Wafer adsorption device

Abstract

The utility model provides a wafer adsorption device which comprises a fixed seat, a plurality of vacuum chuck assemblies are distributed on the fixed seat, and the vacuum chuck assemblies are used for adsorbing and fixing wafers; the vacuum suction cup assembly comprises a supporting mechanism, a vacuum suction cup body, a vacuum suction cup body and a vacuum suction cup body, the vacuum suction cup is connected to one end, deviating from the fixed seat, of the supporting mechanism through a rotary connecting mechanism, an included angle between the axis of the vacuum suction cup and the axis of the supporting mechanism is adjustable, and the vacuum suction cup is used for adsorbing the back surface of a wafer through negative pressure. According to the wafer adsorption device of the utility model, a plurality of vacuum chucks are combined to perform vacuum adsorption on the wafer, so that the problem that the wafer cannot be fixed by the vacuum chucks due to dirty wafer backs and warping of the wafer in the prior art can be solved.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor processing technology, and in particular to a wafer adsorption device. Background Technology

[0002] Vacuum chucks are commonly used inside various semiconductor devices to hold wafers in place. During operation, these chucks only contact the back of the wafer, eliminating the need for additional pins to support or restrict the wafer edges, thus preventing interference with the processing on the front side. Furthermore, they enable rapid adsorption and release, significantly improving production efficiency on automated production lines, reducing workpiece loading and unloading time, and facilitating quick process changes.

[0003] The vacuum suction cups currently used on the machine are integrated suction cups (as shown in the attached image). Figure 1 As shown in the diagram, its structure involves multiple pores on the vacuum chuck 30a to adsorb the wafer 70. However, this type of vacuum chuck has very high requirements for wafer warpage (Bow value) and back-side cleanliness. If the wafer 70 warpage is too high (e.g., ...), ... Figure 1 (As shown) or if the back of the wafer is dirty, the vacuum chuck will be unable to pick up the wafer. Utility Model Content

[0004] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a wafer adsorption device to solve the problem that vacuum chucks cannot adsorb wafers when the wafer warpage is too high or the back of the wafer is dirty.

[0005] To achieve the above objectives, this utility model provides a wafer adsorption device, including a fixed base on which multiple vacuum suction cup assemblies are arranged. The vacuum suction cup assemblies are used to adsorb and fix wafers. Each vacuum suction cup assembly includes: a support mechanism connected to the fixed base; and a vacuum suction cup connected to the end of the support mechanism away from the fixed base via a rotating connection mechanism. The angle between the axis of the vacuum suction cup and the axis of the support mechanism is adjustable. The vacuum suction cup is used to adsorb the back side of the wafer through negative pressure.

[0006] The beneficial effects are as follows: The structure of multiple vacuum chucks combined to vacuum-adhere the wafer has the advantage that when the adsorption is unstable due to dirt on a certain part of the wafer back, the other vacuum chucks in the combination can still maintain stable adsorption of the wafer, thus overcoming the problem in the prior art that the wafer cannot be fixed by the vacuum chuck due to dirt on the wafer back; Furthermore, the vacuum chuck is connected to the support mechanism through a rotating connection mechanism, which realizes the self-adjustment of the vacuum chuck to better fit the wafer, thereby obtaining a better vacuum adsorption effect.

[0007] Furthermore, the support mechanism includes a support rod with a first gas flow channel inside; the first gas flow channel is connected to the pumping device; the rotating connection mechanism includes a second gas flow channel, which is connected to the first gas flow channel and the vacuum suction cup. The beneficial effect is that by respectively arranging the first and second gas flow channels for providing vacuum suction force in the support rod and the rotating connection mechanism, the structural compactness of the wafer adsorption device is effectively improved, avoiding the extra space occupied by external vacuum pipelines and the interference problems between components caused by external vacuum pipelines.

[0008] Furthermore, the rotating connection mechanism includes a first connector and a second connector. The first connector is connected to the support rod, and the second connector is connected to the vacuum chuck. The first and second connectors are rotatably connected via a spherical joint. The beneficial effect is that the use of the spherical joint allows the second connector to achieve multiple degrees of freedom of movement, greatly improving the movement flexibility of the vacuum chuck. When the vacuum chuck contacts a warped wafer, it can adaptively adjust its posture under the pressure of the wafer to better conform to the wafer backing.

[0009] Preferably, the first connector has a first channel, and the second connector has a second channel, with the first channel and the second channel communicating to form the second gas flow channel. The advantage is that this design allows the second connector to maintain its flexibility while keeping the vacuum path unobstructed.

