating requirements; therefore, this application will not elaborate further.

[0035] Please refer to Figure 6 and Figure 9-10 To prevent accidental electric shock to operators, a grounding wire 3 is installed at the connection between the heating component 1 and the pump body 5. The grounding wire 3 provides a direct path for fault current to return to the power supply, thus preventing electric shock. The grounding wire 3 includes a conductor 32 arranged along the heating component 1 and connectors 33 connected to both ends of the conductor 32. A grounding terminal 31 is connected to the connector 33. One end of the grounding terminal 31 is electrically connected to the metal part of the heating component 1 via the conductor 32, and the other end is securely connected to the grounding electrode of the earth through a grounding system. Because the resistance of the grounding wire 3 is much lower than the resistance of the human body, when a leakage fault occurs in the equipment, the fault current will preferentially flow directly and quickly to the ground through the extremely low impedance conductor 32, bypassing the human body and thus ensuring the personal safety of the operator.

[0036] Please refer to Figure 1-5 and Figure 8 The limiting component 4 includes a heating tube pressure ring 41 and a protective cover 42 covering the heating tube pressure ring 41. The heating tube pressure ring 41 is configured as a circular ring structure with an outer diameter adapted to the outer diameter of the main body 52. ​​After the first heating tube 11 and the second heating tube 12 are nested inside the mounting groove 53, the heating tube pressure ring 41 is fitted around and embedded inside the mounting groove 53, thereby pressing the first heating tube 11 and the second heating tube 12 tightly. Then, the protective cover 42 tightly covers the heating tube pressure ring 41, ensuring that the first heating tube 11 and the second heating tube 12 can fully contact the main body 52 for heat transfer. A fitting part 411 is provided on the side of the heating tube pressure ring 41 near the mounting groove 53. The cross-section of the fitting part 411 is set as an arc shape. The radius of curvature of the arc shape is adapted to the tube diameter of the first heating tube 11 and the second heating tube 12, so that the fitting part 411 can form a tight surface contact with the outer wall of the heating tube, thereby ensuring the pressing effect. Furthermore, the mounting groove 53 near the main body 52 can be designed as an arc shape to ensure that the first heating tube 11 and the second heating tube 12 can fully contact the main body 52. ​​The upper and lower sides of the heating tube pressure ring 41 are provided with embedding parts 412, and the distance between the two embedding parts 412 is adapted to the width of the mounting groove 53, ensuring that the heating tube pressure ring 41 can fully abut against the top and bottom walls of the mounting groove 53, thereby pressing the first heating tube 11 and the second heating tube 12 tightly between the heating tube pressure ring 41 and the mounting groove 53. It should be noted that the heating tube pressure ring 41 can be made of a flexible material with good heat resistance, such as polyimide, which can reduce heat loss to the outside while pressing the first heating tube 11 and the second heating tube 12 tightly.

[0037] Please refer to Figure 1-5 and Figure 8The cover skin 42 has several fastening holes 421. The fastening holes 421 are designed in a waist shape, and each fastening hole 421 allows a corresponding fastening bolt 422 to pass through. After the heating tube pressure ring 41 presses the first heating tube 11 and the second heating tube 12 tightly, the cover skin 42 tightly covers the outside of the heating tube pressure ring 41. Then, the fastening bolts 422 are passed through the fastening holes 421 and locked, thereby pressing and fixing the cover skin 42, ensuring a tight fit between the heating tube pressure ring 41 and the mounting groove 53. To further ensure the reliability of the cover skin 42's coverage, the spacing between the fastening holes 421 and the fastening bolts 422 at the connection points of the cover skin 42 is smaller than at other locations, thereby strengthening the fastening strength at the connection points. Correspondingly, a wire hole 423 is provided on the cover skin 42 at a location corresponding to the power supply 2, facilitating the passage of the power supply line 22 and its connection to the lead wire 13 of the heating assembly 1.

[0038] The heating assembly 1 is pressed and fixed into the mounting groove 53 of the pump body 5 by the limiting component 4, so that the metal sheath tubes 14 of the first heating tube 11 and the second heating tube 12 are tightly fitted to the outer wall of the main body 52. ​​Then, the power plug 21 of the power supply 2 is connected to an external power source. After being protected by the current fuse 23, the current flows sequentially through the resistance heating wire of the first heating tube 11, the temperature recovery switch 15, and the resistance heating wire of the second heating tube 12, forming a complete electrical circuit. After power is applied, the resistance heating wires inside the first heating tube 11 and the second heating tube 12 generate heat, which is transferred to the metal sheath tube 14. The heat is then conducted through the direct contact between the metal sheath tube 14 and the main body 52, heating the pump body 5. During the heating process, if the temperature abnormally rises above a preset threshold, the temperature sensing element of the temperature recovery switch 15 trips, automatically cutting off the circuit to achieve overheat protection. Simultaneously, the current fuse 23, connected in series with the live wire circuit, melts in the event of a short circuit or severe overload, achieving overcurrent protection.

