Pressure detection device, vacuum system and wafer thinning equipment

Abstract

The invention provides a pressure detection device, a vacuum system and wafer thinning equipment. The pressure detection device is used for detecting the pressure change of a vacuum system of the wafer thinning equipment, the pressure detection device comprises a pressure sensor and a pressure sensor pipeline, and the first end of the pressure sensor pipeline is connected to the pressure sensor. The second end of the pressure sensor pipeline is used for being connected with a fluid pipeline of the vacuum system. The pressure detection device can prolong the service life of the pressure sensor by providing the pressure sensor pipeline.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing; more specifically, the present application relates to a pressure detection device, a vacuum system and a wafer thinning equipment. Background Art

[0002] With the development of semiconductor manufacturing, chip packaging requires thinner wafers to reduce package size and thickness. Thinner wafers are also conducive to heat dissipation and reduce the temperature of the chip during operation. Wafer thinning refers to the mechanical or chemical mechanical grinding of the back of the wafer. During the thinning process, the flatness and thickness of the wafer need to be strictly controlled to ensure the quality and performance of the wafer.

[0003] During the wafer grinding process of the wafer thinning equipment, the wafer is fixed on the chuck table by using vacuum adsorption force to ensure the stability of the wafer during the grinding process. In order to ensure that the wafer is effectively adsorbed on the chuck table, it is necessary to detect the vacuum degree of the vacuum system of the wafer thinning equipment and monitor the pressure changes in the vacuum system. Summary of the invention

[0004] In view of this, the present application provides a pressure detection device, system and equipment to solve or at least alleviate one or more of the above-mentioned problems or other problems existing in the prior art.

[0005] In order to achieve the aforementioned objectives, the first aspect of the present application provides a pressure detection device, which is used to detect pressure changes in a vacuum system of a wafer thinning device, wherein the pressure detection device includes a pressure sensor and a pressure sensor pipeline, the first end of the pressure sensor pipeline is connected to the pressure sensor, and the second end of the pressure sensor pipeline is used to connect to the fluid pipeline of the vacuum system.

[0006] In the pressure detection device as described above, optionally, the pressure sensor is a diaphragm pressure sensor.

[0007] In the pressure detection device as described above, optionally, the pressure sensor is connected to the first end of the pressure sensor pipeline through a throttle.

[0008] In the pressure detection device as described above, optionally, a filter is provided in the pressure sensor pipeline, and the filter is located between the second end of the pressure sensor pipeline and the throttle.

[0009] In the pressure detection device as described above, optionally, the throttle has a fluid inlet and a fluid outlet, the fluid inlet and the fluid outlet are connected through a throttling hole, the aperture of the throttling hole is smaller than the fluid inlet and smaller than the fluid outlet, the throttling hole is used to control the flow rate of the fluid, the fluid inlet is connected to the first end of the pressure sensor pipeline, and the fluid outlet is connected to the pressure sensor.

[0010] In the pressure detection device as described above, optionally, the throttle has one or more throttle holes, and the throttle holes are eccentrically arranged relative to the fluid inlet and the fluid outlet.

[0011] In the pressure detection device as described above, optionally, the throttle has a plurality of throttle holes, and the plurality of throttle holes are evenly arranged circumferentially around the central axis of the throttle.

[0012] In the pressure detection device as described above, optionally, an internal thread and / or an external thread for connection is provided at the fluid inlet of the throttle, and an internal thread and / or an external thread for connection is provided at the fluid outlet.

[0013] In the pressure detection device as described above, optionally, an external thread is provided at one of the fluid inlet and the fluid outlet of the throttle, and a flange protruding radially outward is provided at the other of the fluid inlet and the fluid outlet.

[0014] In the pressure detection device as described above, optionally, external threads are provided at both the fluid inlet and the fluid outlet of the throttle, and a flange protruding radially outward is provided between the fluid inlet and the fluid outlet.

[0015] In order to achieve the aforementioned objective, a second aspect of the present application provides a vacuum system for a wafer thinning device, wherein the vacuum system comprises a pressure detection device as described in any one of the aforementioned first aspects.

[0016] In the vacuum system as described above, optionally, the vacuum system further comprises:

[0017] A work plate, the work plate having a work plate vacuum area for fixing the wafer by vacuum;

[0018] The fluid pipeline has a first end and a second end, and the first end of the fluid pipeline is connected to the vacuum area of ​​the working disk;

[0019] The branch of the fluid pipeline, the branch and the pressure sensor pipeline are in fluid communication with the second end of the fluid pipeline via a manifold.

