Laser debonding device

Abstract

The utility model relates to a laser debonding device, and belongs to the technical field of semiconductor laser manufacturing. The device comprises a workbench which is provided with a first supporting piece and a second supporting piece; the rotary carrying table assembly is mounted on the workbench and is used for fixing a bonding wafer; the de-bonding laser device is mounted on the first supporting piece and is positioned right above the rotary carrying table assembly; the degumming laser device is installed on the second supporting piece and provided with a laser optical module, and the optical axis of the laser optical module is perpendicular to the side face of the bonding wafer; the blowing device is installed on the second supporting piece and provided with a blowing pipe, and the axis of the outlet end of the blowing pipe is coaxial with the optical axis of the laser optical module. The glue removing laser device is controlled to process the edge excessive glue on the side face of the bonding wafer, then the bonding laser device is controlled to remove the bonding glue on the middle layer of the bonding wafer, meanwhile, the blowing device is used for assisting wafer separation and dust removal, operation is easy, the production efficiency of the wafer can be improved, and the fragment risk is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor laser manufacturing, in particular to a laser debonding device. Background Art

[0002] Wafer laser debonding is to focus a laser beam on the bonding layer between the wafer and the carrier wafer and scan the bonding layer. When the laser irradiates the bonding glue, it will decompose, turning the bonding glue into powder and losing its viscosity. After scanning the entire bonding layer, the laser heating is stopped, and a transfer device with a chuck is used to separate the wafer and the carrier wafer. However, there are the following problems in the current process method:

[0003] (1) During wafer bonding, it is difficult to avoid the phenomenon of glue overflow at the edge. The overflowing glue will stick to the edge side part of the wafer pair, making it impossible to completely debond the side edge part during laser debonding perpendicular to the wafer surface, which is likely to cause the risk of separation and fragmentation, and the yield cannot be guaranteed;

[0004] (2) After the bonding glue is irradiated by the laser, it will turn into dust particles. If not processed in time, the dust will densely adhere to the residual glue on the carrier and the wafer, affecting the cleaning of the wafer after separation. Summary of the Utility Model

[0005] Based on this, in view of the problem that during wafer bonding, it is difficult to avoid the phenomenon of glue overflow at the edge. The overflowing glue will stick to the edge side part of the wafer pair, making it impossible to completely debond the side edge part during laser debonding perpendicular to the wafer surface, which is likely to cause the risk of separation and fragmentation, and the yield cannot be guaranteed, and after the bonding glue is irradiated by the laser, it will turn into dust particles. If not processed in time, the dust will densely adhere to the residual glue on the carrier and the wafer, affecting the cleaning of the wafer after separation, it is necessary to provide a laser debonding device.

[0006] A laser debonding device provided by the utility model includes:

[0007] A workbench having a first support member and a second support member;

[0008] A rotating stage assembly installed on the workbench and used for fixing the bonded wafer;

[0009] A debonding laser device installed on the first support member and located directly above the rotating stage assembly;

[0010] A degumming laser device installed on the second support member and having a laser optical module, the optical axis of the laser optical module being perpendicular to the side surface of the bonded wafer;

[0011] A blowing device installed on the second support member and having a blowing pipe, the axis of the outlet end of the blowing pipe being coaxial with the optical axis of the laser optical module.

[0012] In one embodiment, the rotating stage assembly includes a first motor and a suction stage. The first motor is mounted on the workbench, and the suction stage is fixed to the output end of the first motor.

[0013] In one embodiment, the axis of the outlet end of the blow pipe and the optical axis of the laser optical module both coincide with the transverse axis of the bonding adhesive layer of the bonding wafer.

[0014] In one embodiment, the wavelengths of the laser beam emitted by the debonding laser device and the laser beam emitted by the laser optical module are such that the bonding adhesive has the strongest absorption rate for them. The focus of the laser beam emitted by the debonding laser device is in the middle of the bonding adhesive layer, and the focal depth of the laser beam emitted by the debonding laser device is greater than half of the thickness of the bonding adhesive layer.

[0015] In one embodiment, the energy density of the light spot at the focus of the laser beam emitted by the laser optical module is greater than the decomposition threshold of the bonding adhesive. The center of the light spot of the laser beam emitted by the laser optical module is at the joint on the side of the bonding wafer, and the size of the focused laser spot of the laser beam emitted by the laser optical module is greater than the thickness of the bonding wafer.

