Cleaning device

Abstract

The utility model provides a cleaning device which comprises a cleaning cavity, and the cleaning cavity comprises a cavity bottom plate; the supporting table is arranged on the chamber bottom plate and is used for supporting a wafer; the first peripheral wall, the third peripheral wall and the second peripheral wall are arranged on the cavity bottom plate and are sequentially arranged in the direction from the inner side wall of the cleaning cavity to the supporting table, and the first peripheral wall, the third peripheral wall and the second peripheral wall are arranged to be capable of moving in the direction perpendicular to the cavity bottom plate; liquid outlets are formed in the cavity bottom plate between the first peripheral wall and the second peripheral wall, the cavity bottom plate between the first peripheral wall and the third peripheral wall, the cavity bottom plate between the third peripheral wall and the second peripheral wall and the cavity bottom plate between the second peripheral wall and the supporting table. The cleaning device can control the flow direction of the waste liquid in the cleaning process so as to improve the concentration of DSP in the recycled waste liquid.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and particularly to a cleaning device. Background Art

[0002] Semiconductor manufacturing processes can be divided into front-end (FEOL) and back-end (BEOL) processes. In the back-end process, metal wires such as aluminum wires (Al Pad) are required to electrically connect other metal connections in the wafer. During the formation of the metal wires, a dense oxide film and non-ideally grown aluminum will be generated on the surface of the aluminum metal. Therefore, it is necessary to use dilute hydrofluoric acid (DHF) and dilute sulfuric acid / hydrogen peroxide (DSP) to clean the wafer to remove the oxide film and excess aluminum on the surface of the aluminum wires.

[0003] A large amount of DSP is required during the cleaning process of the wafer. If DSP is directly discharged, it will not only pollute the environment but also cause waste of resources.

[0004] Therefore, a cleaning device is needed that can recover DSP during the cleaning process of the wafer. Summary of the Utility Model

[0005] This application provides a cleaning device, including a cleaning chamber, and the cleaning chamber includes: a chamber bottom plate; a support table disposed on the chamber bottom plate for supporting a wafer; a first peripheral wall, a third peripheral wall, and a second peripheral wall disposed on the chamber bottom plate and arranged in sequence along the inner side wall of the cleaning chamber towards the support table, and the first peripheral wall, the third peripheral wall, and the second peripheral wall are respectively configured to be movable in a direction perpendicular to the chamber bottom plate; and drain ports are provided on the chamber bottom plate between the first peripheral wall and the third peripheral wall, on the chamber bottom plate between the third peripheral wall and the second peripheral wall, and on the chamber bottom plate between the second peripheral wall and the support table.

[0006] In some embodiments, the first peripheral wall, the second peripheral wall, and the third peripheral wall respectively include a vertical portion disposed perpendicular to the chamber bottom plate and an inclined portion connecting the end of the vertical portion.

[0007] In some embodiments, the included angle between the vertical portion and the inclined portion of the first peripheral wall is 148 - 152°; the included angle between the vertical portion and the inclined portion of the second peripheral wall is 152 - 156°; and the included angle between the vertical portion and the inclined portion of the third peripheral wall is 150 - 154°.

[0008] In some embodiments, the first peripheral wall can move between a first lower limit position and a first upper limit position in a direction perpendicular to the chamber bottom plate; the second peripheral wall can move between a second lower limit position and a second upper limit position in a direction perpendicular to the chamber bottom plate; the third peripheral wall can move between a third lower limit position and a third upper limit position in a direction perpendicular to the chamber bottom plate; and when the second peripheral wall is at the second lower limit position and the third peripheral wall is at the third lower limit position, the top end of the second peripheral wall abuts against the top end of the third peripheral wall, forming a closed space between the second peripheral wall and the third peripheral wall.

[0009] In some embodiments, when the second peripheral wall is at the second upper limit position and the third peripheral wall is at the third upper limit position, the top end of the second peripheral wall abuts against the top end of the third peripheral wall, forming a closed space between the second peripheral wall and the third peripheral wall.

[0010] In some embodiments, the materials of the first peripheral wall, the second peripheral wall and the third peripheral wall include polytetrafluoroethylene.

[0011] In some embodiments, the support platform is arranged at the center of the chamber bottom plate and includes a support seat and a loading platform connected to the support seat.

[0012] In some embodiments, the support platform further includes a liquid flow channel and a gas flow channel that penetrate through the support seat and the support platform.

[0013] In some embodiments, the cleaning chamber further includes at least four groups of fluid injection components arranged on the circumferential outer side of the first peripheral wall. Any one of the at least four groups of fluid injection components includes a base, a movable nozzle connected to the base, and an injection flow channel that penetrates through the base and the movable nozzle.

[0014] In some embodiments, the at least four groups of fluid injection components include a first fluid injection component, a second fluid injection component, a third fluid injection component, and a fourth fluid injection component. The first fluid injection component is used to inject deionized water onto the second surface of the wafer; the second fluid injection component is used to inject dilute hydrofluoric acid (DHF) onto the second surface of the wafer; the third fluid injection component is used to inject dilute sulfuric acid / hydrogen peroxide (DSP) onto the second surface of the wafer; and the fourth fluid injection component is used to inject dry gas onto the second surface of the wafer.