[0020] In the vacuum system as described above, the branch includes a vacuum branch, a compressed air branch and a water supply branch, wherein the vacuum branch is used to control the vacuum environment of the vacuum system of the wafer thinning equipment, the compressed air branch is used to release compressed air to the vacuum area of ​​the working disk and the wafer, and the water supply branch is used to release water to the vacuum area of ​​the working disk and the wafer.

[0021] According to a third aspect of the present application, a wafer thinning device is provided, wherein the wafer thinning device has a vacuum system as described in any one of the aforementioned second aspects.

[0022] In the wafer thinning device as described above, optionally, the wafer thinning device further includes:

[0023] A grinding assembly, wherein the grinding assembly comprises a grinding spindle and a grinding wheel mounted on the grinding spindle, wherein a cooling water channel is provided at the grinding assembly, and an on-off valve is provided in the cooling water channel;

[0024] A chuck workbench, the chuck workbench includes a work disc, the work disc is provided with a work disc vacuum area for fixing the wafer, the work disc is mounted on the wafer thinning equipment through a bearing, and the fluid pipeline is connected to the work disc vacuum area at the first end of the fluid pipeline through a rotary joint and the bearing.

[0025] The pressure detection device of the present application includes a pressure sensor and a pressure sensor pipeline. The pressure sensor is suitable for connecting to the vacuum system of the wafer thinning equipment to detect the pressure change of the vacuum system. The first end of the pressure sensor pipeline is connected to the pressure sensor, and the second end of the pressure sensor pipeline is used to connect to the fluid pipeline of the vacuum system. The fluid pipeline includes a plurality of branches, and the branch includes the pressure sensor pipeline. The present application avoids all fluids passing through the pressure sensor by adding a pressure sensor pipeline, thereby reducing the risk of debris entering the pressure sensor and damaging the detection diaphragm.

[0026] In a further technical solution of the present application, the pressure sensor is connected to the first end of the pressure sensor pipeline through a throttle, and a filter is also provided. The filter is located between the second end of the pressure sensor pipeline and the throttle, which can further extend the life of the pressure sensor, reduce the maintenance cost of the wafer thinning equipment, and improve the reliability and stability of the wafer thinning equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The disclosure of the present application will become more apparent with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present application. In the drawings:

[0028] Figure 1A schematic block diagram of an embodiment of a pressure detection device of the present application;

[0029] Figure 2 A schematic block diagram of an embodiment of a wafer thinning device of the present application is shown in the figure;

[0030] Figure 3 for Figure 1 A schematic top view of a first embodiment of a throttle in FIG. Figure 4 for Figure 3 AA cross-sectional view of the throttle in FIG.

[0031] Figure 5 for Figure 1 A schematic top view of a second embodiment of the throttle in FIG. Figure 6 for Figure 5 AA cross-sectional view of the throttle in FIG.

[0032] Figure 7 for Figure 1 A schematic top view of a third embodiment of the throttle in FIG. Figure 8 for Figure 7 AA cross-sectional view of the throttle in FIG.

[0033] Fig. 9 for Figure 1 A schematic top view of a fourth embodiment of the throttle in FIG. Fig.10 for Fig. 9 AA cross-sectional view of the throttle in FIG.

[0034] Fig.11 for Figure 1 A schematic top view of a fifth embodiment of the throttle in FIG. Fig.12 for Fig.11 AA cross-sectional view of the throttle in FIG.

[0035] Fig.13 for Figure 1 A schematic top view of a sixth embodiment of the throttle in FIG. Fig.14 for Fig.13 AA cross-sectional view of the throttle in FIG.

[0036] Fig.15 for Figure 1 A schematic top view of a seventh embodiment of the throttle in FIG. Fig.16 for Fig.15 AA cross-sectional view of the throttle in FIG.

[0037] Fig.17 for Figure 1 A schematic top view of an eighth embodiment of the throttle in FIG. Fig.18 for Fig.17 AA cross-sectional view of the throttle in FIG.

[0038] Figure markings: 1-water inlet; 2-on-off valve; 3-cooling water channel; 4-grinding spindle; 5-grinding wheel; 6-wafer; 7-working disk vacuum area; 8-working disk; 9-bearing; 10-rotating joint; 11-fluid pipeline; 12-valve; 13-water supply branch; 14-compressed air branch; 15-vacuum branch; 16-pressure sensor; 17-throttle; 18-filter; 19-pressure sensor pipeline; 20-collecting piece; 22-throttle hole; 23-internal thread; 24-external thread; 25-fluid inlet; 26-fluid outlet. DETAILED DESCRIPTION

[0039] With reference to the accompanying drawings and specific embodiments, the structure, composition, characteristics and advantages of the pressure detection device, vacuum system and wafer thinning equipment of the present application will be explained below in an exemplary manner. However, all descriptions should not be used to form any limitations on the present application.

