Wafer ring removal device and ring removal method

Abstract

The embodiment of the present application provides a wafer ring removal device and a ring removal method, wherein the ring removal device performs a ring removal operation on the wafer; the wafer includes: a thinned wafer body and a thinning ring surrounding the thinned wafer body; the wafer ring removal device includes: a ring removal unit for separating the thinned wafer body and the thinning ring, and removing the thinning ring; a scanning unit for determining the position of a wafer base for placing the wafer, and a first relative position of the thinning ring relative to the center of the wafer base; a calculation unit for calculating the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base; a control unit for adjusting the relative position of the ring removal unit and the thinning ring based on the second relative position, and controlling the ring removal unit. The use of the wafer ring removal device and ring removal method of the present invention can reduce the risk of the ring removal unit scratching the wafer.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and in particular to a wafer ring removal device and a ring removal method. Background Art

[0002] To improve chip heat dissipation efficiency, reduce chip packaging volume, reduce internal chip stress, and improve electrical performance, wafer thinning is necessary. The wafer thinning process does not thin the entire wafer surface, but only the center portion. The edges of the wafer remain unthinned, forming a thinning ring that is removed by a ring removal unit.

[0003] However, during the ring removal process, there is a problem that the wafer is scratched by the ring removal unit. Therefore, how to provide a technical solution to reduce the risk of the ring removal unit scratching the wafer has become a technical problem that those skilled in the art urgently need to solve. Summary of the Invention

[0004] The technical problem solved by the present invention is to reduce the risk of the wafer being scratched by the ring removal unit by providing a wafer ring removal device and a ring removal method.

[0005] In order to solve the above problems, an embodiment of the present invention provides a wafer ring removal device, which performs a ring removal operation on the wafer; the wafer includes: a thinned wafer body and a thinning ring surrounding the thinned wafer body; the wafer ring removal device includes: a ring removal unit, used to separate the thinned wafer body and the thinning ring, and remove the thinning ring; a scanning unit, used to determine the position of the wafer base for placing the wafer, and the first relative position of the thinning ring relative to the center of the wafer base; a calculation unit, used to calculate the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base; a control unit, which adjusts the relative position of the ring removal unit and the thinning ring according to the second relative position, and controls the ring removal unit.

[0006] Optionally, the ring removal device includes: a bracket capable of moving relative to the wafer base;

[0007] The ring removal unit comprises:

[0008] a ring-taking gripper capable of grasping the thinned ring;

[0009] at least three first connecting rods, one end of each first connecting rod being movably connected to the bracket, and the other end of each first connecting rod being rotatably connected to a ring removal clamp;

[0010] Wherein, the first connecting rods surround the bracket and are evenly distributed.

[0011] Optionally, the scanning unit includes:

[0012] a second connecting rod, one end of which is movably connected to the bracket;

[0013] a light sensor connected to the other end of the second connecting rod and used to obtain the position of the thinning ring;

[0014] The light sensor is coupled to the computing unit.

[0015] Optionally, the ring removal device further includes:

[0016] coarse alignment unit;

[0017] The coarse alignment unit includes:

[0018] a third connecting rod, one end of which is connected to the bracket;

[0019] A coarse alignment clamp is connected to the other end of the third connecting rod and is used to place the wafer on the wafer base so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error.

[0020] Optionally, the cross-sectional shape of the ring removal clamp on a plane perpendicular to the wafer base is an "I" shape.

[0021] Optionally, the ring removal device further includes:

[0022] The contact end between the ring-removing clamp and the thinned ring includes one or more of a square cylinder, a circular cylinder, an elliptical cylinder, and a cone.

[0023] Optionally, the ring removal device further includes:

[0024] Circular cutting tape, used for bonding crystal circles;

[0025] a circular cutting tape frame for removing the circular cutting tape, the circular cutting tape frame being located on an edge region of the circular cutting tape;

[0026] The bonded wafer is located on the central area of ​​the dicing tape and is spaced apart from the dicing tape frame.

[0027] Optionally, the ring removal unit further includes: a pressure sensing module, which is arranged on the ring removal clamp in a one-to-one correspondence and is used to test the force exerted by the ring removal clamp on the wafer.

[0028] Optionally, the ring removal device further includes: a motor coupled to the coarse alignment jaw and the ring removal jaw, and the control unit controls the motor to drive the coarse alignment jaw and the ring removal jaw to move.

[0029] Accordingly, an embodiment of the present invention further provides a wafer ring removal method, which is applied to a wafer ring removal device; the wafer comprises: a thinned wafer body and a thinning ring surrounding the thinned wafer body;

[0030] The wafer ring removal device includes:

[0031] Ring taking unit, scanning unit, calculation unit, control unit;

[0032] The ring removal method comprises:

[0033] Adsorbing the wafer with the dicing tape on it onto the wafer base;

[0034] Using the scanning unit, determining a position of a wafer base for placing the wafer and a first relative position of the thinning ring relative to a center of the wafer base;

[0035] Using the calculation unit, calculate a second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base;

[0036] The control unit is used to adjust the relative position of the ring removing unit and the thinning ring according to the second relative position, and control the ring removing unit to separate the thinned wafer body and the thinning ring, and remove the thinning ring.

[0037] Optionally, the wafer ring removal device further includes: a coarse alignment unit;

[0038] The coarse alignment unit comprises: a coarse alignment clamping jaw;

[0039] Before placing the wafer with the dicing tape bonded thereto on the wafer base, the ring removal method further includes:

[0040] The control unit is used to adjust the positions of the wafer and the wafer base through the coarse alignment clamps of the coarse alignment unit so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error.

