Wafer carrying table and wafer thinning equipment

Abstract

The utility model provides a wafer carrying table and wafer thinning equipment, the wafer carrying table comprises a bearing piece, an air bearing, a connecting shaft, a bearing seat, a bearing, a first transmission wheel, an end cover and a driving assembly, the bearing piece is provided with a ceramic suction cup, and a to-be-machined piece is borne on the ceramic suction cup; the air bearing comprises a shell and an air spindle, the air spindle is provided with an upper part, a middle part and a lower part, the middle part is rotationally arranged in the shell, and the upper part is connected with the bearing piece; the connecting shaft extends in the vertical direction, and one end of the connecting shaft is connected with the air main shaft. The bearing seat is fixed relative to the shell, and the connecting shaft penetrates through the bearing seat; the bearing sleeve is arranged on the outer side of the bearing seat; the first transmission wheel sleeves the outer side of the bearing; the end cover is connected to the lower end of the first transmission wheel and connected with the connecting shaft. The driving assembly is located on the radial side of the first transmission wheel, is in transmission connection with the first transmission wheel and is used for driving the first transmission wheel to rotate so as to transmit the radial force to the shell.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and more particularly to a wafer stage and thinning apparatus. Background Technology

[0002] In the semiconductor manufacturing industry, wafers need to be ground, which usually requires the use of a wafer stage. It can provide a stable platform for placing the wafer, accurately position the wafer, and ensure that the wafer is in the correct position during processing to meet the requirements of high-precision processing.

[0003] In the prior art, the drive unit of the wafer stage is located on the radial side of the air spindle and is driven by a synchronous belt to drive the carrier to rotate. However, the synchronous belt pulley is directly mounted on the air spindle, which generates radial force in addition to tangential force. This radial force acts on the air spindle, which in turn causes the air spindle to be subjected to radial force, resulting in a decrease in the radial rigidity of the air spindle. This makes it impossible to guarantee the stability of the air spindle during operation and affects the wafer processing accuracy.

[0004] Meanwhile, during the operation of the air bearing, the air spindle will float up or fall as the compressed gas supplied to the air bearing enters or stops, resulting in axial displacement. Consequently, the synchronous pulley connected to the air spindle will also move axially, causing harmful friction between the synchronous belt and the synchronous pulley or a sudden increase or decrease in the tension of the synchronous belt, which reduces the stability of the transmission and the service life of the synchronous belt. Utility Model Content

[0005] This application discloses a wafer stage and a wafer grinding apparatus, which can ensure the stability of the air spindle during operation, thereby improving the wafer processing accuracy.

[0006] To achieve the above objectives, this application discloses a method comprising:

[0007] A carrier component, on which a ceramic suction cup is provided, and the workpiece to be processed is supported on the ceramic suction cup;

[0008] An air bearing, comprising a housing and an air spindle, the air spindle having an upper part, a middle part and a lower part, the middle part being rotatably disposed within the housing, and the upper part being connected to the load-bearing member;

[0009] A connecting shaft extends vertically, and one end of the connecting shaft is connected to the air main shaft;

[0010] A bearing housing is fixed relative to the housing, and the connecting shaft passes through the bearing housing;

[0011] The bearing is fitted onto the outside of the bearing housing;

[0012] The first transmission wheel is sleeved on the outside of the bearing;

[0013] An end cap is attached to the lower end of the first transmission wheel and connected to the connecting shaft;

[0014] A drive assembly is located on the radial side of the first transmission wheel and is connected to the first transmission wheel for driving the first transmission wheel to rotate.

[0015] Optionally, the drive assembly further includes a second transmission wheel, a transmission member, and a drive member. The second transmission wheel is connected to the drive member, and the transmission member is radially connected to the first transmission wheel and the second transmission wheel so as to drive the first transmission wheel to rotate when the drive member drives the second transmission wheel to rotate.

[0016] Optionally, both the first and second drive wheels are sprockets, and the transmission component is a chain connecting the first and second drive wheels; or,

[0017] Both the first and second transmission wheels are synchronous pulleys, and the transmission component is a synchronous belt connecting the first and second transmission wheels.

