Liquid supply assembly and liquid supply system

Abstract

The invention discloses a liquid supply assembly and a liquid supply system.The liquid supply assembly comprises a supply pump and a liquid storage device, the liquid storage device comprises a liquid storage cavity and a buffer cavity located beside the bottom of the liquid storage cavity, the buffer cavity communicates with the liquid storage cavity, the height of the buffer cavity is lower than that of the liquid storage cavity, and the volume of the buffer cavity is smaller than that of the liquid storage cavity; the buffer cavity is communicated with the pump liquid inlet channel through the diaphragm valve in an openable and closable manner; a partition wall is arranged between the liquid storage cavity and the buffer cavity, a communicating part is arranged on the partition wall, and liquid in the liquid storage cavity enters the buffer cavity in a bending mode under the action of the communicating part and the partition wall, so that it can be guaranteed that the liquid in the liquid storage cavity smoothly enters the buffer cavity from the bottom, the liquid at the bottom of the liquid storage cavity is fully utilized, and the excellent buffer effect of the buffer cavity can be achieved; and the pressure of liquid on a diaphragm of the diaphragm valve is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, in particular to a liquid supply assembly and a liquid supply system. BACKGROUND

[0002] In the process of using liquid chemicals in semiconductor manufacturing devices, in order to coat a predetermined amount of photoresist solution (photoresist) or other liquid chemicals on a semiconductor wafer each time, a liquid supply system as described in patent No. JP4265820B2 is proposed, in which the liquid supply system is provided with a liquid supply pump that sucks liquid chemicals contained in a liquid chemical tank and coats a predetermined amount of the sucked liquid chemicals on the semiconductor wafer each time. Specifically, the liquid supply pump is a diaphragm pump that has a diaphragm separating a pump chamber for filling liquid chemicals and a working chamber through which a working gas flows, and that deforms the diaphragm toward the pump chamber side by supplying air with a positive pressure to the working chamber through an adjuster, thereby discharging the liquid chemicals. The liquid supply pump is connected to a vacuum source, and the volume of the pump chamber is increased by applying a negative pressure to the liquid supply pump from the vacuum source, thereby sucking the liquid chemicals. With the miniaturization of semiconductor wafers, the influence of micro-bubbles existing in the photoresist on the coating effect is more significant, and the bubbles can cause uneven thickness of the photoresist layer, affecting the quality of exposure and development, and in severe cases, can cause pattern transfer failure or device failure.

[0003] However, in the liquid supply system of the above-mentioned patent, the upstream of the diaphragm pump is the liquid chemical source, and the liquid chemical source is directly connected to the liquid inlet joint of the diaphragm pump through a pipeline and an on-off valve. The liquid chemical source is subjected to a relatively large pressure to push the liquid chemicals to the diaphragm pump. When the diaphragm pump sucks liquid each time, a relatively large suction force is also generated to suck the liquid into the pump chamber. Based on this, the liquid in the liquid chemical source is violently impacted into the pump chamber of the diaphragm pump due to the relatively large pressure. If the collision of the liquid with the relatively large pressure is severe, bubbles can be generated, which seriously affects the subsequent coating and quality of the wafer.

[0004] Therefore, it is still necessary to further improve the liquid supply system to avoid the generation of bubbles due to the violent impact of the liquid when entering the pump chamber. SUMMARY

[0005] In view of the deficiencies in the prior art, the purpose of the present application is to provide a liquid supply assembly and a liquid supply system, which solve the problem of excessive fluctuation of the liquid when entering the pump chamber in the existing liquid supply system.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] A liquid supply assembly, comprising a supply pump, the supply pump comprising a pump chamber with variable volume, a pump liquid inlet channel and a pump liquid outlet channel in communication with the pump chamber; the liquid supply assembly further comprising a liquid reservoir,

[0008] The liquid reservoir comprises a liquid storage cavity, the liquid storage cavity comprises a liquid inlet on the wall of the liquid storage cavity;

[0009] The liquid reservoir further comprises a buffer cavity beside the bottom of the liquid storage cavity, the height of the buffer cavity is lower than the height of the liquid storage cavity, and the volume of the buffer cavity is smaller than the volume of the liquid storage cavity;

[0010] A partition wall is arranged between the liquid storage cavity and the buffer cavity, the partition wall is provided with a communication part, the liquid storage cavity and the buffer cavity are communicated through the communication part, the buffer cavity comprises a liquid outlet on the wall of the buffer cavity, the liquid outlet is openably and closably communicated with the pump liquid inlet channel through a diaphragm valve, and the liquid outlet is located in the horizontal projection range of the partition wall above the communication part.

