Pressure detection device, vacuum system and wafer thinning equipment

Abstract

The utility model 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 particularly, the present application relates to a pressure detection device, a vacuum system and a wafer thinning apparatus. BACKGROUND

[0002] With the development of the field of semiconductor manufacturing, chip packaging requires thinner wafers to reduce the size and thickness of the package, and thinner wafers are beneficial to heat dissipation, reducing the temperature of the chip during operation. Wafer thinning process refers to grinding the back of the wafer by mechanical or chemical mechanical method. 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 grinding of the wafer by the wafer thinning apparatus, the wafer is fixed on the chuck table by using the 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 apparatus and monitor the pressure change in the vacuum system. CONTENT OF THE INVENTION

[0004] Therefore, the present application provides a pressure detection device, system and apparatus to solve or at least alleviate one or more of the above problems or other aspects of the prior art.

[0005] In order to achieve the foregoing purpose, the first aspect of the present application provides a pressure detection device for detecting the pressure change of a vacuum system of a wafer thinning apparatus, wherein the pressure detection device comprises a pressure sensor and a pressure sensor pipeline, a first end of the pressure sensor pipeline is connected to the pressure sensor, and a second end of the pressure sensor pipeline is used to connect a fluid pipeline of the vacuum system.

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

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

[0009] In the pressure detection device as claimed in any one of the preceding aspects, optionally, the flow restrictor has a fluid inlet and a fluid outlet, the fluid inlet and the fluid outlet are in communication through a flow restrictor orifice, the flow restrictor orifice has an orifice diameter smaller than the fluid inlet and smaller than the fluid outlet, the flow restrictor orifice is configured to restrict the flow of fluid, the fluid inlet is connected to the first end of the pressure sensor conduit, and the fluid outlet is connected to the pressure sensor.

[0010] In the pressure detection device as claimed in any one of the preceding aspects, optionally, the flow restrictor has one or more flow restrictor orifices, and the flow restrictor orifices are arranged eccentrically with respect to the fluid inlet and the fluid outlet.

[0011] In the pressure detection device as claimed in any one of the preceding aspects, optionally, the flow restrictor has a plurality of flow restrictor orifices, and the plurality of flow restrictor orifices are arranged circumferentially uniformly around a central axis of the flow restrictor.

[0012] In the pressure detection device as claimed in any one of the preceding aspects, optionally, an internal thread and / or an external thread for connection is provided at the fluid inlet of the flow restrictor, and an internal thread and / or an external thread for connection is provided at the fluid outlet of the flow restrictor.

[0013] In the pressure detection device as claimed in any one of the preceding aspects, optionally, an external thread is provided at one of the fluid inlet and the fluid outlet of the flow restrictor, and a radially outwardly protruding flange is provided at the other of the fluid inlet and the fluid outlet.

[0014] In the pressure detection device as claimed in any one of the preceding aspects, optionally, an external thread is provided at both the fluid inlet and the fluid outlet of the flow restrictor, and a radially outwardly protruding flange is provided between the fluid inlet and the fluid outlet.

[0015] To achieve the foregoing object, a second aspect of the present application provides a vacuum system for a wafer thinning apparatus, wherein the vacuum system comprises the pressure detection device according to any one of the preceding first aspects.

[0016] In the vacuum system as claimed in any one of the preceding aspects, optionally, the vacuum system further comprises:

[0017] a worktable having a worktable vacuum region configured to hold a wafer by vacuum;

[0018] the fluid conduit having a first end and a second end, the first end of the fluid conduit being connected to the worktable vacuum region;

[0019] a branch of the fluid conduit, the branch and the pressure sensor conduit being in fluid communication with the second end of the fluid conduit via a junction.

[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 device, the compressed air branch is used to release compressed air between the worktable vacuum area and the wafer, and the water supply branch is used to release water between the worktable vacuum area 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 the vacuum system according to any one of the preceding second aspects.

