Adsorption mechanism and wafer edge searching device

Abstract

The utility model relates to an adsorption mechanism and a wafer edge searching device. The adsorption mechanism can cooperate with a fixed sucker of the wafer edge searching device to adsorb a wafer. Wherein the adsorption mechanism comprises a supporting piece and a plurality of Bernoulli suction cups, the supporting piece is arranged in a surrounding mode to form a receding part capable of receding the fixed suction cups, and the Bernoulli suction cups are installed on the supporting piece and distributed in the circumferential direction of the receding part at intervals. When the warping degree of the wafer is too large and the fixed suction cup cannot smoothly adsorb and fix the wafer, the Bernoulli suction cup can be started to generate a downward suction force to the wafer, so that the wafer is leveled in the circumferential direction of the fixed suction cup. After the wafer is leveled by the Bernoulli suction cup, the gap between the wafer and the fixed suction cup is obviously reduced, so that vacuum leakage is not easy to generate, and the wafer can be smoothly adsorbed and fixed by opening the fixed suction cup. Therefore, the adsorption mechanism can ensure that the fixed suction cup of the wafer edge searching device smoothly adsorbs the warped wafer.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of semiconductor equipment, especially to an adsorption mechanism and wafer edge finding device. BACKGROUND

[0002] In the semiconductor processing process, the wafer is often adsorbed and fixed. For example, the wafer edge finding device is one of the key devices in the semiconductor production process, and its function is to find the edge and position of the wafer to facilitate the next process. The wafer to be positioned is generally first adsorbed by the vacuum chuck of the wafer edge finding device, and then the angle and position are adjusted. However, the wafer that has undergone multiple process procedures will inevitably accumulate a large amount of stress, causing local or overall warping deformation of the wafer. When the wafer warping reaches a certain degree, a large gap will be formed between the vacuum chuck and the wafer it carries, so that a vacuum cannot be established. Therefore, the vacuum chuck cannot successfully adsorb and fix the warped wafer, causing the wafer edge finding device to fail to open smoothly, thereby affecting the production efficiency. SUMMARY

[0003] Therefore, it is necessary to provide an adsorption mechanism and wafer edge finding device that can ensure that the fixed chuck successfully adsorbs the warped wafer.

[0004] An adsorption mechanism can cooperate with a fixed chuck to adsorb a wafer. The adsorption mechanism includes a support and a plurality of Bernoulli chucks. The support surrounds an empty space that can form a clearance for the fixed chuck. The plurality of Bernoulli chucks are installed on the support and are spaced apart along the circumference of the empty space.

[0005] In one embodiment, the adsorption mechanism further includes a buffer installed on the support, which protrudes from the surface of the Bernoulli chuck along the axial direction of the empty space.

[0006] In one embodiment, the buffer is distributed on both sides of each Bernoulli chuck.

[0007] In one embodiment, the support is provided in the form of a ring structure with a gap.

[0008] In one embodiment, the adsorption mechanism further includes a lifting assembly, which is in transmission connection with the support and can drive the support to move reciprocally along the axial direction of the empty space.

[0009] In one embodiment, the lifting assembly includes a base, a plurality of columns, and at least one driving member. The plurality of columns are slidably installed on the base along the axial direction of the empty space and connected to the support. The driving member is connected to at least one of the columns and can drive the column to slide relative to the base.

[0010] In one of the embodiments, the base is arranged in a U-shaped structure with an opening.

[0011] In one of the embodiments, the support is internally formed with a first air passage in communication with each of the Bernoulli chuck, and the at least one column is internally formed with a second air passage in communication with the first air passage.

[0012] In one of the embodiments, the lifting assembly further comprises a limiting assembly capable of limiting the stroke of the column sliding relative to the base.

[0013] A wafer edge finding device comprises an edge finder and the above-mentioned adsorption mechanism of any one of the preferred embodiments, the edge finder comprises a fixed chuck, and the adsorption mechanism is installed on the edge finder and makes the fixed chuck located within the range of the air clearance.