[0041] Compared with the prior art, the technical solution of this embodiment has the following advantages:

[0042] The wafer ring removal device described in the present invention is used to perform ring removal operations on wafers; the wafer includes: a thinned wafer body and a thinning ring surrounding the thinned wafer body; the wafer ring removal device includes: a ring removal unit, a scanning unit, a calculation unit, and a control unit; the calculation unit calculates the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the position and the first relative position of the wafer base obtained by the scanning unit, that is, calculates the offset between the center of the thinned wafer body and the center of the wafer base; the control unit adjusts the relative position of the ring removal unit and the thinning ring according to the offset, controls the ring removal unit to remove the ring, and reduces the risk of the ring removal unit scratching the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0044] Figure 1 It is a structural diagram of a ring removal device;

[0045] Figure 2 The present invention is a schematic diagram of a process flow corresponding to the ring removal device;

[0046] Figures 3 to 9 1 is a schematic structural diagram corresponding to a wafer ring removal device according to an embodiment of the present invention;

[0047] Figure 10 1 is a flow chart of a ring removal method corresponding to a wafer ring removal device according to an embodiment of the present invention;

[0048] Figure 11 1 is a schematic diagram showing the positional relationship between the center of a wafer and the center of a wafer substrate according to an embodiment of the present invention;

[0049] Figure 12 Schematic diagram of a wafer ring removal device according to an embodiment of the present invention, showing the separation of the thinned wafer body and the thinned ring after the ring is removed. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0051] As known from the background technology, in the process of removing the ring, there is a problem that the wafer is scratched by the ring removing unit. Figure 1 The wafer ring removal device is used to analyze the reasons why the wafer is scratched.

[0052] refer to Figure 1 , is a structural diagram of a ring removal device; the wafer ring removal device includes: a carrier 101, an adsorption hole 102 located on the carrier; a ring removal clamp 106, the ring removal clamp 106 includes a first clamp 107 and a second clamp 108; the relative position of the ring removal clamp 106 and the carrier 101 is fixed.

[0053] The wafer 103 includes a thinned wafer body 104 and a thinning ring 105 separated from the thinned wafer body 104 . Mark 109 is a boundary line after the thinned wafer body 104 and the thinning ring 105 are separated.

[0054] refer to Figure 2 , is a schematic diagram of a process flow corresponding to ring removal by a ring removal device; the ring removal steps of the wafer ring removal device are as follows:

[0055] Step S01: placing a wafer on a carrier.

[0056] The wafer 103 to be removed is placed on the carrier 101, and the relative position of the wafer 103 to be removed and the carrier 101 is manually adjusted. Then, the thinned wafer body 104 of the wafer 103 to be removed is adsorbed on the carrier 101 through the adsorption holes 102 on the carrier 101.

[0057] Step S02: The ring-removing jaws remove the thinned ring.

[0058] The sidewall of the thinned ring 105 is clamped by the first clamping jaw 107 and the second clamping jaw 108 of the ring removing clamping jaw 106 , and the thinned ring 105 is removed from the wafer 103 .

[0059] During the above-mentioned process, the wafer 103 to be removed is manually placed on the carrier 101, and the relative position of the wafer 103 to be removed and the carrier 101 is manually adjusted. There is a situation where the relative position deviation of the wafer 103 to be removed and the carrier 101 is relatively large. Since the relative position of the ring removal clamp 106 and the carrier 101 is fixed, the first clamp 107 and the second clamp 108 will touch the surface of the thinning ring 105, causing the thinning ring 105 to be scratched and unable to be removed, or the first clamp 107 or the second clamp 108 will touch the surface of the thinned wafer body 104, causing the thinned wafer body 104 to be scratched.

[0060] In response to the above technical problems, an embodiment of the present invention provides a wafer ring removal device, which can reduce the risk of the ring removal unit scratching the wafer during the ring removal process.

[0061] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the following will be combined with the embodiments of the present invention. Figures 3 to 9 , the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0062] refer to Figures 3 to 9 , is a schematic structural diagram corresponding to a wafer ring removal device according to an embodiment of the present invention.

[0063] The wafer ring removal device described in this embodiment performs a ring removal operation on the wafer; the wafer includes: a thinned wafer body and a thinning ring surrounding the thinned wafer body; the wafer ring removal device includes: a ring removal unit, used to separate the thinned wafer body and the thinning ring, and remove the thinning ring; a scanning unit, used to determine the position of the wafer base for placing the wafer, and the first relative position of the thinning ring relative to the center of the wafer base; a calculation unit, used to calculate the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base; a control unit, which adjusts the relative position of the ring removal unit and the thinning ring according to the second relative position, and controls the ring removal unit.

[0064] When the wafer ring removal device described in the present invention is used to remove the ring, the calculation unit calculates the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the position and the first relative position of the wafer base obtained by the scanning unit, that is, calculates the offset between the center of the thinned wafer body and the center of the wafer base; the control unit adjusts the relative position of the ring removal unit and the thinning ring according to the offset, controls the ring removal unit to remove the ring, and reduces the risk of the ring removal unit scratching the wafer.

[0065] refer to Figure 3 The wafer includes a thinned wafer body 201 and a thinning ring 202 surrounding the thinned wafer body 201 .

[0066] It should be noted that Figure 3 Marks E3 and E4 in FIG. 2 are boundaries after the thinned wafer body 201 and the thinning ring 202 are separated.

[0067] A plurality of semiconductor devices (not shown) are distributed on the thinned wafer body 201 ; the thinning ring 202 surrounds the thinned wafer body 201 to enhance the strength of the thinned wafer body 201 and reduce the risk of the thinned wafer body 201 being broken during transportation.

[0068] refer to Figure 4 , combined with Figure 3 The ring removal device includes: a bracket 300 that can move relative to the wafer base 301; the bracket 300 is used to carry the ring removal unit 303 and the rough alignment unit 400. Figure 4 For detailed description of the ring removal unit 303 and the coarse alignment unit 400, please refer to the following.

[0069] The number of the brackets 300 is at least one; the material of the brackets 300 includes: metal material (such as stainless steel, aluminum, etc.) or anti-static plastic material (such as polycarbonate, electro-polypropylene, acrylic, etc.); the bracket 300 is composed of a columnar structure, and the columnar structure includes any of the following: a cylindrical structure, an elliptical cylindrical structure, a square cylindrical structure, etc. The embodiment of the present application does not limit the number, material and specific main structure of the brackets 300, and those skilled in the art can adjust the settings according to actual conditions. It should be noted that, for the sake of simplicity and clarity of the drawings and convenience of description, in this embodiment, the number of the brackets 300 is one, the material of the brackets 300 is metal, and the brackets 300 are cylindrical structures.

