Vacuum assembly with excellent adsorption effect for low-temperature pump

Abstract

The utility model relates to the technical field of vacuum pumps, in particular to a low-temperature pump vacuum assembly with an excellent adsorption effect, which comprises a pump shell, a radiation screen, a baffle assembly and a cold umbrella assembly, gas can be adsorbed or condensed at a low temperature, a required vacuum environment can be quickly realized, a stable vacuum state can be kept, and the machining precision is ensured. Specifically, by arranging the radiation screen, heat energy in the environment can be reflected, heat radiated to the internal cold umbrella assembly is reduced, fluctuation possibly caused by heat radiation to the vacuum environment is reduced, and the stability is good; by arranging the baffle assembly and the cold umbrella assembly and matching with an adsorbent on the baffle assembly and the cold umbrella assembly, gas molecules in the environment can be subjected to multi-stage adsorption or condensation at a low temperature, and efficient adsorption is realized to achieve a required vacuum environment; meanwhile, the baffle assembly is arranged on the outer side of the cold umbrella assembly, heat radiation in the environment can be reflected, the influence of external environment factors on the vacuum degree and the stability of the vacuum degree is reduced, and the stability of the vacuum environment is good.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum pumps, and particularly relates to a vacuum assembly with excellent adsorption effect for a cryopump. Background Art

[0002] A cryopump is a vacuum pump that uses a low-temperature surface to condense gas. It is mainly a vacuum pump that obtains an ultra-high vacuum environment through low-temperature condensation and low-temperature adsorption. It has advantages such as high vacuum degree and clean and oil-free, which has attracted wide attention. It is particularly widely used in the research and production of semiconductors and integrated circuits, as well as in industries such as molecular beam research, vacuum coating equipment, vacuum surface analysis instruments, ion implanters, and space simulation devices. Currently, during the use of a cryopump, as one of the key components, the vacuum assembly is used to adsorb gas molecules in a low-temperature environment to form the required vacuum environment. In the existing vacuum assembly, the effective gas adsorption area is small, that is, the gas reaction time is short, and the adsorption effect is not good, which affects the rapid achievement of the vacuum degree in the cryopump. At the same time, the vacuum environment is easily affected by thermal radiation in the environment and is prone to fluctuations, with poor stability. Therefore, based on the above problems, the existing technology needs to be further improved. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a cryopump with controllable pumping speed and pumping capacity to solve the existing technical problems in the above background art.

[0004] To solve the above technical problems, the technical solution provided by the utility model is: a vacuum assembly with excellent adsorption effect for a cryopump is provided, which includes a pump housing, a radiation shield, a baffle assembly, and a cold shield assembly. The radiation shield is arranged on the inner side wall of the pump housing. The baffle assembly is arranged at the inner top end of the radiation shield. The cold shield assembly is arranged in the radiation shield and below the baffle assembly. Adsorbents are arranged on both the baffle assembly and the cold shield assembly for the adsorption or condensation of gas molecules.

[0005] On the basis of the above technical solution, the shape of the radiation shield is adapted to that of the pump housing.

[0006] On the basis of the above technical solution, the baffle assembly includes a first baffle and a second baffle. The first baffle is fixedly arranged at the inner top end of the radiation shield, and the second baffle is fixedly arranged inside the first baffle.

[0007] On the basis of the above technical solution, the cold shield assembly includes a plurality of cold shield plates uniformly arranged from top to bottom. The cold shield plates are all fixedly connected through mounting frames. Each cold shield plate includes an end plate and a side plate. The side plate is fixedly arranged on the side wall of the end plate and is inclined to the end plate.

[0008] On the basis of the above technical solution, a gap is provided between the outer sidewall of the radiation screen and the inner sidewall of the pump housing, and ventilation holes are provided at the bottom end of the radiation screen.

[0009] On the basis of the above technical solution, the first baffle includes a baffle end plate and baffle blades. The baffle end plate is provided as an annular end plate, and multiple groups of long strip holes are provided on the baffle end plate. One side of the baffle blades is arranged at the bottom end of the long strip holes.

[0010] On the basis of the above technical solution, the second baffle includes a fixing piece and an annular retaining piece. The fixing piece is arranged at the central position of the axis of the radiation screen, the annular retaining piece is arranged outside the fixing piece, and a plurality of annular retaining pieces are provided with diameters increasing sequentially from inside to outside.

[0011] On the basis of the above technical solution, multiple long strip holes are arranged along the diameter direction of the baffle end plate for each group, and the long strip holes are arranged in an arc shape with lengths increasing sequentially.