[0014] The above-mentioned adsorption mechanism and wafer edge finding device can place the wafer to be found on the fixed chuck, and then complete the edge finding operation under the driving of the edge finder after the wafer is adsorbed and fixed by the fixed chuck. When the warpage of the wafer is too large and causes the fixed chuck to fail to adsorb and fix the wafer smoothly, the Bernoulli chuck can be started to generate a downward suction force on the wafer, so as to flatten the wafer along the circumference of the fixed chuck. After the wafer is flattened by the Bernoulli chuck, the gap between the wafer and the fixed chuck will be significantly reduced, so that the vacuum leakage is not easy to occur, and then the fixed chuck can adsorb and fix the wafer smoothly. It can be seen that the above-mentioned adsorption mechanism can ensure that the fixed chuck of the wafer edge finding device adsorbs and fixes the warped wafer smoothly. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0016] Figure 1 It is a structure schematic view of the wafer edge finding device in the preferred embodiment of the present application.

[0017] Figure 2 It is a structure schematic view of the wafer edge finding device in the preferred embodiment of the present application. Figure 1 It is a structure schematic view of the adsorption mechanism in the wafer edge finding device. DETAILED DESCRIPTION

[0018] In order to make the above object, characteristics and advantages of the present application more apparent, concrete embodiments of the present application will be described in detail with reference to the drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different manners without departing from the spirit of the present application. Those skilled in the art will appreciate the scope of the present application and can make similar modifications without departing from the spirit of the present application. Therefore, the present application is not limited by the embodiments disclosed below.

[0019] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship 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 devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0020] 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 the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0021] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0022] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0023] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on another element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only implementation.

[0024] Please refer to Figure 1 The utility model provides a kind of wafer edge finding device 10 and adsorption mechanism 100. Among them, the wafer edge finding device 10 described above includes adsorption mechanism 100 and edge finder 200.

[0025] The edge finder 200 includes a fixed chuck 210, which is usually a vacuum chuck and can also be a Bernoulli chuck, used to adsorb and fix the wafer. Usually, the wafer is first taken out of the magazine by a robot and placed on the fixed chuck 210. Since the relative position of the wafer and the center of the fixed chuck 210 is random, before transferring the wafer to the next process, the actual position of the wafer needs to be obtained by scanning the edge and notch of the wafer with a laser sensor, and then the edge finder 200 adjusts the angle of the wafer and translates the wafer to adjust it to the theoretical center position. Specifically, the edge finder 200 can use a conventional edge finder, so its specific structure is not described here.

[0026] In some embodiments, the adsorption mechanism 100 can cooperate with the fixed chuck 210 to adsorb the wafer, so as to ensure that the fixed chuck 210 can successfully adsorb and fix the warped wafer. The adsorption mechanism 100 functions to flatten the warped wafer, so as to reduce the gap between the wafer and the fixed chuck 210, so that the wafer and the fixed chuck 210 are closely attached. After the fixed chuck 210 successfully adsorbs and fixes the wafer, the adsorption mechanism 100 is released from the adsorption state, so as to facilitate the edge finder to adjust the wafer to the theoretical center position by rotating or displacing. In other embodiments, the adsorption mechanism 100 can also cooperate with other devices to adsorb and fix the wafer or other thin plate-shaped workpieces prone to warping. The adsorption mechanism 100 can also independently adsorb and fix the wafer or other thin plate-shaped workpieces prone to warping.

[0027] Please refer to Figure 2 The adsorption mechanism 100 in the preferred embodiment of the utility model includes a support 110 and a plurality of Bernoulli chucks 120.

[0028] The support 110 is generally formed by a metal plate and has high structural strength, and can be used to support the Bernoulli chucks 120 and other elements. The support 110 is arranged to form a clearance 101 capable of forming a clearance for the fixed chuck 210. The adsorption mechanism 100 is installed on the edge finder 200, and the fixed chuck 210 is located within the range of the clearance 101. The plurality of Bernoulli chucks 120 are installed on the support 110 and are spaced apart along the circumferential direction of the clearance 101. That is, the plurality of Bernoulli chucks 120 are also spaced apart along the circumferential direction of the fixed chuck 210.