[0018] Optionally, the wafer stage further includes a mounting base, the bearing housing is connected to the lower surface of the mounting base, and the housing is connected to the upper surface of the mounting base.

[0019] Optionally, the end cap is provided with a first spline, and the outer peripheral surface of the connecting shaft is provided with a second spline that mates radially with the first spline along the connecting shaft.

[0020] Optionally, the wafer stage includes:

[0021] A first cooling channel is provided on the support member;

[0022] The second cooling channel is disposed on the connecting shaft, with one end of the second cooling channel connected to the first cooling channel and the other end connected to the liquid source.

[0023] Optionally, the first cooling channel includes a plurality of annular cooling channels and a plurality of first radial cooling channels. The plurality of annular cooling channels are arranged sequentially along the radial direction of the support member, and adjacent annular cooling channels are connected by at least one of the first radial cooling channels.

[0024] Optionally, the centers of the multiple annular cooling channels are all located on the axis of the support member.

[0025] Optionally, the first cooling channel further includes a second radial cooling channel, which is disposed on the outer periphery of the outermost annular cooling channel and penetrates the sidewall of the support member to form a liquid outlet.

[0026] Optionally, the diameter of the liquid outlet is smaller than the diameter of the second cooling channel.

[0027] Optionally, the wafer stage further includes a waterproof cover, which is disposed below the liquid outlet and surrounds the carrier.

[0028] Optionally, the connection point between the first cooling channel and the second cooling channel is located on the axis of the support member.

[0029] Optionally, the connecting shaft is further provided with a circulation channel, one end of which is connected to the liquid source and the other end of which is connected to the liquid outlet.

[0030] Optionally, a cooling element is provided on the circulation channel, which is used to cool the coolant flowing into the circulation channel through the outlet.

[0031] Optionally, the carrier is a ceramic component.

[0032] Optionally, the ceramic suction cup is provided with adsorption holes;

[0033] The carrier is provided with a first air channel, which is connected to the adsorption hole;

[0034] The connecting shaft is provided with a second air passage, one end of which is connected to the first air passage and the other end is connected to the negative pressure component.

[0035] This application also provides a wafer thinning apparatus, comprising:

[0036] The aforementioned wafer carrier;

[0037] A wafer grinding wheel is positioned above the wafer stage and is used to grind the workpiece to be processed, which is supported on the ceramic chuck.

[0038] Compared with the prior art, the beneficial effects of this application are as follows:

[0039] When the drive assembly drives the first transmission wheel to rotate, in addition to the tangential force that causes the first transmission wheel to rotate circumferentially, a radial force is also generated. This radial force acts directly on the first transmission wheel. After the radial force is applied to the first transmission wheel, the first transmission wheel transmits the radial force to the bearing and the bearing mounting seat in sequence. The bearing seat is fixed relative to the housing, so as to transmit this radial force to the housing or other support structures of the wafer stage as much as possible, rather than to the connecting shaft by the first transmission wheel. This is to avoid the air spindle tilting due to the radial force as much as possible, so as to ensure the stability of the air spindle during operation and improve the wafer processing accuracy. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a cross-sectional view of a wafer stage provided in an embodiment of this application;

[0042] Figure 2 This is a schematic diagram of an air bearing provided in an embodiment of this application;

[0043] Figure 3 This is a schematic diagram of the air bearing spindle tilting according to an embodiment of this application;

[0044] Figure 4 This is a schematic diagram of the first cooling channel provided in an embodiment of this application;

[0045] Figure 5 yes Figure 4 Enlarged view of point A in the middle;

[0046] Figure 6 This is a cross-sectional view of a wafer thinning apparatus provided in an embodiment of this application.