[0015] The cleaning device provided by the present application includes a first peripheral wall, a third peripheral wall, and a second peripheral wall that are arranged on the bottom plate of the chamber and sequentially along the inner side wall of the cleaning chamber towards the support platform. The first peripheral wall, the third peripheral wall, and the second peripheral wall are respectively configured to be movable in a direction perpendicular to the bottom plate of the chamber, so that the waste liquid generated in different stages during the wafer cleaning process flows into the first drainage chamber, the second drainage chamber, or the third drainage chamber respectively, avoiding the mixing of waste liquid generated in different stages during the wafer cleaning process, thereby increasing the concentration of DSP in the recycled waste liquid. Description of the Drawings

[0016] The following drawings detail the exemplary embodiments disclosed in the present application. Wherein the same reference numerals represent similar structures in several views of the drawings. Those of ordinary skill in the art will understand that these embodiments are non-limiting, exemplary embodiments, and the drawings are only for the purpose of illustration and description, and are not intended to limit the scope of the present application. Embodiments in other ways may also equally achieve the inventive concept in the present application. It should be understood that the drawings are not drawn to scale.

[0017] Among them:

[0018] Figure 1 is a schematic structural diagram of the first state of the prior art cleaning device;

[0019] Figure 2 is a schematic structural diagram of the second state of the prior art cleaning device;

[0020] Figure 3 is a schematic structural diagram of the first state of the angular cleaning device according to some embodiments of the present application;

[0021] Figure 4 is a schematic structural diagram of the second state of the cleaning device according to some embodiments of the present application;

[0022] Figure 5 is a schematic structural diagram of the third state of the cleaning device according to some embodiments of the present application; and

[0023] Figure 6 is a schematic structural diagram of another perspective of the cleaning device according to some embodiments of the present application. Detailed Description of the Specific Embodiments

[0024] The following description provides specific application scenarios and requirements of the present application, aiming to enable those skilled in the art to manufacture and use the content in the present application. For those skilled in the art, various partial modifications to the disclosed embodiments are obvious, and without departing from the spirit and scope of the present application, the general principles defined here can be applied to other embodiments and applications. Therefore, the present application is not limited to the illustrated embodiments, but has the broadest scope consistent with the claims.

[0025] In the Al pad formation process, in order to timely remove the oxides and unnecessary metallic aluminum formed on the surface of the Al pad, it is necessary to perform a cleaning process on the wafer with the Al pad formed on its surface. The cleaning process of the wafer mainly includes: 1) primary deionized water (DIW) cleaning, which is used to remove particulate matter on the wafer surface; 2) dilute hydrofluoric acid (DHF) cleaning, which is used to remove the oxide layer on the Al pad surface; 3) dilute sulfuric acid hydrogen peroxide (DSP) cleaning, which is used to remove the aluminum with unsatisfactory growth on the Al pad surface; 4) secondary deionized water cleaning, which is used to remove the residual DSP and cleaning products on the Al pad surface; and 5) nitrogen drying, which is used to dry the cleaned wafer. Among them, the waste liquid generated in the later stage of the DSP cleaning stage will be recycled. On the one hand, it can reduce environmental pollution, and on the other hand, it can reduce the cleaning cost.

[0026] The cleaning of the wafer is usually carried out in a cleaning chamber. Referring to Figures 1 to 2 , the cleaning chamber includes a chamber bottom plate 10, a support table 20 arranged on the chamber bottom plate 10 for supporting the wafer, a first peripheral wall 31 and a second peripheral wall 32 arranged on the chamber bottom plate 10 and arranged in sequence along the inner side wall of the cleaning chamber towards the support table 20, a first drain port 41 of the chamber bottom plate 10 arranged between the first peripheral wall 31 and the second peripheral wall 32, and a second drain port 42 of the chamber bottom plate 10 arranged between the second peripheral wall 32 and the support table 20.

[0027] When performing primary deionized water cleaning and DHF cleaning on the wafer, the second peripheral wall 32 descends, so that the cleaned waste liquid flows to the gap between the first peripheral wall 31 and the second peripheral wall 32, and flows into the deionized water drain pipeline 51 or the DHF drain pipeline 52 through the first drain port 41.

[0028] When performing DSP cleaning on the wafer, the second peripheral wall 32 ascends, so that the cleaned waste liquid flows to the space between the second peripheral wall 32 and the support table 20, and flows into the DSP drain pipeline 61 or the DSP recovery pipeline 62 through the second drain port 42.

[0029] When performing secondary deionized water cleaning on the wafer, the second peripheral wall 32 ascends and moves to the position during primary deionized water cleaning, so that the cleaned waste liquid flows to the gap between the first peripheral wall 31 and the second peripheral wall 32, and flows into the deionized water drain pipeline 51 through the first drain port 41.

[0030] However, as Figure 1As shown, when the wafer is cleaned with deionized water or DHF for the first time, the waste liquid after cleaning will be splashed back between the second peripheral wall 32 and the support table 20 due to flowing toward the surface of the first peripheral wall 31, thereby reducing the concentration of DSP in the recycled waste liquid during DSP cleaning, and thus affecting the reuse of DSP.

