Wafer marking device

Abstract

The present application relates to a kind of wafer marking device, including rack, support mechanism, handling mechanism and laser.The support mechanism includes rigid base plate, moving assembly and adsorption platform, rigid base plate is fixed to rack, adsorption platform is installed on rigid base plate by moving assembly, its bearing surface can generate negative pressure.Handling mechanism can first transfer the wafer to be marked to adsorption platform, and make the front of wafer be carried on the bearing surface of adsorption platform.Adsorption platform generates negative pressure, and wafer can be adsorbed and fixed on the bearing surface of adsorption platform.Wafer back fixed on adsorption platform faces upward.Then, moving assembly drives adsorption platform and wafer on it move along first direction and second direction, and laser can complete marking on each area of wafer back.Moreover, since wafer is fixed by being adsorbed on adsorption platform by negative pressure, there is no obstruction in its edge.Therefore, the whole area of wafer back can be marked by laser, so the utilization rate of wafer is higher.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment technology, and in particular to a wafer marking device. Background Technology

[0002] In the fabrication of integrated circuits, marking is required on the back of the wafer, typically using a laser marking machine. The back of the wafer to be marked is supported on an optical glass plate, through which a laser beam passes to perform the marking. To prevent the wafer from shifting during marking, its edges need to be held in place. Furthermore, to better secure the wafer, larger areas at the edges need to be pressed down. However, these pressed areas cannot be marked and therefore cannot be used to fabricate chips, resulting in low material utilization. Summary of the Invention

[0003] Therefore, it is necessary to provide a wafer marking device that can improve material utilization to address the above problems.

[0004] A wafer marking apparatus, comprising:

[0005] frame;

[0006] The support mechanism includes a rigid base plate, a moving component, and an adsorption platform. The rigid base plate is fixed to the frame. The adsorption platform is mounted on the rigid base plate via the moving component and can move along a first direction and a second direction that are perpendicular to each other under the drive of the moving component. The bearing surface of the adsorption platform can generate negative pressure.

[0007] A transport mechanism is used to transfer the wafer to be marked to the adsorption platform, and to place the front side of the wafer on the bearing surface of the adsorption platform; and

[0008] A laser is located above the bearing surface of the adsorption platform, and the laser is capable of marking the back side of the wafer supported on the adsorption platform.

[0009] In one embodiment, the rigid base plate is connected to the frame by shock-absorbing rubber.

[0010] In one embodiment, the adsorption platform includes a base and a ceramic suction cup. The base is fixed to the moving end of the moving component. The ceramic suction cup and the base cooperate through a foolproof mechanism, and the base can generate negative pressure to adsorb and fix the ceramic suction cup.

[0011] In one embodiment, the foolproof mechanism includes a fixing ring and a protrusion disposed on the base. The fixing ring is concentrically disposed with the base, and the protrusion is eccentrically disposed relative to the base. The ceramic suction cup has an annular groove and a positioning hole on the side facing the base, which can respectively cooperate with the fixing ring and the protrusion.

[0012] In one embodiment, the moving component includes a motion platform and a skateboard, the motion platform being slidably mounted on the rigid base plate along a first direction, the skateboard being slidably mounted on the motion platform along a second direction, and the adsorption platform being mounted on the skateboard.

[0013] In one embodiment, the system further includes an exhaust duct with its exhaust port facing the bearing surface of the adsorption platform.

[0014] In one embodiment, the handling mechanism includes a robotic arm and vacuum suction fingers, the vacuum suction fingers being located at the moving end of the robotic arm, and the vacuum suction fingers being able to suction the wafer and flip it.

[0015] In one embodiment, the rack is provided with a plurality of wafer cassette loaders, each of which is capable of receiving a wafer cassette containing the wafer, and the transport mechanism is capable of retrieving the wafer from a wafer cassette on any of the wafer cassette loaders.

[0016] In one embodiment, the device further includes an edge-finding and alignment mechanism, wherein the transport mechanism transports the wafer to the edge-finding and alignment mechanism and positions the wafer thereon, and the transport mechanism is also used to transport the wafer from the edge-finding and alignment mechanism to the adsorption platform.