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

[0023] The grinding assembly includes a grinding spindle and a grinding wheel mounted on the grinding spindle, and a cooling water channel is arranged at the grinding assembly, and a on-off valve is arranged in the cooling water channel;

[0024] The chuck table includes a worktable provided with a worktable vacuum area for fixing the wafer, and the worktable is mounted on the wafer thinning device through a bearing, and the fluid pipeline is communicated with the worktable 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 adapted to be connected to the vacuum system of the wafer thinning device 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 the fluid pipeline of the vacuum system, the fluid pipeline includes a plurality of branches, and the branch includes the pressure sensor pipeline. By adding the pressure sensor pipeline, the present application avoids that the fluid passes through the pressure sensor, reduces the risk of debris entering the inside of the pressure sensor and damaging the detection diaphragm.

[0026] In the further technical solutions of the present application, the pressure sensor is connected to the first end of the pressure sensor pipeline through a restrictor, and a filter is further arranged between the second end of the pressure sensor pipeline and the restrictor, which can further prolong the service life of the pressure sensor, reduce the maintenance cost of the wafer thinning device, and improve the reliability and stability of the wafer thinning device. BRIEF DESCRIPTION OF DRAWINGS

[0027] The disclosure of the present application will be 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 1This is a schematic block diagram of one embodiment of the pressure detection device of this application;

[0029] Figure 2 This is a schematic block diagram of one embodiment of the wafer thinning apparatus of this application, showing a wafer;

[0030] Figure 3 for Figure 1 A top view of the first embodiment of the throttle in the diagram. Figure 4 for Figure 3 A schematic diagram of the throttle device in AA section;

[0031] Figure 5 for Figure 1 A top view of the second embodiment of the throttle in the diagram. Figure 6 for Figure 5 A schematic diagram of the throttle device in AA section;

[0032] Figure 7 for Figure 1 A top view of the third embodiment of the throttle in the diagram. Figure 8 for Figure 7 A schematic diagram of the throttle device in AA section;

[0033] Figure 9 for Figure 1 A top view of the fourth embodiment of the throttle in the diagram. Figure 10 for Figure 9 A schematic diagram of the throttle device in AA section;

[0034] Figure 11 for Figure 1 A top view of the fifth embodiment of the throttle in the diagram. Figure 12 for Figure 11 A schematic diagram of the throttle device in AA section;

[0035] Figure 13 for Figure 1 A top view of the sixth embodiment of the throttle in the diagram. Figure 14 for Figure 13 A schematic diagram of the throttle device in AA section;

[0036] Figure 15 for Figure 1 A top view of the seventh embodiment of the throttle in the diagram. Figure 16 for Figure 15 A schematic diagram of the throttle device in AA section;

[0037] Figure 17 for Figure 1 A top view of the eighth embodiment of the throttle in the diagram. Figure 18 for Figure 17 A schematic diagram of the AA cross-section of the throttle in the diagram.

[0038] Reference numerals: 1 - water inlet; 2 - on-off valve; 3 - cooling water passage; 4 - grinding spindle; 5 - grinding wheel; 6 - wafer; 7 - worktable vacuum area; 8 - worktable; 9 - bearing; 10 - rotary joint; 11 - fluid line; 12 - valve; 13 - water supply branch; 14 - compressed air branch; 15 - vacuum branch; 16 - pressure sensor; 17 - restrictor; 18 - filter; 19 - pressure sensor line; 20 - manifold; 22 - orifice; 23 - internal thread; 24 - external thread; 25 - fluid inlet; 26 - fluid outlet. DETAILED DESCRIPTION

[0039] With reference to the drawings and specific embodiments, the structure, composition, features and advantages of the pressure detection device, vacuum system and wafer thinning apparatus of the present application will be described below in an exemplary manner, however, all the descriptions shall not be used to form any limitation on the present application.

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

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

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

[0043] In the process of grinding the wafer, the chuck table sucks the wafer by vacuum. Pressure measurement is one of the vacuum detection methods, by installing a pressure sensor, the pressure change in the vacuum system can be monitored in real time. In the process of grinding the wafer, the generated debris will be treated by cooling water, since the chuck table sucks the wafer by vacuum, the debris and cooling water generated by grinding will be sucked into the fluid pipeline along the outer periphery of the wafer, and when the wafer is removed during grinding and after grinding, the debris and cooling water may also be sucked into the membrane detection position of the pressure sensor installed on the pipeline along with the fluid pipeline, which will damage the pressure sensor. The pressure detection device is provided.