[0016] In one embodiment, the scanning range of the debonding laser device is greater than the area of the bonding wafer. The light spot at the focus of the laser beam emitted by the debonding laser device remains uniform within the scanning range, and the focal length of the light spot at the focus of the laser beam emitted by the debonding laser device is on the lower surface of the bonding adhesive layer.

[0017] In one embodiment, a groove is formed on the surface of the second support member. A third support member is slidably connected in the groove. A fourth support member is arranged on the surface of the third support member. The debonding laser device and the blowing device are both mounted on the fourth support member. A second motor is mounted on the side wall of the second support member. A first gear is fixedly connected to the output end of the second motor. A first rack is fixedly connected to the surface of the third support member. The first rack meshes with the first gear.

[0018] In one embodiment, a rotating rod is fixedly connected to the surface of the fourth support member. The rotating rod is rotatably connected to the third support member. A third motor is mounted on the surface of the third support member. A second gear is fixedly connected to the output end of the third motor. A third gear is fixedly connected to the outer wall of the rotating rod. The third gear meshes with the second gear.

[0019] The above laser debonding device fixes the bonded wafer on the adsorption stage, controls the degumming laser device to process the edge overflow glue on the side of the bonded wafer, then controls the debonding laser device to release the bonding glue in the middle layer of the bonded wafer, and at the same time uses the blowing device to assist in wafer separation and dust removal. The operation is simple and convenient to use, which is beneficial to improving the production efficiency of wafers and reducing the risk of fragmentation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 Schematic structural diagram of the laser debonding device in an embodiment;

[0022] Figure 2 Schematic partial structural diagram of the laser debonding device in an embodiment;

[0023] Figure 3 Schematic height adjustment structural diagram of the laser debonding device in an embodiment;

[0024] Figure 4 Schematic angle adjustment structural diagram of the laser debonding device in an embodiment.

[0025] Reference numerals:

[0026] 200, workbench; 210, first support member; 220, second support member; 221, groove; 300, rotating stage assembly; 310, first motor; 320, adsorption stage; 400, debonding laser device; 500, degumming laser device; 510, laser optical module; 600, blowing device; 610, blow pipe; 700, third support member; 710, second motor; 720, first gear; 730, first rack; 740, fourth support member; 750, rotating rod; 760, third motor; 770, second gear; 780, third gear. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts shall fall within the protection scope of the present utility model.

[0028] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the description of the present utility model are only for the purpose of illustration and do not represent the only implementation manner.

[0029] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0030] In the present utility model, unless otherwise clearly defined and limited, the first feature may be in direct contact with the second feature "on" or "under" the second feature, or the first feature and the second feature may be in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or only indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or only indicates that the first feature has a lower horizontal height than the second feature.

[0031] Unless otherwise defined, all technical and scientific terms used in the description of the present utility model have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present utility model belongs. The terms used in the description of the present utility model are only for the purpose of describing specific implementation manners and are not intended to limit the present utility model. The term "and / or" used in the description of the present utility model includes any and all combinations of one or more of the related listed items.

[0032] Wafer laser debonding is to focus the laser beam on the bonding layer between the wafer and the carrier wafer and scan the bonding layer. When the laser irradiates the bonding adhesive, it will decompose, turning the bonding adhesive into powder and losing its viscosity. After scanning the entire bonding layer, the laser heating is stopped, and a transfer device with a chuck is used to separate the wafer and the carrier wafer. However, there are several problems with this process method at present:

[0033] 1. When bonding wafers, it is difficult to avoid the phenomenon of glue overflow at the edge. The overflowing glue will stick to the edge side part of the wafer pair. When performing laser debonding perpendicular to the wafer surface, the side edge part cannot be completely debonded, which is likely to cause the risk of separation and fragmentation, and the yield cannot be guaranteed;

[0034] 2. After the laser beam scans the bonding area of the wafer pair, there is still a bonding force between a small number of wafer pieces and the carrier wafer, resulting in incomplete debonding. When the carrier wafer and the wafer are separated subsequently, it may cause mechanical damage to the wafer, and even fragmentation in severe cases;

[0035] 3. After the bonding adhesive is irradiated by the laser, it will become dust particles. If the dust is not removed in time, the dust will adhere densely to the residual glue on the carrier and the wafer, affecting the cleaning of the separated wafer.