[0031] In order to increase the concentration of DSP in the recycled waste liquid during wafer cleaning, the present application provides a cleaning device, including a cleaning chamber, where the cleaning chamber includes: a chamber bottom plate; a support table disposed on the chamber bottom plate for supporting a wafer; a first peripheral wall, a third peripheral wall, and a second peripheral wall disposed on the chamber bottom plate and arranged in sequence along the inner side wall of the cleaning chamber toward the support table, where the first peripheral wall, the third peripheral wall, and the chamber bottom plate between the first peripheral wall and the third peripheral wall define a first drainage chamber; the second peripheral wall, the third peripheral wall, and the chamber bottom plate between the third peripheral wall and the second peripheral wall define a second drainage chamber; the second peripheral wall, the outer peripheral surface of the support table, and the chamber bottom plate between the second peripheral wall and the support table define a third drainage chamber; the first peripheral wall, the third peripheral wall, and the second peripheral wall are respectively configured to be movable in a direction perpendicular to the chamber bottom plate, so that the waste liquid generated in different stages during the wafer cleaning process flows into the first drainage chamber, the second drainage chamber, or the third drainage chamber respectively, and thus flows to corresponding drain pipes or recovery pipes communicated with the first drainage chamber, the second drainage chamber, or the third drainage chamber, avoiding the mixing of waste liquid generated in different stages during the wafer cleaning process, and thus increasing the concentration of DSP in the recycled waste liquid.

[0032] The technical solution of the present invention will be described in detail below with reference to embodiments and the accompanying drawings.

[0033] Figure 3 It is a schematic structural diagram of the first state of the angle cleaning device according to some embodiments of the present application; Figure 4 It is a schematic structural diagram of the second state of the cleaning device according to some embodiments of the present application; Figure 5 It is a schematic structural diagram of the third state of the cleaning device according to some embodiments of the present application; and Figure 6 It is a schematic structural diagram of another perspective of the cleaning device according to some embodiments of the present application.

[0034] Reference Figures 3 to 5, an embodiment of the present application provides a cleaning device, including a cleaning chamber 100. The cleaning chamber 100 includes a chamber bottom plate 101, a support table 200 disposed on the chamber bottom plate 101 for supporting a wafer, a first peripheral wall 301, a third peripheral wall 303, and a second peripheral wall 302 disposed on the chamber bottom plate 101 and arranged in sequence along the inner side wall of the cleaning chamber 100 towards the support table 200, and a plurality of liquid discharge ports disposed on the chamber bottom plate 101.

[0035] In some embodiments, the cleaning chamber 100 further includes a chamber cover 102, and the chamber cover 102 is covered on the chamber bottom plate 101 to enclose the cleaning chamber 100.

[0036] In some embodiments, the support table 200 is disposed at the center of the chamber bottom plate 101, and includes a support seat 201 and a loading platform 202 disposed above the support seat 201 and connected to the support seat 201. The support seat 201 is connected with a lifting motor and a rotating motor. The lifting motor is used to adjust the movement of the support table 200 in a direction perpendicular to the chamber bottom plate 101, and the rotating motor is used to adjust the rotation of the support table 200 around the axis of the support table 200. A clamping groove for fixing the wafer is disposed on the end face of the loading platform 202 facing the wafer, so as to prevent relative displacement between the wafer and the support table 200 when the support table 200 moves.

[0037] Before placing the wafer into the cleaning chamber 100, the support seat 201 drives the loading platform 202 to rise in a direction perpendicular to the chamber bottom plate 101 to the loading position under the drive of the lifting motor, so as to fix the wafer to the loading platform 202. After the wafer is fixed, the support seat 201 drives the loading platform 202 to descend in a direction perpendicular to the chamber bottom plate 101 to the cleaning position under the drive of the lifting motor. During the process of cleaning the wafer, the support seat 201 drives the loading platform 202 to rotate along the axis of the support table 200 under the drive of the rotating motor. After the cleaning is completed, the support seat 201 drives the loading platform 202 to rise in a direction perpendicular to the chamber bottom plate 101 to the loading position under the drive of the lifting motor, so as to unload the wafer.

[0038] During the cleaning process of the wafer, the cleaning liquid or the waste liquid generated by cleaning may enter the gap between the wafer and the loading platform 202, thereby contaminating the first surface of the wafer. Therefore, it is also necessary to clean and dry the first surface of the wafer. The first surface of the wafer refers to the surface of the wafer facing the loading platform 202.

[0039] In some embodiments, the support platform 200 further includes a liquid flow channel 203 and a gas flow channel 204 that penetrate through the support base 201 and the loading platform 202. The liquid flow channel 203 is used to spray deionized water onto the first surface of the wafer, and the gas flow channel 204 is used to spray drying gas onto the first surface of the wafer to clean and dry the first surface of the wafer. In some embodiments, the port of the liquid flow channel 203 close to the wafer is located at the center of the loading platform 202, so that the deionized water sprayed out by the liquid flow channel 203 can cover the first surface of the wafer by virtue of the centrifugal force generated by the rotation of the loading platform 202.

[0040] In some embodiments, the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303 are coaxially arranged with the support platform 200. The first peripheral wall 301, the third peripheral wall 303, and the chamber bottom plate 101 between the first peripheral wall 301 and the third peripheral wall 303 define a first drainage chamber; the second peripheral wall 302, the third peripheral wall 303, and the chamber bottom plate 101 between the third peripheral wall 303 and the second peripheral wall 302 define a second drainage chamber; the second peripheral wall 302, the outer peripheral surface of the support platform 200, and the chamber bottom plate 101 between the second peripheral wall 302 and the support platform 200 define a third drainage chamber; the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303 are configured to be able to move respectively in a direction perpendicular to the chamber bottom plate 101, so that the waste liquid generated in different stages during the wafer cleaning process flows into the first drainage chamber, the second drainage chamber, or the third drainage chamber respectively, and then flows to the corresponding drain pipe or recovery pipe connected to the first drainage chamber, the second drainage chamber, or the third drainage chamber, avoiding the mixing of waste liquid generated in different stages during the wafer cleaning process.