[0012] On the basis of the above technical solution, the baffle blades are inclined with respect to the baffle end plate.

[0013] On the basis of the above technical solution, the annular retaining piece is inclined with respect to the fixing piece.

[0014] The beneficial effects produced by the technical solution provided by the present utility model are as follows:

[0015] The present utility model provides a vacuum assembly with excellent adsorption effect for a cryogenic pump, which can adsorb or condense gases at low temperature, quickly achieve the required vacuum environment and can maintain a stable vacuum state. In particular, it is suitable for the semiconductor processing process, provides a pure vacuum environment, does not introduce other impurities, and ensures the processing accuracy. Specifically, by providing a radiation screen, the heat energy in the environment can be reflected, reducing the heat radiation to the internal cold shield assembly, reducing the possible fluctuations of the vacuum environment caused by heat radiation, and having good stability; by providing a baffle assembly and a cold shield assembly, cooperating with the adsorbent thereon, the gas molecules in the environment can be multi-stage adsorbed or condensed at low temperature to achieve efficient adsorption to reach the required vacuum environment; at the same time, the baffle assembly is arranged outside the cold shield assembly, and can also reflect the heat radiation in the environment, reducing the influence of external environmental factors on the vacuum degree and its stability, and having good stability of the vacuum environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the overall structural schematic diagram of the present utility model;

[0017] Figure 2 is the internal structural schematic diagram of the present utility model;

[0018] Figure 3It is a schematic structural diagram of the first baffle in the present utility model;

[0019] Figure 4 It is a schematic structural diagram of the second baffle in the present utility model;

[0020] Figure 5 It is a schematic structural diagram of the cold umbrella assembly in the present utility model; Specific embodiments

[0021] The present utility model will be further described below with reference to the accompanying drawings and embodiments:

[0022] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "connection", "connection", "fixation" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be directly connected, or indirectly connected through an intermediate medium. It can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0023] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "left", "right", "front", "rear", "top", "bottom", etc. are all based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model.

[0024] As Figures 1 to 5 shown, a vacuum assembly with excellent adsorption effect for a cryogenic pump includes a pump housing 1, a radiation shield 2, a baffle assembly 3, and a cold umbrella assembly 4. The radiation shield 2 is arranged on the inner side wall of the pump housing 1. The baffle assembly 3 is arranged at the inner top end of the radiation shield 2. The cold umbrella assembly 4 is arranged in the radiation shield 2 and below the baffle assembly 3. Adsorbents are arranged on both the baffle assembly 3 and the cold umbrella assembly 4 for the adsorption or condensation of gas molecules.

[0025] The present utility model provides a vacuum assembly with excellent adsorption effect for a cryopump, which can adsorb or condense gases at low temperature, quickly achieve the required vacuum environment and maintain a stable vacuum state. It is especially suitable for the semiconductor processing process to provide a pure vacuum environment without introducing other impurities and ensure the processing accuracy. Specifically, by providing a radiation shield 2, the heat energy in the environment can be reflected, reducing the heat radiation to the internal cold shield assembly 4 and reducing the possible fluctuations in the vacuum environment caused by thermal radiation, with good stability; by providing a baffle assembly 3 and a cold shield assembly 4, and cooperating with the adsorbent thereon, the gas molecules in the environment can be multi-stage adsorbed or condensed at low temperature to achieve efficient adsorption to reach the required vacuum environment; at the same time, the baffle assembly 3 is arranged outside the cold shield assembly 4, and can also reflect the thermal radiation in the environment, reducing the influence of external environmental factors on the vacuum degree and its stability, and the stability of the vacuum environment is good. Preferably, the adsorbent is made of activated carbon; at the same time, it can be understood that the adsorbent in this application can be obtained from the prior art, and this application does not involve the improvement of the adsorbent material.

[0026] On the basis of the above technical solution, the shape of the radiation shield 2 is adapted to the shape of the pump housing 1.

[0027] On the basis of the above technical solution, a gap is provided between the outer side wall of the radiation shield 2 and the inner side wall of the pump housing 1, and ventilation holes are provided at the bottom end of the radiation shield 2.

[0028] In a preferred embodiment, a gap is provided between the pump housing 1 and the radiation shield 2 to form an auxiliary gas passage. In this way, when the gas flows, it enters the interior through the cold shield assembly, and the gas can directly enter the cold shield assembly 4. At the same time, part of the gas can also enter the cold shield assembly 4 through the auxiliary gas passage and the through holes. In this way, the gas molecules can be adsorbed and solidified quickly and effectively.

