Wafer bonding device and wafer bonding method

Abstract

The present invention discloses a wafer bonding device and a wafer bonding method, and relates to the field of wafer production equipment. The wafer bonding device is used to adhere a protective film to a wafer; the wafer bonding device comprises an elastic plate and a support member, the support member is connected to the elastic plate, and the connection point between the support member and the elastic plate is a center point; in the initial state of the elastic plate, the convex arc surface of the elastic plate is used to carry the protective film, and the protective film located at the center point adheres to the center position of the wafer; when the elastic plate is under stress, the elastic plate is separated from the protective film radially from the center point until the protective film is completely attached to the wafer. The wafer bonding device provided by the present invention can perform better bonding processing on the wafer.

Description

Technical Field

[0001] The present invention relates to the field of wafer production equipment, and in particular to a wafer bonding device and a wafer bonding method. Background Art

[0002] At present, when wafers are mounted on the market, a mounting device is usually used to flatten the protective film in advance, and then the protective film is translated and adhered to the wafer while aligning the center point of the wafer.

[0003] During the bonding process of this type of bonding device, it is difficult to completely expel the bubbles between the protective film and the wafer, and the stress conditions at different parts of the protective film vary greatly, resulting in poor bonding uniformity and affecting the wafer bonding effect. Summary of the invention

[0004] The object of the present invention is to provide a wafer bonding device which can perform better bonding processing on wafers.

[0005] Another object of the present invention is to provide a wafer bonding method, which has the characteristic of better wafer bonding effect.

[0006] The embodiment of the present invention provides a technical solution:

[0007] A wafer bonding device, used for bonding a protective film to a wafer, the wafer bonding device comprising an elastic plate and a support member, the support member being connected to the elastic plate, and the connection point between the support member and the elastic plate being a center point;

[0008] When the elastic plate is in an initial state, the convex arc surface of the elastic plate carries the protective film, and the protective film located at the center point adheres to the center position of the wafer;

[0009] When the elastic plate is under stress, the elastic plate is separated from the protective film radially from the center point until the protective film is completely attached to the wafer.

[0010] In an optional embodiment, the elastic plate is made of rubber, and / or

[0011] The elastic plate and the supporting member are integrally formed.

[0012] In an optional embodiment, when the elastic plate is in an initial state, the elastic plate includes a concave arc surface; in any vertical plane where the center point is located, cross-sections of the convex arc surface and the concave arc surface are both arc-shaped.

[0013] In an optional embodiment, with the central point as the center of the circle, the thickness of the elastic plate gradually increases in the radial direction.

[0014] In an optional embodiment, when the elastic plate is in an initial state, the elastic plate includes a concave arc surface; the concave arc surface is concavely provided with a plurality of transition annular grooves, the radii of the circles where the plurality of transition annular grooves are located are different from each other, and the centers of the circles where the plurality of transition annular grooves are located all coincide with the center point.

[0015] In an optional embodiment, when the elastic plate is in an initial state, the elastic plate includes a concave arc surface; the concave arc surface has a plurality of annular steps, the radii of the circles where the plurality of annular steps are located are different from each other, the centers of the circles where the plurality of annular steps are located coincide with the center point, and any one of the annular steps is formed by the increase in radial thickness of the elastic plate.

[0016] In an optional embodiment, the wafer bonding device further includes a gravity member and a lifting platform, the gravity member is connected to the support member, and the lifting platform supports the gravity member to drive the support member to move up and down in a vertical direction.

[0017] In an optional embodiment, the wafer bonding device further includes a gravity ring, and the gravity ring is arranged on the periphery of the protective film located on the elastic plate.