[0041] In some embodiments, the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303 are connected to a driving mechanism (not shown in the figure) to move respectively in a direction perpendicular to the chamber bottom plate 101 under the drive of the driving mechanism. In some embodiments, the driving structure is disposed on a side of the chamber bottom plate 101 away from the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303, and the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303 pass through the chamber bottom plate 101 and are connected to the driving mechanism.

[0042] In some embodiments, the first peripheral wall 301 can move between a first low limit position and a first high limit position along a direction perpendicular to the chamber bottom plate 101; the second peripheral wall 302 can move between a second low limit position and a second high limit position along a direction perpendicular to the chamber bottom plate 101; and the third peripheral wall 303 can move between a third low limit position and a third high limit position along a direction perpendicular to the chamber bottom plate 101;

[0043] When loading or unloading the wafer, the first peripheral wall 301 is at the first low limit position, the second peripheral wall 302 is at the second low limit position, and the third peripheral wall 303 is at the third low limit position, so that the heights of the top of the first peripheral wall 301, the top of the third peripheral wall 303, and the top of the second peripheral wall 302 in the direction perpendicular to the chamber bottom plate 101 decrease in sequence, and are all lower than the loading position of the loading platform 202.

[0044] Reference Figure 3 , when it is necessary to drain the waste liquid generated by cleaning the wafer to the first drainage cavity, the first peripheral wall 301 is at the first high limit position, the second peripheral wall 302 is at the second low limit position, and the third peripheral wall 303 is at the third low limit position. At this time, the heights of the top of the first peripheral wall 301, the top of the third peripheral wall 303, and the top of the second peripheral wall 302 in the direction perpendicular to the chamber bottom plate 101 decrease in sequence, and the heights of the top of the second peripheral wall 302 and the top of the third peripheral wall 303 in the direction perpendicular to the chamber bottom plate 101 are lower than the cleaning position of the loading platform 202, and the height of the top of the first peripheral wall 301 in the direction perpendicular to the chamber bottom plate 101 is higher than the cleaning position of the loading platform 202. The waste liquid generated by cleaning flows from the surface of the wafer to the first drainage cavity by means of the centrifugal force generated by the rotation of the support table 200.

[0045] Reference Figure 4 , when it is necessary to drain the waste liquid generated by cleaning the wafer to the second drainage cavity, the first peripheral wall 301 is at the first high limit position, the third peripheral wall 303 is at the third high limit position, and the second peripheral wall 302 is at the second low limit position. At this time, the heights of the top of the first peripheral wall 301, the top of the third peripheral wall 303, and the top of the second peripheral wall 302 in the direction perpendicular to the chamber bottom plate 101 decrease in sequence, and the height of the top of the third peripheral wall 303 in the direction perpendicular to the chamber bottom plate 101 is higher than the cleaning position of the loading platform 202, and the height of the top of the second peripheral wall 302 in the direction perpendicular to the chamber bottom plate 101 is lower than the cleaning position of the loading platform 202. The waste liquid generated by cleaning flows from the surface of the wafer to the second flow cavity by means of the centrifugal force generated by the rotation of the support table 200.

[0046] Reference Figure 5 When the waste liquid generated by cleaning the wafer needs to be drained to the third drainage cavity, the first peripheral wall 301 is at the first high limit position, the third peripheral wall 303 is at the third high limit position, and the second peripheral wall 302 is at the second high limit position. At this time, the heights of the top of the first peripheral wall 301, the top of the third peripheral wall 303, and the top of the second peripheral wall 302 in the direction perpendicular to the chamber bottom plate 101 decrease in sequence, and the height of the top of the second peripheral wall 302 in the direction perpendicular to the chamber bottom plate 101 is higher than the cleaning position of the loading platform 202. The waste liquid generated by cleaning flows from the surface of the wafer to the third flow cavity by virtue of the centrifugal force generated by the rotation of the support table 200.

[0047] In some embodiments, when at the first high limit position, the height difference between the top of the first peripheral wall 301 and the cleaning position of the loading platform 202 in the direction perpendicular to the chamber bottom plate 101 is 39 - 40 mm, optionally, the height difference is 39.5 mm; and when at the first low limit position, the height difference between the top of the first peripheral wall 301 and the cleaning position of the loading platform 202 in the direction perpendicular to the chamber bottom plate 101 is 26 - 28 mm, optionally, the height difference is 27 mm.

[0048] In some embodiments, when at the second high limit position, the height difference between the top of the second peripheral wall 302 and the cleaning position of the loading platform 202 in the direction perpendicular to the chamber bottom plate 101 is 34 - 35 mm, optionally, the height difference is 34.8 mm; and when at the second low limit position, the height difference between the top of the second peripheral wall 302 and the cleaning position of the loading platform 202 in the direction perpendicular to the chamber bottom plate 101 is 26 - 28 mm, optionally, the height difference is 27 mm.