[0010] Preferably, it also includes a lifting device; the bottom end of the support mechanism is connected to the fixed base through the lifting device, and reciprocates in a direction perpendicular to the top surface of the fixed base under the drive of the lifting device. The beneficial effect is that by setting the lifting device, it is convenient to adjust the support height of the support mechanism and the vacuum chuck, thereby ensuring that each vacuum chuck maintains contact pressure with the wafer, facilitating the adhesion and adsorption of the vacuum chuck to the wafer.

[0011] Preferably, the support mechanism is equipped with a pressure sensor, which detects the pressure on the support mechanism and transmits the pressure data to the control system of the lifting device. The beneficial effect is that, through the cooperation of the pressure sensor and the lifting device, the height of the vacuum chuck support can be quickly adjusted, thereby ensuring that each vacuum chuck maintains a balanced contact pressure with the wafer, facilitating the adhesion and adsorption of the vacuum chuck to the wafer.

[0012] Preferably, the support mechanism includes a first support rod and a second support rod; the pressure sensor is connected between the first support rod and the second support rod, and bears the pressure of the first support rod and the compressive force of the second support rod.

[0013] Preferably, the vacuum suction cup has multiple adsorption holes on its surface, and the multiple adsorption holes are evenly distributed on the surface of the vacuum suction cup.

[0014] Preferably, N support mechanisms are arranged at equal intervals along the circumference of the fixed base to form a support group, where N is a positive integer greater than or equal to 1.

[0015] Preferably, there are multiple support groups, and the multiple support groups are coaxially arranged on the fixed base.

[0016] The beneficial effects of this utility model are as follows: The wafer adsorption device of this utility model adopts a structure of multiple vacuum suction cups combined to perform vacuum adsorption on the wafer. Its advantage is that when the adsorption is unstable due to dirt on a certain part of the wafer back, the other vacuum suction cups in the vacuum suction cup combination can still maintain stable adsorption on the wafer, thus overcoming the problem in the prior art that the wafer cannot be fixed by the vacuum suction cups due to dirt on the wafer back. The vacuum suction cups are connected to the support mechanism through a rotating connection mechanism, realizing the adaptive adjustment of the vacuum suction cups to better fit the wafer, thereby obtaining a better vacuum adsorption effect. By setting pressure sensors on the support mechanisms of different vacuum suction cups, the support pressure of a single vacuum suction cup is obtained, and the support height of the vacuum suction cups is quickly adjusted according to the support pressure, thereby ensuring that each vacuum suction cup and the wafer maintain a balanced contact pressure, which facilitates the bonding and adsorption of the vacuum suction cups and the wafer. Attached Figure Description

[0017] Figure 1 The invention demonstrates a vacuum chuck structure disclosed in the prior art and its mating state with a warped wafer;

[0018] Figure 2 This is a schematic diagram of the overall structure of the wafer adsorption device and its relationship with the wafer in an embodiment of this utility model.

[0019] Figure 3 This is a schematic diagram of the overall structure of the vacuum suction cup assembly in an embodiment of this utility model;

[0020] Figure 4 This is a schematic diagram of the rotating connection mechanism in an embodiment of the present invention (posture 1).

[0021] Figure 5 This is a schematic diagram of the rotating connection mechanism in an embodiment of the present invention (posture two).

[0022] Figure 6 This is a schematic diagram of the rotating connection mechanism in an embodiment of the present invention (posture three).

[0023] Figure 7This is a schematic diagram showing the layout of multiple adsorption holes on the surface of the vacuum suction cup in an embodiment of this utility model.

[0024] Figure 8 This is a schematic diagram showing the correspondence between the layout structure of multiple vacuum suction cup components of the wafer adsorption device according to an embodiment of the present invention and the wafer.

[0025] Figure label:

[0026] 10-Fixed base;

[0027] 200 - Vacuum suction cup assembly; 20 - Support mechanism; 21 - Support rod; 22 - First axis; 23 - First gas flow channel; 24 - First support rod body; 25 - Second support rod body;

[0028] 30 - Vacuum chuck; 30a - Vacuum chuck; 31 - Second axis; 32 - Adsorption hole;

[0029] 40 - Rotary connecting mechanism; 41 - Second gas flow channel; 42 - First connector; 421 - First connector body; 422 - Cover plate; 43 - Second connector; 44 - First channel; 45 - Second channel;

[0030] 50 - Lifting device;

[0031] 60 - Pressure sensor;

[0032] 70-Wafer. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this utility model pertains. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects. Unless otherwise specified, the term "connection" as used herein can refer to a direct connection or an indirect connection, i.e., a connection through an intermediate object.