[0018] An embodiment of the present invention further provides a wafer bonding method, which is applied to the aforementioned wafer bonding device, wherein the wafer bonding device comprises an elastic plate and a support member, wherein the support member is connected to the elastic plate, and the connection point between the support member and the elastic plate is the center point; when the elastic plate is in an initial state, the convex arc surface of the elastic plate carries the protective film, and the protective film located at the center point adheres to the center position of the wafer; when the elastic plate is under stress, the elastic plate separates from the protective film radially from the center point until the protective film is completely attached to the wafer. The wafer bonding method comprises:

[0019] Placing a protective film on the convex curved surface of the elastic plate;

[0020] Placing a wafer on the protective film, wherein the center position of the wafer adheres to the protective film at a center point, and the center point is a connection point between the support member and the elastic plate;

[0021] Applying a force to the support member so that the force drives the convex arc surface to separate from the protective film radially from the center point, so that the adhesion area between the protective film and the wafer spreads radially from the center point to the periphery;

[0022] When the wafer is completely adhered to the protective film, stop applying force to the support member.

[0023] In an optional embodiment, after placing the protective film on the convex curved surface of the elastic plate, the wafer bonding method further includes:

[0024] A gravity ring is arranged at the periphery of the protective film to fix the protective film to the convex curved surface;

[0025] Wherein, the radius of the protective film disposed on the convex arc surface is greater than the radius of the wafer.

[0026] Compared with the prior art, the wafer bonding device provided by the present invention, in actual application, places a protective film on the convex arc surface of the elastic plate, and then places the wafer on the protective film, the center position of the wafer is adhered to the protective film and supported by the center point of the elastic plate. By applying a downward force to the support member, the elastic plate is pulled to gradually separate from the protective film from the center point, so that the support part of the elastic plate on the wafer through the protective film diffuses radially from the center point to the periphery, thereby driving the adhesion area of ​​the protective film and the wafer to diffuse radially from the center point to the periphery, achieving uniform bonding of the wafer, and in the process of bonding the wafer and the protective film from the center point to the periphery, the air between the wafer and the protective film can be completely discharged, avoiding the occurrence of a situation where the protective film cannot be stably adhered to the wafer due to the generation of bubbles. Therefore, the beneficial effects of the wafer bonding device provided by the present invention include: being able to perform better bonding processing on the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic structural diagram of a wafer bonding device provided by an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the structure of a wafer bonding device provided by an embodiment of the present invention in a state of practical application;

[0030] Figure 3 A schematic diagram of the structure of the wafer bonding device provided by an embodiment of the present invention in another state in practical application;

[0031] Figure 4 It is a schematic structural diagram of an elastic plate in another embodiment of the present invention;

[0032] Figure 5 It is a schematic structural diagram of an elastic plate in another embodiment of the present invention;

[0033] Figure 6 A flowchart of a wafer bonding method provided by an embodiment of the present invention.

[0034] Icons: 100-wafer bonding device; 110-elastic plate; 111-convex arc surface; 112-concave arc surface; 113-transition ring groove; 114-annular step; 120-support member; 130-gravity member; 140-lifting platform; 200-protective film; 210-gravity ring; 300-wafer. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] In the description of the present invention, it should be understood that the terms "upper", "lower", "inside", "outside", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use, or are directions or positional relationships commonly understood by those skilled in the art. These directions or positional relationships are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0039] Furthermore, the terms “first”, “second”, etc. are merely used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0040] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms such as "setting" and "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings.

[0042] Embodiment 1

[0043] See also Figure 1 , Figure 1 FIG. 1 is a schematic structural diagram of a wafer bonding device 100 provided in this embodiment.

[0044] The wafer bonding device 100 provided in this embodiment is used to adhere the protective film 200 to the wafer 300, and the wafer 300 is placed on the top of the protective film 200. The wafer bonding device 100 includes an elastic plate 110, a support member 120, a gravity member 130 and a lifting platform 140. The support member 120 is connected to the elastic plate 110. The elastic plate 110 is arc-shaped in the initial state and has a convex arc surface 111 and a concave arc surface 112. The gravity member 130 is connected to the support member 120, and the lifting platform 140 supports the gravity member 130 and is used to drive the gravity member 130 to move up and down in the vertical direction.