[0017] In one embodiment, a visual positioning camera is also included below the support mechanism, the support mechanism having an avoidance structure, and the visual positioning camera is able to perform visual positioning of the wafer carried on the adsorption platform through the avoidance structure.

[0018] In the aforementioned wafer marking apparatus, the transport mechanism first transfers the wafer to be marked to the adsorption platform, ensuring the front side of the wafer rests on the platform's support surface. The adsorption platform generates negative pressure, thus adsorbing and fixing the wafer to its support surface. The back side of the wafer is fixed to the adsorption platform with its back side facing upwards. Next, the moving component moves the adsorption platform and the wafer along the first and second directions, allowing the laser to mark various areas on the back side of the wafer. Furthermore, because the wafer is fixed to the adsorption platform by negative pressure, its edges are not obstructed. Therefore, the entire back side of the wafer can be marked by the laser, resulting in high wafer utilization. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0020] Figure 1 This is a top view of the wafer marking apparatus in a preferred embodiment of the present invention;

[0021] Figure 2 for Figure 1 A partial front view of the support mechanism and laser in the wafer marking device shown;

[0022] Figure 3 for Figure 1 A top view of the adsorption platform in the wafer marking apparatus shown;

[0023] Figure 4 for Figure 3 The image shows a top view of the adsorption platform after the ceramic suction cup has been removed.

[0024] Figure 5 for Figure 1 A top view of the transport mechanism in the wafer marking device shown;

[0025] Figure 6 for Figure 1 The front view of the edge-finding and alignment mechanism in the wafer marking device shown. Detailed Implementation

[0026] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0029] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0031] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0032] Please see Figure 1 The wafer marking device 10 in a preferred embodiment of the present invention includes a frame 100, a support mechanism 200, a transport mechanism 300, and a laser 400.

[0033] The rack 100 provides support, and the support mechanism 200, the transport mechanism 300, and the laser 400 can all be mounted on the rack 100. Specifically, in this embodiment, multiple wafer cassette loaders 110 are provided on the rack 100, each capable of receiving a wafer cassette (not shown). The wafer cassettes containing wafers can be transported to the wafer marking device 10 via an overhead crane and received by the wafer cassette loaders 110. Moreover, the multiple wafer cassette loaders 110 can respectively receive wafer cassettes containing wafers of different models, thereby facilitating the wafer marking device 10 to perform marking processing on wafers of different models.

[0034] Specifically, this embodiment includes two wafer cassette loaders 110, each capable of receiving a 12-inch wafer cassette and an 8-inch wafer cassette, respectively. Furthermore, a glass sheet is attached to the front of the wafer inside the wafer cassette, providing protection for the front of the wafer.

[0035] Please refer to the following: Figure 2 The support mechanism 200 includes a rigid base plate 210, a moving component 220, and an adsorption platform 230.

[0036] A rigid base plate 210 is fixed to the frame 100. The rigid base plate 210 is formed from a highly rigid material, providing stable support for the entire support mechanism 200; a marble base plate can be used. Specifically, in this embodiment, the rigid base plate 210 is connected to the frame 100 via shock-absorbing rubber (not shown). The shock-absorbing rubber can attenuate vibrations from the ground and the frame 100, thereby further improving the stability of the support mechanism 200.

[0037] The adsorption platform 230 is mounted on the rigid base plate 210 via a movable component 220. Furthermore, the movable component 220 is capable of driving the adsorption platform 230 to move along two mutually perpendicular directions. Specifically, the first direction refers to... Figure 2 The direction shown is perpendicular to the plane of the drawing; the second direction refers to... Figure 2The left and right directions are shown.

[0038] In this embodiment, the moving component 220 includes a motion platform 221 and a sliding plate 222. The motion platform 221 is slidably mounted on the rigid base plate 210 along a first direction, and the sliding plate 222 is slidably mounted on the motion platform 221 along a second direction. The adsorption platform 230 is mounted on the sliding plate 222. The motion platform 221 can be formed from a metal sheet and can be mounted on the rigid base plate 210 via a guide rail-slider. The sliding plate 222 can also be mounted on the motion platform 221 via a guide rail-slider. The motion platform 221 and the sliding plate 222 have a large bearing area, which is more conducive to maintaining the stability of the adsorption platform 230.