[0034] Please see Figure 2 and Figure 3This utility model provides a wafer adsorption device, including a fixed base 10, on which a plurality of vacuum suction cup assemblies 200 are arranged, the vacuum suction cup assemblies 200 being used to adsorb and fix the wafer; when in use, the wafer adsorption device is installed on the rotating table of the wafer chuck and rotates synchronously with the rotating table.

[0035] The vacuum suction cup assembly 200 includes: a support mechanism 20 and a vacuum suction cup 30;

[0036] The support mechanism 20 is connected to the fixed base 10; the vacuum chuck is connected to the end of the support mechanism 20 away from the fixed base via a rotating connecting mechanism 40, and the angle between the axis of the vacuum chuck 30 and the axis of the support mechanism is adjustable. The vacuum chuck is used to adsorb the back side of the wafer by negative pressure. Specifically, the support mechanism 20 has a first axis 22, and the vacuum chuck 30 has a second axis 31. When in contact with a warped surface on the wafer, the vacuum chuck 30 can deflect relative to the support mechanism under the pressure of the wafer, so that the first axis 22 and the second axis 31 form an angle with each other, thereby making the vacuum chuck 30 fit against the position on the wafer corresponding to the vacuum chuck 30.

[0037] In this embodiment, a structure consisting of multiple vacuum chucks 30 is used to vacuum-adsorb the wafer. Its advantage lies in that when the adsorption becomes unstable at a certain point on the back of the wafer due to dirt, the other vacuum chucks 30 in the assembly can still maintain stable adsorption of the wafer. This overcomes the problem in the prior art where the wafer cannot be fixed by the vacuum chucks 30 due to dirt on the back of the wafer (e.g., ...). Figure 1 (As shown); Furthermore, the vacuum chuck 30 is connected to the support mechanism via the rotating connection mechanism 40, which enables the vacuum chuck 30 to self-adjust to better fit the wafer 70, thereby achieving a better vacuum adsorption effect.

[0038] Please see Figure 3 In some embodiments, the support mechanism includes a support rod 21, which has a first gas flow channel 23 inside. The first gas flow channel 23 is connected to a vacuum pump (not shown). The rotating connection mechanism 40 includes a second gas flow channel 41, which is connected to the first gas flow channel 23 and to a vacuum suction cup 30. A vacuum chamber is provided inside the rotary table, and the first gas flow channel 23 is connected to the vacuum chamber. The vacuum chamber is connected to a vacuum pumping system, which is used to maintain the vacuum level of the vacuum chamber. In this embodiment, by respectively arranging the first gas flow channel 23 and the second gas flow channel 41 for providing vacuum adsorption force in the support rod 21 and the rotating connection mechanism 40, the structural compactness of the wafer adsorption device is effectively improved, avoiding the extra space occupied by external vacuum pipelines and the interference problems between components caused by external vacuum pipelines.

[0039] Please see Figure 4 and Figure 5 In some embodiments, the rotating connection mechanism 40 includes a first connector 42 and a second connector 43. The first connector 42 is connected to the support rod 21, and the second connector 43 is connected to the vacuum chuck 30. The first connector 42 and the second connector 43 are rotatably connected by a spherical pair. Specifically, the first connector 42 has a ball socket, and the second connector 43 has a ball head. The ball head and the ball socket cooperate to form a spherical pair. In this embodiment, the use of the spherical pair allows the second connector 43 to achieve multiple degrees of freedom of movement, greatly improving the movement flexibility of the vacuum chuck 30. When the vacuum chuck 30 contacts a warped wafer, the vacuum chuck 30 can adaptively adjust its posture under the pressure of the wafer to better fit the back of the wafer. Specifically, the vacuum chuck 30 can flip under the force of the wafer's own weight. At this time, the second axis 31 of the vacuum chuck 30 and the first axis 22 of the support rod 21 form an angle, thereby making the disk surface of the vacuum chuck 30 face the back of the wafer to obtain a better fitting angle and achieve a better vacuum adsorption effect. Figure 4 and Figure 5 Two orientations in which the second connector 43 is deflected relative to the first connector 42 are illustrated by way of example.