[0047] Explanation of main figure symbols

[0048] 1-Wafer stage;

[0049] 2-Wafer thinning equipment; 2a-Wafer grinding wheel;

[0050] 10-Bearing component; 11-Ceramic suction cup;

[0051] 20 - Air bearing; 21 - Housing; 22 - Air spindle;

[0052] 30 - Connecting shaft;

[0053] 40 - Bearing housing;

[0054] 50-Bearing;

[0055] 60 - First transmission wheel;

[0056] 70-End cap;

[0057] 80-Drive assembly; 81-Second transmission wheel; 82-Transmission component; 83-Drive component;

[0058] 90 - Mounting base;

[0059] 100 - First cooling channel; 101 - Annular cooling channel; 102 - First radial cooling channel; 103 - Second radial cooling channel; 104 - Liquid outlet;

[0060] 110 - Second cooling channel;

[0061] 120-Waterproof Cover;

[0062] 130 - Second airway;

[0063] 140 - Rotary joint. Detailed Implementation

[0064] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0065] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0066] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0067] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0068] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components whose specific types and structures may be the same or different, and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0069] As mentioned in the background section, in the prior art, the drive unit of the wafer stage is located on the radial side of the air spindle and is then connected to the drive via a synchronous belt. The synchronous belt pulley is directly mounted on the air spindle, which generates not only tangential force but also radial force. This radial force acts on the air spindle, which in turn causes the air spindle to be subjected to radial force, resulting in a reduction in the radial rigidity of the air spindle. This makes it impossible to guarantee the stability of the air spindle during operation, thus failing to improve the wafer processing accuracy.

[0070] To address the aforementioned issues, this application provides a wafer stage and a wafer thinning device. The wafer stage can transmit radial force to the housing of the air bearing or other support structures of the wafer stage, instead of transmitting it to the connecting shaft via the first drive wheel. This minimizes the risk of the air spindle tilting due to radial force, thereby ensuring the stability of the air spindle during operation and improving wafer processing accuracy. Furthermore, the drive mechanism for the air spindle employs a spline connection that can transmit torque and allow for relative axial displacement.

[0071] The technical solution of this application will be further described below with reference to specific embodiments and accompanying drawings.

[0072] See Figure 1This embodiment provides a wafer stage 1, which includes: a carrier 10, an air bearing 20, a connecting shaft 30, a bearing seat 40, a bearing 50, a first transmission wheel 60, an end cap 70, and a drive assembly 80. A ceramic chuck 11 is mounted on the carrier 10, and the workpiece to be processed is supported on the ceramic chuck 11. The air bearing 20 includes a housing 21 and an air spindle 22. The air spindle 22 has an upper part, a middle part, and a lower part. The middle part is rotatably disposed within the housing 21, and the upper part is connected to the carrier 10. Shaft 30 extends vertically, and one end of connecting shaft 30 is connected to air main shaft 22; bearing seat 40 is fixed relative to housing 21, and connecting shaft 30 passes through bearing seat 40; bearing 50 is sleeved on the outside of bearing seat 40; first transmission wheel 60 is sleeved on the outside of bearing 50; end cover 70 is connected to the lower end of first transmission wheel 60 and connected to connecting shaft 30; drive assembly 80 is located on the radial side of first transmission wheel 60 and is connected to first transmission wheel 60 for driving first transmission wheel 60 to rotate.

[0073] The transmission connection between the drive component 80 and the first transmission wheel 60 can be a belt drive, a gear drive, etc., and is not limited here.

[0074] It should be noted that the air bearing 20 is a bearing that uses gas (usually air) as a lubricating medium. Its working principle is based on the hydrodynamics or hydrostatic principle of gas. A very thin air film is formed between the air spindle 22 and the housing 21. This air film separates the rotating air spindle 22 from the stationary housing 21, allowing the air spindle 22 to rotate in a state of almost no friction.

[0075] Furthermore, this embodiment uses a wafer as an example to illustrate the process, where the vertical direction is described above. Figure 1 The direction indicated by the middle arrow Y is the radial direction of the first transmission wheel 60. Figure 1 The direction indicated by the middle arrow X.

[0076] When the drive assembly 80 drives the first transmission wheel 60 to rotate, the first transmission wheel 60 drives the end cover 70 to rotate. The end cover 70 is connected to the lower end of the connecting shaft 30, which can drive the connecting shaft 30 to move synchronously, so that the connecting shaft 30 can transmit the rotational motion and torque of the first transmission wheel 60 to the air spindle 22. After receiving the power from the connecting shaft 30, the air spindle 22 rotates at high speed in the housing 21 of the air bearing 20. Since the upper end of the air spindle 22 is connected to the carrier 10, the carrier 10 rotates along with the rotation of the air spindle 22, so as to drive the wafers carried on the carrier 10 to rotate.

