Crystal grain separation method, film expansion jig and separation platform

Abstract

The invention provides a crystal grain separation method, a film expansion jig and a separation platform. The method comprises the steps that a wafer is fixed to a separation platform through an expansion film, the wafer is provided with a plurality of to-be-separated crystal grains formed after cutting, and the wafer is placed on the first side of the expansion film; driving a first film expansion disc of a film expansion jig of the separation platform to jack up the expansion film in the first direction, so that the expansion film is subjected to first film expansion treatment to separate crystal grains on the expansion film; the first direction is a direction from a second side of the expansion film to the first side, and the second side is opposite to the first side; at least one second film expanding disc of the film expanding jig is driven to further jack up the expanding film relative to the first film expanding disc in the first direction, so that the expanding film is subjected to second film expanding treatment for at least one time; the second film expanding disc can rise relative to the first film expanding disc in the first direction. The method can separate crystal grains in a smaller area, and is wider in application range.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a grain separation method, a film expansion fixture and a separation platform. Background Art

[0002] In the packaging process, for wafers with narrow cutting lines, a dicing process is usually used to form multiple dies to be separated on the wafer; then the dies are separated by film expansion. However, it is difficult to separate multiple dies with smaller areas using existing separation methods. Summary of the invention

[0003] The grain separation method, film expansion fixture and separation platform provided in the present application can separate multiple grains to be separated with a smaller area.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a method for separating grains, the method comprising:

[0005] Fixing a wafer on a separation platform through an expansion film, wherein the wafer has a plurality of dies to be separated formed after cutting, and the wafer is placed on a first side of the expansion film;

[0006] Driving the first film expansion plate of the film expansion fixture of the separation platform to lift the expansion film along a first direction, so that the expansion film undergoes a first film expansion process to separate the grains on the expansion film; wherein the first direction is a direction from the second side of the expansion film to the first side, and the second side is relative to the first side;

[0007] Drive at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one second film expanding treatment; wherein the second film expanding plate can be lifted relative to the first film expanding plate along the first direction.

[0008] In one embodiment of the present application, the step of driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction includes:

[0009] According to the order in which the cross-sectional area of ​​at least one second film expanding plate of the film expanding fixture gradually decreases, the at least one second film expanding plate is driven in sequence to further lift the expanded film relative to the first film expanding plate along the first direction; wherein, the at least one second film expanding plate is coaxially arranged with the first film expanding plate; and the cross-sectional area of ​​each of the second film expanding plates is smaller than the cross-sectional area of ​​the first film expanding plate.

[0010] In one embodiment of the present application, the total lifting height of the second film expanding disk relative to the supporting platform of the separation platform along the first direction is negatively correlated with the cross-sectional area of ​​the second film expanding disk.

[0011] In one embodiment of the present application, each of the second film expansion plates includes a plurality of film expansion blocks along its circumferential direction, the plurality of film expansion blocks are independently arranged, and each of the film expansion blocks is configured to be independently raised or lowered;

[0012] After the step of driving at least one second film expanding plate of the film expanding jig to further lift the expanded film relative to the first film expanding plate along the first direction so that the expanded film undergoes at least one second film expanding treatment, the step further includes: driving the film expanding block at a preset position to further lift the expanded film relative to the second film expanding plate where the film expanding block is located along the first direction so that the expanded film undergoes at least one third film expanding treatment.

[0013] In one embodiment of the present application, after the step of driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction so that the expanded film undergoes at least one second film expanding process, the step further includes:

[0014] unlocking the wafer from the separation platform and re-fixing the wafer to another separation platform via the expansion film;

[0015] Drive at least one third film expanding plate of the film expanding fixture of the other separation platform to further lift the expanded film relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one third film expanding treatment; wherein, the at least one third film expanding plate is adjacent or spaced apart, and the central axes of every two third film expanding plates are spaced apart; the cross-sectional area of ​​each third film expanding plate is smaller than the cross-sectional area of ​​any second film expanding plate.

[0016] In one embodiment of the present application, the orthographic projection of the at least one third film expansion disk on the wafer is at least located at another position of the wafer different from the central position of the wafer.

[0017] In one embodiment of the present application, the step of driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction so that the expanded film undergoes at least one second film expanding process includes:

[0018] Drive at least one second film expanding plate of the film expanding fixture to simultaneously or sequentially lift up relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one second film expanding treatment; wherein, the at least one second film expanding plate is adjacent or spaced apart, and the central axes of every two second film expanding plates are spaced apart; and the cross-sectional area of ​​each second film expanding plate is smaller than the cross-sectional area of ​​the first film expanding plate.

[0019] In one embodiment of the present application, it also includes:

[0020] Acquire image information of the wafer, and determine region information of a to-be-separated region of the wafer based on the image information; wherein the grains in the to-be-separated region have not been completely separated; and the region information includes position information;

[0021] Based on the position information, the second film expansion disk at the corresponding position is driven to be lifted up relative to the first film expansion disk along the first direction to perform the second film expansion process.

[0022] In one embodiment of the present application, the region information further includes the degree of separation of the grains; and the method further includes:

[0023] Based on the separation degree of the crystal grains, the second film expansion disk at the corresponding position is driven to be lifted up to a preset height relative to the first film expansion disk along the first direction; wherein the separation degree of one crystal grain corresponds to one preset height.