[0036] To solve the above problems, the following will be combined with Figures 1 - 4 Describe the laser debonding device of the present utility model.

[0037] As Figure 1 And Figure 2 Shown, in one embodiment, a laser debonding device includes a workbench 200, a rotating stage assembly 300, a debonding laser device 400, a glue-removing laser device 500, and a blowing device 600.

[0038] The workbench 200 has a first support member 210 and a second support member 220.

[0039] The rotating stage assembly 300 is installed on the workbench 200, and the rotating stage assembly 300 is used to fix the bonded wafers.

[0040] The debonding laser device 400 is installed on the first support member 210, and the debonding laser device 400 is located directly above the rotating stage assembly 300. The spot of the debonding laser device 400 is adjusted to a square flat-top spot of 300μm×300μm, and the scanning system is a three-dimensional dynamic scanning galvanometer.

[0041] The glue-removing laser device 500 is installed on the second support member 220, and the glue-removing laser device 500 has a laser optical module 510. The optical axis of the laser optical module 510 is perpendicular to the side of the bonded wafer.

[0042] The air blowing device 600 is installed on the second support member 220, and the air blowing device 600 has an air blowing pipe 610. The axis of the outlet end of the air blowing pipe 610 is coaxial with the optical axis of the laser optical module 510.

[0043] Specifically, the rotary stage assembly 300 includes a first motor 310 and an adsorption stage 320. The first motor 310 is installed on the workbench 200, and the adsorption stage 320 is fixed to the output end of the first motor 310. The first motor 310 is a motor whose speed can be adjusted. The adsorption stage 320 can rotate 360 degrees steplessly at different speeds under the control of the first motor 310.

[0044] It should be added that the axis of the outlet end of the air blowing pipe 610 and the optical axis of the laser optical module 510 both coincide with the lateral axis of the bonding adhesive layer of the bonded wafer.

[0045] In this laser debonding device, by placing the bonded wafer on the adsorption stage 320 and fixing it, controlling the degumming laser device 500 to process the edge overflow glue on the side of the bonded wafer, and then controlling the debonding laser device 400 to release the bonding glue in the middle layer of the bonded wafer, while using the air blowing device 600 to assist in wafer separation and dust removal, the operation is simple and convenient to use, which is beneficial to improving the production efficiency of the wafer and reducing the risk of fragmentation.

[0046] In this embodiment, the wavelengths of the laser beams emitted by the debonding laser device 400 and the laser optical module 510 are both such that the bonding glue has the strongest absorption rate for them. The focus of the laser beam emitted by the debonding laser device 400 is in the middle of the bonding glue layer, and the depth of focus of the laser beam emitted by the debonding laser device 400 is greater than half of the thickness of the bonding glue layer.

[0047] In this embodiment, the energy density of the light spot at the focus of the laser beam emitted by the laser optical module 510 is greater than the decomposition threshold of the bonding glue. The center of the light spot of the laser beam emitted by the laser optical module 510 is at the joint of the side of the bonded wafer, and the size of the focused laser spot of the laser beam emitted by the laser optical module 510 is greater than the thickness of the bonded wafer.

[0048] In this embodiment, the scanning range of the debonding laser device 400 is greater than the area of the bonded wafer. The light spot at the focus of the laser beam emitted by the debonding laser device 400 remains uniform within the scanning range, and the focal length of the light spot at the focus of the laser beam emitted by the debonding laser device 400 is on the lower surface of the bonding glue layer.

[0049] Such as Figure 3 and Figure 4As shown, in one embodiment, a groove 221 is formed on the surface of the second support member 220. A third support member 700 is slidably connected in the groove 221. A fourth support member 740 is disposed on the surface of the third support member 700. The debonding laser device 500 and the air blowing device 600 are both mounted on the fourth support member 740. A second motor 710 is mounted on the side wall of the second support member 220. The output end of the second motor 710 is fixedly connected to a first gear 720. A first rack 730 is fixedly connected to the surface of the third support member 700. The first rack 730 meshes with the first gear 720.