[0049] In some embodiments, when at the third high limit position, the height difference between the top of the third peripheral wall 303 and the cleaning position of the loading platform 202 in the direction perpendicular to the chamber bottom plate 101 is 31 - 32 mm, optionally, the height difference is 31.8 mm; and when at the third low limit position, the height difference between the top of the third peripheral wall 303 and the cleaning position of the loading platform 202 in the direction perpendicular to the chamber bottom plate 101 is 26 - 28 mm, optionally, the height difference is 27 mm.

[0050] In some embodiments, the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303 respectively include a vertical portion perpendicular to the chamber bottom plate 101 and an inclined portion connecting the ends of the vertical portions. The inclined portion can be integrally connected to the vertical portion, and the inclined portion is inclined towards the support table 200. The inclined portion can prevent the waste liquid from splashing upwards when touching the first peripheral wall 301, the second peripheral wall 302, or the third peripheral wall 303 and splashing out of the set drainage cavity. At the same time, it can also block the waste liquid splashing downwards from flowing into the drainage cavity adjacent to the set drainage cavity.

[0051] In some embodiments, the first peripheral wall 301 includes a first vertical portion 3011 and a first inclined portion 3012. The included angle between the first inclined portion 3012 and the first vertical portion 3011 is 148° to 152°. Optionally, the included angle is 148°, 150°, or 152°. When the first peripheral wall 301 is at the first low limit position, the height ratio of the first vertical portion 3011 to the first inclined portion 3012 in the direction perpendicular to the chamber bottom plate 101 is 1:(1.8 - 2.2). Optionally, the height ratio is 1:2.0; and when the first peripheral wall 301 is at the first low limit position, the height ratio of the first vertical portion 3011 to the first inclined portion 3012 in the direction perpendicular to the chamber bottom plate 101 is 1:(0.8 - 1.2). Optionally, the height ratio is 1:1.0. Wherein, the height of the first vertical portion 3011 in the direction perpendicular to the chamber bottom plate 101 refers to the height of the first vertical portion 3011 above the chamber bottom plate 101.

[0052] In some embodiments, the second peripheral wall 302 includes a second vertical portion 3021 and a second inclined portion 3022. The included angle between the second inclined portion 3022 and the second vertical portion 3021 is 152° to 156°. Optionally, the included angle is 152°, 154°, or 156°. When the second peripheral wall 302 is at the second low limit position, the height ratio of the second vertical portion 3021 to the second inclined portion 3022 in the direction perpendicular to the chamber bottom plate 101 is 1:(2.8 - 3.2). Optionally, the height ratio is 1:3; and when the second peripheral wall 302 is at the second high limit position, the height ratio of the second vertical portion 3021 to the second inclined portion 3022 in the direction perpendicular to the chamber bottom plate 101 is 1:(1.8 - 2.2). Optionally, the height ratio is 1:2. Wherein, the height of the second vertical portion 3021 in the direction perpendicular to the chamber bottom plate 101 refers to the height of the second vertical portion 3021 above the chamber bottom plate 101.

[0053] In some embodiments, the third peripheral wall 303 includes a third vertical portion 3013 and a third inclined portion 3032. The included angle between the third inclined portion 3032 and the third vertical portion 3013 is 150° to 154°. Optionally, the included angle is 150°, 152° or 154°. When the third peripheral wall 303 is at the third lower limit position, the height ratio of the third vertical portion 3013 to the third inclined portion 3032 in the direction perpendicular to the chamber bottom plate 101 is 1:(3.4 to 3.6). Optionally, the height ratio is 3.5. And when the third peripheral wall 303 is at the third upper limit position, the height ratio of the third vertical portion 3013 to the third inclined portion 3032 in the direction perpendicular to the chamber bottom plate 101 is 1:(2.4 to 2.6). Optionally, the height ratio is 1:2.5. Herein, the height of the third vertical portion 3013 in the direction perpendicular to the chamber bottom plate 101 refers to the height of the third vertical portion 3013 above the chamber bottom plate 101.

[0054] The purpose of adjusting the included angle between the vertical portion and the inclined portion of the first peripheral wall 301, the second peripheral wall 302 and the third peripheral wall 303 and the height ratio of the vertical portion to the inclined portion in the direction perpendicular to the chamber bottom plate 101 is to make the waste liquid generated during the cleaning process flow into the preset drainage chamber more accurately.

[0055] In some embodiments, when the first peripheral wall 301 is at the first upper limit position, the second peripheral wall 302 is at the second lower limit position and the third peripheral wall 303 is at the third lower limit position, the top end of the second peripheral wall 302 abuts against the top end of the third peripheral wall 303, and the second drainage chamber is closed, thereby preventing the waste liquid set to flow to the first drainage chamber from splashing into the second drainage chamber.

[0056] In some embodiments, when the second peripheral wall 302 is at the second upper limit position and the third peripheral wall 303 is at the third upper limit position, the top end of the second peripheral wall 302 abuts against the top end of the third peripheral wall 303, and the second drainage chamber is closed, thereby preventing the waste liquid set to flow to the third drainage chamber from splashing into the second drainage chamber.

[0057] In some embodiments, the materials of the first peripheral wall 301, the second peripheral wall 302 and the third peripheral wall 303 include polytetrafluoroethylene. Polytetrafluoroethylene has excellent corrosion resistance, which can prevent the corrosion of DHF and DSP on the first peripheral wall 301, the second peripheral wall 302, the third peripheral wall 303 and during the cleaning process.