[0011] The liquid supply assembly of the application is provided with a liquid reservoir upstream of the supply pump, the liquid reservoir comprises a liquid storage cavity and a buffer cavity, the liquid storage cavity is filled with liquid through a liquid inlet, and the liquid storage cavity serves as the first buffer when the entire liquid supply assembly is filled with liquid, while the buffer cavity serves as the second buffer when the liquid supply assembly is filled with liquid; the liquid storage cavity can isolate the liquid disturbance during liquid filling, thereby reducing the pressure change of the pump liquid inlet channel of the supply pump; the buffer cavity is located between the liquid storage cavity and the pump liquid inlet channel, and the liquid level change of the buffer cavity is much gentler and more lagged than that of the liquid storage cavity, so that the stable liquid level provides more constant static pressure for the pump liquid inlet channel, thereby reducing the pressure fluctuation; the height of the buffer cavity is lower than the height of the liquid storage cavity, so as to ensure that basically only liquid enters the buffer cavity, and to avoid that the gas released in the liquid storage cavity enters the pump liquid inlet channel; meanwhile, the volume of the buffer cavity is smaller than the volume of the liquid storage cavity, liquid flows from the larger liquid storage cavity to the smaller buffer cavity, and then flows to the pump liquid inlet channel, which helps to make the liquid flow more uniform and stable, and to reduce the generation of turbulence and bubbles; in addition, the liquid outlet and the pump liquid inlet channel are openably and closably communicated through a diaphragm valve, and when the liquid supply assembly of the application works, the liquid in the liquid storage cavity is full, and then the supply pump starts to suck liquid, so that the full liquid in the liquid storage cavity has a certain pressure, especially the liquid pressure is greater near the bottom of the liquid storage cavity, and the buffer cavity with small volume separates the liquid storage cavity and the pump liquid inlet channel, on the one hand, the small volume of liquid in the buffer cavity directly acts on the diaphragm of the diaphragm valve, compared with the case that the pump liquid inlet channel is directly communicated with the bottom of the liquid storage cavity, the force of the liquid on the diaphragm of the diaphragm valve can be reduced, so as to avoid affecting the deformation of the diaphragm and then affecting the opening and closing function of the diaphragm valve; on the other hand, the liquid suction amount of the supply pump is controlled by changing the volume of the pump chamber through negative pressure, and when the liquid supply assembly works, the diaphragm valve is in an open state, so that the buffer cavity can avoid that the greater liquid pressure in the liquid storage cavity directly impacts into the pump chamber, and avoid that bubbles are generated due to the violent fluctuation of liquid during the liquid filling process.

[0012] The separation wall is arranged between the liquid storage cavity and the buffer cavity, and the communication part is arranged on the separation wall, and the liquid outlet is located in the horizontal projection range of the separation wall above the communication part, so that the liquid outlet is located in the obliquely upper position of the communication part, so that the liquid has a bending flow path, and the liquid needs to flow downward through the communication part and then enter the buffer cavity to rise to the liquid outlet; in this process, the bubble density is much smaller than that of the liquid, and has a strong upward trend, when the liquid flows downward, the bubbles entrained therein resist the downward flow, which makes it more difficult for the bubbles to be "dragged" into the buffer cavity, so as to avoid the gas from being brought into the pump chamber; and after the liquid enters the buffer cavity, it flows upward, which helps to make the liquid flowing into the pump inlet channel more stable, reduces turbulence, and provides more uniform inflow for the supply pump; at the same time, the separation wall physically separates most of the two cavities, so that the liquid level of the buffer cavity is mainly affected by the suction rate of the supply pump, greatly reducing the disturbance of the fluctuation of the liquid entering the storage cavity to the buffer cavity.

[0013] In this way, the liquid in the liquid storage cavity enters the buffer cavity around the bend under the cooperation of the communication part and the separation wall, which can not only ensure that the liquid in the liquid storage cavity smoothly enters the buffer cavity from the bottom and fully utilize the liquid at the bottom of the liquid storage cavity, but also can play the excellent buffering effect of the buffer cavity and reduce the pressure of the liquid on the diaphragm of the diaphragm valve.

[0014] Preferably, the bottom end faces of the liquid storage cavity, the communication part and the buffer cavity are coplanar to reduce the unevenness of the bottom, and the fluctuation of the liquid flowing from the liquid storage cavity to the buffer cavity through the communication part is smaller, and the bubbles are less likely to be released.

[0015] Preferably, the liquid outlet is located on the top side of the buffer cavity, so that the liquid outlet is closer to the top of the liquid storage cavity relative to the communication part and is subjected to smaller hydrostatic pressure; on the other hand, the liquid flows vertically upward from the bottom to the top of the buffer cavity, reducing turbulence and making the flow more stable and orderly, and also reducing the liquid retained in the top of the buffer cavity, so that the liquid entering the buffer cavity can all enter the pump inlet channel through the liquid outlet.

[0016] Preferably, the diaphragm valve comprises an outer ring, an inner ring located on the inner side of the outer ring, and an actuator, the outer ring and the inner ring are arranged radially apart to form a communication cavity, the inner ring forms a valve passage, the actuator is in sealing connection with the outer ring and can seal the inner ring openably and closably; the liquid outlet is located at the end of the valve passage, and the liquid outlet is opened towards the separation wall, and the valve passage is perpendicular to the separation wall on the inner wall surface of the buffer cavity.

