CN115929662A

CN115929662A - Turbo-molecular pump and integrated rotor element thereof

Info

Publication number: CN115929662A
Application number: CN202210921514.5A
Authority: CN
Inventors: 徐国勋; 戴伟城
Original assignee: PROSOL CORP
Current assignee: PROSOL CORP
Priority date: 2021-08-05
Filing date: 2022-08-02
Publication date: 2023-04-07
Also published as: TWI793705B; TW202307340A

Abstract

The present invention relates to an integrally formed rotor element comprising a rotor seat and a plurality of rotor blades. The top of the rotor base is not provided with a recess, and a plurality of rotor blades are connected to the rotor base and arranged at intervals. The integrally formed rotor element provided by the invention has no exposed recess on the top of the rotor base, so that the process material accumulation in the semiconductor process can be prevented, and the pollution in a vacuum cavity and the problems of a turbo molecular pump are avoided.

Description

Turbo-molecular pump and integrally formed rotor element thereof

Technical Field

The present invention relates to a vacuum pump and a rotor device thereof, and more particularly to a turbo molecular pump capable of preventing accumulation of process materials and an integrally formed rotor device thereof.

Background

Currently, major semiconductor processes such as ion implantation, furnace, thin film sputtering, plasma etching, chemical mechanical polishing, etc. are performed in a vacuum chamber under high vacuum. Therefore, the vacuum environment of the vacuum chamber is one of the key factors affecting the process yield, and the clean and stable vacuum environment is helpful to improve the process yield. Turbo-molecular pumps are used as the heart of a vacuum system, and generate a high vacuum environment by rotating a rotor at a high speed relative to a stator and discharging gas from a vacuum chamber.

The rotor structure of the existing turbo molecular pump can be divided into an assembled type and an integrally formed type, wherein the integrally formed type rotor is provided with a groove at the top of the rotor for processing, and the groove can also be used as a locking chamber for locking a rotating shaft and a correction part for dynamic balance correction.

However, some semiconductor processes generate fine particles of process reactants, and when the turbo-molecular pump extracts the gas in the vacuum chamber, the fine particles are sucked into the turbo-molecular pump, and the fine particles are easily accumulated in the groove at the top of the rotor and cannot be discharged smoothly. When the pressure in the vacuum chamber changes, the particles accumulated in the grooves may fly with the unstable airflow and return to the vacuum chamber to cause contamination, and may cause some problems or errors in the turbomolecular pump and be forced to be taken out of the vacuum chamber for maintenance.

Some integrally formed rotors have a shield plate to shield the grooves to prevent the grooves from accumulating the process material, but this action causes uncontrollable changes in the dynamic balance of the turbomolecular pump, so that the dynamic balance needs to be adjusted when the shield plate is installed, which is very inconvenient, and the process material will enter the grooves from the gap between the shield plate and the rotor due to the pressure difference between the inside and the outside of the grooves during air extraction.

At present, rotors without grooves on the market are all achieved in an assembling mode, the assembling process and the working procedures are extremely complicated, loss is often caused due to process failure, bolt holes are formed in the surfaces of the rotors without the grooves, and the problem of particle accumulation also exists in the bolt holes.

Disclosure of Invention

Accordingly, the present invention provides a turbomolecular pump capable of preventing accumulation of process materials and an integrally formed rotor element thereof, which can avoid contamination in a vacuum chamber and problems of the turbomolecular pump.

In one aspect of the present invention, an integrally formed rotor element of a turbomolecular pump is provided, comprising:

a rotor base having no recess on a top thereof; and

and the rotor blades are connected to the rotor seat and are arranged at intervals.

In one embodiment, the rotor base includes a first base and a second base, the first base is above the second base, and an upper recess is formed at a lower portion of the first base for connecting with the rotating shaft.

In one embodiment, a plurality of bolt holes are formed in the upper concave portion of the first seat body, so that bolts for fixing the rotating shaft can be locked in the bolt holes to lock the rotating shaft on the rotor seat.