[0044] Figure 1 The schematic block diagram of one embodiment of the pressure detection device of the present application is shown, which shows the pressure sensor 16.

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

[0046] According to this embodiment, by adding the pressure sensor pipeline 19, it can avoid that the fluid passes through the pressure sensor 16, and reduce the risk of debris entering the internal detection components of the pressure sensor 16.

[0047] In different embodiments, the pressure sensor 16 can be a diaphragm pressure sensor, and its detection component can be a detection diaphragm. In optional embodiments, any pressure sensor that can detect the pressure change of the vacuum system of the wafer thinning device falls within the protection scope of the present application. The diaphragm pressure sensor measures pressure by deformation of the thin 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 device, the pressure sensor 16 can help monitor and control the vacuum degree by detecting the pressure difference, so as to ensure the processing quality of the wafer 6 (see Figure 2 ).

[0049] In optional embodiments, the pressure sensor 16 can be connected to the first end of the pressure sensor pipeline 19 through the restrictor 17.

[0050] It is understood that during the backside grinding of wafer thinning, the debris generated by grinding is treated with cooling water, and meanwhile, referring to Figure 2 , the worktable 8 sucks the wafer 6 by vacuum, at this time, the fluid pipeline 11 is under negative pressure, so the debris generated by grinding and the cooling water are sucked into the fluid pipeline 11 along the outer periphery of the wafer 6, at this time, since the pressure sensor pipeline 19 is provided, the pressure sensor 16 is not directly installed on the fluid pipeline 11, so the debris generated by grinding and the cooling water are slowed down or avoided from being sucked into the internal diaphragm detection position of the pressure sensor 16 along the fluid pipeline 11.

[0051] In addition, after the grinding is completed, the wafer 6 needs to be removed from the worktable 8, the fluid pipeline 11 needs to be closed under vacuum and opened under positive pressure, and the wafer 6 is released by opening the compressed air branch 14 and / or the water supply branch 13, at this time, since the pressure sensor pipeline 19 is provided, the pressure sensor 16 is not directly installed on the fluid pipeline 11, so the debris in the fluid pipeline 11 is slowed down or avoided from being transmitted to the internal diaphragm detection position of the pressure sensor 16.

[0052] Here, the positive pressure refers to a state that the pressure in the enclosed space or pipeline is higher than the atmospheric pressure relative to the atmospheric pressure. Correspondingly, the negative pressure refers to a state that the pressure in the enclosed space or pipeline is lower than the atmospheric pressure relative to the atmospheric pressure. In the grinding process of the wafer 6, the positive pressure is used to release the wafer 6, and the negative pressure is used for vacuumizing. When the cooling water and / or the debris reach the internal diaphragm detection position of the pressure sensor 16, it may cause damage to the pressure sensor 16, and then affect the processing quality and efficiency of the wafer 6, so it is necessary to alleviate or avoid this situation.

[0053] In the grinding process of the wafer 6, if the wafer 6 is not on the worktable 8, the liquid on the worktable may be sucked into the fluid pipeline 11 and produce liquid droplet vibration in the vacuumizing process, which may also cause damage to the internal diaphragm detection position of the pressure sensor 16. The flow restrictor 17 arranged at the front end of the pressure sensor 16 can reduce the inertial impact of water and block large particles to protect the pressure sensor 16 when the pressure changes caused by the switching between the positive pressure and the negative pressure.

[0054] In the example of Figure 1 , the filter 18 is optionally 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 flow restrictor 17. The filter 18 can filter out the debris and silicon powder in the fluid, prevent them from being transmitted to the internal diaphragm detection position of the pressure sensor 16 and the flow restrictor 17, avoid the flow restrictor 17 from being blocked, prolong the service 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, and any filter that can be used to filter debris and silicon powder in the fluid to protect the sensor and throttle 17 from damage is considered to fall within the protection scope of this application.