[0017] In this way, the diaphragm of the diaphragm valve is sealingly connected with the outer ring and can sealingly open and close the inner ring under the action of the actuator, so as to guide the valve passage and the pump liquid passage; when the liquid in the liquid storage cavity enters the buffer cavity through the communication part by turning 90°, and then the liquid in the buffer cavity enters the valve flow passage by turning 90°, the pressure of the liquid in the buffer cavity on the closed valve diaphragm can be further reduced, and the liquid in the valve passage can be quickly discharged to the pump liquid passage, so that the liquid is prevented from remaining in the valve passage.

[0018] Preferably, the width of the buffer cavity is smaller than the width of the liquid storage cavity, the communication part is located in the middle of the bottom side of the liquid storage cavity, and the two inner side walls of the liquid storage cavity corresponding to the communication part are guide surfaces.

[0019] When setting the height of the buffer cavity, the height of the buffer cavity is preferably appropriately increased to reduce the hydrostatic pressure of the liquid outlet; meanwhile, the volume of the buffer cavity needs to be controlled to avoid the volume of the buffer cavity being too large and losing the effects of flow stabilization and buffering. Therefore, the width of the buffer cavity is smaller than the width of the liquid storage cavity, and the communication part needs to communicate the liquid storage cavity and the buffer cavity. Therefore, the communication part needs to communicate two different widths. The communication part is arranged in the middle of the bottom side of the liquid storage cavity and is provided with guide surfaces, so that the flow path of the liquid can be optimized, the dead zone can be eliminated, the liquid at the bottom of the liquid storage cavity can be collected from both sides to the middle and then flows into the buffer cavity, and the flow deviation can be avoided. Meanwhile, the communication part with the reduced width can inhibit the transmission of fluctuations, so that the liquid level in the buffer cavity is more stable, and the liquid supply is more stable.

[0020] Preferably, the guide surfaces are arc surfaces or inclined surfaces, so that the width of the communication part gradually decreases from the liquid storage cavity to the buffer cavity; the liquid flow direction can be guided, the flow dead zone can be reduced, and the fluctuations of the liquid when passing through the communication part can be avoided, so that the turbulent flow and the generation of bubbles are reduced.

[0021] Preferably, the buffer cavity and the liquid storage cavity are vertically and equidiameterally extended cavities; the buffer cavity is located on the side of the liquid storage cavity and is located in the liquid reservoir, so that the cavities are convenient for forming and structure installation, and the fluid stability in each cavity is also beneficial.

[0022] Preferably, the volume ratio of the buffer cavity to the liquid storage cavity is 0.01-0.05, and the vertical height ratio of the buffer cavity to the liquid storage cavity is 0.1-0.25; so that the liquid in the buffer cavity is always not too much, the diaphragm of the diaphragm valve is not subjected to too much pressure, and the liquid storage cavity does not cause a large liquid pressure on the pump chamber when the diaphragm valve is opened and the pump absorbs liquid, so that the liquid in the buffer cavity can be smoothly absorbed into the pump chamber.

[0023] Preferably, the liquid reservoir comprises a main body and a bottom cover fixedly connected with the main body, the bottom of the main body is an open structure, the bottom cover has a connection with the bottom of the main body, and the bottom of the partition wall is vertically higher than the connection.

[0024] In this way, the bottom cover and the main body are fixed by welding or bonding, and when fixed, the welding liquid or molten liquid is distributed at the bottom opening of the main body, the bottom of the partition wall is higher than the connecting portion, so that the welding liquid or molten liquid is prevented from contacting the bottom of the partition wall and occupying the space of the communication portion after solidification to interfere with the liquid passing through the communication portion.

[0025] In order to achieve the above-mentioned purpose, the application also adopts the following technical solutions:

[0026] A liquid supply system comprises a liquid inlet assembly and a liquid outlet assembly, and further comprises the liquid supply assembly, the liquid inlet assembly is used for supplying liquid to the liquid reservoir, and the liquid outlet assembly is capable of communicating with the pump outlet channel of the supply pump and is used for discharging liquid.

[0027] Based on the liquid supply system, the liquid inlet assembly communicates with the liquid reservoir, the supply pump is improved in liquid inlet by the liquid storage cavity and the buffer cavity, the liquid is prevented from violently fluctuating to generate bubbles in the liquid inlet process, the probability of bubbles entering the pump chamber is reduced, and the coating quality of the wafer is ensured.

[0028] Compared with the prior art, the application has at least the following beneficial effects:

[0029] The liquid supply assembly of the application sets a liquid reservoir upstream of the supply pump, the liquid reservoir comprises a liquid storage cavity and a buffer cavity, the liquid storage cavity is used as the first buffer in the liquid inlet of the entire liquid supply assembly through the liquid inlet port, and the buffer cavity is used as the second buffer in the liquid inlet of the liquid supply assembly; the liquid supply assembly can reduce the diaphragm pressure of the diaphragm valve, avoid affecting the deformation of the diaphragm, and further affect the opening and closing function of the diaphragm valve; the buffer cavity can avoid the liquid pressure in the liquid storage cavity directly impacting the pump chamber, avoid the liquid violently fluctuating to generate bubbles in the liquid inlet process, and greatly weaken the interference of the fluctuation of the liquid storage cavity in the liquid inlet on the pump inlet channel. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0031] Figure 1 It is a structural schematic diagram of the liquid supply assembly of the embodiment of the application;