[0058] In some embodiments, the plurality of drain ports include a first drain port 103, a second drain port 104, and a third drain port 105. The first drain port 103 is disposed on the chamber bottom plate 101 between the first peripheral wall 301 and the third peripheral wall 303; the second drain port 104 is disposed on the chamber bottom plate 101 between the third peripheral wall 303 and the second peripheral wall 302; and the third drain port 105 is disposed on the chamber bottom plate 101 between the second peripheral wall 302 and the support platform 200.

[0059] In some embodiments, the first drain port 103 is connected to a DIW drain pipeline 401 and a DHF drain pipeline 402. A first valve body 4011 is disposed on the DIW drain pipeline 401, and a second valve body 4021 is disposed on the DHF drain pipeline 402 to respectively control the on and off states of the DIW drain pipeline 401 and the DHF drain pipeline 402.

[0060] In some embodiments, the third drain port 105 is connected to the DIW drain pipeline 401 and the DHF drain pipeline 402.

[0061] In some embodiments, the first drain port 104 and the third drain port 105 are connected to a main drain pipeline through a first tee pipeline, and the main drain pipeline is respectively connected to the DIW drain pipeline 401 and the DHF drain pipeline 402 through a second tee pipeline.

[0062] In some embodiments, the second drain port 104 is connected to a DSP drain pipeline 501 and a DSP recovery pipeline 502. A third valve body 5011 is disposed on the DSP drain pipeline 501, and a fourth valve body 5021 is disposed on the DSP recovery pipeline 502 to respectively control the on and off states of the DSP drain pipeline 501 and the DSP recovery pipeline 502.

[0063] In some embodiments, the second drain port 10 is connected to the DSP drain pipeline 501 and the DSP recovery pipeline 502 through a third connecting pipeline.

[0064] In some embodiments, the cleaning chamber 100 further includes at least four sets of fluid injection assemblies disposed circumferentially outside the first peripheral wall 301 for injecting liquid or gas onto the second surface of the wafer. Any one of the at least four sets of fluid injection assemblies includes a base, a movable nozzle connected to the base, and an injection channel penetrating through the base and the movable nozzle. In some embodiments, the movable nozzle can move in any direction above the wafer to inject the fluid (liquid or gas) in the injection channel onto and cover the second surface of the wafer. The second surface of the wafer refers to the surface of the wafer away from the loading platform 202.

[0065] Reference Figure 6 , in some embodiments, the at least four sets of fluid injection assemblies include a first fluid injection assembly 601, a second fluid injection assembly 602, a third fluid injection assembly 603, and a fourth fluid injection assembly 604. Among them, the first fluid injection assembly 601 is used to inject deionized water onto the second surface of the wafer; the second fluid injection assembly 602 is used to inject DHF onto the second surface of the wafer; the third fluid injection assembly 603 is used to inject DSP onto the second surface of the wafer; and the fourth fluid injection assembly 604 is used to inject drying gas onto the second surface of the wafer.

[0066] In some embodiments, the drying gas includes inert gases such as nitrogen or argon.

[0067] In some embodiments, the cleaning chamber 100 further includes a closable exhaust hole disposed on the chamber bottom plate 10 below the loading platform 202 for discharging the waste gas generated during the cleaning process.

[0068] In the initial state when the cleaning device provided by the embodiment of the present application is not working, the first peripheral wall 301, the second peripheral wall 302, and the third peripheral wall 303 are respectively disposed at the first low limit position, the second low limit position, and the third low limit position; the loading platform 202 is disposed at the cleaning position; the first valve body 4011, the second valve body 4021, the third valve body 5011, and the fourth valve body 5021 are all in a closed state; and the exhaust hole is in a closed state.

[0069] The cleaning process of the wafer using the cleaning device provided by the embodiment of the present application is as follows:

[0070] 1) Loading the wafer: Raise the loading platform 202 to the loading position to load the wafer. After loading the wafer, lower the loading platform 202 to the cleaning position;

[0071] 2) Primary deionized water cleaning: Drive the loading platform 202 to rotate by the selected rotating motor, open the first valve body 4011, raise the first peripheral wall 301 to the first high limit position, use the first fluid injection assembly 601 to inject deionized water onto the second surface of the wafer, the waste liquid generated after cleaning enters the first drainage cavity, and enters the DIW drainage pipeline 401 through the first drainage port 103. After reaching the first preset time, close the first fluid injection assembly 601 and the first valve body 4011;

[0072] 3) DHF cleaning: Open the second valve body 4012, use the second fluid injection assembly 602 to inject DHF onto the second surface of the wafer, the waste liquid generated after cleaning enters the first drainage cavity, and enters the DHF drainage pipeline 402 through the first drainage port 103. After reaching the second preset time, close the second fluid injection assembly 602 and the second valve body 4021;

[0073] 4) DSP cleaning: Open the third valve body 5011, raise the third peripheral wall 303 to the third high limit position, use the third fluid injection assembly 603 to inject DSP onto the second surface of the wafer, the waste liquid generated after cleaning enters the second drainage cavity, and enters the DSP drainage pipeline 501 through the second drainage port 104. After reaching the third preset time, close the third valve body 5011 and open the fourth valve body 5021 at the same time. The waste liquid generated after cleaning enters the second drainage cavity, and enters the DSP recovery pipeline 502 through the second drainage port 104 to realize the recovery of the waste liquid containing DSP. After reaching the preset fourth time, close the third fluid injection assembly 603 and the fourth valve body 5021;