[0029] On the basis of the above technical solution, the baffle assembly 3 includes a first baffle 31 and a second baffle 32. The first baffle 31 is fixedly arranged at the top end of the inner side wall of the radiation shield 2, and the second baffle 32 is fixedly arranged inside the first baffle 31.

[0030] By providing the structure of the first baffle 31 and the second baffle 32 and cooperating with the adsorbent thereon, a first-stage adsorption structure is formed in a low-temperature environment to provide adsorption and a solidification position for gas molecules, achieve the high vacuum degree required in the processing environment, and at the same time can effectively reduce the direct impact of the gas on the internal cold shield assembly 4, play a protective role, and extend the service life of the cold shield assembly 4.

[0031] Based on the above technical solution, the first baffle 31 includes a baffle end plate 311 and baffle vanes 312. The baffle end plate 311 is set as an annular end plate, and a plurality of long strip holes 313 are provided on the baffle end plate 311. One side of the baffle vane 312 is arranged at the bottom end of the long strip hole 313.

[0032] Based on the above technical solution, the baffle vane 312 is inclined between the baffle end plate 311.

[0033] Specifically, the first baffle 31 is provided with a baffle end plate 311 and baffle vanes 312. Adsorbents are provided on both the baffle end plate 311 and the baffle vanes 312 to adsorb and solidify the gas, quickly realizing a vacuum environment. At the same time, a plurality of groups of baffle vanes 312 are arranged corresponding to the long strip holes 313 and are inclined, which can increase the effective adsorption area and also radiate part of the heat, reducing the influence of thermal radiation on the vacuum environment, and having good vacuum stability. A plurality of long strip holes 313 are provided on the first baffle 31 and each group is provided with a plurality of long strip holes 313, which can provide a flow channel for the gas, enabling the gas to enter the cold shield assembly for adsorption and solidification to achieve a vacuum state. In a preferred embodiment, the baffle vane 312 is directly stamped downward from the baffle end plate 311, that is, only one side of the baffle vane 312 is connected to the baffle end plate 311, and the other three sides are separated from the baffle end plate 311 after stamping, forming an inclined state with the baffle end plate 311.

[0034] Based on the above technical solution, a plurality of long strip holes 313 are arranged along the diameter direction of the baffle end plate 311, and the long strip holes 313 are arc-shaped and increase in length in sequence.

[0035] In a preferred embodiment, the long strip holes 313 are set as arc-shaped and the lengths of the multiple long strip holes 313 in each group increase in sequence, which can increase the effective adsorption area of the gas, and also increase the gas flow rate, quickly and efficiently realizing the required vacuum environment, and can also maintain the stability of the vacuum state.

[0036] Based on the above technical solution, the second baffle 32 includes a fixing piece 321 and an annular retaining piece 322. The fixing piece 321 is arranged at the central position of the axis of the radiation screen 2, the annular retaining piece 322 is arranged outside the fixing piece 321, and a plurality of annular retaining pieces 322 are provided and increase in diameter from inside to outside in sequence.

[0037] Based on the above technical solution, the annular retaining piece 322 is inclined with the fixing piece 321.

[0038] By providing a second baffle 32, i.e., a plurality of annular baffles 322 with gradually increasing diameters, the gas adsorption area is large, ensuring a rapid achievement of the vacuum state with a good vacuum effect. More preferably, the annular baffles 322 are all inclined, which can increase the effective adsorption area of the gas. At the same time, the inclined circular baffles 322 can also radiate a part of the heat to maintain the stability of the vacuum environment.

[0039] Based on the above technical solution, the cold shield assembly 4 includes a plurality of cold shield plates 41 uniformly arranged from top to bottom. The cold shield plates 41 are all fixedly connected through mounting brackets 42. The cold shield plates 41 include end plates 411 and side plates 412. The side plates 412 are fixedly arranged on the side walls of the end plates 411 and are inclined with respect to the end plates 411.