[0032] Figure 2 It is a sectional structural schematic diagram of the liquid supply assembly of the embodiment of the application;

[0033] Figure 3 Fig. 1 is a structural schematic diagram of a liquid storage and a diaphragm valve according to an embodiment of the present application;

[0034] Figure 4 Fig. 2 is a top view schematic diagram of a liquid storage according to an embodiment of the present application;

[0035] Figure 5 Fig. 3 is a sectional view schematic diagram of A-A in Fig. 1; Figure 4

[0036] Figure 6 Fig. 4 is a sectional view schematic diagram of B-B in Fig. 2; Figure 5

[0037] Fig. 5 is a structural schematic diagram of a liquid supply system according to an embodiment of the present application. Figure 7 BRIEF DESCRIPTION OF DRAWINGS

[0038] 10, supply pump; 11, pump chamber; 12, pump inlet passage; 13, pump outlet passage;

[0039] 20, liquid storage; 21, liquid storage cavity; 211, liquid inlet; 22, buffer cavity; 221, liquid outlet; 23, partition wall; 24, communication part; 241, guide surface; 25, main body; 26, bottom cover; 261, rim; 262, connection part;

[0040] 30, diaphragm valve; 31, outer ring; 32, inner ring; 33, actuator; 34, communication cavity; 35, valve passage; 36, diaphragm;

[0041] 40, liquid inlet assembly; 41, liquid inlet valve group; 42, filter assembly;

[0042] 50, liquid outlet assembly.

[0043] DETAILED DESCRIPTION The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only 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 skilled in the art without creative work fall within the protection scope of the present application.

[0044]

[0045] ​​In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0046] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] As Figure 1 and Figure 2 The liquid supply assembly shown in the drawings comprises a supply pump 10 and a liquid reservoir 20, the supply pump 10 comprising a pump chamber 11 with variable volume, a pump liquid inlet channel 12 communicating with the pump chamber 11, and a pump liquid outlet channel 13, the liquid reservoir 20 being in openable and closable communication with the pump liquid inlet channel 12, the pump chamber 11 changing volume to expand, sucking the liquid in the liquid reservoir 20 into the pump chamber 11 through the pump liquid inlet channel 12, and then the pump chamber 11 changing volume to shrink again, discharging the liquid from the pump chamber 11 through the pump liquid outlet channel 13; the supply pump 10 is provided with a deformable deformation diaphragm, the deformation diaphragm divides the inner cavity of the supply pump 10 into the pump chamber 11 as a liquid cavity and a working chamber as a gas cavity, and the deformation diaphragm deforms when gas is introduced or discharged into the working chamber, thereby changing the volume of the pump chamber 11 to expand or shrink, so that the pump chamber 11 sucks or discharges liquid, the supply pump 10 can adopt an existing diaphragm pump, and its working principle and specific structure will not be described here.

[0048] As Figures 3 to 6As shown, the liquid reservoir 20 of the embodiment includes a liquid storage cavity 21, which includes a liquid inlet 211 on the wall of the liquid storage cavity 21 for liquid inlet; the liquid reservoir 20 further includes a buffer cavity 22 beside the bottom of the liquid storage cavity 21, the height of the buffer cavity 22 is lower than the height of the liquid storage cavity 21, the volume of the buffer cavity 22 is smaller than the volume of the liquid storage cavity 21, and the buffer cavity 22 is in openable and closable communication with the pump liquid inlet channel 12 via the diaphragm valve 30; the buffer cavity 22 includes a liquid outlet 221 on the wall of the buffer cavity 22, which is in openable and closable communication with the pump liquid inlet channel 12 through the diaphragm valve 30, that is, the diaphragm valve 30 has two states of opening and closing, when the diaphragm valve 30 is in the closed state, the liquid outlet 221 is not in communication with the pump liquid inlet channel 12, and when the diaphragm valve 30 is in the open state, the liquid outlet 221 is in communication with the pump liquid inlet channel 12; a vertical partition wall 23 is arranged between the liquid storage cavity 21 and the buffer cavity 22, the partition wall 23 is provided with a communication part 24, the liquid storage cavity 21 and the buffer cavity 22 are communicated through the communication part 24, and the liquid outlet 221 is located in the horizontal projection range of the partition wall 23 above the communication part 24, that is, the partition wall 23 is vertically arranged, and the horizontal projection range represents the height interval between the highest point and the lowest point of the partition wall 23, and the horizontal direction perpendicular to the height interval is projected to form the above-mentioned horizontal projection range, for example, the horizontal direction (left-right direction) is projected to make the projection range of the partition wall 23 cover the liquid outlet 221, that is, the liquid outlet 221 is located obliquely above the communication part 24, the height of the liquid outlet 221 is higher than the highest point of the communication part 24 and not higher than the highest point of the partition wall 23. Figure 5 In the embodiment, the light is projected in the horizontal direction (left-right direction) to make the projection range of the partition wall 23 cover the liquid outlet 221, that is, the liquid outlet 221 is located obliquely above the communication part 24, and the height of the liquid outlet 221 is higher than the highest point of the communication part 24 and not higher than the highest point of the partition wall 23. The communication part 24 is a groove or hole structure for communicating two cavities, and the communication part 24 can be a through hole arranged on the partition wall 23, but not located at the bottom end of the partition wall 23, at this time, there is part of the partition wall 23 above the communication part 24 and part of the partition wall 23 below the communication part 24, and the horizontal projection is projected by the partition wall 23 above the through hole, or the communication part 24 can be an opening structure arranged between the bottom of the partition wall 23 and the bottom wall of the liquid reservoir 20, that is, the bottom end face of the communication part 24 is coplanar with the bottom end faces of the two cavities, at this time, as the opening structure of the communication part 24, there is only the partition wall 23 above, that is, the embodiment shown in the drawings, therefore, the communication part 24 can be arranged in various ways, which are not listed one by one here.