[0045] It can be understood that the elastic plate 110 has a certain elastic deformation ability, the connection point between the support member 120 and the elastic plate 110 is the center point, the center point refers to the geometric center, the support member 120 supports the elastic plate 110, and when the protective film 200 needs to be adhered to the wafer 300, the support member 120 applies a force to the elastic plate 110 so that the elastic plate 110 is deformed and the protective film 200 is adhered to the wafer 300. The elastic plate 110 is shown in the initial state. Figure 1 The arc-shaped plate structure shown in the figure has an upper surface which is a convex arc surface 111 and a lower surface which is connected to the support member 120 which is a concave arc surface 112 .

[0046] Please refer to Figure 2 , Figure 2 FIG. 1 is a schematic diagram of the structure of the wafer bonding device 100 in a state of actual application.

[0047] The convex curved surface 111 of the elastic plate 110 is used to carry the protective film 200. In fact, the protective film 200 has an adhesive surface and a non-adhesive surface. The convex curved surface 111 is used to carry the protective film 200. The non-adhesive surface of the protective film 200 contacts the convex curved surface 111, and the adhesive surface of the protective film 200 is away from the convex curved surface 111 to adhere to the wafer 300. The protective film 200 can be selected according to the actual application scenario. This application defines the model of the protective film 200. In this embodiment, the protective film 200 is preferably a blue film.

[0048] In this embodiment, the size of the protective film 200 is consistent with the size of the wafer 300. Figure 2 In the state shown, the center point of the elastic plate 110 is aligned with the center point of the protective film 200, and the edge of the protective film 200 sags due to gravity, thereby achieving the bonding of the non-adhesive surface and the convex arc surface 111. In this state, the wafer 300 is placed on the adhesive surface of the protective film 200 in a state of center point alignment, that is, the protective film 200 adheres to the center position of the wafer 300, that is, the protective film 200 located at the center point is in point contact with the center position of the wafer 300, and the elastic plate 110 is in point contact with the protective film 200 located at the center point. This embodiment does not limit the area of ​​point contact. It should be understood that the wafer 300 described here is placed on the adhesive surface of the protective film 200 in a state of center point alignment, that is, the center position of the wafer 300 is aligned with the center point of the elastic plate 110 and the center point of the protective film 200.

[0049] It should be understood that when the size of the protective film 200 is large enough, the present application does not limit whether the center point of the elastic plate 110 is aligned with the center point of the protective film 200, but only needs to ensure that the wafer 300 can be completely adhered by the protective film 200 in the end. For example, when the size of the protective film 200 is large enough, the wafer 300 can still be completely attached to the protective film 200 even if there is a deviation between the center point of the protective film 200 and the center point of the elastic plate 110, then the center point of the elastic plate 110 may not be aligned with the center point of the protective film 200; when the size of the elastic plate 110 is consistent with the size of the protective film 200, it is necessary to align the center point of the elastic plate 110, the center point of the protective film 200 and the center position of the wafer 300.

[0050] Please refer to Figure 3 , Figure 3 FIG. 1 is a schematic diagram of the structure of the wafer bonding device 100 in a state of actual application.

[0051] When the elastic plate 110 is under stress, the elastic plate 110 separates from the protective film 200 radially from the center point until the protective film 200 is completely attached to the wafer 300. It should be noted that the elastic plate 110 under stress refers to the state of the elastic plate 110 when the elastic plate 110 is subjected to a force in the opposite direction of the convex arc surface 111.

[0052] After the protective film 200 is set on the convex arc surface 111 and the wafer 300 is placed on the protective film 200, a downward pulling force is applied to the support member 120 through the combined structure of the gravity member 130 and the lifting platform 140, so that the elastic plate 110 is gradually separated from the protective film 200 along the radial direction from the center point, that is, the supporting part of the elastic plate 110 for the wafer 300 is radially diffused from the center point toward the periphery, driving the adhesion area of ​​the protective film 200 and the wafer 300 to diffuse radially from the center point to the periphery.