[0040] For any single technical feature described or implied in the embodiments mentioned in this document, or any single technical feature displayed or implied in the accompanying drawings, this application still allows any combination or deletion between these technical features (or their equivalents) without any technical obstacles, and thus it should be considered that these more embodiments according to this application are also within the scope of the description of this document.

[0041] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features.

[0042] It should also be noted that the orientation or positional relationship indicated by the terms "upper" and "lower" is based on the orientation or positional relationship of the structure of the pressure detection device shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0043] During the grinding process of the wafer, the chuck table sucks the wafer through vacuum. Pressure measurement is one of the vacuum detection methods. By installing a pressure sensor, the pressure changes in the vacuum system can be monitored in real time. During the grinding process of the wafer, cooling water is used to treat the debris generated by grinding. Since the chuck table sucks the wafer through vacuum, the debris and cooling water generated by grinding will be sucked into the fluid pipeline along the periphery of the wafer. During grinding and when the wafer is removed after grinding, the debris and cooling water may also be sucked into the internal diaphragm detection position of the pressure sensor installed on the pipeline along the fluid pipeline, which will damage the pressure sensor. The present application proposes a pressure detection device.

[0044] Figure 1 This is a schematic block diagram of an embodiment of a pressure detection device of the present application, in which a pressure sensor 16 is shown.

[0045] like Figure 1 As shown, the pressure detection device may include a pressure sensor 16, a pressure sensor pipeline 19, and an optional throttle 17 and a filter 18. In this example, the first end of the pressure sensor pipeline 19 may be connected to the pressure sensor 16, and the pressure sensor 16 is used to detect the pressure change of the vacuum system, and the second end of the pressure sensor pipeline 19 may be used to connect to the fluid pipeline 11 of the vacuum system of the wafer thinning equipment (see Figure 2 ) to detect changes in pressure or vacuum in the vacuum system.

[0046] According to this embodiment, by adding the pressure sensor pipeline 19, it is possible to prevent the entire fluid from passing through the pressure sensor 16, thereby reducing the risk of debris entering the pressure sensor 16 and damaging the detection components.

[0047] In different embodiments, the pressure sensor 16 may be a diaphragm pressure sensor, and its detection component may be a detection diaphragm. In optional embodiments, any pressure sensor that can detect the pressure change of the vacuum system of the wafer thinning equipment falls within the protection scope of this application. The diaphragm pressure sensor measures the pressure through the deformation of the film, and the external pressure is fed back to the internal detection diaphragm of the diaphragm pressure sensor, causing it to bend or deform.

[0048] In the vacuum system of the wafer thinning equipment, the pressure sensor 16 can help monitor and control the vacuum degree by detecting the pressure difference to ensure that the wafer 6 (see Figure 2 ) processing quality. Vacuum degree can refer to the pressure difference relative to atmospheric pressure. When the ambient pressure is lower than atmospheric pressure, a vacuum is formed.

[0049] In an alternative embodiment, the pressure sensor 16 may be connected to the first end of the pressure sensor line 19 via a throttle 17 .

[0050] It is understood that during the back grinding process of wafer thinning, cooling water is used to treat the debris generated by grinding. Figure 2 The working disk 8 sucks the wafer 6 through vacuum. At this time, the fluid pipeline 11 is under negative pressure, so the debris and cooling water generated by grinding will be sucked into the fluid pipeline 11 along the outer periphery of the wafer 6. At this time, since a pressure sensor pipeline 19 is provided and the pressure sensor 16 is not directly installed on the fluid pipeline 11, the debris and cooling water generated by grinding can be slowed down or prevented from being sucked into the diaphragm detection position inside the pressure sensor 16 along the fluid pipeline 11.

[0051] In addition, after grinding is completed, the wafer 6 needs to be removed from the work plate 8, the vacuum of the fluid pipeline 11 needs to be turned off, and the positive pressure needs to be turned on. The wafer 6 is released by opening the compressed air branch 14 and / or the water supply branch 13. At this time, since a pressure sensor pipeline 19 is provided and the pressure sensor 16 is not directly installed on the fluid pipeline 11, the transmission of debris in the fluid pipeline 11 to the internal detection diaphragm position of the pressure sensor 16 can be slowed down or avoided.