[0049] It should be further pointed out that, in the embodiment, the liquid storage cavity 21 and the buffer cavity 22 are partially co-walled by the partition wall 23, as shown in the drawings. Figure 5As shown, the partition wall 23 is part of the side wall of the liquid storage cavity 21, and the partition wall 23 is the whole side wall of the buffer cavity 22, which is convenient for the manufacture of the liquid storage cavity 21, the buffer cavity 22 and the partition wall 23, and is also conducive to reducing the volume of the liquid reservoir 20. Of course, in other embodiments, the partition wall 23 is not shared between the liquid storage cavity 21 and the buffer cavity 22, and the two opposite side walls of the liquid storage cavity 21 and the buffer cavity 22 are spaced apart, wherein the opposite side walls of the liquid storage cavity 21 and / or the opposite side walls of the buffer cavity 22 constitute the partition wall 23.

[0050] Based on the above structure, the liquid inlet flow path of the liquid is: entering the liquid storage cavity 21 through the liquid inlet 211, the liquid at the bottom of the liquid storage cavity 21 entering the buffer cavity 22 through the communication part 24, until the liquid storage cavity 21 and the buffer cavity 22 are completely filled, and then the diaphragm valve 30 is opened, the buffer cavity 22 is communicated with the pump liquid inlet channel 12, and then the pump 10 is supplied to work, and the liquid is sucked into the pump chamber 11.

[0051] Therefore, the liquid storage cavity 21 is filled through the liquid inlet 211, which is the first buffer when the entire liquid supply assembly is filled with liquid, and the buffer cavity 22 is the second buffer when the liquid supply assembly is filled with liquid. The liquid inlet 211 is located at the upper part of the liquid storage cavity 21, but not at the top of the liquid storage cavity 21, and the distance from the communication part 24 is farther than the distance from the top of the liquid storage cavity 21, so as to avoid the liquid fluctuation during the liquid inlet to interfere with the liquid in the buffer cavity 22; especially in this embodiment, the liquid storage cavity 21 is filled in a full liquid state, that is, a part of the liquid is sucked away by the supply pump 10, and the liquid storage cavity 21 supplements a part of the liquid through the liquid inlet 211, so that the liquid storage cavity 21 and the buffer cavity 22 are always in a full liquid state, avoiding the formation of a cavity in the liquid storage cavity 21, and reducing the generation of liquid fluctuation and bubbles.

[0052] The buffer cavity 22 is located between the liquid storage cavity 21 and the pump liquid inlet channel 12, and the liquid level change is much more gentle and lagging than the liquid storage cavity 21, and the stable liquid level provides a more constant static pressure for the pump liquid inlet channel 12, reducing pressure fluctuation; the height of the buffer cavity 22 is lower than the height of the liquid storage cavity 21, so as to ensure that only liquid enters the buffer cavity 22, avoiding the gas in the gas-liquid separation in the liquid storage cavity 21 entering the pump liquid inlet channel 12; at the same time, the volume of the buffer cavity 22 is smaller than the volume of the liquid storage cavity 21, and the liquid flows from the larger liquid storage cavity 21 to the smaller buffer cavity 22, and then to the pump liquid inlet channel 12, which helps to make the liquid flow more uniform and stable, reducing turbulence and bubble generation.

[0053] The liquid outlet 221 and the pump liquid inlet channel 12 are in openable and closable communication through the diaphragm valve 30, and when the liquid supply assembly of the present application is in operation, the liquid supply pump 10 starts to suck liquid only after the liquid chamber 21 is full of liquid. Therefore, the liquid in the liquid chamber 21 has a certain pressure, especially the liquid closer to the bottom of the liquid chamber 21 has a greater pressure. Through the small-volume buffer chamber 22, the liquid chamber 21 and the pump liquid inlet channel 12 are separated. On the one hand, the small volume of liquid in the buffer chamber 22 acts on the diaphragm of the diaphragm valve 30, which can reduce the force of the liquid pressure on the diaphragm of the diaphragm valve 30 compared with the case that the pump liquid inlet channel 12 is directly connected to the bottom of the liquid chamber 21, thereby avoiding affecting the deformation of the diaphragm and further affecting the opening and closing function of the diaphragm valve 30. On the other hand, the suction amount of the liquid supply pump 10 is controlled by changing the volume of the pump chamber 11 by negative pressure. When the liquid supply assembly is in operation, the diaphragm valve 30 is in an open state, and the buffer chamber 22 can avoid the large liquid pressure in the liquid chamber 21 from directly impacting the pump chamber 11, thereby avoiding the generation of bubbles due to the violent fluctuation of the liquid during the liquid inlet process.