[0056] Figure 2 This is a schematic block diagram of one embodiment of the wafer thinning apparatus of this application, showing wafer 6.

[0057] like Figure 2 As shown, the vacuum system of the wafer thinning equipment may include a working tray 8, a fluid line 11, and branches of the fluid line 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 by vacuum. By evacuating the air between the work disk 8 and the wafer 6, a vacuum environment is formed, thereby firmly adsorbing the wafer 6 onto the work disk 8 and preventing the wafer 6 from shifting or rotating during the processing.

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

[0060] In the illustrated embodiment, the manifold 20 can be a five-way manifold, which can connect five different pipelines.

[0061] In optional embodiments, the assembly 20 may connect 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 may be connected to a vacuum pump to extract gas from the vacuum system to create a vacuum environment for adsorbing the wafer 6. The compressed air branch 14 may be used to supply compressed air between the worktable vacuum region 7 and the wafer 6, and the water supply branch 13 may be used to supply water between the worktable vacuum region 7 and the wafer 6, thereby releasing the wafer.

[0062] Valves 12 can be installed in the compressed air branch 14, water supply branch 13, and vacuum branch 15 to open and close the connection between the branch and the fluid pipeline 11. When it is necessary to connect each branch to the fluid pipeline 11, the valve 12 is opened to allow the fluid to flow smoothly; when it is not necessary to connect each branch to the fluid pipeline 11, the valve 12 is closed. Precise control of the fluid in each branch is achieved by controlling the opening and closing of the valve 12.

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

[0064] In Figure 2 an example, the wafer thinning device can include a grinding assembly and a chuck table.

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

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

[0067] Specifically, as Figure 2 shown, the on-off valve 2 can be provided at one end of the grinding spindle 4, and the grinding wheel 5 can be installed at the other end. The center of the grinding spindle 4 is provided with a central cooling water channel 3 as a water flow channel, one end of the central cooling water channel 3 is connected with the on-off valve 2, and the other end passes through the center of the grinding wheel 5. The grinding wheel 5 is installed below the grinding spindle 4 and above the worktable 8, so as to grind the wafer 6. The grinding spindle 4 is connected with the grinding wheel 5 and drives the grinding wheel 5 to rotate, and 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 can include a worktable 8, and the worktable 8 can be provided with a worktable vacuum area 7 for fixing the wafer 6. The worktable is installed on the wafer thinning device through a bearing 9, and a fluid pipeline 11 communicates with the worktable 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 worktable 8, which has a worktable vacuum area 7 that generates vacuum to hold the wafer 6. The wafer 6 is tightly attracted to the worktable vacuum area 7 by the vacuum system. The wafer 6 can be spun by the worktable 8, and the grinding wheel 5 can be rotated in the opposite direction by the grinding spindle 4. The rotation axes of the worktable 8 and the grinding spindle 4 are parallel to each other. The wafer 6 is ground by the sharpness of the grinding wheel 5. The depth of grinding can be controlled by adjusting the distance between the grinding wheel 5 and the wafer 6. The bearing 9 is installed below the worktable 8 to support the spinning of the worktable 8. The rotary joint 10 is connected to the bearing 9 below the bearing 9. The rotary joint 10 leads the fluid line 11 to the worktable vacuum area 7, allowing fluid to flow between the rotating worktable 8 and the stationary fluid passage.

[0070] Figures 3-18 Different embodiments of the flow restrictor 17 are shown in Figure 1

[0071] As shown in Figures 3-18 , the flow restrictor 17 can have a fluid inlet 25 and a fluid outlet 26, which are connected by a flow restriction hole 22. The flow restriction hole 22 can be eccentrically arranged relative to the fluid inlet 25 and the fluid outlet 26. The flow restriction hole 22 has a smaller diameter than the fluid inlet 25 and the fluid outlet 26, and is used to restrict the flow of fluid. The fluid inlet 25 can be used to connect to the first end of the pressure sensor line 19, and the fluid outlet 26 can be used to connect to the pressure sensor 16, so that the fluid will first enter the flow restrictor 17 before entering the pressure sensor 16, reducing the impact of the fluid on the pressure sensor 16.