[0052] Here, positive pressure refers to a state in which the pressure in a closed space or a pipe is higher than the atmospheric pressure relative to the atmospheric pressure. Correspondingly, negative pressure refers to a state in which the pressure in a closed space or a pipe is lower than the atmospheric pressure relative to the atmospheric pressure. During the grinding process of the wafer 6, positive pressure is used to release the wafer 6, and negative pressure is used to evacuate. When cooling water and / or debris reaches the inside of the pressure sensor 16 to check the diaphragm position, it may cause damage to the pressure sensor 16, thereby affecting the processing quality and efficiency of the wafer 6, so it is necessary to alleviate or avoid this situation.

[0053] During the grinding process of the wafer 6, if the wafer 6 is not on the work plate 8, the liquid on the workbench may be sucked into the fluid pipeline 11 and generate droplet vibration during the vacuuming process, and this vibration may also cause damage to the internal detection diaphragm of the pressure sensor 16. A throttle 17 is arranged at the front end of the pressure sensor 16 to reduce the inertial rush of water and block large particles to protect the pressure sensor 16 when the pressure changes caused by the switching between positive pressure and negative pressure.

[0054] exist Figure 1 In the example, a filter 18 is optionally provided in the pressure sensor pipeline 19, and the filter 18 is located between the second end of the pressure sensor pipeline 19 and the throttle 17. The filter 18 can filter out debris and silicon powder in the fluid to prevent them from being transmitted to the throttle 17 and the internal diaphragm detection position of the pressure sensor 16, which can avoid clogging of the throttle 17 and extend the life of the pressure sensor 16, ensure the measurement accuracy and long-term stability of the pressure sensor 16, reduce the maintenance cost of the wafer thinning equipment, and improve the reliability and stability of the wafer thinning equipment.

[0055] In different embodiments, the type of filter is not limited, such as ceramic filters, any filter that can be used to filter debris and silicon powder in the fluid to protect the sensor and the throttle 17 from damage is considered to fall within the protection scope of the present application.

[0056] Figure 2 This is a schematic block diagram of an embodiment of a wafer thinning device of the present application, in which a wafer 6 is shown.

[0057] like Figure 2 As shown, the vacuum system of the wafer thinning equipment may include a working disk 8, a fluid pipeline 11, and further branches of the fluid pipeline 11, such as but not limited to a vacuum branch 15, a compressed air branch 14 and a water supply branch 13.

[0058] The vacuum system includes a work disk 8, which has a work disk vacuum area 7 for fixing the wafer 6 through vacuum. By extracting the air between the work disk 8 and the wafer 6, a vacuum environment is formed, thereby firmly adsorbing the wafer 6 on the work disk 8, thereby preventing the wafer 6 from shifting or rotating during the processing process.

[0059] The first end of the fluid pipeline 11 is connected to the working disk vacuum area 7, and the second end of the fluid pipeline 11 is connected to the manifold 20. The manifold 20 is a component that can bring multiple pipelines together to a common connection point, which allows different fluid paths to communicate at one point for centralized control, distribution or mixing.

[0060] In the illustrated embodiment, the collecting piece 20 may be a five-way collecting piece, which is capable of connecting five different pipelines at the same time.

[0061] In an optional embodiment, the collection piece 20 can be connected to different branches, such as but not limited to a compressed air branch 14, a water supply branch 13, and a vacuum branch 15. The vacuum branch 15 can be connected to a vacuum pump to extract gas in the vacuum system to create a vacuum environment for adsorbing the wafer 6. The compressed air branch 14 can be used to supply compressed air between the working disk vacuum area 7 and the wafer 6, and the water supply branch 13 can be used to supply water between the working disk vacuum area 7 and the wafer 6, thereby releasing the wafer.

[0062] The compressed air branch 14, the water supply branch 13, and the vacuum branch 15 may be provided with valves 12 respectively, for opening and closing the connection between the branch and the fluid pipeline 11. When each branch needs to be connected with the fluid pipeline 11, the valve 12 is opened to allow the fluid to pass smoothly; when each branch does not need to be connected with the fluid pipeline 11, the valve 12 is closed, and the precise control of the fluid in each branch is achieved by controlling the opening and closing of the valve 12.