[0029] When the degree of warping of the wafer is too large and causes the fixed chuck 210 to fail to successfully establish a vacuum with the wafer, the Bernoulli chucks 120 can be started. Since the Bernoulli chucks 120 can achieve non-contact adsorption, the Bernoulli chucks 120 can generate a downward suction force on the wafer on the fixed chuck 210. Moreover, the plurality of Bernoulli chucks 120 are spaced apart along the circumferential direction of the fixed chuck 210, so that the plurality of Bernoulli chucks 120 can exert a force on the wafer along the circumferential direction of the fixed chuck 210 to flatten the wafer. After the wafer is flattened by the Bernoulli chucks 120, the gap between the wafer and the fixed chuck 210 is significantly reduced, so that vacuum leakage is less likely to occur. After the fixed chuck 210 is started again, the wafer can be successfully adsorbed and fixed. As can be seen, with the assistance of the adsorption mechanism 100, the fixed chuck 210 can successfully adsorb and fix the warped wafer, thereby reducing the probability that the wafer edge finding device 10 cannot be started due to the wafer failing to be adsorbed, ensuring that the edge finding operation proceeds in an orderly manner, and helping to improve production efficiency.

[0030] Moreover, the adsorption mechanism 100 can be used as an external accessory in cooperation with a conventional edge finder 200, without changing the structure of the existing edge finder 200, and has strong applicability and helps to save costs. For the scenario where the wafer is prone to large degree warping, the adsorption mechanism 100 can be quickly installed externally with the edge finder 200. For the scenario where the wafer is not prone to warping, the external adsorption mechanism 100 can be quickly disassembled and only the edge finder 200 is retained to save installation space.

[0031] In the embodiment, the support 110 is provided in a ring structure with a gap. Specifically, the support 110 can be an arc-shaped metal plate. Since the support 110 has a gap, the inherent structure on the edge finder 200 can be avoided through the gap, thereby facilitating the installation of the adsorption mechanism 100 without changing the structure of the existing edge finder 200.

[0032] Moreover, when the support 110 is semicircular, the avoidance space 101 formed by the support 110 is approximately circular, and the suction cup 210 can be fixed to achieve concentric arrangement. In this way, the distance between the plurality of Bernoulli suction cups 120 on the support 110 and the center of the fixed suction cup 210 in the avoidance space 101 is approximately the same, so that the wafer can be balanced when being flattened.

[0033] In the embodiment, the adsorption mechanism 100 further includes a buffer 130 mounted on the support 110, and the buffer 130 protrudes from the surface of the Bernoulli suction cup 120 along the axial direction of the avoidance space 101. Specifically, the buffer 110 is formed of flexible materials such as rubber and silica gel, and can be a buffer suction cup.

[0034] In the process of starting the Bernoulli suction cup 120 to flatten the warped wafer, the wafer will be returned towards the Bernoulli suction cup 120. By adjusting the flow and pressure of the positive pressure flowing through the Bernoulli suction cup 120, the wafer can just contact the buffer 110 in the process of recovering the warping. The buffer 110 can buffer the wafer, thereby avoiding damage caused by the wafer colliding with the surface of the Bernoulli suction cup 120.

[0035] Further, in the embodiment, the buffer 130 is distributed on both sides of each Bernoulli suction cup 120. The buffers 130 on both sides have better support for the wafer, which can further avoid the wafer from directly contacting the surface of the Bernoulli suction cup 120, and improve the buffering effect on the wafer.

[0036] Specifically, each Bernoulli suction cup 120 corresponds to a suction cup base 111, and three hole positions for mounting the Bernoulli suction cup 120 and the buffer 130 are formed on the suction cup base 111. Among them, the Bernoulli suction cup 120 is mounted in the middle hole position, and the two buffers 130 are respectively mounted in the other two hole positions.

[0037] Further, in the embodiment, the adsorption mechanism 100 further comprises a lifting assembly 140, which is in driving connection with the support 110 and capable of driving the support 110 to reciprocate along the axis of the clearance 101.