In one embodiment, a convex block is formed in the center of the upper concave part of the first seat body, the top of the rotating shaft is provided with a groove, and the shape of the groove is matched with that of the convex block.

In one embodiment, the top end of the rotor seat is a circular platform, and the surface of the circular platform is not provided with a recess.

In one embodiment, the top end of the rotor seat is highest at the center and gradually decreases toward the outside.

In another aspect of the present invention, there is provided a turbomolecular pump comprising:

the shell is provided with an accommodating space and an air inlet end;

the rotor element is arranged in the accommodating space, is an integrally formed rotor element and comprises a rotor seat and a plurality of rotor blades, the top of the rotor seat is adjacent to the air inlet end and is not provided with a recess, and the plurality of rotor blades are connected to the rotor seat and are arranged at intervals;

a rotating shaft connected to the rotor element;

a plurality of stator blades respectively located between the plurality of rotor blades; and

the base is used for fixing the shell and provided with a bearing mechanism, a driving unit and an air outlet end, the bearing mechanism supports the rotating shaft to rotate, the driving unit drives the rotating shaft to enable the rotating shaft to drive the rotor element to rotate at a high speed, and air extracted from the air inlet end moves towards the air outlet end.

In one embodiment, the rotor base includes a first base and a second base, the first base is above the second base, the plurality of rotor blades are connected to the first base, and an upper recess is formed at a lower portion of the first base for connecting with the rotating shaft.

In one embodiment, a plurality of bolt holes are formed in the upper recess of the first seat body for allowing bolts for fixing the rotating shaft to be locked therein to lock the rotating shaft on the rotor seat, a protrusion is formed at the center of the upper recess of the first seat body, a groove is formed at the top of the rotating shaft, and the shape of the groove is matched with the shape of the protrusion.

In one embodiment, the top of the rotor base is a circular platform, the surface of which is not recessed.

The integrally formed rotor element of the turbomolecular pump provided by the invention can prevent the accumulation of process materials in the semiconductor process because no exposed recess is formed on the top of the rotor seat, thereby avoiding the pollution in the vacuum cavity and the problems of the turbomolecular pump.

Drawings

FIG. 1 is a schematic cross-sectional view of a turbomolecular pump according to one embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of an integrally formed rotor component of a turbomolecular pump according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of an integrated rotor element and a rotating shaft of the turbomolecular pump according to an embodiment of the present invention;

FIG. 4a is a schematic cross-sectional view of an integrally formed rotor element of a turbomolecular pump according to another embodiment of the present invention;

fig. 4b and 4c are schematic cross-sectional views of an integrally formed rotor element of a turbomolecular pump according to another embodiment of the present invention.

Description of the reference numerals:

1. turbo molecular pump

1a casing

1b base

11a accommodating space

11b bearing mechanism

12a air inlet end

12b drive unit

13b air outlet end

100. Rotor element

110. Rotor base

111. First seat

112. Second seat body

113. Upper concave part

114. Bolt hole

116. Bump

117. Bolt

118. Balance structure

119a circular platform

119b conical tip

119c dome tip

120. Rotor blade assembly

121. Rotor blade

200. Rotating shaft

212. Groove

300. Stator blade

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will recognize without departing from the spirit and scope of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, but are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and are not to be construed as limiting the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being permanently connected, detachably connected, or integral; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the second feature or the first and second features may be indirectly contacting each other through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Furthermore, the drawings are not 1:1, and the relative sizes of the various elements in the drawings are drawn for illustration only and not necessarily to true scale.

For the purpose of illustration, the drawings show only the structures associated with embodiments of the invention.

In the semiconductor manufacturing process, the yield loss problem caused by random particle defects exists in many process stages, therefore, the invention provides a turbo molecular pump for vacuumizing a vacuum cavity and an integrated rotor element thereof, which is improved in that the top of the integrated rotor element is not provided with a recess, thereby preventing process materials from accumulating so as to avoid pollution caused by flying back to the vacuum cavity along with unstable air flow.