[0053] It should be understood that because the adhesive surface of the protective film 200 adheres to the wafer 300, a bonding force is generated between the protective film 200 and the wafer 300; on the contrary, because the non-adhesive surface of the protective film 200 contacts the convex arc surface 111, no bonding force is generated between the protective film 200 and the convex arc surface 111. When the elastic plate 110 is deformed by the downward force, the supporting part of the elastic plate 110 on the wafer 300 also changes accordingly, and due to the bonding force between the protective film 200 and the wafer 300, the protective film 200 and the convex arc surface 111 will separate, and the protective film 200 will naturally adhere to the wafer 300.

[0054] It is understandable that in Figure 2 In the state shown, the center point of the elastic plate 110, the center point of the protective film 200 and the center point of the wafer 300 are aligned, and the center position of the wafer 300 is adhered to the protective film 200 under the support of the support member 120. When the support member 120 is subjected to a downward pull force, the elastic plate 110 is pulled by the support member 120 to deform, and the center point of the elastic plate 110 and the center point of the protective film 200 are quickly separated, and a cavity is gradually formed at the center points of the two, as shown in FIG. Figure 3 shown.

[0055] The elastic plate 110 supports the protective film 200 at the peripheral position of the cavity, that is, it provides supporting force for the protective film 200 to adhere the corresponding part of the protective film 200 to the wafer 300. As the support member 120 is pulled down, the size of the cavity between the elastic plate 110 and the protective film 200 expands radially, and then the supporting part of the elastic plate 110 on the wafer 300 diffuses radially from the center point toward the periphery, thereby driving the adhesion area of ​​the protective film 200 and the wafer 300 to diffuse radially from the center point toward the periphery.

[0056] In other words, under the pull-down action of the support member 120, the elastic plate 110 deforms radially from the center point to the periphery, so that the elastic plate 110 gradually separates from the protective film 200; the contact point between the convex arc surface 111 and the protective film 200 forms a supporting force on the protective film 200 and the wafer 300. At the same time, due to the self-gravity of the wafer 300, the wafer 300 gradually falls during the bonding process with the protective film 200. The protective film 200 gradually bonds with the wafer 300 radially from the center point with the support force at the contact point, thereby completing the bonding. It should be understood that the number of contact points described in this embodiment can be multiple, and the multiple contact points can be continuous.

[0057] When the chip is mounted, the convex surface 111 of the elastic plate 110 is completely separated from the protective film 200 adhered to the wafer 300, and the bending state of the elastic plate 110 is the same as that of the protective film 200 adhered to the wafer 300. Figure 2 The initial state shown is opposite, which is equivalent to the convex arc surface 111 being transformed into a concave arc shape facing upward, and the concave arc surface 112 being transformed into a convex arc shape facing downward. The elastic plate 110 has elastic deformation ability and can be restored to its original shape before the next patch. Figure 2 The initial state shown can be reused.

[0058] It can be seen that the wafer bonding device 100 provided in this embodiment can make the wafer 300 and the protective film 200 gradually and evenly bond from the center point radially to the periphery, avoiding the generation of bubbles between the wafer 300 and the protective film 200. And the wafer bonding device 100 provided in this embodiment is made of deformable material, so that the wafer bonding device 100 can be reused. In addition, during the bonding process of the wafer 300 based on the wafer bonding device 100 provided in this embodiment, the P surface of the wafer 300 is always facing upwards and does not come into contact with any object, thereby avoiding the P surface of the wafer 300 from being contaminated.

[0059] The wafer bonding device 100 provided in this embodiment also includes a gravity ring 210. After the protective film 200 is set on the elastic plate 110, the gravity ring 210 is set on the periphery of the protective film 200. Due to the gravity of the gravity ring 210, the protective film 200 and the convex arc surface 111 of the elastic plate 110 are evenly and tightly fitted, and the gravity ring 210 is outside the periphery of the elastic plate 110, so that the protective film 200 is always kept in a taut state, avoiding the poor adhesion between the wafer 300 and the protective film 200 caused by the wrinkles of the protective film 200, thereby obtaining a better bonding effect. Preferably, the elongation of the protective film 200 is between 200% and 250%.