[0070] The support 300 includes an area 500, an area 501, and an area 503. The ring removal unit 303 is connected to the area 500 of the support 300, and the coarse alignment unit 400 is connected to the area 501 of the support 300.

[0071] It should be noted that, for the sake of clarity of the drawings and convenience of description, the present invention sets the areas 500, 501, and 503. In other embodiments, the areas 500, 501, and 503 may not be set.

[0072] In this embodiment, the region 503 of the support 300 is parallel to the surface of the wafer, and the region 500 and the region 501 are perpendicular to the region 503 .

[0073] The support can move relative to the wafer base, that is, in this embodiment, the support 300 can move relative to the wafer base 301 .

[0074] It should be noted that in some embodiments, the wafer base 301 is fixed, and the support 300 can move in a direction parallel to the surface of the wafer base 301, such as forward and backward, and can also move perpendicular to the surface of the wafer base 301, such as forward and backward; in another embodiment, the support 300 is fixed, and the wafer base 301 can move in a direction parallel to the region 503 of the support 300, such as forward and backward, and can also move perpendicular to the region 503 of the support 300, such as forward and backward; in other embodiments, the wafer base 301 and the support 300 can move simultaneously, for example: when the wafer base 301 moves toward the support 300, the support 300 can move away from or toward the wafer base 301. For another example: when the support 300 moves toward the wafer base 301, the wafer base 301 can move away from or toward the support 300. In this embodiment, the wafer base 301 is fixed, and the bracket 300 can move relative to the wafer base 301, that is, the bracket 300 can move forward and backward in a direction perpendicular to the surface of the wafer base 301, and can also move forward and backward in a direction parallel to the surface of the wafer base 301.

[0075] Continue to refer Figure 3 , the wafer base 301 is used to support the thinned wafer body 201;

[0076] The material of the wafer base 301 includes: metal material (such as stainless steel, aluminum, etc.) or anti-static plastic material (such as polycarbonate, electro-propylene, acrylic, etc.); the wafer base 301 is a cylindrical structure, and the cylindrical structure includes any of the following: a cylindrical structure, an elliptical cylindrical structure, a square cylindrical structure, etc. The embodiment of the present application does not limit the material and specific cylindrical structure of the wafer base 301, and those skilled in the art can adjust the settings according to actual conditions. In this embodiment, the material of the wafer base 301 is metal, and the wafer base 301 is a cylindrical structure.

[0077] The carrier 302 is used to carry the wafer base 301, the circular cutting tape and the circular cutting tape frame.

[0078] The wafer ring removal device includes: a ring removal unit, which is used to separate the thinned wafer body and the thinning ring, and remove the thinning ring.

[0079] The ring removal unit includes: a ring removal claw capable of grabbing the thinned ring; at least three first connecting rods, one end of each first connecting rod is movably connected to the bracket, and the other end of each first connecting rod is rotatably connected to a ring removal claw; wherein, the first connecting rods are evenly distributed around the bracket.

[0080] It should be noted that the ring removal unit can move on the bracket in a radial direction parallel to the wafer, or can move perpendicular to the surface of the wafer.

[0081] refer to Figure 5 and Figure 6 , combined with Figure 3 and Figure 4 The ring removal unit 303 includes: a ring removal claw, which can grab the thinned ring 202.

[0082] The number of the ring removal jaws is at least 3. In this embodiment, the number of the ring removal jaws is 3, namely, the ring removal jaw 304, the ring removal jaw 305, and the ring removal jaw 306. Figure 6 shown.

[0083] The cross-sectional shape of the ring-removing clamp on a plane perpendicular to the wafer base is in the shape of an "I".

[0084] In this embodiment, the cross-sectional shapes of the ring removal jaws 304 , 305 and 306 on a plane perpendicular to the wafer base 301 are all in the shape of an I.

[0085] For the sake of simplicity and convenience of description, Figure 3 and Figure 5 Only the ring removal jaws 304 and 305 are shown, but the present invention is not limited thereto.

[0086] The cross-section of the ring-removing clamp on a plane perpendicular to the wafer base includes a separated first layer, a second layer and a connecting member, and the connecting member vertically connects the first layer and the second layer; wherein the width of the first layer and / or the second layer that can contact the thinning ring is [1 / 3, 1) of the width of the thinning ring.

[0087] It should be noted that the width of the first layer and / or the second layer that can contact the thinning ring is [1 / 3, 1) of the width of the thinning ring, which includes the following three meanings: the first: the width of the first layer and the second layer that can contact the thinning ring is both [1 / 3, 1) of the width of the thinning ring; the second: the width of the first layer that can contact the thinning ring is [1 / 3, 1) of the width of the thinning ring; the third: the width of the second layer that can contact the thinning ring is [1 / 3, 1) of the width of the thinning ring.

[0088] Continue to refer Figure 3 、 Figure 4 and Figure 5In this embodiment, the ring removal clamp 304 is used as an example for description. For other ring removal clamps, reference can be made to the description of the ring removal clamp 304. The cross-section of the ring removal clamp 304 on a plane perpendicular to the wafer base 301 includes a separated first layer 307, a second layer 308, and a connector 309. The connector 309 vertically connects the first layer 307 and the second layer 308. The width w1 of the contact between the first layer 307 and / or the second layer 308 and the thinning ring 202 is [1 / 3, 1] of the width w2 of the thinning ring 202.

[0089] It should be noted that the width w1 of the contact between the first layer 307 and the thinning ring 202 is greater than or equal to 1 / 3 times the width w2 of the thinning ring 202, which reduces the risk of the thinning ring 202 slipping off the first layer 307 during the ring removal process; the width w1 of the contact between the first layer 307 and the thinning ring 202 is less than 1 times the width w2 of the thinning ring 202, which reduces the risk of the ring removal clamp hitting the thinning ring 202 during the ring removal process.