[0039] Furthermore, the bearing surface of the adsorption platform 230 can generate negative pressure. The transport mechanism 300 is used to transfer the wafer to be marked to the adsorption platform 230, and to bear the front side of the wafer on the bearing surface of the adsorption platform 230. Specifically, the transport mechanism 300 can pick up wafers from wafer cassettes on the wafer cassette loader 110 and transfer them to the adsorption platform 230. Moreover, the transport mechanism 300 can pick up wafers from wafer cassettes on any wafer cassette loader 110.

[0040] To facilitate the switching of the handling mechanism 300 between different wafer cassettes for material handling, in this embodiment, a ground rail shaft 120 is provided on the frame 100, and the handling mechanism 300 is mounted on the frame 100 via the ground rail shaft 120. By sliding along the ground rail shaft 120, the handling mechanism 300 can move to the corresponding position of any wafer cassette loader 110, thereby facilitating material handling from the wafer cassettes on the wafer cassette loader 110.

[0041] Please refer to the following: Figure 5 In this embodiment, the handling mechanism 300 includes a robotic arm 310 and a vacuum adsorption finger 320. The vacuum adsorption finger 320 is located at the moving end of the robotic arm 310 and can adsorb wafers and flip them.

[0042] The vacuum adsorption fingers 320 are roughly U-shaped and typically made of ceramic to ensure that they do not contaminate the wafer during contact. Furthermore, wafers are always received face up. To ensure the wafer's face rests on the support surface of the adsorption platform 230, the vacuum adsorption fingers 320 can be rotated 180 degrees, so that the wafer adsorbed by the vacuum adsorption fingers 320 is face down.

[0043] After the wafer is transferred to the adsorption platform 230, the adsorption platform 230 generates a negative pressure, which adsorbs and fixes the wafer to the bearing surface of the adsorption platform 230. Moreover, since the front side of the wafer faces the bearing surface of the adsorption platform 230, the back side of the wafer on the adsorption platform 230 faces upward. At this time, the moving component 220 moves the adsorption platform 230 and the wafer on it along the first direction and the second direction, so that the wafer is moved to the precise marking position. The laser 400 located above the bearing surface of the adsorption platform 230 emits a laser beam, which can complete the marking of various areas on the back side of the wafer.

[0044] Compared with existing marking devices, the above-mentioned wafer marking device 10 has at least the following advantages:

[0045] 1. Since the wafer is fixed on the adsorption platform 230 by negative pressure adsorption, there is no obstruction at its edges. Therefore, the entire area on the back of the wafer can be marked by the laser 400, resulting in high wafer utilization.

[0046] 2. Since the laser 400 is located above the bearing surface of the adsorption platform 230, the dust generated during marking will not fall onto the galvanometer 410 of the laser 400, thus keeping the surface of the galvanometer 410 clean.

[0047] 3. The wafer can be supported entirely on the bearing surface of the adsorption platform 230, so the wafer will not deform due to gravity. Therefore, the marking accuracy is also improved.

[0048] Please refer to it again. Figure 2 In this embodiment, the wafer marking apparatus 10 further includes an exhaust duct 500, the exhaust port of which (not shown) faces the bearing surface of the adsorption platform 230. The exhaust duct 500 can be connected to an external dust collector (not shown), which can create negative pressure at the exhaust port of the exhaust duct 500. Therefore, dust generated during the marking process can be drawn into the dust collector through the exhaust duct 500, and after being filtered by the dust collector, clean air is discharged, preventing dust from contaminating the equipment and the workshop environment.

[0049] In this embodiment, the wafer marking device 10 also includes a detection camera 700 disposed above the bearing surface of the adsorption platform 230. The detection camera 700 can take pictures of the wafers on the adsorption platform 230 and detect the marking accuracy.