[0040] Please see Figure 4 and Figure 5 In some embodiments, the first connector 42 has a first channel 44, and the second connector 43 has a second channel 45, with the first channel 44 and the second channel 45 communicating to form the second gas flow channel 41. Furthermore, the first channel 44 and the second channel 45 are configured such that when the second connector 43 deflects to its limit angle, the second channel 45 remains connected to the first channel 44. Figure 4 and Figure 5 The illustrations demonstrate two possible orientations of the second connector 43 relative to the first connector 42 when it is deflected to its limit angle. In both orientations, the end of the second channel 45 that engages and communicates with the first channel 44 is fully inserted into the first channel 44. This design allows the second connector 43 to maintain its flexibility while keeping the vacuum passage unobstructed.

[0041] In some embodiments, the first connector 42 is threadedly connected to the support rod 21, and the second connector 43 is integrally formed with the vacuum suction cup 30. The vacuum suction cup 30 with the second connector 43 can be processed by 3D printing technology.

[0042] Please see Figure 6In other embodiments, the first connector 42 is threadedly connected to the support rod 21, and the second connector 43 is threadedly connected to the vacuum suction cup 30. Furthermore, to facilitate the assembly of the first connector 42 and the second connector 43, the first connector is designed as a split unit, comprising a first connector body 421 and a cover plate 422, which is bolted to the first connector body 421. When assembling the first connector 42 and the second connector 43, the cover plate 422 is first removed from the first connector body 421, then the ball head of the second connector 43 is connected to the ball socket of the first connector body, and finally the cover plate 422 is assembled.

[0043] Please refer to it again. Figure 3 In some embodiments, the wafer adsorption device further includes a lifting device 50; the bottom end of the support mechanism is connected to the fixed base 10 through the lifting device 50, and reciprocates in a direction perpendicular to the top surface of the fixed base 10 under the drive of the lifting device 50. In this embodiment, the lifting device 50 is a telescopic cylinder, and the lower end of the support rod 21 is fixedly connected to the telescopic rod of the telescopic cylinder.

[0044] In some embodiments, the lifting device 50 is a screw and nut type lifting device 50, which is well known to those skilled in the art and will not be described in detail here.

[0045] Please see Figure 3 In some embodiments, a pressure sensor 60 is provided on the support mechanism. The pressure sensor 60 is used to detect the pressure on the support mechanism and transmit the pressure data to the control system of the lifting device 50. After acquiring the pressure data of the support mechanism, the pressure sensor 60 transmits the pressure data to the control system of the lifting device 50. The control system first calculates the average pressure data corresponding to all vacuum suction cups 30, controls the vacuum suction cups 30 with pressure data greater than the average value to stop rising, and controls the vacuum suction cups 30 with pressure data lower than the average value to rise by 0.1 mm. Then, the above control action is repeated until the pressure data of all pressure sensors 60 are consistent. In this embodiment, through the cooperation of the pressure sensor 60 and the lifting device 50, the support height of the vacuum suction cups 30 can be quickly adjusted, thereby ensuring that each vacuum suction cup 30 maintains a balanced contact pressure with the wafer, facilitating the adhesion and adsorption of the vacuum suction cups 30 and the wafer.

[0046] Furthermore, in this embodiment, the support mechanism includes a first support rod 24 and a second support rod 25; the pressure sensor 60 is connected between the first support rod 24 and the second support rod 25, and bears the pressure of the first support rod 21 and the compressive force of the second support rod 25.

[0047] Please see Figure 6 and Figure 7 The vacuum suction cup 30 has multiple suction holes 32 on its surface, which are evenly distributed on the surface of the vacuum suction cup.

[0048] Please see Figure 8 N support mechanisms are arranged at equal intervals along the circumference of the fixing base 10 to form a support group, where N is a positive integer greater than or equal to 1. Further, there are multiple support groups, which are coaxially arranged on the fixing base 10. In this embodiment, there are three support groups: a first support group, a second support group, and a third support group, totaling 13 independent vacuum chucks 30. In the first support group, N is 8, and the first support group is positioned near the outer edge of the wafer; in the second support group, N is 4, and the second support group is positioned in the annular region at the center of the wafer; in the third support group, N is 1, and the third support group is positioned at the center of the wafer. The first, second, and third support groups are coaxially arranged on the fixing base 10. In this embodiment, by setting multiple support groups on the fixing base 10 and corresponding to different annular regions on the wafer back, the stability and reliability of wafer adsorption are improved.