[0090] It should be noted that the width w3 of the second layer 308 that can contact the thinned ring 202 is greater than or equal to 1 / 3 times the width w2 of the thinned ring 202. During the ring removal process, the thinned ring 202 is prevented from bouncing off the first layer 307. The width w3 of the second layer 308 that can contact the thinned ring 202 is less than 1 times the width of the thinned ring 202. During the ring removal process, the risk of the second layer 308 colliding with the thinned ring 202 is reduced. During the ring removal process, the second layer 308 can control the thinned ring 202 to be located between the first layer 307 and the second layer 308.

[0091] In this embodiment, the width w4 of the first layer 307 and the second layer 308 are equal.

[0092] The connection position between the connecting member 309 and the first layer 307 and the second layer 308 is the geometric center of the first layer 307 and the second layer 308, which helps to prevent the ring removal clamp from being eccentric when rotating around the area 500 of the bracket 300.

[0093] The contact end between the ring-removing clamp and the thinned ring includes one or more of a square cylinder, a circular cylinder, an elliptical cylinder, and a cone.

[0094] refer to Figure 7 , combined with Figure 6 , Figure 7 include Figure 7 (a) Figure 7 (b) Figure 7 (c) and Figure 7 (d).

[0095] like Figure 7 As shown in (a), the first layer 307 of the ring removal clamp is in the form of a square column with the contact end 310 of the thinned ring 202.

[0096] like Figure 7 As shown in (b), the first layer 307 of the ring-removing jaws is conical, i.e., pointed, with the contact end 310 of the thinning ring 202. When removing the ring, the pointed end of the first layer 307 can easily enter the gap between the thinning ring 202 and the ring-cutting tape, which is beneficial for separating the thinning ring 202 and the ring-cutting tape.

[0097] like Figure 7 As shown in (c), the first layer 307 of the ring removal clamp is in the form of a circular cylinder or an elliptical cylinder, i.e., an arc-shaped protrusion, which facilitates the arc-shaped protrusion of the first layer 307 to enter the gap between the thinning ring 202 and the ring cutting tape when removing the ring, thereby facilitating the separation of the thinning ring 202 and the ring cutting tape. In addition, compared to Figure 7 The pointed and arc-shaped protrusions in (b) can prevent the tip of the ring-removing jaw from piercing and breaking the ring-cutting tape, resulting in uneven force on the thinned ring 202 at the ring-removing jaws 304, 305 and 306, causing the thinned ring 202 to break.

[0098] like Figure 7 As shown in (d), the first layer 307 of the ring removal clamp is set to a wavy or serrated bottom, which reduces the contact area between the bottom of the first layer 307 and the cutting tape. When removing the ring, the cutting tape is prevented from adhering to the bottom of the first layer 307, affecting the ring removal efficiency.

[0099] Continue to refer Figure 3 and Figure 5 The ring removal unit 303 further includes: a pressure sensing module 311, which is arranged on the ring removal clamp in a one-to-one correspondence and is used to test the force exerted by the ring removal clamp on the wafer.

[0100] The pressure sensing module 311 is disposed on the connecting member 309 between the first layer 307 and the second layer 308 , and is located on the side of the first layer 307 that contacts the thinning ring 202 .

[0101] In this embodiment, the pressure sensing module 311 is provided on the connecting piece 309 on the ring removal clamp 304, the ring removal clamp 305 and the ring removal clamp 306. The pressure sensing module on the connecting piece 309 on the ring removal clamp 306 is not shown.

[0102] The one-to-one correspondence is set on the ring-removing jaws, that is, the number of pressure sensing modules 311 is equal to that of the ring-removing jaws, and one pressure sensing module 311 corresponds to one ring-removing jaw; the pressure sensing module 311 is used to test the force of the ring-removing jaws acting on the wafer, that is, to test the force of the ring-removing jaws acting on the thinning ring 202, and judge whether the force of the ring-removing jaws acting on the thinning ring 202 exceeds the set value according to the pressure sensing module 311; because when removing the ring, there is a possibility that the ring-removing jaws squeeze the thinning ring 202, and the squeezed thinning ring 202 squeezes the thinned wafer body 201; for example, when the force of the ring-removing jaws acting on the thinning ring 202 exceeds the set value, after the ring is removed, it is necessary to detect whether there is a crack on the edge of the thinned wafer body 201 to prevent it from flowing into the next process, thereby saving the production cycle.

[0103] The ring removal unit also includes: at least 3 first connecting rods, one end of each first connecting rod is movably connected to the bracket, and the other end of each first connecting rod is rotatably connected to a ring removal clamp; wherein, the first connecting rods surround the bracket and are evenly distributed.

[0104] Continue to refer Figure 6 In this embodiment, the number of the first connecting rods is three, namely the first connecting rod 315, the first connecting rod 316, and the first connecting rod 317.

[0105] One end of each first connecting rod is movably connected to the bracket. In this embodiment, that is, the bracket 300 is perpendicular to the wafer surface. Along the radial direction of the wafer, the first connecting rod 315, the first connecting rod 316, and the first connecting rod 317 can all be extended and contracted. When removing the ring, on the one hand, it is convenient to adjust the relative position of the ring removal clamp and the wafer base, reducing the risk of the ring removal unit scratching the wafer. On the other hand, it can adapt to the removal of rings of different wafer sizes.

[0106] The other end of each first connecting rod is rotatably connected to a ring removal clamp. In this embodiment, the other end of the first connecting rod 315 is rotatably connected to the ring removal clamp 304, the other end of the first connecting rod 316 is rotatably connected to the ring removal clamp 305, and the other end of the first connecting rod 317 is rotatably connected to the ring removal clamp 306.

[0107] Continue to refer Figure 5 and Figure 6 , taking the first connecting rod 315 and the ring retrieval claw 304 as an example, the other end of the first connecting rod 315 is rotatably connected to the ring retrieval claw 304. For other first connecting rods rotatably connected to the ring retrieval claw, reference can be made to the description of the rotatable connection between the first connecting rod 315 and the ring retrieval claw 304.