[0063] It can be understood that before and during grinding, the valves 12 of the compressed air branch 14 and the water supply branch 13 can be controlled to be closed, and the valve 12 of the vacuum branch 15 can be opened, so that the vacuum degree of the vacuum system of the wafer thinning equipment meets the requirements of adsorbing the wafer 6; after grinding, the valve 12 of the vacuum branch 15 can be controlled to be closed, and the valve 12 of the compressed air branch 14 and / or the water supply branch 13 can be opened to supply air and / or water between the vacuum area 7 of the working disk and the wafer 6, so that the pressure in the vacuum system is positive pressure, so that the wafer 6 can be removed from the vacuum area 7 of the working disk. In different embodiments, the type of valve 12 is not limited, and different valves 12 such as solenoid valves or air hole valves all fall within the protection scope of this application.

[0064] exist Figure 2 In an example, a wafer thinning apparatus may include a grinding assembly and a chuck table.

[0065] As shown in the figure, the grinding assembly may include a grinding spindle 4 and a grinding wheel 5, and the grinding wheel 5 may be mounted on the grinding spindle 4 for grinding a wafer 6. A cooling water channel 3 may also be provided at the grinding assembly for cooling during grinding. In order to control the on-off and flow rate of the cooling water, an on-off valve 2 may be provided in the cooling water channel 3.

[0066] The cooling water channel 3 can be passed from the center of the grinding spindle 4 to the grinding part. The on-off valve 2 can be a valve for controlling the flow of water, which is installed at the water inlet 1. It can be understood that during the thinning process of the wafer 6, cooling water can be used to reduce the temperature of the grinding area to prevent the heat generated by friction from overheating the equipment; if the debris generated during the grinding process is not handled in time, it will pollute the working environment, and cooling water is used to flush the debris away from the workbench.

[0067] Specifically, Figure 2 As shown, the on-off valve 2 can be set at one end of the grinding spindle 4, and the grinding wheel 5 can be installed at the other end. A central cooling water channel 3 is set at the center of the grinding spindle 4 to serve as a channel for water flow. One end of the central cooling water channel 3 is connected to the on-off valve 2, and the other end leads to the center of the grinding wheel 5. The grinding wheel 5 is installed below the grinding spindle 4 and above the working disk 8 to grind the wafer 6. The grinding spindle 4 is connected to the grinding wheel 5 and drives the grinding wheel 5 to rotate. The grinding spindle 4 is driven by a driving device (not shown). In an optional embodiment, the driving device can be a motor.

[0068] As shown in the figure, the chuck table may include a work plate 8, and the work plate 8 may be provided with a work plate vacuum area 7 for fixing the wafer 6. The work plate is mounted on the wafer thinning device through a bearing 9, and a fluid pipeline 11 is connected to the work plate vacuum area 7 at a first end of the fluid pipeline 11 through a rotary joint 10 and the bearing 9.

[0069] Specifically, during the thinning process of the wafer 6, the wafer 6 is placed on the working disk 8, and the working disk 8 has a working disk vacuum area 7 that generates vacuum to fix the wafer 6. Through the vacuum system, the wafer 6 is tightly adsorbed in the working disk vacuum area 7. The wafer 6 can be driven by the working disk 8 to rotate, and the grinding wheel 5 can be driven by the grinding spindle 4 to rotate in the opposite direction. The rotation axes of the working disk 8 and the grinding spindle 4 are parallel to each other. The sharpness of the grinding wheel 5 is used to grind the wafer 6, and the grinding depth can be controlled by adjusting the distance between the grinding wheel 5 and the wafer 6. The bearing 9 is installed below the working disk 8 to support the rotation of the working disk 8. The rotary joint 10 is located below the bearing 9 and is connected to the bearing 9. The rotary joint 10 leads the fluid pipeline 11 to the working disk vacuum area 7, which can enable the fluid to flow between the rotating working disk 8 and the stationary fluid passage.

[0070] Figure 3-Figure 18 Shows Figure 1 Different embodiments of the throttle 17 in FIG.

[0071] like Figure 3-Figure 18 As shown, the throttle 17 may have a fluid inlet 25 and a fluid outlet 26, and the fluid inlet 25 and the fluid outlet 26 are connected through a throttle hole 22. The throttle hole 22 may be eccentrically arranged relative to the fluid inlet 25 and the fluid outlet 26. The aperture of the throttle hole 22 is smaller than the fluid inlet 25 and smaller than the fluid outlet 26, and the throttle hole 22 is used to control the flow rate of the fluid. The fluid inlet 25 can be used to connect to the first end of the pressure sensor pipeline 19, and the fluid outlet 26 can be used to connect to the pressure sensor 16, so that the fluid will first enter the throttle 17 before entering the pressure sensor 16, reducing the impact of the fluid on the pressure sensor 16.