[0054] The arrangement of the partition wall 23 and the communication part 24 and the height of the liquid outlet 221 make the liquid have a bending flow path. The liquid needs to flow downward through the communication part 24 and then enter the buffer chamber 22 to rise to the liquid outlet 221. In this process, the gas bubble has a strong upward trend due to its density being much smaller than that of the liquid. When the liquid flows downward, the gas bubbles entrained therein resist this downward flow, which makes it more difficult for the gas bubbles to be "dragged" into the buffer chamber 22, thereby avoiding the gas from being brought into the pump chamber 11. After the liquid enters the buffer chamber 22, it flows upward, which helps to make the liquid flow into the pump liquid inlet channel 12 more stable, reduces turbulence, and provides more uniform inflow for the liquid supply pump 10. At the same time, the partition wall 23 physically separates most of the areas of the two chambers, so that the liquid level of the buffer chamber 22 is mainly affected by the suction rate of the liquid supply pump 10, greatly reducing the disturbance of the fluctuation of the liquid in the liquid chamber 21 to the buffer chamber 22.

[0055] In this way, the liquid in the liquid chamber 21 is bent into the buffer chamber 22 under the action of the communication part 24 and the partition wall 23, which can not only ensure that the liquid in the liquid chamber 21 flows smoothly from the bottom to the buffer chamber 22 and fully utilize the liquid at the bottom of the liquid chamber 21, but also can play the excellent buffering role of the buffer chamber 22 to reduce the pressure of the liquid on the diaphragm of the diaphragm valve 30.

[0056] Preferably, the volume ratio of the buffer chamber 22 to the liquid chamber 21 is 0.01-0.05, such as Figure 5As shown, the vertical height of the buffer cavity 22 is L1, and the vertical height of the liquid storage cavity 21 is L2, L1:L2 = 0.1-0.25; to ensure that the liquid in the buffer cavity 22 is not too much, and will not cause too much pressure on the diaphragm of the diaphragm valve 30, and will not cause a large liquid pressure on the pump chamber 11 when the diaphragm valve 30 is opened and the liquid is sucked by the supply pump 10, affecting the liquid suction amount, and the liquid in the buffer cavity 22 can be smoothly sucked into the pump chamber 11.

[0057] As shown in the drawings, Figure 5 The bottom of the liquid storage cavity 21, the communication part 24 and the buffer cavity 22 are coplanar to keep the bottom flat. As preferred, the communication part 24 of the embodiment is located between the bottom of the partition wall 23 and the bottom wall of the liquid reservoir 20. When the liquid flows from the liquid storage cavity 21 to the buffer cavity 22 through the communication part 24, the fluctuation is smaller and the bubbles are less likely to be released. Of course, in other embodiments, the bottom of the liquid storage cavity 21, the communication part 24 and the buffer cavity 22 can not be coplanar, and the bottom of the communication part 24 and the buffer cavity 22 can be lower or higher than the liquid storage cavity 21 to guide the liquid to pass through the communication part 24 and enter the buffer cavity 22.

[0058] As preferred, as shown in the drawings, Figure 5 The liquid reservoir 20 includes a main body 25 and a bottom cover 26 fixedly connected with the main body 25. The bottom of the main body 25 is an open structure, and the side of the bottom of the main body 25 has a region protruding to the side, corresponding to the buffer cavity 22. The bottom cover 26 has a rim 261 protruding to the main body 25, and the edge of the bottom cover 26 and the open structure of the bottom of the main body 25 have a connection 262 to form a relatively closed space inside the liquid reservoir 20. The space inside the rim 261 and the space inside the main body 25 together form the liquid storage cavity 21, the communication part 24 and the buffer cavity 22, and the inner surface of the bottom cover 26 is the bottom surface of the liquid storage cavity 21, the communication part 24 and the buffer cavity 22.

[0059] The bottom cover 26 and the main body 25 are fixed by welding or bonding. When fixed, the welding liquid or molten liquid will be distributed at the open structure of the bottom of the main body 25, and the bottom of the partition wall 23 is higher than the connection 262, so as to avoid the welding liquid or molten liquid contacting the bottom of the partition wall 23 and occupying the space of the communication part 24 after solidification to interfere with the liquid passing through the communication part 24. Further, the rim 261 of the bottom cover 26 has an inside-high and outside-low structure, and the open structure of the bottom of the main body 25 has an inside-low and outside-high structure. Thus, when the rim 261 of the bottom cover 26 and the open structure of the bottom of the main body 25 are butted, the inside of the connection 262 abuts and is flush, and the outside of the connection 262 forms a large gap to accommodate more welding liquid or molten liquid, avoiding the excess welding liquid or molten liquid entering the inside of the connection 262 to form a protrusion on the inner wall of the liquid reservoir 20 to interfere with the liquid flow.