[0074] In the early stage of DSP cleaning, since there are more impurities other than DSP in the waste liquid and the recovery cost is high, only the waste liquid in the later stage of DSP cleaning is recovered to obtain waste liquid with a higher DSP purity;

[0075] 5) Secondary deionized water cleaning: Open the first valve body 4011, lower the third peripheral wall 303 to the third low limit position, use the first fluid injection assembly 601 to inject deionized water onto the second surface of the wafer, the waste liquid generated after cleaning enters the first drainage cavity, and enters the DIW drainage pipeline 401 through the first drainage port 103. After reaching the fifth preset time, close the first fluid injection assembly 601;

[0076] 6) Cleaning the first side of the wafer: Raise the second peripheral wall 302 and the third peripheral wall 303 to the second high limit position and the third high limit position respectively, introduce deionized water into the liquid flow channel 203 to clean the first side of the wafer. The waste liquid generated after cleaning enters the third drainage cavity and enters the DIW drainage pipeline 401 through the third drainage port 105. After reaching the sixth preset time, stop introducing deionized water into the fluid channel 203 and close the first valve body 4011;

[0077] 7) Drying the wafer: Open the exhaust hole, open the fourth fluid injection assembly 604 to inject nitrogen gas onto the second side of the wafer, and at the same time introduce nitrogen gas into the gas flow channel 204 to inject nitrogen gas onto the first side of the wafer. After reaching the preset seventh time, close the fourth fluid injection assembly 604 and stop introducing nitrogen gas into the gas flow channel 204, and close the exhaust hole;

[0078] 8) Unloading the wafer: Lower the first peripheral wall 301, the second peripheral wall 302 and the third peripheral wall 303 to the first low limit position, the second low limit position and the third low limit position respectively, and raise the loading platform 202 to the loading position to unload the wafer. After unloading is completed, lower the loading platform 202 to the cleaning position.

[0079] The beneficial effects that may be brought by the embodiments of the present application include but are not limited to:

[0080] 1) The cleaning device provided by the present application includes a first peripheral wall, a third peripheral wall and a second peripheral wall which are arranged on the chamber bottom plate and sequentially arranged along the inner side wall of the cleaning chamber towards the support table. The first peripheral wall, the third peripheral wall and the second peripheral wall are respectively arranged to be movable in a direction perpendicular to the chamber bottom plate, so that the waste liquid generated in different stages during the wafer cleaning process flows into the first drainage cavity, the second drainage cavity or the third drainage cavity respectively, avoiding the mixing of waste liquid generated in different stages during the wafer cleaning process, thereby increasing the concentration of DSP in the recycled waste liquid.

[0081] 2) The first peripheral wall, the second peripheral wall and the third peripheral wall respectively include a vertical portion perpendicular to the chamber bottom plate and an inclined portion connecting the ends of the vertical portion. The inclined portion can prevent the waste liquid from splashing upwards when touching the first peripheral wall, the second peripheral wall or the third peripheral wall and splashing out of the set drainage cavity. At the same time, it can also block the waste liquid splashing downwards from flowing to the drainage cavity adjacent to the set drainage cavity.

[0082] 3) When the first peripheral wall is at the first high limit position, the second peripheral wall is at the first low limit position, and the third peripheral wall is at the third low limit position, the top end of the second peripheral wall abuts against the top end of the third peripheral wall, and the second drainage cavity is closed, thereby preventing the waste liquid flowing to the first drainage cavity from splashing into the second drainage cavity. That is, it prevents the waste liquid generated during the deionized water cleaning, DHF cleaning, and secondary deionized water cleaning from entering the drainage cavity for draining the waste liquid during DSP cleaning, thereby increasing the concentration of DSP in the recycled waste liquid.

[0083] In addition, when the second peripheral wall is at the second high limit position and the third peripheral wall is at the third high limit position, the top end of the second peripheral wall abuts against the top end of the third peripheral wall, and the second drainage cavity is closed, thereby preventing the waste liquid flowing to the third drainage cavity from splashing into the second drainage cavity. That is, it prevents the waste liquid generated when cleaning the second surface of the wafer with deionized water from entering the drainage cavity for draining the waste liquid during DSP cleaning, thereby increasing the concentration of DSP in the recycled waste liquid.

[0084] The cleaning device provided in this application controls the flow direction of the waste liquid during the cleaning process by arranging three peripheral walls that move in a direction perpendicular to the bottom plate of the chamber in the cleaning chamber, so as to increase the concentration of DSP in the recycled waste liquid. In addition, by adjusting the bending angle at the top of the three peripheral walls, the top height, and the distance from the peripheral wall to the edge of the support table, the flow direction of the waste liquid is more precisely controlled, further increasing the concentration of DSP in the recycled waste liquid.

[0085] It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the possible beneficial effects may be any one or several combinations of the above, or any other possible beneficial effects that can be obtained.

[0086] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only an example and does not constitute a limitation to this specification. Although not explicitly stated here, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are proposed in this specification, so such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of this application.