[0072] In an optional embodiment, the throttle 17 has one or more throttle holes 22, such as but not limited to one or three shown in the figure. The design of the single throttle hole 22 is simple, easy to manufacture and maintain. When the throttle 17 has multiple throttle holes 22, each throttle hole 22 can have different sizes, shapes and / or distributions, which can more finely control the flow rate and pressure of the fluid. In an optional embodiment, the multiple throttle holes 22 are evenly arranged around the central axis of the throttle 17. The advantage of this arrangement is that the throttle holes 22 evenly arranged circumferentially can make the fluid more evenly distributed when it flows out. Multiple throttle holes 22 can provide redundancy. If one of the throttle holes 22 fails due to debris blockage or other reasons, the other throttle holes 22 can still work, keeping the function of the throttle 17 effective. Multiple throttle holes 22 can also be used for more complex flow regulation, for example, the total flow of the system can be adjusted by opening or closing different throttle holes 22. In different embodiments, the type of throttle can be selected according to actual needs.

[0073] In an optional embodiment, an internal thread 23 and / or an external thread 24 for connection are respectively provided at the fluid inlet 25 and the fluid outlet 26 of the throttle 17. For example, Figure 3 for Figure 1 A schematic top view of a first embodiment of a throttle in FIG. Figure 4 for Figure 3 AA cross-sectional view of the throttle in FIG. Figure 3 and Figure 4 The throttle 17 shown is a single-hole throttle with an external thread 24 disposed at a fluid inlet 25 and an internal thread 23 disposed at a fluid outlet 26 . Figure 3 A restriction orifice 22 is shown. Figure 4 for Figure 3 The AA cross-sectional view shows that an external thread 24 is provided at the fluid inlet 25, and the fluid flows from the fluid inlet 25 to the fluid outlet 26 through the throttle hole 22. Figure 3 and Figure 4 In the example, the throttle hole 22 is an eccentrically arranged circular throttle hole. In an optional embodiment, the throttle hole can have various forms, such as elliptical, polygonal and other different shapes. In the specific implementation process, it can be designed according to the properties of the fluid, flow rate, etc.

[0074] exist Figure 3 and Figure 4 In the embodiment of the throttle 17, the throttle hole 22 is closer to the fluid inlet 25, providing a far buffer distance on the fluid outlet 26 side, which can relieve the fluid. In addition, on the side of the fluid inlet 25, the end face of the throttle hole 22 is a plane.

[0075] Figure 5 for Figure 1 A schematic top view of a second embodiment of the throttle in FIG. Figure 6 for Figure 5 AA cross-sectional view of the throttle in FIG. Figure 5 and Figure 6 The throttle 17 shown is a single-hole throttle with an internal thread 23 disposed at a fluid inlet 25 and an external thread 24 disposed at a fluid outlet 26. In this embodiment, the diameter of the fluid inlet 25 is larger than that of the fluid outlet 26, and the throttle hole 22 is closer to the fluid outlet 25.

[0076] Figure 7 for Figure 1 A schematic top view of a third embodiment of the throttle in FIG. Figure 8 for Figure 7 AA cross-sectional view of the throttle in FIG. Figure 7 and Figure 8The restrictor 17 shown is a single-hole restrictor with external threads 24 disposed at a fluid inlet 25 and a fluid outlet 26. In this embodiment, the diameter of the fluid inlet 25 is the same as that of the fluid outlet 26, and the restrictor hole 22 is located between the fluid inlet 25 and the fluid outlet 26.

[0077] Fig. 9 for Figure 1 A schematic top view of a fourth embodiment of the throttle in FIG. Fig.10 for Fig. 9 AA cross-sectional view of the throttle in FIG. Fig. 9 and Fig.10 The restrictor 17 shown is a single-hole restrictor with internal threads 23 disposed at a fluid inlet 25 and a fluid outlet 26. In this embodiment, the diameter of the fluid inlet 25 is the same as that of the fluid outlet 26, and the restrictor hole 22 is located between the fluid inlet 25 and the fluid outlet 26.

[0078] Fig.11 for Figure 1 A schematic top view of a fifth embodiment of the throttle in FIG. Fig.12 for Fig.11 AA cross-sectional view of the throttle in FIG. Fig.11 and Fig.12 The throttle 17 shown is a multi-hole throttle with an external thread 24 disposed at a fluid inlet 25 and an internal thread 23 disposed at a fluid outlet 26. In this embodiment, the throttle hole 22 is closer to the fluid inlet 25, providing a long buffer distance on the side of the fluid outlet 26 to relieve the fluid. In addition, on the side of the fluid inlet 25, the end face of the throttle hole 22 is a plane.