[0077] When the drive assembly 80 drives the first transmission wheel 60 to rotate, in addition to the tangential force that drives the first transmission wheel 60 to rotate circumferentially, a radial force is also generated. This radial force acts directly on the first transmission wheel 60. After the radial force is applied to the first transmission wheel 60, the first transmission wheel 60 transmits the radial force sequentially to the bearing 50 and the bearing mounting seat 90. The bearing seat 40 is fixed relative to the housing 21, thereby transmitting this radial force as much as possible to the housing 21 or other support structures of the wafer stage 1, rather than through the first transmission wheel 60 to the connecting shaft 30, so as to avoid the air spindle 22 being tilted by the radial force (see...). Figure 2 and Figure 3 This ensures the stability of the air spindle during operation, thereby improving the precision of wafer processing.

[0078] Furthermore, the end cap 70 is connected to the lower end of the first transmission wheel 60. When the first transmission wheel 60 is subjected to radial force, it is first transmitted to the bearing mounting seat 90 through the bearing 50, which can minimize the radial force acting on the end cap 70 and being transmitted to the connecting shaft 30.

[0079] Alternatively, the bearing 50 can be a ball bearing, consisting of an inner ring, an outer ring, and multiple balls sandwiched between them, or a roller bearing, with inner and outer rings paired with cylindrical rollers. Taking a ball bearing as an example, when the radial force is initially transmitted from the first drive wheel 60 to the bearing 50, the radial force, which was originally rigidly transmitted, can be transformed into a force transmission form of rolling friction through the balls. When the bearing 50 is pushed by the force to roll the balls, each ball will bear a certain component of the radial force. By the free rolling of the balls between the inner and outer ring tracks, the concentrated radial force is decomposed into multiple smaller components, which are evenly distributed along their respective tracks and then transmitted to the bearing housing 40. When the radial force direction is deviated, the balls can quickly gather towards the side with the greater force. By adjusting the air gap and contact angle through rolling displacement, the radial force is smoothly converted, thereby minimizing the transmission of radial force to the air spindle 22, so as to improve the smoothness of the wafer stage 1 when driving the wafer to rotate and the wafer processing accuracy.

[0080] Furthermore, the air spindle 22 is located inside the housing 21, and there is an air film between the air spindle 22 and the housing 21. The air film is a crucial buffer "medium". The air film is maintained by the introduced high-pressure gas and has specific stiffness and stability. If a part of the radial force still reaches the air spindle 22, the air film will quickly adjust the internal air pressure distribution according to the direction and magnitude of the radial force, increase the air pressure in the local area to resist the external force, disperse and absorb part of the radial force, reduce the actual force on the air spindle 22, and thus avoid the air spindle 22 from being subjected to radial force as much as possible.

[0081] In one possible embodiment, see Figure 1The drive assembly 80 also includes a second transmission wheel 81, a transmission member 82, and a drive member 83. The second transmission wheel 81 is connected to the drive member 83. The transmission member 82 is radially connected to the first transmission wheel 60 and the second transmission wheel 81 so as to drive the first transmission wheel 60 to rotate when the drive member 83 drives the second transmission wheel 81 to rotate.

[0082] Thus, the power of the drive component 83 is first transmitted to the second transmission wheel 81, and then transferred to the first transmission wheel 60 via the transmission component 82. The transmission component 82 connects the two along the radial direction of the first transmission wheel 60, changing the force transmission path and buffering and dispersing the radial force. For example, in a gear transmission scenario, this intermediate link can decompose and balance the meshing force, avoid a sudden increase in radial force in a certain direction, maintain the smooth rotation of the first transmission wheel 60, and prevent damage to components such as the connecting shaft 30 and bearing 50 due to uneven radial force. Furthermore, the drive component 80 can flexibly adjust the torque output by combining the second transmission wheel 81 and the transmission component 82. By adjusting the specifications of the transmission component 82 (such as the chain pitch and belt width) and the transmission ratio between the second transmission wheel 81 and the first transmission wheel 60, the torque required by the bearing component 10 in real time can be precisely matched.