[0108] The first connecting rod 315 includes an area 318 and an area 319, and the area 318 and the area 319 are vertically connected. The ring removal clamp 304 rotates around the area 319 with the area 319 as the axis. The rotation direction F can be clockwise or counterclockwise. In this embodiment, the rotation direction F is clockwise. Figure 6 The following beneficial effects are achieved: when the ring removal jaws 304 encounter the thinning ring 202, the ring removal jaws 304 are rotatably connected to the first connecting rod 315, thereby reducing the probability of the ring removal jaws 304 damaging and / or breaking the thinning ring 202 compared to a case where the ring removal jaws 304 are fixedly connected to the first connecting rod 315. This reduces the risk of the ring removal unit scraping the wafer.

[0109] Continue to refer Figure 6 The first connecting rods are evenly distributed around the bracket, that is, the angles between the first connecting rods 315 and 316, the angles between the first connecting rods 316 and 317, and the angles between the first connecting rods 317 and 315 are equal, so that the forces exerted by the first connecting rods 315, 316, and 317 on the thinning ring 202 are uniform, thereby reducing the risk of the ring removal unit scraping the wafer.

[0110] Continue to refer Figure 6 The wafer ring removal device includes: a scanning unit 320 for determining the position of the wafer base 301 for placing the wafer, and a first relative position of the thinning ring 202 relative to the center of the wafer base 301.

[0111] The scanning unit 320 is configured to determine the position of the wafer base 301 on which the wafer is placed. That is, the scanning unit 320 determines the center of the wafer base 301. The scanning unit 320 is configured to determine a first relative position of the thinning ring 202 relative to the center of the wafer base 301. That is, the scanning unit 320 uses the center of the wafer base 301 as a reference point and scans to obtain the distance between the edge of the thinning ring 202 and the center of the wafer base 301. This distance is the first relative position.

[0112] Continue to refer Figure 4 and Figure 6 The scanning unit includes: a second connecting rod 321, one end of which is movably connected to the bracket 300; a light sensor 322, which is connected to the other end of the second connecting rod 321 and is used to obtain the position of the thinning ring 202; wherein the light sensor 322 is coupled to the computing unit 323 to transmit the position of the thinning ring 202 obtained by the light sensor 322 to the computing unit 323.

[0113] In this embodiment, one end of the second connecting rod 321 is movably connected to the bracket 300 , that is, one end of the second connecting rod 321 is movably connected to the bracket 300 through the area 500 of the bracket 300 .

[0114] The area 503 of the bracket 300 is parallel to the wafer surface, and one end of the second connecting rod 321 is movably connected to the bracket 300 along the radial direction parallel to the wafer, that is, the second connecting rod 321 can be extended and contracted along the direction parallel to the wafer surface to adapt to wafer rings of different sizes.

[0115] In this embodiment, the optical sensor 322 is connected to the other end of the second connecting rod 321 and is used to obtain the position of the thinning ring 202, wherein the optical sensor 322 is coupled to the computing unit, that is, the scanning unit controls the optical sensor 322 to move along the edge of the thinning ring 202 to obtain the distance between the edge of the thinning ring 202 and the center of the wafer base 301, that is, the first relative position, and the optical sensor 322 is coupled to the computing unit to transmit the first relative position to the computing unit.

[0116] Continue to refer Figure 6 The wafer ring removal device includes: a calculation unit 323, which is used to calculate the second relative position of the center of the thinned wafer body 201 relative to the center of the wafer base 301 based on the first relative position and the position of the wafer base 301.

[0117] That is, the calculation unit 323 calculates the center of the wafer base 301 according to the position of the wafer base 301, and the calculation unit 323 calculates the center position of the thinned wafer body 201 according to the first relative position. The calculation unit 323 calculates the second relative position of the center of the thinned wafer body 201 relative to the center of the wafer base 301 according to the center of the wafer base 301 and the center of the thinned wafer body 201. The second relative position is the distance that the center of the thinned wafer body 201 deviates from the center of the wafer base 301.

[0118] Continue to refer Figure 3 、 Figure 4 and Figure 6 The wafer ring removal device includes: a control unit (not shown) that adjusts the relative position of the ring removal unit 303 and the thinning ring 202 according to the second relative position, and controls the ring removal unit 303.

[0119] That is, the control unit adjusts the relative position of the ring taking unit 303 and the thinning ring 202, and adjusts the opening angle of the ring taking claws 304, 305, and 306 in the ring taking unit according to the distance that the center of the thinned wafer body 201 deviates from the center of the wafer base 301; the control unit controls the opened ring taking claws 304, 305, and 306 to move closer to the thinning ring 202, so that the ring taking claws 304, 305, and 306 are closer to the thinning ring 202. , the ring removing jaws 306 clamp the thinning ring 202, that is, the thinning ring 202 is clamped between the ring removing jaws 304, the ring removing jaws 305, and the first layer 307 and the second layer 308 of the ring removing jaws 306; along the direction perpendicular to the wafer surface, the control unit controls the ring removing jaws 304, the ring removing jaws 305, and the ring removing jaws 306 that clamp the thinning ring 202 to move away from the wafer, so as to remove the thinning ring 202 from the wafer, so as to remove the thinning ring 202, thereby reducing the risk of the ring removing unit scratching the wafer.

[0120] It should be noted that the opening angles of the ring removal jaws 304, 305 and 306 in the ring removal unit are adjusted, that is, the ring removal jaws 304 and 305 are moved in a direction parallel to the wafer surface so that the ring removal jaws 304 and 305 do not touch the wafer to be removed.

[0121] The wafer ring removal device includes a coarse alignment unit, the coarse alignment unit including a third connecting rod, one end of which is connected to the bracket; and a coarse alignment clamp connected to the other end of the third connecting rod, configured to place the wafer on the wafer base so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error. Specifically, the coarse alignment unit is configured to roughly align the center of the wafer with the center of the wafer base to prevent excessive positional deviation of the wafer on the wafer base, which could cause the thinning ring to shift onto the wafer base, reducing the efficiency of the ring removal unit or even preventing the ring removal unit from being able to remove the ring.