[0060] In this embodiment, the gravity ring 210 and the wafer 300 are both circular; the inner diameter of the gravity ring 210 is larger than the diameter of the wafer 300. It should be understood that the present application does not limit the shapes of the gravity ring 210 and the wafer 300, and it is only necessary to ensure that the area defined by the gravity ring 210 can completely accommodate the wafer 300.

[0061] In practical applications, the wafer bonding device 100 can be equipped with a lifting device, and the gravity ring 210 is hung on the lifting device. After the protective film 200 is placed on the convex arc surface 111 of the elastic plate 110, the gravity ring 210 is lowered by the lifting device so that the gravity ring 210 is fixed to the periphery of the protective film 200. During the lowering process of the gravity ring 210, the gravity ring 210 always remains in a horizontal state, and its center is always vertically aligned with the center point of the elastic plate 110. When the gravity ring 210 is lowered to abut against the periphery of the protective film 200, the lifting device is controlled to stop so that the protective film 200 remains taut.

[0062] In order to improve the uniformity of the patch and obtain a more ideal patch effect, in this embodiment, in any vertical plane where the center point of the elastic plate 110 is located, the cross-sections of the convex arc surface 111 and the concave arc surface 112 are both arc-shaped; that is, the inner wall surface of the concave arc surface 112 is hemispherical; and the outer wall surface of the convex arc surface 111 is hemispherical.

[0063] Considering that the wafer 300 has a certain degree of warping, if the curvature of the convex arc surface 111 is too small, it cannot be ensured that the center of the wafer 300 first contacts the protective film 200. If the curvature of the convex arc surface 111 is too large, the wafer 300 is prone to tilt after being placed on the protective film 200. Therefore, as a preferred embodiment, the radius R of the sphere where the convex arc surface 111 is located is 600 mm.

[0064] Furthermore, in order to ensure that the contact points between the elastic plate 110 and the protective film 200 (i.e., the supporting points of the elastic plate 110 on the wafer 300) can be uniformly diffused radially toward the periphery under the downward pull of the support member 120, thereby ensuring that the parts at the same radial position on the wafer 300 are uniformly adhered to the protective film 200 at the same time, in this embodiment, with the center point of the elastic plate 110 as the center of the circle, the thickness of the elastic plate 110 gradually increases radially. In this embodiment, the radius r of the sphere where the concave arc surface 112 is located is 400 mm.

[0065] It is understandable that in order to apply a smaller force to deform the elastic plate 110, the deformation speed of each point of the elastic plate 110 is ensured to be consistent. In this embodiment, the centers of the concave arc surface 112 and the convex arc surface 111 do not coincide, the thickness of the elastic plate 110 at the center point is the smallest, and the thickness of the elastic plate 110 gradually increases in the radial direction. Therefore, when the center point is subjected to the downward pull force of the support member 120, the same radius area of ​​the elastic plate 110 is subjected to the same force, which can ensure that the support part of the convex arc surface 111 on the protective film 200 is evenly diffused in a circular shape, thereby ensuring the uniformity and stability of the adhesion between the protective film 200 and the wafer 300.

[0066] Since the thickness at the center point of the elastic plate 110 is the smallest, in order to avoid rapid damage to the center point during repeated deformation of the elastic plate 110 and extend the service life, in this embodiment, the thickness of the elastic plate 110 at the center point is greater than 2 mm.

[0067] Preferably, in this embodiment, the elastic plate 110 and the support member 120 are integrally formed, and both are made of rubber. On the one hand, the rubber material has elastic deformation ability, which can make the elastic plate 110 deform under the pull-down action of the support member 120, thereby providing an upward force that diffuses radially from the center point to the periphery to the protective film 200. On the other hand, the support member 120 and the elastic plate 110 are integrally formed, which can make the joint point between the support member 120 and the elastic plate 110 firm and reliable, and can quickly transmit the pull-down force to the elastic plate 110, and the force transmission efficiency is high.