[0083] In one possible embodiment, the first drive wheel 60 and the second drive wheel 81 are both sprockets, and the transmission component 82 is a chain connecting the first drive wheel 60 and the second drive wheel 81.

[0084] The transmission method of the sprocket and chain has a stable and precise transmission ratio. The chain links on the chain mesh tightly with the teeth of the sprocket. When the driving component 83 drives the second transmission wheel 81 to rotate and drives the first transmission wheel 60 through the chain, the transmission ratio hardly deviates with each revolution, ensuring the rotational accuracy of the bearing component 10.

[0085] In one possible embodiment, the first transmission wheel 60 and the second transmission wheel 81 are both synchronous pulleys, and the transmission component 82 is a synchronous belt connecting the first transmission wheel 60 and the second transmission wheel 81.

[0086] The timing belt is made of flexible and elastic material, which has shock absorption and buffering capabilities. When the drive unit 83 starts, accelerates, decelerates or stops, it may generate impact and vibration. The timing belt can absorb and resolve these force fluctuations and maintain the smooth and continuous rotation of the first drive pulley 60.

[0087] In one possible embodiment, see Figure 1 The wafer stage 1 also includes a mounting base 90, a bearing housing 40 connected to the lower surface of the mounting base 90, and a housing 21 connected to the upper surface of the mounting base 90.

[0088] Therefore, the mounting base 90 provides a mounting reference for the bearing housing 40 and the housing 21. The bearing housing 40 is connected to the lower surface of the mounting base 90, and the housing 21 is connected to the upper surface of the mounting base 90. The contact area between the bearing housing 40 and the housing 21 and the mounting base 90 is relatively large. When the radial force is transmitted from the bearing housing 40 to the housing 21, the radial force will not be concentrated at a few small points, but will be evenly distributed across the entire contact plane. This can effectively avoid the deformation and wear of the mounting base 90 caused by excessive local stress, maintain a stable relative position between the components, and ensure the long-term stable operation of the wafer stage 1.

[0089] In one possible embodiment, the end cap 70 is provided with a first spline, and the outer peripheral surface of the connecting shaft 30 is provided with a second spline that mates radially with the first spline along the connecting shaft 30.

[0090] The first spline can be composed of multiple keyways, and the second spline can be composed of key teeth that radially engage with the multiple keyways. Both have precise geometry and uniform distribution. During the process where the drive assembly 80 drives the first transmission wheel 60 to rotate, thereby transmitting force to the connecting shaft 30, the first and second splines ensure that torque is accurately transmitted in a specific direction and angle. Simultaneously, during the lifting and lowering of the air spindle 22, the first and second splines undergo relative axial displacement, avoiding any impact on the transmission of the drive assembly 80. Compared to other relatively loose or slip-prone connection methods, the first spline and the second spline... The double spline connection allows the connecting shaft 30 to receive a stable and precise torque, ensuring that the bearing component 10 can achieve stable and precise rotation. Furthermore, the first and second splines can not only transmit torque but also have a certain ability to bear radial force. When the first transmission wheel 60 rotates and generates radial force, it can reasonably distribute part of the radial force to the mating surfaces of each key tooth and keyway. Compared with the connection structure with a single contact surface, this multi-contact bearing method can more effectively disperse the radial force, avoid bending or deformation of the connecting shaft 30 due to excessive local stress, and maintain the stability of the connecting shaft 30 in the radial direction.

[0091] It should be noted that the second spline can be integrally formed on the outer peripheral surface of the connecting shaft 30, or an additional part with a second spline can be provided and fixedly fitted onto the outer peripheral surface of the connecting shaft. No limitation is made here.

[0092] In one possible embodiment, see Figure 1 and Figure 4 The wafer stage 1 includes: a first cooling channel 100 and a second cooling channel 110. The first cooling channel 100 is disposed on the support member 10; the second cooling channel 110 is disposed on the connecting shaft 30. One end of the second cooling channel 110 is connected to the first cooling channel 100 and the other end is connected to the liquid source.