[0038] The axis of the clearance 101 generally refers to the vertical direction in actual use. When it is needed to flatten the warped wafer, the lifting assembly 140 first drives the support 110 to ascend, so as to drive the Bernoulli chuck 120 on the support 110 to move towards the wafer on the fixed chuck 210, thereby ensuring that the Bernoulli chuck 120 can smoothly exert downward suction force on the wafer. After the wafer is flattened, the fixed chuck 210 is started to adsorb the wafer. Then, the positive pressure of the fixed chuck 210 is disconnected and the support 110 is driven by the lifting assembly 140 to descend, so as to make the support 110 and the Bernoulli chuck 120 thereon away from the wafer. In this way, it can be avoided that the adsorption mechanism 100 interferes with the edge finding action after the edge finder 200 is started to find the edge.

[0039] Further, in the embodiment, the lifting assembly 140 comprises a base 141, a plurality of columns 142 and at least one driving member 143. The plurality of columns 142 are slidably mounted on the base 141 along the axis of the clearance 101 and connected with the support 110. The driving member 143 is connected with at least one column 142 and capable of driving the column 142 to slide relative to the base 141.

[0040] The base 141 can cooperate with the main body part of the edge finder 200, so as to externally mount the adsorption mechanism 100 on the edge finder 200. Specifically, in the embodiment, the base 141 is provided in a U-shaped structure with an opening. The U-shaped base 141 can form a clearance for the main body part of the edge finder 200, so that when mounted, the main body part of the edge finder 200 can be clamped into the U-shaped space formed by the base 141, so that the edge finder 200 and the adsorption mechanism 100 partially overlap, thereby helping to reduce the size of the small wafer edge finding device 10.

[0041] The plurality of columns 142 are not distributed on the same line, for example, the three columns 142 are distributed in a triangular shape, so as to provide stable support for the support 110. The driving member 143 can be a pneumatic cylinder, and the extension shaft thereof can be connected with the column 142 through a cylinder connecting plate 144. The driving member 143 drives the column 142 to slide relative to the base 141, so as to drive the support 110 to move along the axis of the clearance 101, thereby driving the plurality of Bernoulli chucks 120 to move close to or away from the wafer. For the case of providing three columns 142, two driving members 143 can be provided. The two driving members 143 are respectively connected with two columns 142, and capable of simultaneously driving the two columns 142 to ascend or descend, thereby avoiding the support 110 from tilting due to uneven force.

[0042] In order to control the lifting range of the support 110 and the Bernoulli chuck 120, and avoid the support 110 and the Bernoulli chuck 120 thereon from colliding with other structures on the edge finder 200, the lifting assembly 140 in the embodiment further comprises a limiting assembly (not labeled in the figure), which can limit the sliding stroke of the column 142 relative to the base 141, so as to achieve the purpose of controlling the lifting range of the support 110 and the Bernoulli chuck 120.

[0043] More specifically, the base 141 is provided with a plurality of slider mounting columns 1411 extending upward, and a guide rail slider assembly (not labeled in the figure) can be mounted on the slider mounting columns 1411. The plurality of columns 142 can be slidably mounted on the corresponding slider mounting columns 1411 through the guide rail slider assembly. At least part of the slider mounting columns 1411 is in a U-shaped structure with the opening facing downward, and the driving member 143 is accommodated in the U-shaped space of the slider mounting column 1411, so as to reduce the volume of the adsorption mechanism 100.

[0044] The cylinder connecting plate 144 is arranged in the U-shaped space of the slider mounting column 1411, and can abut against the slider mounting column 1411 during the process of driving the column 142 to drive the support 110 to rise by the driving member 143, so as to limit the upward stroke of the column 142, and avoid the support 110 from rising too high to collide with other structures on the edge finder 200. That is, the cylinder connecting plate 144 and the slider mounting column 1411 can also serve as part of the limiting assembly.

[0045] Further, in the embodiment, the base 141 is provided with a limiting block 1412, and at least one column 142 is provided with a limiting plate 1421, which can abut against the limiting block 1412 during the process of driving the column 142 to slide by the driving member 143.

[0046] The limiting block 1412 can be arranged on the slider mounting column 1411. During the process of driving the column 142 to slide and drive the support 110 to descend by the driving member 143, the limiting plate 1421 can abut against the limiting block 1412, so as to limit the downward stroke of the column 142, and avoid the support 110 from descending too low to collide with other structures on the edge finder 200. It can be seen that the limiting block 1412 and the limiting plate 1421 can also serve as part of the limiting assembly.