[0068] It is understandable that when the support member 120 is pulled down to deform the elastic plate 110, the supporting part of the elastic plate 110 on the protective film 200 needs to be always on the same circumference to avoid bubbles between the protective film 200 and the wafer 300 due to uneven supporting force of the elastic plate 110 on various parts of the protective film 200 after being pulled off. Therefore, in this embodiment, the combined structure of the gravity member 130 and the lifting platform 140 is used to apply force to the support member 120.

[0069] Specifically, the support member 120 is rod-shaped and extends in the vertical direction. The top end of the support member 120 is connected to the center point of the elastic plate 110, and the bottom end of the support member 120 is connected to the gravity member 130. The lifting platform 140 is actually a combination of a driving member and a support platform. The support platform is horizontally arranged and connected to the driving member and arranged on the top of the driving member. The support platform moves up and down in the vertical direction under the drive of the driving member; the driving member can be an oil cylinder, an air cylinder or a motor, etc. The gravity member 130 is placed on the support platform. During the vertical movement of the driving member, the supporting platform and the gravity member 130 arranged on the supporting platform are driven to move stably up and down in the vertical direction, and the force can be adjusted according to the actual application scenario.

[0070] Furthermore, in another embodiment, the structure of the elastic plate 110 may be adjusted to further improve the uniformity of the patch. Figure 4 , Figure 4 FIG. 1 is a schematic structural diagram of an elastic plate 110 in another embodiment.

[0071] In this embodiment, the concave arc surface 112 of the elastic plate 110 is concavely provided with a plurality of transition annular grooves 113, the radii of the circles where the plurality of transition annular grooves 113 are located are different from each other, and the centers of the plurality of transition annular grooves 113 coincide with the center point of the elastic plate 110. The plurality of transition annular grooves 113 play a role in positioning the deformation of the elastic plate 110 in stages, which is equivalent to correcting the problem of uneven deformation of the elastic plate 110 in stages, thereby ensuring the uniformity of adhesion between the protective film 200 and the wafer 300, and avoiding the occurrence of bubbles between the protective film 200 and the wafer 300 due to the uneven deformation of the elastic plate 110.

[0072] Specifically, in the process of the elastic plate 110 being deformed by the downward pulling force, the part that first reaches the transition annular groove 113 on the contact boundary composed of countless contact points arranged continuously in the circumferential direction briefly stops further separation from the protective film 200 in the buffer space provided by the transition annular groove 113. After all the contact boundaries reach the transition annular groove 113 and the buffer space of the transition annular groove 113 is fully utilized by the deformation of the elastic plate 110, that is, after the two groove side walls of the transition annular groove 113 are fully abutted, the contact boundary of the elastic plate 110 then diffuses radially uniformly with the transition annular groove 113 as the starting point, thereby ensuring the uniformity of the patch.

[0073] See also Figure 5 , Figure 5 FIG. 1 is a schematic structural diagram of an elastic plate 110 in yet another embodiment.

[0074] In this embodiment, the concave arc surface 112 of the elastic plate 110 has a plurality of annular steps 114, the radii of the circles where the plurality of annular steps 114 are located are different from each other, the centers of the circles where the plurality of annular steps 114 are located coincide with the center point of the elastic plate 110, and any annular step 114 is formed by increasing the radial thickness of the elastic plate 110.

[0075] Similarly, the multiple annular steps 114 play a role in positioning the deformation of the elastic plate 110 in stages, which is equivalent to correcting the possible uneven deformation in stages. Figure 4 The illustrated elastic plate 110 differs in that it achieves the positioning of the contact boundary by a uniform change in the diffusion resistance.

[0076] Specifically, when the elastic plate 110 is deformed by the downward pull force, the resistance of the portion of the contact boundary that first reaches the annular step 114 suddenly increases, hindering the further separation of the portion from the protective film 200. After all the contact boundaries reach the annular step 114, the downward pull force is evenly distributed to the contact boundaries, so that the contact boundaries of the elastic plate 110 are evenly diffused radially starting from the annular step 114, that is, radial synchronous diffusion.