[0039] The first heating element 11 and the second heating element 12, with a semi-circular arc structure, are symmetrically arranged around the outer periphery of the pump body 5 for heating. This effectively overcomes the structural constraints of traditional straight-tube heating elements, which are limited by the pump body wall thickness. The overall heating length of the heating element can be fully extended along the circumference of the pump body 5, providing uniform heating with complete circumferential coverage of the outer wall of the pump body 5, significantly improving heating uniformity and temperature control accuracy. The outer wall of the heating element forms a large surface contact with the inner wall of the pump body 5, trapping most of the heat inside the pump body wall. This effectively suppresses heat loss through convection and radiation, ensuring that heat is efficiently transferred to the pump body 5 via thermal conduction, achieving rapid heating while reducing heating power consumption.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0041] It should be understood that the terms "length", "width", "up", "down", "front and back", "left and right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0042] The above description, based on the preferred embodiments of the present invention, provides guidance. Those skilled in the art can make various changes and modifications without departing from the scope of the invention. The technical scope of this invention is not limited to the contents of the specification but must be determined according to the claims.

Claims

1. A molecular pump body heating device, characterized in that: The device includes a heating component (1), a power supply (2) connected to the heating component (1), and a limiting component (4) for nesting and limiting the heating component (1). The heating component (1) includes a first heating tube (11) and a second heating tube (12) arranged symmetrically. The first heating tube (11) and the second heating tube (12) are set as semi-circular arc structures and are respectively attached to the pump body (5). The pump body (5) is heated by the first heating tube (11) and the second heating tube (12) surrounding it.

2. The molecular pump body heating device according to claim 1, characterized in that: The pump body (5) includes a main body (52), and an installation groove (53) is provided on the main body (52), which is opened around the outer wall of the main body (52).

3. The molecular pump body heating device according to claim 2, characterized in that: The diameters of the first heating tube (11) and the second heating tube (12) are adapted to the width of the mounting groove (53). The first heating tube (11) and the second heating tube (12) can be nested inside the mounting groove (53) so as to fit against the wall of the main body (52).

4. The molecular pump body heating device according to claim 1, characterized in that: The first heating tube (11) and the second heating tube (12) are respectively connected to lead wires (13), and a temperature recovery switch (15) is connected to one end of the first heating tube (11) and the second heating tube (12) through the lead wires (13).

5. The molecular pump body heating device according to claim 4, characterized in that: The temperature recovery switch (15) is connected in series with the first heating tube (11) and the second heating tube (12). When the temperature is too high, the temperature recovery switch (15) can automatically cut off the circuit between the first heating tube (11) and the second heating tube (12) to achieve overheat protection.

6. The molecular pump body heating device according to claim 5, characterized in that: The outer walls of the first heating tube (11) and the second heating tube (12) are both fitted with metal sheath tubes (14), and the other ends of the first heating tube (11) and the second heating tube (12) are connected to the power supply (2) through lead wires (13).

7. The molecular pump body heating device according to claim 2, characterized in that: The limiting component (4) includes a heating tube pressure ring (41) and a protective cover (42) covering the outside of the heating tube pressure ring (41), the heating tube pressure ring (41) being fitted around the inside of the mounting groove (53).

8. A molecular pump body heating device according to claim 7, characterized in that: The heating tube pressure ring (41) is provided with a fitting part (411) on the side near the mounting groove (53). The fitting part (411) has a circular arc cross section. The fitting part (411) can fit with the first heating tube (11) and the second heating tube (12), thereby pressing the first heating tube (11) and the second heating tube (12) between the heating tube pressure ring (41) and the mounting groove (53).

9. A molecular pump body heating device according to claim 8, characterized in that: The heating tube pressure ring (41) is provided with embedded parts (412) on the upper and lower sides, and the distance between the two embedded parts (412) is adapted to the width of the mounting groove (53).

10. A molecular pump body heating device according to claim 9, characterized in that: The cover skin (42) has several fastening holes (421). The fastening bolts (422) pass through the fastening holes (421) to press the cover skin (42) tightly, so that the heating tube pressure ring (41) fits tightly into the mounting groove (53).

Images