[0047] It should be noted that in other embodiments, the stroke of the column 142 can also be limited by the stroke of the driving member 143 itself.

[0048] In addition, in the embodiment, the inside of the support 110 is formed with a first air channel (not shown) in communication with each Bernoulli chuck 120, and the inside of at least one column 142 is formed with a second air channel (not shown) in communication with the first air channel.

[0049] When the Bernoulli chuck 120 is started, the positive pressure airflow can enter the corresponding Bernoulli chuck 120 through the second air channel and the first air channel in sequence. It can be seen that by integrating the air channels in the inside of the support 110 and the column 142, the outside of the adsorption mechanism 100 does not need to additionally set the pipeline for the airflow to pass through, so that the structure of the adsorption mechanism 100 can be simplified, and interference caused by the external pipeline to the working process of the wafer edge finding device 10 can be avoided. Specifically, the column 142 formed with the second air channel is generally also provided with an air nozzle connector 1422 in communication with the second air channel.

[0050] The adsorption mechanism 100 and the wafer edge finding device 10 described above can place the wafer to be edged on the fixed chuck 210, and complete the edging operation under the driving of the edger 200 after being adsorbed and fixed by the fixed chuck 210. When the warping degree of the wafer is too large and causes the fixed chuck 210 to fail to adsorb and fix it smoothly, the Bernoulli chuck 120 can be started to generate a downward suction force on the wafer, so as to flatten the wafer along the circumference of the fixed chuck 210. After the wafer is flattened by the Bernoulli chuck 120, the gap between the wafer and the fixed chuck 210 will be significantly reduced, so that vacuum leakage is not easy to occur, and the fixed chuck 210 can be started again to adsorb and fix the wafer smoothly. It can be seen that the adsorption mechanism 100 described above can ensure that the fixed chuck 210 of the wafer edge finding device 10 adsorbs the warped wafer smoothly.

[0051] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above-described embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the description.

[0052] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An adsorption mechanism capable of adsorbing a wafer in conjunction with a fixed suction cup, characterized in that, The adsorption mechanism includes a support member and a plurality of Bernoulli suction cups. The support member is configured to form a clearance that can avoid the fixed suction cups. The plurality of Bernoulli suction cups are installed on the support member and are distributed at intervals along the circumference of the clearance.

2. The adsorption mechanism according to claim 1, characterized in that, The adsorption mechanism further includes a buffer member installed on the support member, the buffer member protruding axially from the surface of the Bernoulli suction cup along the clearance portion.

3. The adsorption mechanism according to claim 2, characterized in that, Each of the Bernoulli suction cups has a buffer element distributed on both sides.

4. The adsorption mechanism according to claim 1, characterized in that, The support member is configured as a ring structure with a notch.

5. The adsorption mechanism according to any one of claims 1 to 4, characterized in that, The adsorption mechanism also includes a lifting component, which is connected to the support member and can drive the support member to reciprocate along the axial direction of the clearance portion.

6. The adsorption mechanism according to claim 5, characterized in that, The lifting assembly includes a base, multiple columns, and at least one drive member. The multiple columns are slidably mounted on the base along the axial direction of the clearance portion and connected to the support member. The drive member is connected to at least one of the columns and can drive the column to slide relative to the base.

7. The adsorption mechanism according to claim 6, characterized in that, The base is configured as a U-shaped structure with an opening.

8. The adsorption mechanism according to claim 6, characterized in that, The support member has a first air passage that communicates with each of the Bernoulli suction cups, and at least one of the columns has a second air passage that communicates with the first air passage.

9. The adsorption mechanism according to claim 6, characterized in that, The lifting assembly also includes a limiting component, which can limit the sliding stroke of the column relative to the base.

10. A wafer edge-finding device, characterized in that, The device includes an edge finder and an adsorption mechanism as described in any one of claims 1 to 9, wherein the edge finder includes a fixed suction cup, the adsorption mechanism is installed on the edge finder, and the fixed suction cup is located within the clearance portion.

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