[0093] The coolant originates from the liquid source and enters the second cooling channel 110 located on the connecting shaft 30 through pipes or other connections. As the coolant flows through the second cooling channel 110, since one end of the second cooling channel 110 is connected to the first cooling channel 100 located on the support member 10, the coolant flows into the first cooling channel 100 along the connection path. During power transmission, the connecting shaft 30 generates heat due to friction with other components and its own rotation. The coolant in the second cooling channel 110 can directly absorb this heat, effectively reducing the temperature of the connecting shaft 30 and preventing it from expanding due to overheating. Deformation can affect the fit accuracy of the connecting shaft 30 with other components (such as bearing 50). Maintaining the normal operating temperature of the connecting shaft 30 helps maintain the stability and accuracy of power transmission and ensures the stable rotation of the carrier 10. During operation, the carrier 10 may generate heat due to friction and heat conduction during processing, as it holds wafers and other processing objects. The coolant in the first cooling channel 100 can remove this heat in time, keeping the carrier 10 at a suitable temperature. By cooling the connecting shaft 30 and the carrier 10, the impact of thermal deformation of the connecting shaft 30 and the air spindle 22 on the accuracy of the wafer stage 1 can be reduced.

[0094] The coolant can be any form of coolant, such as water, deionized water, ethylene glycol-water coolant, etc., and there are no restrictions here.

[0095] In one possible embodiment, see Figure 4 The first cooling channel 100 includes a plurality of annular cooling channels 101 and a plurality of first radial cooling channels 102. The plurality of annular cooling channels 101 are arranged sequentially along the radial direction of the support member 10, and adjacent annular cooling channels 101 are connected by at least one first radial cooling channel 102.

[0096] Multiple annular cooling channels 101 are arranged sequentially along the radial direction of the support member 10. This layout enables the coolant to be evenly distributed in the circumferential direction of the support member 10. Each annular cooling channel 101 can absorb the heat in its circumferential area. When the support member 10 generates heat during operation, the annular cooling channels 101 can effectively carry away the heat in the circumferential direction, avoiding local overheating. Adjacent annular cooling channels 101 are connected by at least one first radial cooling channel 102, which allows the coolant to flow in the radial direction. In this way, the coolant can flow across the entire plane of the support member 10, fully absorbing heat in both the circumferential and radial directions. For example, the heat generated in the central area of ​​the support member 10 can be transferred to the outer annular cooling channels 101 through the radial cooling channels and then carried away by the coolant, thereby achieving uniform cooling of the entire support member 10.

[0097] In addition, the presence of multiple annular cooling channels 101 and the first radial cooling channel 102 increases the contact area between the coolant and the carrier 10, meaning that more heat can be transferred from the carrier 10 to the coolant, thereby improving cooling efficiency.

[0098] Of course, the first cooling channel 100 is not limited to the above form. For example, the first cooling channel 100 can also be a spiral cooling channel, in which the cooling channel extends from the center of the support member 10 to the periphery in a spiral shape, or converges from the periphery to the center; or a grid-shaped cooling channel, in which the cooling channel forms a crisscross grid shape inside the support member 10, and the coolant can enter from a node or edge of the grid, flow through the crisscross channels in the support member 10, and finally flow out from the corresponding outlet.

[0099] In one possible embodiment, see Figure 4 The centers of the multiple annular cooling channels 101 are all located on the axis of the support member 10.

[0100] This results in a symmetrical distribution of the coolant flow path with the axis of the support member 10 as the center of symmetry, making the cooling effect of the coolant more uniform.

[0101] For example, in semiconductor wafer processing, the entire wafer surface must maintain a uniform temperature environment to avoid uneven thermal expansion and contraction of the wafer material due to temperature differences, which would affect processing accuracy and product quality. This symmetrical annular cooling channel 101 design can well meet this requirement.

[0102] In one possible embodiment, see Figure 4 and Figure 5 The first cooling channel 100 also includes a second radial cooling channel 103, which is disposed on the outer periphery of the outermost annular cooling channel 101 and penetrates the side wall of the support member 10 to form a liquid outlet 104.