[0072] In alternative embodiments, the flow restrictor 17 has one or more flow restriction holes 22, such as but not limited to one or three as shown. The single flow restriction hole 22 design is simple, easy to manufacture and maintain. When the flow restrictor 17 has multiple flow restriction holes 22, each flow restriction hole 22 can have different sizes, shapes and / or distributions, allowing more precise control of fluid flow and pressure. In alternative embodiments, the plurality of flow restriction holes 22 are arranged uniformly around the central axis of the flow restrictor 17. The advantage of this arrangement is that the circumferentially uniform arrangement of flow restriction holes 22 can make the fluid more evenly distributed when flowing out. Multiple flow restriction holes 22 can provide redundancy, so that if one of the flow restriction holes 22 fails due to debris blockage or other reasons, the other flow restriction holes 22 can still work, maintaining the effectiveness of the flow restrictor 17. Multiple flow restriction holes 22 can also be used for more complex flow regulation, such as adjusting the total flow of the system by opening or closing different flow restriction holes 22. In different embodiments, the type of flow restrictor can be selected according to actual needs.

[0073] ​In an optional embodiment, internal threads 23 and / or external threads 24 for connection are respectively provided at the fluid inlet 25 and fluid outlet 26 of the throttle 17. For example, Figure 3 for Figure 1 A top view of the first embodiment of the throttle in the diagram. Figure 4 for Figure 3 A schematic diagram of the AA cross-section of the throttle in the diagram. Figure 3 and Figure 4 The throttle 17 shown is a single-hole throttle with an external thread 24 at the fluid inlet 25 and an internal thread 23 at the fluid outlet 26. Figure 3 The throttle 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 through the throttling hole 22 to the fluid outlet 26. Figure 3 and Figure 4 In the example, the throttling orifice 22 is an eccentrically positioned circular throttling orifice. In optional embodiments, the throttling orifice can take various forms, such as elliptical, polygonal, or other different shapes. In specific implementation, 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 orifice 22 is closer to the fluid inlet 25, providing a greater buffer distance on the fluid outlet 26 side, thus slowing down the fluid flow. Additionally, on the fluid inlet 25 side, the end face of the throttle orifice 22 is flat.

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

[0076] Figure 7 for Figure 1 A top view of the third embodiment of the throttle in the diagram. Figure 8 for Figure 7 A schematic diagram of the AA cross-section of the throttle in the diagram. Figure 7 and Figure 8The orifice 17 shown is a single hole orifice with external threads 24 at the fluid inlet 25 and internal threads 23 at the fluid outlet 26. In this embodiment, the fluid inlet 25 has the same diameter as the fluid outlet 26 and the orifice hole 22 is located between the fluid inlet 25 and the fluid outlet 26.

[0077] Figure 9 Figure 2 is a top view of a fourth embodiment of an orifice in accordance with the present application, Figure 1 Figure 3 is a cross-sectional view of the orifice of Figure 2 along the line A-A. Figure 10 Figure 4 is a top view of a fifth embodiment of an orifice in accordance with the present application, Figure 9 Figure 5 is a cross-sectional view of the orifice of Figure 4 along the line A-A. Figure 9 Figure 6 is a top view of a sixth embodiment of an orifice in accordance with the present application, Figure 10 Figure 7 is a cross-sectional view of the orifice of Figure 6 along the line A-A.

[0078] Figure 11 Figure 8 is a top view of a seventh embodiment of an orifice in accordance with the present application, Figure 1 Figure 9 is a cross-sectional view of the orifice of Figure 8 along the line A-A. Figure 12 Figure 10 is a top view of an eighth embodiment of an orifice in accordance with the present application, Figure 11 Figure 11 is a cross-sectional view of the orifice of Figure 10 along the line A-A. Figure 11 Figure 12 is a top view of a ninth embodiment of an orifice in accordance with the present application, Figure 12 Figure 13 is a cross-sectional view of the orifice of Figure 12 along the line A-A.