[0077] In summary, the wafer bonding device 100 provided in this embodiment can ensure bonding uniformity, avoid the generation of bubbles, ensure that all parts of the protective film 200 are subjected to uniform force, and achieve better bonding processing for the wafer 300.

[0078] Embodiment 2

[0079] See also Figure 6 , Figure 6 The figure shows a flowchart of the wafer bonding method provided in this embodiment.

[0080] This embodiment further provides a wafer bonding method, which is applied to the aforementioned wafer bonding device 100. The wafer bonding method includes:

[0081] In step S101 , the protection film 200 is placed on the convex arc surface 111 of the elastic plate 110 .

[0082] It can be understood that the non-adhesive surface of the protective film 200 is actually placed on the convex arc surface 111 of the elastic plate 110, the center point of the protective film 200 is aligned with the center point of the elastic plate 110, and the edge of the protective film 200 droops due to gravity to achieve adhesion with the convex arc surface 111.

[0083] In step S102 , the wafer 300 is placed on the protective film 200 , and the center position of the wafer 300 is adhered to the protective film 200 at the center point, and the center point is the connection point between the support member 120 and the elastic plate 110 .

[0084] The center point of the wafer 300 is adhered to the center point of the adhesion surface of the protection film 200 , and is supported by the support member 120 .

[0085] In step S103 , a force is applied to the support member 120 so that the force drives the convex arc surface 111 to separate from the protection film 200 radially from the center point, so that the adhesion area between the protection film 200 and the wafer 300 spreads radially from the center point to the periphery.

[0086] As the support member 120 is pulled down, the elastic plate 110 is gradually separated from the protective film 200 from the center point, and the separation boundary between the convex arc surface 111 and the protective film 200 forms an upward force on the protective film 200. Combined with the self-gravity of the wafer 300, the wafer 300 gradually falls during the bonding process, and the protective film 200 gradually bonds and adheres to the wafer 300 from the center point to the periphery with the force provided by the separation boundary.

[0087] In fact, in the process of laminating the protective film 200 from the center point to the periphery, the force between the protective film 200 and the wafer 300 on different radii is preferably consistent, so that the wafer 300 can be evenly laminated at each radial position from the center point to the periphery. Therefore, in this embodiment, a gradually decreasing downward pulling force is applied to the support member 120, so that the diffusion speed of the adhesion area of ​​the protective film 200 and the wafer 300 in the radial direction is gradually reduced.

[0088] Step S104 , when the wafer 300 is completely adhered by the protective film 200 , stop applying force to the support member 120 .

[0089] When the wafer 300 is completely adhered to the protective film 200, the bending state of the elastic plate 110 is the same as that of the wafer 300. Figure 2 The initial state shown is opposite, which is equivalent to the convex arc surface 111 being transformed into an upward concave arc shape, and the concave arc surface 112 being transformed into a downward convex arc shape.

[0090] In fact, in this embodiment, after the step of placing the protective film 200 on the convex arc surface 111 of the elastic plate 110, the wafer bonding method further includes the following steps:

[0091] A gravity ring 210 is disposed on the periphery of the protection film 200 to fix the protection film 200 to the convex arc surface 111 .

[0092] The radius of the protection film 200 disposed on the convex arc surface 111 is greater than the radius of the wafer 300 .

[0093] In fact, as a preference, the present embodiment provides a protective film 200 with an elongation between 200% and 250%. If the elongation of the protective film 200 is too small, it will not be able to fully fit with the convex curved surface 111 under the action of gravity.

[0094] Preferably, the gravity ring 210 in this embodiment is an iron ring. Due to its gravity, the protective film 200 and the convex arc surface 111 of the elastic plate 110 are evenly and tightly fitted, and the gravity ring 210 is outside the periphery of the elastic plate 110, so that the protective film 200 always remains taut, thereby obtaining a better patch effect.