[0122] Continue to refer Figure 4 The wafer ring removal device includes a coarse alignment unit 400, which is movably connected to the support 300 via a region 501 of the support 300. The movably connected means that the coarse alignment unit 400 is movable in a direction parallel to the wafer surface and in a direction perpendicular to the wafer surface.

[0123] refer to Figure 8 and Figure 9 , combined with Figure 4The coarse alignment unit 400 includes: a third connecting rod, one end of which is connected to the bracket; the number of the third connecting rods is at least 3, and a coarse alignment clamp connected to the other end of the third connecting rod, which is used to place the wafer on the wafer base and make the distance between the center of the wafer and the center of the wafer base within a preset alignment error. The number of the coarse alignment clamps is at least 3, which reduces the risk of the ring removal unit scratching the wafer.

[0124] It should be noted that Figure 9 Marks E1 and E2 in FIG. 1 are boundaries after the thinned wafer body 201 and the thinning ring 202 are separated.

[0125] In this embodiment, there are three third connecting rods, namely, third connecting rod 401, third connecting rod 402, and third connecting rod 403. There are three coarse alignment jaws, namely, coarse alignment jaw 404, coarse alignment jaw 405, and coarse alignment jaw 406. One end of the third connecting rod 401 is connected to the bracket 300 via region 501 of the bracket 300, and the other end of the third connecting rod 401 is connected to the coarse alignment jaw 404. One end of the third connecting rod 402 is connected to the bracket 300 via region 501 of the bracket 300, and the other end of the third connecting rod 402 is connected to the coarse alignment jaw 405. One end of the third connecting rod 403 is connected to the bracket 300 via region 501 of the bracket 300, and the other end of the third connecting rod 403 is connected to the coarse alignment jaw 406.

[0126] It should be noted that, in this embodiment, the relevant settings of the coarse alignment clamp can refer to the ring removal clamp, which will not be described in detail here.

[0127] Continue to refer Figure 3 The wafer ring removal device includes: a cutting tape 601 for bonding the wafer; a cutting tape frame 600 for removing the cutting tape 601, and the cutting tape frame 600 is located on the edge area of ​​the cutting tape 601; wherein, the wafer after bonding is located on the central area of ​​the cutting tape 601, and there is a gap between the wafer and the cutting tape frame 600 to prevent the cutting tape frame 600 from damaging the wafer during the ring removal process.

[0128] The circular cutting tape 601 includes an ultraviolet irradiation tape or a heat-sensitive tape.

[0129] The circular dicing tape 601 covers the entire surface of the wafer base 301 and extends to the carrier 302 outside the wafer base 301 .

[0130] The wafer ring removal device includes: a motor (not shown) coupled to the coarse alignment clamp and the ring removal clamp, and the control unit controls the motor to drive the coarse alignment clamp and the ring removal clamp to move.

[0131] The control unit controls the motor to drive the coarse alignment jaws to clamp the wafer and to move the coarse alignment jaws behind the wafer so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error, thereby achieving coarse alignment of the wafer and the wafer base. The control unit controls the motor to drive the ring removal jaws to clamp the thinning ring and to move the ring removal jaws behind the wafer in a direction perpendicular to the wafer surface and away from the wafer to remove the thinning ring.

[0132] Continue to refer Figure 8 The motor is coupled to the coarse alignment jaw 404, the coarse alignment jaw 405, and the coarse alignment jaw 406. The control unit controls the motor to drive the coarse alignment jaw 404, the coarse alignment jaw 405, and the coarse alignment jaw 406 to move to achieve coarse alignment of the wafer and the wafer base.

[0133] Continue to refer Figure 6 The motor is coupled to the ring removal claw 305, the ring removal claw 304, and the ring removal claw 306. The control unit controls the motor to drive the ring removal claw 305, the ring removal claw 304, and the ring removal claw 306 to move to achieve removal and thinning.

[0134] In order to solve the technical problem, accordingly, an embodiment of the present invention further provides a wafer ring removal method, which is applied to a wafer ring removal device; Figure 10 FIG. 1 is a flow chart of a wafer ring removal method according to an embodiment of the present invention.

[0135] refer to Figures 3 to 9 The wafer includes: a thinned wafer body 201 and a thinning ring 202 surrounding the thinned wafer body 201; the wafer ring removal device includes: a ring removal unit 303, a scanning unit 320, a calculation unit 323, and a control unit.

[0136] The wafer ring removal device further includes: a rough alignment unit 400, a ring-cutting tape 601, and a ring-cutting tape frame 600. The rough alignment unit 400 includes: a rough alignment clamp.

[0137] The wafer ring removal device further includes: a motor, a light sensor 322, and a ring removal clamp.

[0138] In this embodiment, the number of the ring removal jaws is 3, namely, the ring removal jaw 304, the ring removal jaw 305, and the ring removal jaw 306. Figure 6As shown; the number of coarse alignment jaws is 3, namely coarse alignment jaws 404, coarse alignment jaws 405, coarse alignment jaws 406, as Figure 8 shown.

[0139] In this embodiment, for the specific description of the ring removal unit 303, scanning unit 320, calculation unit 323, control unit, coarse alignment unit 400, coarse alignment clamp, circular cutting tape 601, circular cutting tape frame 600, motor, light sensor 322, ring removal clamp, etc., please refer to the description of the wafer ring removal device in the previous embodiment and will not be elaborated here.

[0140] The ring removal method includes: the ring removal method includes: adsorbing the wafer with the ring cutting tape bonded thereto onto the wafer base; using the scanning unit to determine the position of the wafer base for placing the wafer, and the first relative position of the thinning ring relative to the center of the wafer base; using the calculation unit to calculate the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base; using the control unit to adjust the relative position of the ring removal unit and the thinning ring based on the second relative position, control the ring removal unit to separate the thinned wafer body and the thinning ring, and remove the thinning ring.