[0050] In this embodiment, the wafer marking device 10 also includes a visual positioning camera (not shown) located below the support mechanism 200. The support mechanism 200 has an avoidance structure (not shown), and the visual positioning camera can perform visual positioning of the wafer carried on the adsorption platform 230 through the avoidance structure.

[0051] Specifically, the front side of the wafer is marked with points, and the visual positioning camera can determine the position of the wafer by locating these points, thereby guiding the laser 400 to perform marking. The obstruction structure should penetrate the rigid base plate 210, the moving component 220, and the adsorption platform 230 to provide a viewing angle for the visual positioning camera and prevent obstruction of the camera.

[0052] Furthermore, since the lens of the visual positioning camera faces upwards, dust generated during the marking process easily falls onto the lens, causing lens contamination. To avoid this problem, an air blowing pipe (not shown) is usually installed below the support mechanism 200, which blows air towards the lens of the visual positioning camera. In this way, regular air blowing can prevent dust from accumulating on the lens, thereby achieving the purpose of cleaning the lens.

[0053] Please refer to the following: Figure 3 and Figure 4 In this embodiment, the adsorption platform 230 includes a base 231 and a ceramic suction cup 232. The base 231 is fixed to the moving end of the moving component 220. The ceramic suction cup 232 and the base 231 cooperate through a foolproof mechanism, and the base 231 can generate negative pressure to adsorb and fix the ceramic suction cup 232.

[0054] Specifically, the base 231 can be a metal plate structure, which can be fixed to the moving end of the moving component 220, i.e., the surface of the slide plate 222, by means of threaded fastening or other methods. The ceramic suction cup 232 is disc-shaped, and its diameter is slightly larger than the diameter of the wafer to be processed, so the wafer can be supported entirely on the surface of the ceramic suction cup 232. When processing different types of wafers, only the ceramic suction cup 232 needs to be replaced to achieve hardware switching, while the base 231 does not need to be replaced.

[0055] Since the ceramic suction cup 232 is fixed to the base 231 by negative pressure adsorption, the ceramic suction cup 232 can be removed by removing the vacuum. Furthermore, the foolproof mechanism allows the ceramic suction cup 232 and base 231 to be quickly assembled and ensures repeatability of positioning accuracy after switching to the ceramic suction cup 232. Therefore, the simple and convenient assembly and disassembly method for the ceramic suction cup 232 shortens the cutting time and thus helps improve processing efficiency.

[0056] Furthermore, in this embodiment, the foolproof mechanism includes a fixing ring 2311 and a protrusion 2312 disposed on the base 231. The fixing ring 2311 is concentrically disposed with the base 231, and the protrusion 2312 is eccentrically disposed with respect to the base 231. The ceramic suction cup 232 has an annular groove (not shown) and a positioning hole (not shown) on the side facing the base 231, which can respectively cooperate with the fixing ring 2311 and the protrusion 2312.

[0057] The retaining ring 2311 can be a plastic ring that is fixed and protrudes from the surface of the base 231, and can achieve center positioning by cooperating with the annular groove of the ceramic suction cup 232. The protruding post 2312 can be a plastic cylinder, and can determine the circumferential position of the ceramic suction cup 232 by cooperating with the positioning hole of the ceramic suction cup 232. Through dual positioning, the position of the ceramic suction cup 232 can be accurately positioned when switching the ceramic suction cup 232. Moreover, the retaining ring 2311 and the protruding post 2312 can also play a radial limiting role, thereby preventing the ceramic suction cup 232 from slipping off the surface of the base 231 due to the lack of external force when the base 231 accidentally loses vacuum.

[0058] Please refer to it again. Figure 1 In this embodiment, the wafer marking device 10 further includes an edge-finding and alignment mechanism 600. The transport mechanism 300 transports the wafer to the edge-finding and alignment mechanism 600 and positions the wafer. The transport mechanism 300 is also used to transport the wafer from the edge-finding and alignment mechanism 600 to the adsorption platform 230.