[0079] Figure 13 Figure 14 is a top view of a tenth embodiment of an orifice in accordance with the present application, Figure 1 Figure 15 is a cross-sectional view of the orifice of Figure 14 along the line A-A. Figure 14 Figure 16 is a top view of an eleventh embodiment of an orifice in accordance with the present application, Figure 13 Figure 17 is a cross-sectional view of the orifice of Figure 16 along the line A-A. Figure 13 Figure 18 is a top view of a twelfth embodiment of an orifice in accordance with the present application, Figure 14 Figure 19 is a cross-sectional view of the orifice of Figure 18 along the line A-A.

[0080] Figure 15 Figure 20 is a top view of a thirteenth embodiment of an orifice in accordance with the present application, Figure 1 Figure 21 is a cross-sectional view of the orifice of Figure 20 along the line A-A. Figure 16 Figure 22 is a top view of a fourteenth embodiment of an orifice in accordance with the present application, Figure 15 Figure 23 is a cross-sectional view of the orifice of Figure 22 along the line A-A. Figure 15 Figure 24 is a top view of a fifteenth embodiment of an orifice in accordance with the present application, Figure 16The illustrated throttle 17 is a porous throttle with external threads 24 disposed between 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 throttle orifice 22 is located between the fluid inlet 25 and the fluid outlet 26.

[0081] Figure 17 for Figure 1 A top view of the eighth embodiment of the throttle in the diagram. Figure 18 for Figure 17 A schematic diagram of the AA cross-section of the throttle in the diagram. Figure 17 and Figure 18 The illustrated internal thread 23 is provided in the orifice throttle valve between 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 throttle orifice 22 is located between the fluid inlet 25 and the fluid outlet 26. Internal thread 23 and external thread 24 are two common thread types; internal thread 23 refers to a thread formed on the inner surface of the hole, and external thread 24 refers to a thread formed on the outer surface of the hole. Different thread configurations allow for the selection of the throttle valve according to different application requirements to achieve optimal fluid control.

[0082] like Figure 4 , 6 As shown in Figures 12 and 14, an external thread 24 is provided at one of the fluid inlet 25 and fluid outlet 26 of the throttle 17, and a radially outwardly projecting flange is provided at the other of the fluid inlet 25 and fluid outlet 26, for example, at the end of the external thread 24, to provide a stop after the throttle 17 is engaged with other pipe fittings, ensuring that the throttle 17 does not move axially in the pipeline after installation. The outer diameter of the throttle 17 changes from the external thread 24 to the flange, for example, forming a step. In the illustrated embodiment, the end of the thread refers, for example, to an incomplete section of thread formed at the end of the effective thread length during thread machining, typically a transition area that gradually becomes shallower until it disappears. The opposite of the end of the thread is the beginning of the thread, the part where the thread begins to form. In this example, the beginning of the thread is used to guide the pipe fitting towards the helical 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. Figure 10 , 18 As shown, the fluid inlet 25 and fluid outlet 26 of the throttle 17 are provided with internal threads 23, but no external threads are provided. Therefore, the appearance of the throttle 17 can be cylindrical 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 scheme of the present application is suitable for wafer thinning process of wafer thinning equipment, and can reduce damage of water impact on the pressure sensor when the pressure in the fluid pipeline changes. According to a further optional technical scheme, in the processing process, considering that the debris and silicon powder in the fluid may damage the pressure sensor, filtering out large particles through the filter can avoid the choke valve from being blocked, at the same time, the choke valve filters out the still possible large particles and reduces the impact of water, which can prolong the service life of the pressure sensor, reduce the equipment maintenance cost, improve the reliability and stability of the equipment.

[0084] The above embodiments are only used to illustrate the present application, and are not intended to limit the present application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, all equivalent technical solutions belong to the scope of the present application, and the patent protection scope of the present application should be defined by the claims.

Claims

1. A pressure detecting apparatus for detecting a pressure change of a vacuum system of a wafer thinning apparatus, characterized by, The pressure detection device comprises a pressure sensor (16) and a pressure sensor line (19), the first end of the pressure sensor line (19) being connected to the pressure sensor (16), the second end of the pressure sensor line (19) being used to connect the fluid line (11) of the vacuum system.