[0103] The second radial cooling channel 103 is located on the outer periphery of the outermost annular cooling channel 101 and penetrates the side wall of the support member 10 to form an outlet 104, providing a direct and smooth discharge channel for the coolant. After the coolant flows through multiple annular cooling channels 101 and the first radial cooling channel 102 connected to them, and completes the absorption of heat from the support member 10, it can flow out of the support member 10 in an orderly manner through this specially designed outlet 104. For example, when the coolant circulates and continuously heats up within the entire first cooling channel 100 system, the outlet 104 can ensure its timely discharge, preventing the coolant from accumulating in the channel and maintaining the normal operation of the cooling system.

[0104] In one possible embodiment, see Figure 5 The diameter of the liquid outlet 104 is smaller than the diameter of the second cooling channel 110.

[0105] The smaller diameter of the outlet 104 will reduce the flow cross-sectional area of ​​the coolant when it flows out of the carrier 10. Under the condition of a constant flow rate (determined by the liquid supply and the circulation characteristics of the entire cooling system), the smaller cross-sectional area will lead to an increase in flow velocity. This allows the coolant to absorb heat more fully after passing through the cooling channels inside the carrier 10, and then be discharged from the outlet 104 at a faster speed, so that the heat can be carried away more promptly.

[0106] In one possible embodiment, see Figure 1 The wafer stage 1 also includes a waterproof cover 120, which is located below the liquid outlet 104 and surrounds the carrier 10.

[0107] The waterproof cover 120 is located below the liquid outlet 104 and surrounds the carrier 10, which can effectively catch the coolant that may splash out and prevent the coolant and grinding fluid from dripping onto other parts of the wafer stage 1 and causing damage to other parts of the wafer stage 1.

[0108] In one possible embodiment, see Figure 1 The connection point between the first cooling channel 100 and the second cooling channel 110 is located on the axis of the support member 10.

[0109] This allows the coolant to diffuse symmetrically outwards from the axis of the support member 10 when it enters the first cooling channel 100 from the second cooling channel 110. This helps to evenly distribute the coolant into each annular cooling channel 101, thereby ensuring that the heat in each area is carried away evenly and improving cooling efficiency.

[0110] In one possible embodiment, a circulation channel is also provided inside the connecting shaft 30, with one end of the circulation channel connected to the liquid source and the other end connected to the liquid outlet 104.

[0111] Therefore, this continuous and closed-loop circulation system ensures that the coolant can continuously perform its cooling function, thereby reducing coolant consumption and lowering living costs.

[0112] In one possible embodiment, a cooling element is provided on the circulation channel for cooling the coolant flowing into the circulation channel through the outlet 104.

[0113] When the coolant flows into the circulation channel from the outlet 104 of the carrier 10, it has already absorbed a large amount of heat from the carrier 10 and the connecting shaft 30, and its temperature is relatively high. The cooling component is located here, which can quickly cool the incoming high-temperature coolant and reduce its temperature. After cooling, the coolant can re-enter the cooling channel of the connecting shaft 30 and the carrier 10 at a lower temperature, regain its good heat absorption capacity, and continue to effectively remove the heat generated by the key components, thereby maintaining the efficient and stable cooling effect of the entire cooling system and ensuring that all components of the wafer stage 1 are always within the appropriate operating temperature range.

[0114] In one possible embodiment, see Figure 1 The ceramic suction cup 11 is provided with an adsorption hole; the carrier 10 is provided with a first air passage, which is connected to the adsorption hole; the connecting shaft 30 is provided with a second air passage 130, one end of which is connected to the first air passage and the other end is connected to the negative pressure component.

[0115] The adsorption holes on the ceramic suction cup 11 are connected to the negative pressure component through the first air channel and the second air channel 130. When the negative pressure component is working, a negative pressure environment is formed at the adsorption holes. When the wafer is placed on the carrier 10, this negative pressure can tightly adsorb the wafer and fix it firmly on the ceramic suction cup, preventing the wafer from shifting position during the rotation, movement or processing of the carrier 10.