[0059] Please refer to the following: Figure 6 The edge-finding and alignment mechanism 600 generally includes an edge finder 610, a barcode scanner 620, and an adjustment module 630. The transport mechanism 300 first places the wafer on the edge finder 610, which then automatically locates and positions the wafer. After positioning, the barcode scanner 620 captures and reads the QR code information on the wafer to obtain processing information. The adjustment module 630 adjusts the relative position of the barcode scanner 620 and the edge finder 610, thus enabling scanning of wafers of different models. The adjustment module 630 can be implemented using a servo motor and a ball screw slide.

[0060] The wafer marking apparatus 10 described above includes a transport mechanism 300 that first transfers the wafer to be marked to the adsorption platform 230, ensuring the front side of the wafer rests on the support surface of the adsorption platform 230. The adsorption platform 230 generates negative pressure, thus adsorbing and fixing the wafer to its support surface. The back side of the wafer fixed on the adsorption platform 230 faces upwards. Next, the moving component 220 moves the adsorption platform 230 and the wafer on it along the first and second directions, allowing the laser 400 to mark various areas on the back side of the wafer. Furthermore, because the wafer is fixed by negative pressure adsorption on the adsorption platform 230, its edges are not obstructed. Therefore, the entire back side of the wafer can be marked by the laser 400, resulting in high wafer utilization.

[0061] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A wafer marking device, characterized in that, include: frame; The support mechanism includes a rigid base plate, a moving component, and an adsorption platform. The rigid base plate is fixed to the frame. The adsorption platform is mounted on the rigid base plate via the moving component and can move along mutually perpendicular first and second directions under the drive of the moving component. The bearing surface of the adsorption platform can generate negative pressure. A transport mechanism is used to transfer the wafer to be marked to the adsorption platform, and to place the front side of the wafer on the bearing surface of the adsorption platform; and A laser is located above the bearing surface of the adsorption platform, and the laser is capable of marking the back side of the wafer supported on the adsorption platform; The adsorption platform includes a base and a ceramic suction cup. The base is fixed to the moving end of the moving component, and the ceramic suction cup cooperates with the base through a foolproof mechanism. The foolproof mechanism includes a fixing ring and a protrusion disposed on the base. The fixing ring is concentrically disposed with the base, and the protrusion is eccentrically disposed with respect to the base. The ceramic suction cup has an annular groove and a positioning hole on the side facing the base, which can respectively cooperate with the fixing ring and the protrusion. It also includes a visual positioning camera located below the support mechanism. The support mechanism has an avoidance structure. The visual positioning camera can perform visual positioning of the wafer carried on the adsorption platform through the avoidance structure. The avoidance structure penetrates the rigid base plate, the moving component and the adsorption platform. The edge-finding and alignment mechanism is used to transport the wafer to the edge-finding and alignment mechanism and position the wafer. The transport mechanism is also used to transport the wafer from the edge-finding and alignment mechanism to the adsorption platform.

2. The wafer marking apparatus according to claim 1, characterized in that, The rigid base plate is connected to the frame by shock-absorbing rubber.

3. The wafer marking apparatus according to claim 1, characterized in that, The base can generate negative pressure to attract and fix the ceramic suction cup.

4. The wafer marking apparatus according to claim 1, characterized in that, The moving component includes a motion platform and a skateboard. The motion platform is slidably mounted on the rigid base plate along the first direction, and the skateboard is slidably mounted on the motion platform along the second direction. The adsorption platform is mounted on the skateboard.

5. The wafer marking apparatus according to claim 1, characterized in that, It also includes an exhaust duct, the exhaust port of which is positioned facing the bearing surface of the adsorption platform.

6. The wafer marking apparatus according to claim 1, characterized in that, The handling mechanism includes a robotic arm and vacuum suction fingers. The vacuum suction fingers are located at the moving end of the robotic arm and can suction the wafer and flip it.

7. The wafer marking apparatus according to claim 1, characterized in that, The rack is equipped with multiple wafer cassette loaders, each of which can receive a wafer cassette containing the wafer. The transport mechanism can retrieve the wafer from a wafer cassette on any of the wafer cassette loaders.

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