[0060] Preferably, the buffer cavity 22 and the liquid storage cavity 21 are vertically and equidiameterally extended cavities; the buffer cavity 22 is located at the side of the liquid storage cavity 21, and both are located in the liquid reservoir 20, that is, the main body 25 inside corresponds to the vertically and equidiameterally extended cavities of most of the buffer cavity 22 and the liquid storage cavity 21. The cavity with such structure has lower processing difficulty, is convenient for cavity formation and structure installation, and is also conducive to maintaining the stability of the fluid in each cavity.

[0061] As shown in Figure 5 , the liquid outlet 221 is located at the top side of the buffer cavity 22. In this way, on the one hand, the liquid outlet 221 is relatively closer to the top of the liquid storage cavity 21 than the communication part 24, and is subjected to smaller hydrostatic pressure; on the other hand, the vertical upward flow of the liquid from the bottom to the top of the buffer cavity 22 can reduce turbulence, make the flow more stable and orderly, also reduce the liquid retained at the top of the buffer cavity 22, and promote the liquid entering the buffer cavity 22 to pass through the liquid outlet 221 and enter the pump liquid inlet channel 12.

[0062] The diaphragm valve 30 includes an outer ring 31, an inner ring 32 located inside the outer ring 31, and an actuator 33. The outer ring 31 and the inner ring 32 are radially spaced apart to form a communication cavity 34. The inner ring 32 forms a valve channel 35. The actuator 33 is sealingly connected with the outer ring 31 and sealingly opens and closes the inner ring 32. Specifically, the diaphragm 36 of the diaphragm valve 30 is sealingly connected with the outer ring 31 and sealingly opens and closes the inner ring 32 under the action of the actuator 33, so as to guide the valve channel 35 and the pump liquid inlet channel 12.

[0063] Preferably, the outer ring 31 and the inner ring 32 are fixedly arranged on the outer wall of the liquid reservoir 20, and can be integrated with the liquid reservoir 20, having high integration degree. The actuator 33 is independent of the liquid reservoir 20. In this way, the diaphragm valve 30 is convenient to disassemble, and the diaphragm 36 and the actuator 33 of the diaphragm valve 30 can be repaired or replaced without disassembling the entire liquid reservoir 20. The structure of the entire diaphragm valve 30 and the liquid reservoir 20 is compact, the flow path of the liquid to the supply pump 10 is short, the fluctuation of the liquid flow is small, and the liquid amount is easy to control.

[0064] The liquid outlet 221 is located at the end of the valve channel 35 and is opened towards the partition wall 23. The valve channel 35 is perpendicular to the partition wall 23 on the inner wall surface of the buffer cavity 22. The buffer cavity 22 and the liquid storage cavity 21 are arranged in parallel. When the liquid in the liquid storage cavity 21 enters the buffer cavity 22 after being bent by 90°, the liquid in the buffer cavity 22 enters the valve channel again after being bent by 90°. This can further reduce the pressure of the liquid in the buffer cavity 22 on the closed valve diaphragm, and also helps the liquid in the valve channel 35 to be quickly discharged to the pump liquid inlet channel 12, avoiding the liquid remaining in the valve channel 35.

[0065] As shown in Figure 6As shown, the connecting part 24 is located in the middle of the bottom side of the liquid storage chamber 21, and the two inner sidewalls of the liquid storage chamber 21 corresponding to the connecting part 24 are both guide surfaces 241. When setting the height of the buffer chamber 22, it is preferable to appropriately increase the height of the buffer chamber 22 to reduce the static pressure of the liquid at the outlet 221. At the same time, it is also necessary to control the volume of the buffer chamber 22 to avoid the buffer chamber 22 becoming too large and losing its flow stabilization and buffering effect. Therefore, the width of the buffer chamber 22 is smaller than the width of the liquid storage chamber 21. The connecting part 24 connects the liquid storage chamber 21 and the buffer chamber 22. Therefore, the connecting part 24 needs to connect two different widths. Setting the connecting part 24 in the middle of the bottom side of the liquid storage chamber 21 and providing the guide surface 241 can optimize the liquid flow path, eliminate dead zones, and allow the liquid at the bottom of the liquid storage chamber 21 to flow into the buffer chamber 22 from both sides to the middle, avoiding flow deviation. At the same time, the narrower connecting part 24 can suppress the transmission of fluctuations, making the liquid level in the buffer chamber 22 more stable and the liquid supply more stable.

[0066] Preferably, the guiding surface 241 is an arc surface or a slope, so that the width of the connecting part 24 gradually decreases from the liquid storage cavity 21 to the buffer cavity 22; this can guide the direction of liquid flow, reduce dead zones, and prevent liquid from undulating when passing through the connecting part 24, thus reducing turbulence and bubble generation; for example Figure 6 As shown, in this embodiment, the guide surface 241 is an arc surface, that is, a rounded corner is provided at the entrance of the connecting part 24 to form the guide surface 241.