[0050] By starting the second motor 710 to drive the first gear 720 to rotate, the first gear 720 drives the first rack 730 to move, so as to conveniently adjust the positions of the air blowing pipe 610 and the laser optical module 510 as needed, so that the axes of the air blowing pipe 610 and the laser optical module 510 always coincide with the transverse axis of the bonding glue layer of the bonded wafer.

[0051] Specifically, a rotating rod 750 is fixedly connected to the surface of the fourth support member 740. The rotating rod 750 is rotatably connected to the third support member 700. A third motor 760 is mounted on the surface of the third support member 700. The output end of the third motor 760 is fixedly connected to a second gear 770. A third gear 780 is fixedly connected to the outer wall of the rotating rod 750. The third gear 780 meshes with the second gear 770.

[0052] By starting the third motor 760 to drive the second gear 770 to rotate, the second gear 770 drives the third gear 780 to rotate, the third gear 780 drives the rotating rod 750 to rotate, and the rotating rod 750 drives the fourth support member 740 to rotate, so as to conveniently adjust the angles of the air blowing pipe 610 and the laser optical module 510 as needed.

[0053] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0054] The above embodiments only represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A laser debonding device, characterized in that: include: A workbench having a first support member and a second support member; A rotating stage assembly is mounted on the workbench and is used to fix the bonded wafer; A debonding laser device is mounted on the first support member and is located directly above the rotating stage assembly; A glue removal laser device is mounted on the second support member and has a laser optical module, wherein the optical axis of the laser optical module is perpendicular to the side surface of the bonded wafer; The air blowing device is installed on the second supporting member and has an air blowing pipe, wherein the axis of the outlet end of the air blowing pipe is coaxial with the optical axis of the laser optical module.

2. The laser debonding device according to claim 1, characterized in that: The rotating platform assembly includes a first motor and an adsorption-type platform, wherein the first motor is mounted on a workbench, and the adsorption-type platform is fixed at an output end of the first motor.

3. The laser debonding device according to claim 2, characterized in that: The axis of the outlet end of the air blowing pipe and the optical axis of the laser optical module both coincide with the transverse axis of the bonding adhesive layer of the bonding wafer.

4. The laser debonding device according to claim 3, characterized in that: The wavelengths of the laser beam emitted by the debonding laser device and the laser beam emitted by the laser optical module are both those at which the bonding adhesive has the strongest absorption rate. The focus of the laser beam emitted by the debonding laser device is in the middle of the bonding adhesive layer, and the focal depth of the laser beam emitted by the debonding laser device is greater than half of the thickness of the bonding adhesive layer.

5. The laser debonding device according to claim 4, characterized in that: The energy density of the spot at the focus of the laser beam emitted by the laser optical module is greater than the decomposition threshold of the bonding glue, the center of the spot of the laser beam emitted by the laser optical module is at the bonding part of the side of the bonding wafer, and the size of the focused laser spot of the laser beam emitted by the laser optical module is greater than the thickness of the bonding wafer.

6. The laser debonding device according to claim 5, characterized in that: The scanning range of the debonding laser device is larger than the area of ​​the bonded wafer, the light spot at the focus of the laser beam emitted by the debonding laser device remains uniform within the scanning range, and the focal length of the light spot at the focus of the laser beam emitted by the debonding laser device is on the lower surface of the bonding adhesive layer.

7. The laser debonding device according to any one of claims 1 to 6, characterized in that: A groove is provided on the surface of the second support member, and a third support member is slidably connected in the groove. A fourth support member is arranged on the surface of the third support member, and the glue removal laser device and the air blowing device are both installed on the fourth support member. A second motor is installed on the side wall of the second support member, and a first gear is fixedly connected to the output end of the second motor. A first rack is fixedly connected to the surface of the third support member, and the first rack is meshed with the first gear.

8. The laser debonding device according to claim 7, characterized in that: A rotating rod is fixedly connected to the surface of the fourth support member, and the rotating rod is rotatably connected to the third support member. A third motor is installed on the surface of the third support member, and a second gear is fixedly connected to the output end of the third motor. A third gear is fixedly connected to the outer wall of the rotating rod, and the third gear is meshed with the second gear.

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