[0116] In one possible embodiment, see Figure 1 The wafer stage 1 also includes a rotary joint 140, which is connected to the lower end of the connecting shaft 30. The rotary joint 140 is used to achieve dynamic connection and media transmission, maintaining a continuous fluid channel. For example, in the case of media such as coolant, lubricant, and gas (such as the gas required by the air bearing 20, adsorbed gas), the rotary joint 140 can maintain the smooth flow of media transmission even under the dynamic condition of continuous rotation of the connecting shaft 30. For example, when coolant needs to be transported from an external liquid source to the cooling channel set in the connecting shaft 30, the rotary joint 140 allows the coolant to pass smoothly. Even if the connecting shaft 30 is in a high-speed rotation state, there will be no interruption of media transmission, ensuring that cooling, lubrication and other functions can be continuously realized.

[0117] See Figure 6 This application also provides a wafer thinning device 2, including a wafer stage 1 and a wafer grinding wheel 2a. The wafer grinding wheel 2a is disposed above the wafer stage 1 and is used to grind the workpiece to be processed, which is supported on a ceramic chuck 11.

[0118] The wafer stage 1 can be the wafer stage 1 in any of the above embodiments.

[0119] In addition, the wafer thinning device 2 in this application embodiment can have the same structure as the wafer thinning device 2 in the above embodiment and can bring the same or similar beneficial effects. For details, please refer to the description in the above embodiment. This application embodiment will not be repeated here.

[0120] The above embodiments are only used to illustrate the technical solutions of the wafer stage and wafer thinning equipment of this application, and are not intended to limit them. Although the wafer stage and wafer thinning equipment of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A wafer carrier, characterized in that, The wafer stage includes: A carrier component, on which a ceramic suction cup is provided, and the workpiece to be processed is supported on the ceramic suction cup; An air bearing, comprising a housing and an air spindle, the air spindle having an upper part, a middle part and a lower part, the middle part being rotatably disposed within the housing, and the upper part being connected to the load-bearing member; A connecting shaft extends vertically, and one end of the connecting shaft is connected to the air main shaft; A bearing housing is fixed relative to the housing, and the connecting shaft passes through the bearing housing; The bearing is fitted onto the outside of the bearing housing; The first transmission wheel is sleeved on the outside of the bearing; An end cap is attached to the lower end of the first transmission wheel and connected to the connecting shaft; A drive assembly is located on the radial side of the first transmission wheel and is connected to the first transmission wheel for driving the first transmission wheel to rotate.

2. The wafer stage of claim 1, wherein, The drive assembly further includes a second transmission wheel, a transmission component, and a drive component. The second transmission wheel is connected to the drive component, and the transmission component is radially connected to the first transmission wheel and the second transmission wheel so as to drive the first transmission wheel to rotate when the drive component drives the second transmission wheel to rotate.

3. The wafer stage of claim 1, wherein, The wafer stage also includes a mounting base, the bearing housing is connected to the lower surface of the mounting base, and the housing is connected to the upper surface of the mounting base.

4. The wafer stage of claim 1, wherein, The end cap is provided with a first spline, and the outer circumferential surface of the connecting shaft is provided with a second spline that mates radially with the first spline along the connecting shaft.

5. The wafer stage of claim 1, wherein, The wafer stage includes: A first cooling channel is provided on the support member; The second cooling channel is disposed on the connecting shaft, with one end of the second cooling channel connected to the first cooling channel and the other end connected to the liquid source.

6. The wafer stage of claim 5, wherein, The first cooling channel includes multiple annular cooling channels and multiple first radial cooling channels. The multiple annular cooling channels are arranged sequentially along the radial direction of the support member, and adjacent annular cooling channels are connected by at least one first radial cooling channel.

7. The wafer stage of claim 6, wherein, The centers of the multiple annular cooling channels are all located on the axis of the support component.

8. The wafer stage according to claim 6, characterized in that, The first cooling channel further includes a second radial cooling channel, which is disposed on the outer periphery of the outermost annular cooling channel and penetrates the side wall of the support member to form a liquid outlet.

9. The wafer stage of claim 8, wherein, The wafer stage also includes a waterproof cover, which is disposed below the liquid outlet and surrounds the carrier.

10. A wafer thinning apparatus, comprising: include: The wafer stage according to any one of claims 1-9; A wafer grinding wheel is positioned above the wafer stage and is used to grind the workpiece to be processed, which is supported on the ceramic chuck.

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