[0067] like Figure 7 As shown, the liquid supply system of this embodiment of the invention, in addition to the liquid supply components of the above embodiments, also includes a liquid inlet component 40 and a liquid outlet component 50. The liquid inlet component 40 includes a liquid inlet valve group 41 and a filter component 42. The liquid inlet valve group 41 is connected to the filter component 42, and the filter component 42 is connected to the liquid storage chamber 21 in the liquid storage tank 20 for liquid inlet to the liquid storage tank 20. The liquid outlet component 50 includes a liquid outlet valve, which is closably connected to the pump outlet channel 13 of the supply pump 10 for external liquid outlet. In this embodiment of the liquid supply system, the liquid inlet component 40 is connected to the liquid storage tank 20. The liquid storage chamber 21 and the buffer chamber 22 improve the liquid inlet of the supply pump 10, avoid violent fluctuations in the liquid during the liquid inlet process and generate bubbles, and reduce the probability of bubbles entering the pump chamber 11 to ensure the coating quality of the wafer.

[0068] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A liquid supply assembly, comprising a supply pump (10), said supply pump (10) including a pump chamber (11) with variable volume, a pump inlet channel (12) communicating with said pump chamber (11), and a pump outlet channel (13); characterized in that, The liquid supply assembly also includes a reservoir (20). The liquid reservoir (20) includes a liquid storage chamber (21), and the liquid storage chamber (21) includes a liquid inlet (211) located on the wall of the liquid storage chamber; The reservoir (20) also includes a buffer chamber (22) located beside the bottom of the reservoir (21). The height of the buffer chamber (22) is lower than the height of the reservoir (21), and the volume of the buffer chamber (22) is smaller than the volume of the reservoir (21). A partition wall (23) is provided between the liquid storage chamber (21) and the buffer chamber (22). A connecting part (24) is provided on the partition wall (23). The liquid storage chamber (21) and the buffer chamber (22) are connected through the connecting part (24). The buffer chamber (22) includes an outlet (221) located on the wall of the buffer chamber. The outlet (221) is connected to the pump inlet channel (12) through a diaphragm valve (30). The outlet (221) is located within the horizontal projection range of the partition wall (23) above the connecting part (24).

2. The liquid supply assembly as claimed in claim 1, characterized in that, The bottom surfaces of the liquid storage chamber (21), the connecting part (24), and the buffer chamber (22) are coplanar.

3. The liquid supply assembly as claimed in claim 1, characterized in that, The liquid outlet (221) is located on the top side of the buffer chamber (22).

4. The liquid supply assembly as claimed in claim 1, characterized in that, The diaphragm valve (30) includes an outer ring (31), an inner ring (32) located inside the outer ring (31), and an actuator (33). The outer ring (31) and the inner ring (32) are radially spaced to form a communicating cavity (34). The inner ring (32) forms a valve passage (35). The actuator (33) is sealed to the outer ring (31) and can openably and closeably seal the inner ring (32). The outlet (221) is located at the end of the valve channel (35) and the outlet (221) is opened towards the partition wall (23). The valve channel (35) is perpendicular to the partition wall (23) on the inner wall surface of the buffer cavity (22).

5. The liquid supply assembly as claimed in claim 1, characterized in that, The width of the buffer cavity (22) is smaller than the width of the liquid storage cavity (21). The connecting part (24) is located in the middle of the bottom side of the liquid storage cavity (21). The two inner sidewalls of the liquid storage cavity (21) corresponding to the connecting part (24) are both guide surfaces (241).

6. The liquid supply assembly as claimed in claim 5, characterized in that, The guide surface (241) is an arc surface or a slope, so that the width of the connecting part (24) gradually decreases from the liquid storage cavity (21) to the buffer cavity (22).

7. The liquid supply assembly as claimed in claim 1, characterized in that, Both the buffer cavity (22) and the liquid storage cavity (21) are vertically extending cavities of equal diameter.

8. The liquid supply assembly as claimed in claim 1 or 7, characterized in that, The volume ratio of the buffer chamber (22) to the liquid storage chamber (21) is 0.01-0.05, and the vertical height ratio of the buffer chamber (22) to the liquid storage chamber (21) is 0.1-0.

25.

9. The liquid supply assembly as claimed in claim 2, characterized in that, The liquid reservoir (20) includes a main body (25) and a bottom cover (26) fixedly connected to the main body (25). The bottom of the main body (25) is an open structure. The bottom cover (26) has a connection point (262) with the bottom of the main body (25). The bottom of the partition wall (23) is higher than the connection point (262) in the vertical direction.

10. A liquid supply system, comprising a liquid inlet assembly (40) and a liquid outlet assembly (50), characterized in that, It also includes a liquid supply assembly as described in any one of claims 1 to 9, wherein the liquid inlet assembly (40) is used to supply liquid to the liquid reservoir (20), and the liquid outlet assembly (50) is connected to the pump outlet channel (13) of the supply pump (10) for external liquid discharge.

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