Referring to fig. 1 and 2, the turbomolecular pump 1 of the present invention includes a casing 1a, a rotor element 100, a rotating shaft 200, a plurality of stator blades 300, and a base 1b.

The housing 1a has an accommodating space 11a and an air inlet 12a, and the air inlet 12a is communicated with the accommodating space 11 a.

The rotor element 100 is an integrally formed rotor element, and is disposed in the accommodating space 11a, and mainly includes a rotor base 110 and a plurality of rotor blade sets 120.

The rotor base 110 includes a first base 111 and a second base 112, wherein the first base 111 is connected to the second base 112 and is disposed above the second base 112. The first base 111 and the second base 112 are integrally formed.

The first base 111 is substantially cylindrical and has a structure with a narrow top and a wide bottom. The top of the first seat 111, adjacent to the air inlet 12a, is a planar structure without any recess, i.e. the top of the first seat 111 does not have any groove or bolt hole. The lower portion of the first seat 111 forms an upper recess 113. The upper recess 113 is centrally formed with a projection 116 extending vertically downward from the top of the upper recess 113. The first base 111 further defines a plurality of bolt holes 114, and the bolt holes 114 extend vertically upward from the top of the upper concave portion 113. In addition, a balance structure 118 is radially disposed on a side surface of the first base 111, and the balance structure 118 is used for allowing the weight to be locked on the rotor element 100, so as to adjust the dynamic balance of the rotor element 100 to meet the specification standard. In other embodiments, the balance structure 118 can be replaced with a recess to adjust the dynamic balance by removing a portion of the mass of the rotor element 100.

The second seat 112 is cylindrical and disposed below the first seat 111, and the second seat 112 has a hollow structure, and an upper end thereof is communicated with the upper recess 113 of the first seat 111.

A plurality of rotor blade groups 120 are connected to the rotor base 110 and also extend in a radial direction. Further, each rotor blade group 120 includes a plurality of rotor blades 121 arranged at intervals, and the inclination angle of the rotor blade 121 on the upper layer is greater than or equal to the inclination angle of the rotor blade 121 on the lower layer. In some embodiments, the number of the rotor blades 121 may be selected from 25 to 56, and the inclination angle of the rotor blades 121 may be adjusted from 13 to 45 degrees according to the level of the rotor blade group 120.

The integrally formed rotor element 100 of the turbomolecular pump according to the present invention, wherein a plurality of rotor blades 121 are formed by extending radially outward from the outer wall of the first housing 111. The plurality of rotor blade sets 120, the first base 111, and the second base 112 are integrally formed. The first seat 111 is cylindrical and the second seat 112 is cylindrical. However, these details are merely illustrative of possible embodiments of the integrally formed rotor element 100 and are not intended to limit the present invention.

Referring to fig. 3, a rotating shaft 200 is shown locked to the rotor element 100 of the turbomolecular pump of the present invention. The top of the shaft 200 has a groove 212 that receives the protrusion 116 of the rotor element 100, and the shape of the groove 212 matches the shape of the protrusion 116 of the rotor element 100. The shaft 200 is locked into the bolt hole 114 by the bolt 117, so as to lock the shaft 200 to the rotor element 100, so that the shaft 200 can drive the entire rotor element 100 to rotate.

With continued reference to FIG. 1, a plurality of stator vanes 300 are respectively radially arranged between the rotor vanes 121; the housing 1a is fixed on the base 1b, the base 1b has a bearing mechanism 11b, a driving unit 12b and an air outlet end 13b, the bearing mechanism 11b supports the rotation of the rotation shaft 200, and the driving unit 12b drives the rotation shaft 200 to rotate, so that the rotation shaft 200 drives the rotor element 100 to rotate at a high speed, and the air extracted from the air inlet end 11a moves to the air outlet end 13 b.