[0040] By providing a cold shield assembly 4 inside the radiation screen 2, a second adsorption structure is formed in a low-temperature environment, providing adsorption and solidification sites for most gas molecules and rapidly achieving a high-vacuum environment. Specifically, the cold shield assembly 4 includes a plurality of cold shield plates 41 from top to bottom. Cooperating with the adsorbent thereon, more adsorption and solidification sites are provided for gas molecules, and the required vacuum state can be rapidly achieved. More preferably, the included angle between the side plates 412 and the end plates 411 in the cold shield plates 41 is an obtuse angle. In this way, the side plates 412 can reflect a part of the thermal radiation, reducing the adverse effects of heat on the temperature and vacuum degree and reducing the fluctuation of the vacuum degree. As Figure 5 shown, the cold shield plates 41 are all fixedly arranged on the mounting brackets 42. Except for the topmost cold shield plate, notches are provided on the sides of other cold shield plates, mainly for adapting to the installation of the cylinder part of the refrigeration assembly in the cryopump. And openings are provided at the central positions of other cold shield plates, forming through grooves in the radial direction. The mounting brackets 42 are arranged in the through grooves, facilitating the fixation of the cold shield plates and also promoting the rapid flow of gas and the adsorption and solidification of the molecules contained therein.

[0041] More preferably, a through hole 43 is provided on the topmost cold shield plate, and a plurality of through holes 43 are also provided on the mounting brackets 42. By providing the mounting brackets 42, the fixation and disassembly of a plurality of cold shield plates can be assisted. Cooperating with the through holes 43 provided thereon, the flow of gas is facilitated and the molecules existing in the environment are driven for more comprehensive adsorption, meeting the requirements of a vacuum environment with a high vacuum degree.

[0042] The above shows and describes the basic principles and main features of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments. Therefore, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to include all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

[0043] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A vacuum component with excellent adsorption effect for a cryopump, characterized in that: The invention comprises a pump housing (1), a radiation screen (2), a baffle assembly (3) and a cold umbrella assembly (4), wherein the radiation screen (2) is arranged on the inner side wall of the pump housing (1), the baffle assembly (3) is arranged on the inner top of the radiation screen (2), the cold umbrella assembly (4) is arranged inside the radiation screen (2) and below the baffle assembly (3), and adsorbents are arranged on both the baffle assembly (3) and the cold umbrella assembly (4) for adsorption or condensation of gas molecules; the baffle assembly (3) comprises a first baffle (31) and a second baffle (32), wherein the first baffle (31) is fixedly arranged on the inner side top of the radiation screen (2), and the second baffle (32) is fixedly arranged on the inner side of the first baffle (31).

2. A vacuum component with excellent adsorption effect for a cryopump according to claim 1, characterized in that: The radiation screen (2) is adapted to the shape of the pump housing (1).

3. The vacuum component with excellent adsorption effect for a cryopump according to claim 1, characterized in that: The cold umbrella assembly (4) comprises a plurality of cold umbrella sheets (41) evenly arranged from top to bottom, the cold umbrella sheets (41) are all fixedly connected via a mounting frame (42), the cold umbrella sheets (41) comprise an end plate (411) and a side plate (412), the side plate (412) being fixedly arranged on a side wall of the end plate (411) and being arranged obliquely with respect to the end plate (411).

4. The vacuum component with excellent adsorption effect for a cryopump according to claim 2, characterized in that: A gap is provided between the outer wall of the radiation screen (2) and the inner wall of the pump housing (1), and a ventilation hole is provided at the bottom end of the radiation screen (2).

5. The vacuum component with excellent adsorption effect for a cryopump according to claim 1, characterized in that: The first baffle plate (31) comprises a baffle plate end plate (311) and a baffle plate blade (312); the baffle plate end plate (311) is arranged as a circular ring-shaped end plate; a plurality of groups of long strip holes (313) are arranged on the baffle plate end plate (311); and one side of the baffle plate blade (312) is arranged at the bottom end of the long strip hole (313).

6. The vacuum component with excellent adsorption effect for a cryopump according to claim 1, characterized in that: The second baffle (32) comprises a fixing plate (321) and an annular blocking plate (322), wherein the fixing plate (321) is arranged at the center position of the axis of the radiation screen (2), and the annular blocking plate (322) is arranged outside the fixing plate (321), and a plurality of the annular blocking plates (322) are provided, and the diameters increase sequentially from the inside to the outside.

7. The vacuum component with excellent adsorption effect for a cryopump according to claim 5, characterized in that: Each group of long strip holes (313) is provided with a plurality of holes along the diameter direction of the baffle end plate (311), and the long strip holes (313) are arranged in an arc shape and their lengths increase sequentially.

8. The vacuum component with excellent adsorption effect for a cryopump according to claim 5, characterized in that: The baffle blades (312) are arranged obliquely to the baffle end plate (311).

9. The vacuum component with excellent adsorption effect for a cryopump according to claim 6, characterized in that: The annular blocking piece (322) and the fixing piece (321) are arranged obliquely.

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