[0079] Fig.13 for Figure 1 A schematic top view of a sixth embodiment of the throttle in FIG. Fig.14 for Fig.13 AA cross-sectional view of the throttle in FIG. Fig.13 and Fig.14 The restrictor 17 shown is a multi-hole restrictor with an internal thread 23 disposed at a fluid inlet 25 and an external thread 24 disposed at a fluid outlet 26. In this embodiment, the diameter of the fluid inlet 25 is larger than that of the fluid outlet 26, and the restrictor hole 22 is closer to the fluid outlet 25.

[0080] Fig.15 for Figure 1 A schematic top view of a seventh embodiment of the throttle in FIG. Fig.16 for Fig.15 AA cross-sectional view of the throttle in FIG. Fig.15 and Fig.16The restrictor 17 shown is a multi-hole restrictor with external threads 24 disposed at a fluid inlet 25 and a fluid outlet 26. In this embodiment, the diameter of the fluid inlet 25 is the same as that of the fluid outlet 26, and the restrictor hole 22 is located between the fluid inlet 25 and the fluid outlet 26.

[0081] Fig.17 for Figure 1 A schematic top view of an eighth embodiment of the throttle in FIG. Fig.18 for Fig.17 AA cross-sectional view of the throttle in FIG. Fig.17 and Fig.18 The internal thread 23 shown is provided at the multi-hole restrictor of the fluid inlet 25 and the fluid outlet 26. In this embodiment, the diameter of the fluid inlet 25 is the same as the diameter of the fluid outlet 26, and the restrictor hole 22 is located between the fluid inlet 25 and the fluid outlet 26. The internal thread 23 and the external thread 24 are two common thread forms, the internal thread 23 refers to the thread formed on the inner surface of the hole, and the external thread 24 refers to the thread formed on the outer surface of the hole. Different thread settings allow the restrictor to be selected according to different application requirements to achieve the best fluid control effect.

[0082] like Figure 4 , 6 As shown in , 12, and 14, an external thread 24 is provided at one of the fluid inlet 25 and the fluid outlet 26 of the throttle 17, and a flange protruding radially outward is provided at the other of the fluid inlet 25 and the fluid outlet 26, for example, the flange is provided at the tail end of the external thread 24, so as to provide a stop after the throttle 17 is engaged with other pipe fittings, and ensure that the throttle 17 does not move axially in the pipeline after installation. The outer diameter of the throttle 17 will change from the external thread 24 to the flange, for example, forming a step. In the illustrated embodiment, the thread tail end, for example, refers to an incomplete thread portion formed at the end of the effective length of the thread when processing the thread, which is usually a transition area that gradually becomes shallower until it disappears. The thread starting end corresponds to the tail end, and the thread starting end is the part where the thread begins to form. In this example, the starting end is used to guide the pipe fitting to the spiral installation of the thread. Figure 8 , 16 As shown, external threads 24 are provided at both the fluid inlet 25 and the fluid outlet 26 of the throttle 17, and a flange is formed between the fluid inlet 25 and the fluid outlet 26. Fig.10 , 18 As shown, internal threads 23 are provided at the fluid inlet 25 and the fluid outlet 26 of the throttle 17, and no external threads are provided, so the appearance of the throttle 17 can be a straight barrel type without external flanges. In this embodiment, the threaded connection can provide a certain fixing force to prevent the throttle 17 from moving in the pipeline system.

[0083] The technical solution of the present application is applicable to the wafer thinning process of the wafer thinning equipment, and can reduce the damage to the pressure sensor caused by the intrusion of water when the pressure in the fluid pipeline changes. According to a further optional technical solution, during the processing, considering that the debris and silicon powder in the fluid may cause damage to the pressure sensor, filtering out large particles through a filter can avoid throttle blockage, and at the same time, the throttle filters out the large particles that may still exist and reduces the impact of water, which can extend the life of the pressure sensor, reduce the equipment maintenance cost, and improve the reliability and stability of the equipment.

[0084] The above implementation methods are only used to illustrate the embodiments of the present application, and are not limitations on the embodiments of the present application. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the embodiments of the present application. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present application. The scope of patent protection of the embodiments of the present application should be limited by the claims.