In addition, the first base 111 and the second base 112 are integrally formed, the rotor unit 100 has no through hole or gap, and when the upper recess 113 of the first base 111 and the hollow structure of the second base 112 cover the rotating shaft 200, the bearing mechanism 11b and the driving unit 12b, and the three are located thereunder, the three can be protected, so as to prevent corrosive gas in the manufacturing process from contacting the rotating shaft 200, the bearing mechanism 11b and the driving unit 12b, and further achieve the effect of protecting the rotating shaft 200, the bearing mechanism 11b and the driving unit 12 b.

Referring to fig. 4a, in another embodiment of the integrally formed rotor element 100 of the present invention, the top end of the rotor base 110 is a circular platform 119a, and the surface of the circular platform 119a is a planar structure without any recess formed thereon, i.e. without any groove and bolt hole; the circular platform 119a protrudes (is higher) than the uppermost rotor blade 121, so as to prevent the integrally formed rotor element 100 from scratching the rotor blade 121 when being inverted; the circular platform 119a may be cylindrical or truncated cone (truncated cone).

Referring to fig. 4b and 4c, in another embodiment of the integrally formed rotor element 100 of the present invention, the top end of the rotor base 110 may be highest (convex) at the center and gradually decrease toward the outer side; the top end of the rotor holder 110 is conical to form a conical top end 119b as shown in fig. 4b, or the top end of the rotor holder 110 is dome-shaped to form a dome-shaped top end 119c as shown in fig. 4 c.

The invention makes the turbo molecular pump completely avoid the process material from accumulating in the groove or bolt hole above the rotor element in the practical application of the semiconductor by changing the rotor shape, reduces the risk of the backflow of the product and prevents the pollution to the semiconductor process. In addition, the integrally formed rotor element provided by the invention has no through hole or gap formed on the rotor seat, so that corrosive gas in the manufacturing process can be prevented from corroding the inside of the magnetic suspension bearing.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An integrally formed rotor element for a turbomolecular pump, comprising:

a rotor base having no recess on a top thereof; and

2. The integrally formed rotor element according to claim 1, wherein the rotor base comprises a first base and a second base, the first base is above the second base, and a lower portion of the first base forms an upper recess for connecting with the rotating shaft.

3. The integrally formed rotor element of claim 2, wherein a plurality of bolt holes are formed in said upper recess of said first seat for allowing bolts for fixing said shaft to be locked therein to lock said shaft to said rotor seat.

4. A integrally formed rotor element as claimed in claim 3, wherein a projection is formed in the center of said upper recess of said first seat, and the top of said shaft has a groove having a shape matching the shape of said projection.

5. The integrally formed rotor element of any one of claims 1-4, wherein the top end of the rotor seat is a circular platform, the surface of which is free of depressions.

6. An integrally formed rotor element as claimed in any one of claims 1 to 4, wherein the apex of the rotor seat is highest in the centre and gradually decreases towards the outside.

7. A turbomolecular pump, comprising:

the shell is provided with an accommodating space and an air inlet end;

a rotating shaft connected to the rotor element;

the base supplies the casing is fixed, the base has bearing mechanism, drive unit and gives vent to anger the end, bearing mechanism supports the pivot is rotatory, the drive unit drive the pivot makes the pivot drives rotor element is high-speed rotatory, will the gas of inlet end extraction toward give vent to anger the end and remove.

8. The turbomolecular pump of claim 7, wherein the rotor seat comprises a first seat and a second seat, the first seat is above the second seat, the plurality of rotor blades are connected to the first seat, and an upper recess is formed at a lower portion of the first seat for connecting with the rotating shaft.

9. The turbomolecular pump of claim 8, wherein a plurality of bolt holes are formed in the upper recess of the first seat, and bolts for fixing the shaft can be locked to lock the shaft on the rotor seat, and a protrusion is formed in the center of the upper recess of the first seat, and a groove is formed at the top of the shaft, and the shape of the groove matches the shape of the protrusion.

10. The turbomolecular pump of any of claims 7-9, wherein the top of the rotor seat is a circular platform, the surface of which is not recessed.

11. The turbomolecular pump of any of claims 7 to 9, wherein the top end of the rotor seat is highest at the center and gradually decreases towards the outside.