[0141] Before the step of placing the wafer with the ring cutting tape bonded thereto on the wafer base, the ring removal method further includes: using the control unit to adjust the position of the wafer and the wafer base through the coarse alignment clamps of the coarse alignment unit so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error.

[0142] refer to Figure 10 and Figure 11 , combined with Figures 3 to 9 ;in Figure 11 Schematic diagram of the positional relationship between the center of the wafer and the center of the wafer base according to an embodiment of the present invention. The process of the wafer ring removal method mainly includes the following steps:

[0143] Step S11: using the control unit to adjust the positions of the wafer and the wafer base through the coarse alignment jaws of the coarse alignment unit so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error.

[0144] refer to Figure 8 、 Figure 9In this embodiment, the control unit controls the motor to drive the coarse alignment jaws 404, coarse alignment jaws 405, and coarse alignment jaws 406 to clamp the wafer together, and drives the coarse alignment jaws 404, coarse alignment jaws 405, and coarse alignment jaws 406 after clamping the wafer to move in a direction parallel to and / or perpendicular to the wafer surface to adjust the position of the wafer and the wafer base 301, so that the distance between the center of the wafer (i.e., the center of the wafer) and the center of the wafer base 301 is within a preset alignment error, so as to achieve coarse alignment of the wafer and the wafer base 301, prevent the alignment error between the wafer and the wafer base 301 from being too large, resulting in the subsequent inability to remove the ring or difficulty in removing the ring, and increase the risk of the ring removal jaws 304, 305, and 306 hitting the thinned wafer body 201 and / or the thinning ring 202 to cause the wafer to be scratched or broken, that is, reduce the risk of the ring removal unit scratching the wafer.

[0145] Typically, a first alignment mark (not shown) is designed on the wafer base 301, and a second alignment mark (not shown) is designed on the wafer. By fitting the first alignment mark and the second alignment mark, the wafer and the wafer base 301 are aligned.

[0146] Step S12: adsorbing the wafer with the dicing tape on the wafer base.

[0147] continue Figure 8 、 Figure 9 In this embodiment, after the first alignment mark and the second alignment mark are fitted together, the control unit controls the motor to drive the coarse alignment jaws 404, 405, and 406 that clamp the wafer to move in a direction perpendicular to the surface of the wafer, and place the wafer with the dicing tape on the wafer base so that the dicing tape contacts the wafer base and the carrier. The adsorption holes (not shown) of the wafer base adsorb the wafer with the dicing tape on the wafer base, and at the same time, the adsorption holes located on the carrier adsorb the dicing tape located outside the wafer base on the carrier.

[0148] Step S13: Using the scanning unit, determine the position of the wafer base for placing the wafer, and the first relative position of the thinning ring relative to the center of the wafer base, and using the calculation unit, calculate the second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base.

[0149] In this embodiment, the following sequence is followed: determining the center of the wafer base 301 , calculating the center of the thinned wafer body 201 based on the first relative position, and determining the second relative position based on the center of the wafer base 301 and the center of the thinned wafer body 201 .

[0150] The center of the wafer pedestal 301 is determined as follows:

[0151] refer to Figure 11 , combined with Figure 3 The scanning unit controls the optical sensor 322 to move along the edge 800 of the wafer base 301 to obtain the position of the edge 800 of the wafer base 301 and provide data for calculating the center of the wafer base.

[0152] Continue to refer Figure 11 , combined with Figure 3 In this embodiment, to improve production efficiency, the scanning unit evenly scans three points on the edge 800 of the wafer base 301, such as point A (X1, Y1), point B (X2, Y2), and point C (X3, Y3), along the edge 800 of the wafer base 301. The calculation unit calculates the center M1 of the wafer base 301 based on the positions of the three points on the edge 800 of the wafer base 301 obtained by the scanning unit. That is, the scanning unit is used to determine the position of the wafer base 301 for placing the wafer. In other embodiments, more than three points can be selected. The more points selected for scanning, the more accurately the center M1 of the wafer base 301 obtained by the calculation unit, and the lower the risk of the ring removal unit scratching the wafer.

[0153] The center of the thinned wafer body 201 is calculated according to the first relative position, and the process is as follows:

[0154] Taking the center M1 of the wafer base 301 as a reference point, the scanning unit controls the light sensor 322 to move along the edge 801 of the wafer to obtain the position of the edge 801 of the wafer, that is, to obtain the first relative position of the thinning ring 202 relative to the center M1 of the wafer base 301, and provide data for calculating the center of the thinned wafer body 201.

[0155] Continue to refer Figure 11 , combined with Figure 3 In this embodiment, in order to improve production efficiency, the scanning unit evenly scans three points on the edge 801 of the wafer along the edge of the wafer, such as point D (X4, Y4), point E (X5, Y5), and point F (X6, Y6), that is, obtains the first relative position of the thinning ring 202 relative to the center M1 of the wafer base 301. The calculation unit calculates the center M2 of the thinned wafer body 201 based on the first relative position, that is, based on the three points on the wafer edge 801 obtained by the scanning unit. In other embodiments, more than three points can be selected. The more points are selected for scanning, the more accurate the center M2 of the thinned wafer body 201 obtained by the calculation unit, and the lower the risk of the ring removal unit scratching the wafer.

[0156] The second relative position is determined based on the center of the circular base 301 and the center of the thinned wafer body 201, and the process is as follows:

[0157] The calculation unit calculates the distance between the center M1 and the center M2 based on the center M1 of the wafer base 301 (i.e., the position of the wafer base 301) and the center M2 of the thinned wafer body 201, and obtains the second relative position of the center M2 of the thinned wafer body 201 relative to the center M1 of the wafer base 301, that is, calculates the distance that the thinned wafer body 201 deviates from the wafer base 301.

[0158] Step S14: using the control unit to adjust the relative position of the ring removing unit and the thinning ring according to the second relative position, controlling the ring removing unit to separate the thinned wafer body and the thinning ring, and removing the thinning ring.