[0095] In summary, benefiting from the beneficial effects of the wafer bonding device 100, the wafer bonding method provided in this embodiment has the characteristic of better bonding effect.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wafer bonding device, characterized in that: Used for adhering a protective film (200) to a wafer (300); the wafer bonding device (100) comprises an elastic plate (110) and a support member (120), the support member (120) being connected to the elastic plate (110), and the connection point between the support member (120) and the elastic plate (110) being a center point; When the elastic plate (110) is in an initial state, the convex arc surface (111) of the elastic plate (110) carries the protective film (200), and the protective film (200) located at the center point adheres to the center position of the wafer (300); When the elastic plate (110) is under stress, the elastic plate (110) is separated from the protective film (200) radially from the center point until the protective film (200) is completely attached to the wafer (300).

2. The wafer bonding device according to claim 1, characterized in that: The material of the elastic plate (110) includes rubber, and / or, The elastic plate (110) and the support member (120) are integrally formed.

3. The wafer bonding device according to claim 1, characterized in that: When the elastic plate (110) is in an initial state, the elastic plate (110) comprises a concave arc surface (112); in any vertical plane where the center point is located, the cross-sections of the convex arc surface (111) and the concave arc surface (112) are both in the shape of circular arcs.

4. The wafer bonding device according to any one of claims 1 to 3, characterized in that: With the central point as the center of the circle, the thickness of the elastic plate (110) gradually increases in the radial direction.

5. The wafer bonding device according to any one of claims 1 to 3, characterized in that: When the elastic plate (110) is in an initial state, the elastic plate (110) comprises a concave arc surface (112); the concave arc surface (112) is provided with a plurality of transition annular grooves (113); the radii of the circles where the plurality of transition annular grooves (113) are located are different from each other; and the centers of the circles where the plurality of transition annular grooves (113) are located all coincide with the center point.

6. The wafer bonding device according to any one of claims 1 to 3, characterized in that: When the elastic plate (110) is in an initial state, the elastic plate (110) comprises a concave arc surface (112); the concave arc surface (112) has a plurality of annular steps (114); the radii of the circles where the plurality of annular steps (114) are located are different from each other; the centers of the circles where the plurality of annular steps (114) are located all coincide with the center point; and any one of the annular steps (114) is formed by the increase in the radial thickness of the elastic plate (110).

7. The wafer bonding device according to claim 1, characterized in that: The wafer bonding device (100) further comprises a gravity member (130) and a lifting platform (140), wherein the gravity member (130) is connected to the support member (120), and the lifting platform (140) supports the gravity member (130) and is used to drive the support member (120) to move up and down in a vertical direction.

8. The wafer bonding device according to claim 1, characterized in that: The wafer bonding device (100) further comprises a gravity ring (210), wherein the gravity ring (210) is arranged on the periphery of the protective film (200) located on the elastic plate (110).

9. A wafer bonding method, applied to the wafer bonding device (100) according to any one of claims 1 to 8, characterized in that: The wafer bonding method comprises: Placing a protective film (200) on the convex curved surface (111) of the elastic plate (110); Placing a wafer (300) on the protective film (200), wherein the center position of the wafer (300) adheres to the protective film (200) at a center point, and the center point is a connection point between the support member (120) and the elastic plate (110); Applying a force to the support member (120) so that the force drives the convex arc surface (111) to separate from the protective film (200) radially from the center point, so that the adhesion area between the protective film (200) and the wafer (300) spreads radially from the center point to the periphery; When the wafer (300) is completely adhered to the protective film (200), the application of force to the support member (120) is stopped.

10. The wafer bonding method according to claim 9, characterized in that: After placing the protective film (200) on the convex curved surface (111) of the elastic plate (110), the wafer bonding method further comprises: A gravity ring (210) is provided on the periphery of the protective film (200) to fix the protective film (200) to the convex curved surface (111); Wherein, the radius of the protective film (200) disposed on the convex curved surface (111) is greater than the radius of the wafer (300).

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