[0087] It should be noted that in the description of the present application, unless otherwise clearly specified and defined, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be a rotational connection or a sliding connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside 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 application can be understood in combination with specific situations.

[0088] In addition, when the terms "first", "second", "third", etc. are used in the description of the present application to describe various features, these terms are only used to distinguish these features and cannot be understood as indicating or implying the relevance, relative importance, or implicitly indicating the number of the indicated features.

[0089] In addition, the description of the exemplary embodiments in the present application is made by referring to idealized exemplary cross-sectional views and / or plan views and / or three-dimensional views. Therefore, differences from the shapes shown in the figures due to, for example, manufacturing techniques and / or tolerances are foreseeable. Therefore, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but should include deviations in the shapes caused by, for example, manufacturing. Therefore, the regions shown in the figures are substantially schematic, and their shapes are not for showing the actual shapes of the regions of the device nor for limiting the scope of the exemplary embodiments.

[0090] At the same time, the present application uses specific terms to describe the embodiments of the present specification. Such as "one embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure, or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in the present application does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the present application can be appropriately combined.

[0091] Similarly, it should be noted that in order to simplify the expression of the present application disclosure and thus help the understanding of one or more inventive embodiments, in the previous description of the embodiments of the present application, sometimes multiple features are merged into one embodiment, drawing, or description thereof. However, this disclosure method does not mean that the features required by the object of the present application are more than those mentioned in the claims. In fact, the features of the embodiments are less than all the features of the above-disclosed single embodiment.

[0092] Finally, it should be understood that the embodiments described in this application are only used to illustrate the principles of the embodiments of this application. Other variations may also fall within the scope of this application. Therefore, by way of example and not limitation, alternative configurations of the embodiments of this application may be regarded as consistent with the teachings of this application. Accordingly, the embodiments of this application are not limited to the embodiments explicitly presented and described in this application.

Claims

1. A cleaning device, comprising a cleaning chamber, characterized in that, The cleaning chamber includes: A chamber bottom plate; A support table disposed on the chamber bottom plate for supporting a wafer; A first peripheral wall, a third peripheral wall, and a second peripheral wall disposed on the chamber bottom plate and arranged in sequence along the inner side wall of the cleaning chamber towards the support table, wherein the first peripheral wall, the third peripheral wall, and the second peripheral wall are respectively configured to be movable in a direction perpendicular to the chamber bottom plate; and Drain ports are provided on the chamber bottom plate between the first peripheral wall and the third peripheral wall, on the chamber bottom plate between the third peripheral wall and the second peripheral wall, and on the chamber bottom plate between the second peripheral wall and the support table.

2. The cleaning device according to claim 1, characterized in that, The first peripheral wall, the second peripheral wall, and the third peripheral wall respectively include a vertical portion disposed perpendicular to the chamber bottom plate and an inclined portion connecting the ends of the vertical portion.

3. The cleaning device according to claim 2, characterized in that, The included angle between the vertical portion and the inclined portion of the first peripheral wall is 148 - 152°; the included angle between the vertical portion and the inclined portion of the second peripheral wall is 152 - 156°; and the included angle between the vertical portion and the inclined portion of the third peripheral wall is 150 - 154°.

4. The cleaning device according to claim 3, wherein, The first peripheral wall can move in a direction perpendicular to the chamber bottom plate between a first low limit position and a first high limit position; the second peripheral wall can move in a direction perpendicular to the chamber bottom plate between a second low limit position and a second high limit position; the third peripheral wall can move in a direction perpendicular to the chamber bottom plate between a third low limit position and a third high limit position; and when the second peripheral wall is at the second low limit position and the third peripheral wall is at the third low limit position, the top ends of the second peripheral wall and the third peripheral wall are in contact with each other, forming a closed space between the second peripheral wall and the third peripheral wall.

5. The cleaning device according to claim 4, characterized in that, When the second peripheral wall is at the second high limit position and the third peripheral wall is at the third high limit position, the top ends of the second peripheral wall and the third peripheral wall are in contact with each other, forming a closed space between the second peripheral wall and the third peripheral wall.

6. The cleaning device according to claim 1, wherein The materials of the first peripheral wall, the second peripheral wall, and the third peripheral wall include polytetrafluoroethylene.

7. The cleaning device according to claim 1, wherein, The support table is disposed at the center of the chamber bottom plate and includes a support seat and a loading platform connected to the support seat.

8. The cleaning device according to claim 7, wherein, The support table further includes a liquid flow channel and a gas flow channel penetrating through the support seat and the support table.

9. The cleaning device according to claim 1, wherein The cleaning chamber further includes at least four groups of fluid injection components disposed on the outer circumference of the first peripheral wall. Any one of the at least four groups of fluid injection components includes a base, a movable nozzle connected to the base, and an injection flow channel penetrating through the base and the movable nozzle.

10. The cleaning device according to claim 9, characterized in that, The at least four groups of fluid injection components include a first fluid injection component, a second fluid injection component, a third fluid injection component, and a fourth fluid injection component. The first fluid injection component is used to inject deionized water onto the second surface of the wafer; the second fluid injection component is used to inject dilute hydrofluoric acid onto the second surface of the wafer; the third fluid injection component is used to inject dilute sulfuric acid / hydrogen peroxide onto the second surface of the wafer; and the fourth fluid injection component is used to inject drying gas onto the second surface of the wafer.

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