Claims

1. A pressure detection device, which is used to detect the pressure change of the vacuum system of a wafer thinning device, characterized in that: The pressure detection device comprises a pressure sensor (16) and a pressure sensor pipeline (19), wherein a first end of the pressure sensor pipeline (19) is connected to the pressure sensor (16), and a second end of the pressure sensor pipeline (19) is used to connect to a fluid pipeline (11) of the vacuum system.

2. The pressure detection device according to claim 1, characterized in that: The pressure sensor (16) is a diaphragm pressure sensor.

3. The pressure detection device according to claim 1 or 2, characterized in that: The pressure sensor (16) is connected to a first end of the pressure sensor pipeline (19) via a throttle (17).

4. The pressure detection device according to claim 3, characterized in that: A filter (18) is arranged in the pressure sensor pipeline (19), and the filter (18) is located between the second end of the pressure sensor pipeline (19) and the throttle (17).

5. The pressure detection device according to claim 3, characterized in that: The throttle (17) has a fluid inlet (25) and a fluid outlet (26), wherein the fluid inlet (25) and the fluid outlet (26) are connected via a throttle hole (22), wherein the aperture of the throttle hole (22) is smaller than that of the fluid inlet (25) and smaller than that of the fluid outlet (26), and the throttle hole (22) is used to control the flow rate of the fluid, wherein the fluid inlet (25) is connected to the first end of the pressure sensor pipeline (19), and the fluid outlet (26) is connected to the pressure sensor (16).

6. The pressure detection device according to claim 5, characterized in that: The throttle (17) has one or more throttle holes (22), and the throttle holes (22) are eccentrically arranged relative to the fluid inlet (25) and the fluid outlet (26).

7. The pressure detection device according to claim 5, characterized in that: The throttle (17) has a plurality of throttle holes (22), and the plurality of throttle holes (22) are evenly arranged in a circumferential direction around a central axis of the throttle (17).

8. The pressure detection device according to claim 5, characterized in that: An internal thread (23) and / or an external thread (24) for connection is provided at the fluid inlet (25) of the throttle (17), and an internal thread (23) and / or an external thread (24) for connection is provided at the fluid outlet (26).

9. The pressure detection device according to claim 5, characterized in that: An external thread (24) is provided at one of the fluid inlet (25) and the fluid outlet (26) of the throttle (17), and a flange protruding radially outward is provided at the other of the fluid inlet (25) and the fluid outlet (26).

10. The pressure detection device according to claim 5, characterized in that: External threads (24) are provided at both the fluid inlet (25) and the fluid outlet (26) of the throttle (17), and a flange protruding radially outward is provided between the fluid inlet (25) and the fluid outlet (26).

11. A vacuum system for wafer thinning equipment, characterized in that: The vacuum system comprises the pressure detection device according to any one of claims 1 to 10, and the vacuum system further comprises: A working plate (8), wherein the working plate (8) has a working plate vacuum area (7) for fixing the wafer (6) by vacuum; The fluid pipeline (11), the fluid pipeline (11) has a first end and a second end, the first end of the fluid pipeline (11) is connected to the vacuum area (7) of the working disk; The branch of the fluid pipeline (11), the branch and the pressure sensor pipeline (19) are in fluid communication with the second end of the fluid pipeline (11) via a collecting piece (20).

12. The vacuum system according to claim 11, characterized in that The branch circuit includes a vacuum branch circuit (15), a compressed air branch circuit (14) and a water supply branch circuit (13), wherein the vacuum branch circuit (15) is used to control the vacuum environment of the vacuum system of the wafer thinning equipment, the compressed air branch circuit (14) is used to release compressed air between the working disk vacuum area (7) and the wafer (6), and the water supply branch circuit (13) is used to release water between the working disk vacuum area (7) and the wafer (6).

13. A wafer thinning device, characterized in that: The wafer thinning equipment has a vacuum system as claimed in claim 11 or 12, and the wafer thinning equipment further comprises: A grinding assembly, the grinding assembly comprising a grinding spindle (4) and a grinding wheel (5) mounted on the grinding spindle (4), a cooling water channel (3) being provided at the grinding assembly, and an on-off valve (2) being provided in the cooling water channel (3); A chuck workbench, the chuck workbench comprising the work disc (8), the work disc (8) being provided with a work disc vacuum area (7) for fixing the wafer (6), the work disc being mounted on the wafer thinning device via a bearing (9), the fluid pipeline (11) being connected to the work disc vacuum area (7) at a first end of the fluid pipeline (11) via a rotary joint (10) and the bearing (9).

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