[0049] How the wafer adsorption device works:

[0050] Step 1: The robotic arm transports the wafer above the vacuum chuck 30;

[0051] Step Two: Thirteen independent vacuum chucks 30 begin to rise under the action of the lifting device 50. Once the vacuum chucks 30 contact the wafer, each pressure sensor 60 begins to transmit pressure data to the control system. At this point, the balancing process begins.

[0052] Step 3: The control system calculates the average value of all pressure data and controls the vacuum chuck 30 to stop rising if the pressure data is higher than the average value, and raise the vacuum chuck 30 by 0.1 mm if the pressure data is lower than the average value; this action is repeated until the readings of all pressure sensors 60 are consistent. Under the contact force with the wafer, the vacuum chuck 30 will rotate slightly relative to the support rod 21 to adhere to the wafer; after the pressure data obtained by all pressure sensors 60 are consistent, the vacuum chuck 30 begins to adsorb the wafer, and the wafer is fixed on the wafer adsorption device before proceeding with the process.

[0053] In summary, the wafer adsorption device of this invention employs a structure combining multiple vacuum suction cups for vacuum adsorption of the wafer. Its advantage lies in that even when adsorption becomes unstable at a certain point on the wafer back due to dirt, the other vacuum suction cups in the assembly can still maintain stable adsorption of the wafer, thus overcoming the problem in existing technologies where wafers cannot be fixed by vacuum suction cups due to dirt on the wafer back. The vacuum suction cups are connected to the support mechanism via a rotating connection mechanism, enabling adaptive adjustment of the vacuum suction cups to better fit the wafer, thereby achieving a better vacuum adsorption effect. By setting pressure sensors on the support mechanisms of different vacuum suction cups to obtain the support pressure of each individual vacuum suction cup, the support height of the vacuum suction cups can be quickly adjusted according to the support pressure, thereby ensuring that each vacuum suction cup maintains a balanced contact pressure with the wafer, facilitating the adhesion and adsorption between the vacuum suction cups and the wafer. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0054] The above description is merely a specific implementation of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application. Therefore, the protection scope of the embodiments of this application should be determined by the protection scope of the claims.

Claims

1. A wafer adsorption device, characterized in that, The device includes a mounting base, on which multiple vacuum suction cup assemblies are arranged, the vacuum suction cup assemblies being used to adsorb and fix the wafer; The vacuum suction cup assembly includes: A support mechanism is connected to the fixed base; A vacuum chuck is connected to the end of the support mechanism away from the fixed base via a rotating connection mechanism, and the angle between the axis of the vacuum chuck and the axis of the support mechanism is adjustable. The vacuum chuck is used to adsorb the back side of the wafer by negative pressure. The support mechanism includes a support rod, the support rod having a first gas flow channel inside; the first gas flow channel is connected to the air extraction device; the rotating connection mechanism includes a second gas flow channel, the second gas flow channel being connected to the first gas flow channel and the second gas flow channel being connected to the vacuum suction cup; The rotating connection mechanism includes a first connector and a second connector. The first connector is connected to the support rod, and the second connector is connected to the vacuum suction cup. The first connector and the second connector are rotatably connected by a spherical pair.

2. The wafer adsorption device according to claim 1, characterized in that: The first connector has a first channel, and the second connector has a second channel, the first channel and the second channel being connected to form the second gas flow channel.

3. The wafer adsorption device according to claim 1, characterized in that: It also includes a lifting device; The bottom end of the support mechanism is connected to the fixed base through the lifting device, and reciprocates in a direction perpendicular to the top surface of the fixed base under the drive of the lifting device.

4. The wafer adsorption device according to claim 3, characterized in that: The support mechanism is equipped with a pressure sensor, which is used to detect the pressure on the support mechanism and transmit the pressure data to the control system of the lifting device.

5. The wafer adsorption device according to claim 4, characterized in that: The support mechanism includes a first support rod and a second support rod. The pressure sensor is connected between the first support rod and the second support rod, and bears the pressure of the first support rod and the compressive force of the second support rod.

6. The wafer adsorption device according to claim 1, characterized in that: The vacuum suction cup has multiple adsorption holes on its surface, which are evenly distributed on the surface of the vacuum suction cup.

7. The wafer adsorption device according to claim 1, characterized in that: N support mechanisms are arranged at equal intervals along the circumference of the fixed base to form a support group, where N is a positive integer greater than or equal to 1.

8. The wafer adsorption device according to claim 7, characterized in that: The number of support groups is multiple, and the multiple support groups are coaxially arranged on the fixed base.

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