[0159] Continue to refer Figure 11 , combined with Figure 3 and Figure 6 In this embodiment, the control unit controls the motor to drive the ring removal unit 303 to move relative to the wafer along a direction perpendicular to and / or parallel to the wafer surface based on the second relative position of the center M2 of the thinned wafer body 201 relative to the center M1 of the wafer base 301, so as to adjust the relative positions of the ring removal jaws 304, 305, and 306 of the ring removal unit 303 and the thinning ring 202.

[0160] The control unit adjusts the opening angles of the ring removal jaws 304, 305, 306 according to the relative positions of the ring removal jaws 304, 305, 306 and the thinning ring 202, so that the ring removal jaws 304, 305, 306 can clamp the wafer.

[0161] The control unit controls the motor to drive the ring removal jaws 304, 305, and 306 that clamp the wafer to move in a direction perpendicular to and away from the wafer surface to remove the thinning ring 202 from the wafer, that is, to control the ring removal unit 303 to separate the thinned wafer body 201 and the thinning ring 202 to remove the thinning ring 202.

[0162] refer to Figure 12 , is a schematic diagram of the separation of the thinned wafer body and the thinning ring after the ring is removed by the wafer ring removal device according to an embodiment of the present invention, that is, a schematic diagram of the separation of the thinned wafer body 201 and the thinning ring 202.

[0163] It should be noted that the reference Figure 11When the distance between the ring removal jaws 305 and the wafer base 301 is less than or equal to the second relative position d1, the ring removal process stops to reduce the risk of the ring removal jaws 305 striking the thinning ring 202. The wafer needs to be removed from the wafer base 301, and steps S11 to S14 are repeated. The distance between the ring removal jaws 305 and the wafer base 301 is the distance between the ring removal jaws 305 and the wafer base 301 when the ring removal jaws 305 are at their maximum angle.

[0164] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solutions of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the scope of protection of the technical solutions of the present invention.

Claims

1. A wafer ring removal device, characterized in that: The ring removing device performs a ring removing operation on the wafer; The wafer comprises: a thinned wafer body and a thinning ring surrounding the thinned wafer body; the ring removal device comprises: a ring removing unit, configured to separate the thinned wafer body and the thinning ring, and remove the thinning ring; a scanning unit for determining a position of a wafer base for placing the wafer and a first relative position of the thinning ring relative to a center of the wafer base; a calculation unit, configured to calculate a second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base; The control unit adjusts the relative position between the ring removing unit and the thinning ring according to the second relative position, and controls the ring removing unit.

2. The ring removal device according to claim 1, characterized in that: Also includes: a support, movable relative to the wafer base; The ring removal unit comprises: a ring-taking gripper capable of grasping the thinned ring; at least three first connecting rods, one end of each first connecting rod being movably connected to the bracket, and the other end of each first connecting rod being rotatably connected to a ring removal clamp; Wherein, the first connecting rods surround the bracket and are evenly distributed.

3. The ring removal device according to claim 2, characterized in that: The scanning unit includes: a second connecting rod, one end of which is movably connected to the bracket; a light sensor connected to the other end of the second connecting rod and used to obtain the position of the thinning ring; The light sensor is coupled to the computing unit.

4. The ring removal device according to claim 2, characterized in that: Also includes: coarse alignment unit; The coarse alignment unit includes: a third connecting rod, one end of which is connected to the bracket; A coarse alignment clamp is connected to the other end of the third connecting rod and is used to place the wafer on the wafer base so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error.

5. The ring removal device according to claim 2, characterized in that: The cross-sectional shape of the ring-removing clamp on a plane perpendicular to the wafer base is in the shape of an "I".

6. The ring removal device according to claim 5, characterized in that: Also includes: The contact end between the ring-removing clamp and the thinned ring includes one or more of a square cylinder, a circular cylinder, an elliptical cylinder, and a cone.

7. The ring removal device according to claim 1, characterized in that: Also includes: Circular cutting tape, used for bonding crystal circles; a circular cutting tape frame for removing the circular cutting tape, the circular cutting tape frame being located on an edge region of the circular cutting tape; The bonded wafer is located on the central area of ​​the dicing tape and is spaced apart from the dicing tape frame.

8. The ring removal device according to claim 2, wherein: The ring removal unit further includes: a pressure sensing module, which is arranged on the ring removal clamps in a one-to-one correspondence and is used to test the force exerted by the ring removal clamps on the wafer.

9. The ring removal device according to claim 4, characterized in that: Also includes: The motor is coupled to the coarse alignment clamping jaw and the ring-removing clamping jaw, and the control unit controls the motor to drive the coarse alignment clamping jaw and the ring-removing clamping jaw to move.

10. A wafer ring removal method, applied to a wafer ring removal device, characterized in that: The wafer comprises: a thinned wafer body and a thinning ring surrounding the thinned wafer body; The wafer ring removal device includes: Ring taking unit, scanning unit, calculation unit, control unit; The ring removal method comprises: Adsorbing the wafer with the dicing tape on it onto the wafer base; Using the scanning unit, determining a position of a wafer base for placing the wafer and a first relative position of the thinning ring relative to a center of the wafer base; Using the calculation unit, calculate a second relative position of the center of the thinned wafer body relative to the center of the wafer base based on the first relative position and the position of the wafer base; The control unit is used to adjust the relative position of the ring removing unit and the thinning ring according to the second relative position, and control the ring removing unit to separate the thinned wafer body and the thinning ring, and remove the thinning ring.

11. The method for removing the IUD according to claim 10, wherein: The wafer ring removal device further includes: a coarse alignment unit; The coarse alignment unit comprises: a coarse alignment clamping jaw; Before placing the wafer with the dicing tape bonded thereto on the wafer base, the ring removal method further includes: The control unit is used to adjust the positions of the wafer and the wafer base through the coarse alignment clamps of the coarse alignment unit so that the distance between the center of the wafer and the center of the wafer base is within a preset alignment error.

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