2. The pressure detecting device according to claim 1, wherein The pressure sensor (16) is a diaphragm pressure sensor.

3. The pressure detecting device according to claim 1 or 2, wherein The pressure sensor (16) is connected to the first end of the pressure sensor line (19) through a restrictor (17).

4. The pressure detecting device according to claim 3, wherein A filter (18) is arranged in the pressure sensor line (19), the filter (18) being located between the second end of the pressure sensor line (19) and the restrictor (17).

5. The pressure detecting device according to claim 3, wherein The restrictor (17) has a fluid inlet (25) and a fluid outlet (26), the fluid inlet (25) and the fluid outlet (26) being communicated through a restrictor hole (22), the aperture of the restrictor hole (22) being smaller than the fluid inlet (25) and smaller than the fluid outlet (26), the restrictor hole (22) being used to regulate the flow of fluid, the fluid inlet (25) being connected to the first end of the pressure sensor line (19), the fluid outlet (26) being connected to the pressure sensor (16).

6. The pressure detecting device according to claim 5, wherein The restrictor (17) has one or more restrictor holes (22), and the restrictor holes (22) are arranged eccentrically relative to the fluid inlet (25) and the fluid outlet (26).

7. The pressure detecting device according to claim 5, wherein The restrictor (17) has a plurality of restrictor holes (22), and the plurality of restrictor holes (22) are arranged uniformly in a circumferential direction around the central axis of the restrictor (17).

8. The pressure detecting device according to claim 5, wherein An inner thread (23) and / or an outer thread (24) for connection is arranged at the fluid inlet (25) of the restrictor (17), and an inner thread (23) and / or an outer thread (24) for connection is arranged at the fluid outlet (26).

9. The pressure detecting device according to claim 5, wherein An outer thread (24) is arranged at one of the fluid inlet (25) and the fluid outlet (26) of the restrictor (17), and a radially outwardly protruding flange is arranged at the other one of the fluid inlet (25) and the fluid outlet (26).

10. The pressure detecting device according to claim 5, wherein An outer thread (24) is arranged at both the fluid inlet (25) and the fluid outlet (26) of the restrictor (17), and a radially outwardly protruding flange is arranged between the fluid inlet (25) and the fluid outlet (26).

11. A vacuum system for a wafer thinning apparatus, comprising: The vacuum system comprises the pressure detection device according to any one of claims 1 to 10, the vacuum system further comprising: A worktable (8) having a worktable vacuum area (7) for fixing a wafer (6) by vacuum; The fluid line (11) has a first end and a second end, the first end of the fluid line (11) being connected to the worktable vacuum area (7); A branch of the fluid line (11), the branch and the pressure sensor line (19) being in fluid communication with the second end of the fluid line (11) via a junction (20).

12. The vacuum system of claim 11, wherein, The branch includes a vacuum branch (15), a compressed air branch (14) and a water supply branch (13), wherein the vacuum branch (15) is used for controlling the vacuum environment of the vacuum system of the wafer thinning device, the compressed air branch (14) is used for releasing compressed air between the worktable vacuum area (7) and the wafer (6), and the water supply branch (13) is used for releasing water between the worktable vacuum area (7) and the wafer (6).

13. A wafer thinning apparatus, comprising: The wafer thinning device has the vacuum system as claimed in claim 11 or 12, and further comprises: A grinding assembly, the grinding assembly includes a grinding spindle (4) and a grinding wheel (5) mounted on the grinding spindle (4), a cooling water channel (3) is arranged at the grinding assembly, and an on-off valve (2) is arranged in the cooling water channel (3); A chuck worktable, the chuck worktable includes the worktable (8), the worktable (8) is provided with a worktable vacuum area (7) for fixing the wafer (6), the worktable is mounted on the wafer thinning device through a bearing (9), and the fluid pipeline (11) is communicated with the worktable vacuum area (7) at a first end of the fluid pipeline (11) through a rotary joint (10) and the bearing (9).

Images