[0024] In order to solve the above technical problems, another technical solution adopted by the present application is to provide a film expansion jig applied to a separation platform to separate the grains in the wafer fixed on the separation platform by the expansion film, and the film expansion jig includes:

[0025] a first film expansion plate, configured to be movable along a first direction to lift up the expansion film fixed on the separation platform so that the expansion film undergoes a first film expansion process, wherein the wafer is placed on a first side of the expansion film, the first direction is a direction from a second side of the expansion film to the first side, and the second side is relative to the first side;

[0026] At least one second film expansion plate is configured to be able to rise relative to the first film expansion plate along the first direction to further lift the expansion film.

[0027] In one embodiment of the present application, a cross-sectional area of ​​each of the second film expansion disks is smaller than a cross-sectional area of ​​the first film expansion disk.

[0028] In one embodiment of the present application, there are multiple second film expanding disks; the cross-sectional areas of the multiple second film expanding disks are different, and the multiple second film expanding disks are coaxially arranged with the first film expanding disk.

[0029] In one embodiment of the present application, the first film expanding disk is in a hollow ring shape; along a direction close to the central axis of the first film expanding disk, a plurality of the second film expanding disks are sequentially sleeved in the hollow area of ​​the first film expanding disk.

[0030] In one embodiment of the present application, among the plurality of second film expanding disks, one of the second film expanding disks that is closest to the central axis of the first film expanding disk is a solid disk; and the other second film expanding disks are all hollow ring-shaped.

[0031] In one embodiment of the present application, each of the second film expansion disks includes a plurality of film expansion blocks along its circumferential direction, the plurality of film expansion blocks are independently arranged, and each of the film expansion blocks is configured to be independently raised or lowered.

[0032] In one embodiment of the present application, the cross-sectional area of ​​the smallest second film expansion disk among the plurality of second film expansion disks is not greater than 9 mm 2 .

[0033] In one embodiment of the present application, there are multiple second film expanding disks, and the multiple second film expanding disks are arranged adjacent to or at intervals, and the central axes of every two second film expanding disks are arranged at intervals.

[0034] In one embodiment of the present application, the first film expansion disk has at least one through hole; the through hole penetrates the first side surface and the second side surface of the first film expansion disk;

[0035] There are multiple second film expansion plates, and the multiple second film expansion plates are arranged in the at least one through hole.

[0036] In one embodiment of the present application, the cross-sectional area of ​​the second film expansion disk is not greater than 9 mm 2 .

[0037] In one embodiment of the present application, the ratio of the sum of the cross-sectional areas of all the second film expansion disks to the cross-sectional area of ​​the first film expansion disk is 0.9-1.

[0038] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a separation platform, including the above-mentioned membrane expansion jig.

[0039] The beneficial effects of the embodiments of the present application are different from the prior art. The method for separating grains provided in the embodiments of the present application is to lift up the expansion film along the first direction by driving the first expansion disk of the expansion jig of the separation platform, so that the expansion film undergoes the first expansion treatment to separate the grains on the expansion film; and then further drive at least one second expansion disk of the expansion jig to further lift up the expansion film along the first direction, so that the expansion film undergoes at least one second expansion treatment. This not only increases the lifting height of the expansion film, and increases the number of times the wafer expansion treatment is performed, but can also effectively increase the expansion of the central part of the wafer, thereby more effectively separating the grains; and each expansion treatment can increase the spacing between the separated grains, giving the unseparated grains to be separated more expansion space, so that the method can separate multiple grains to be separated with a smaller area, and has a wider range of applications. At the same time, the method is compatible with the situation where a single expansion cannot completely separate the grains to be separated after the wafer has been invisible cut. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0041] Figure 1 A schematic diagram of the structure of a film expansion fixture provided in one embodiment of the present application;

[0042] Figure 2 A schematic diagram of the structure of the first film expansion plate and the expansion film when they are attached to each other according to an embodiment of the present application;

[0043] Figure 3 A schematic diagram of a structure in which a first film expansion plate lifts up an expansion film along a first direction provided in an embodiment of the present application;

[0044] Figure 4 for Figure 3 A schematic diagram of the structure in which the expansion membrane in the structure shown is lifted up by a second expansion membrane disk;

[0045] Figure 5 for Figure 4 A schematic diagram of the structure in which the expansion membrane is lifted up by another second expansion membrane disk;

[0046] Figure 6 A schematic diagram of the structure of a second film expansion disk provided in one embodiment of the present application;

[0047] Figure 7 A schematic structural diagram of a first film expansion disk provided in another embodiment of the present application;

[0048] Figure 8A schematic diagram of the structure of a film expansion fixture provided in another embodiment of the present application;

[0049] Fig. 9 A schematic diagram of the structure of a wafer after a first film expansion process provided by another embodiment of the present application;

[0050] Fig.10 To use Figure 8 A second film expansion plate in the film expansion fixture is Fig. 9 A schematic diagram of the process of performing the second film expansion treatment on the structure shown;

[0051] Fig.11 A flow chart of a method for separating grains provided in one embodiment of the present application;

[0052] Fig.12 A schematic diagram of the structure of a wafer provided in one embodiment of the present application.

[0053] Description of Reference Numerals

[0054] 10-film expansion jig; 1-first film expansion plate; 11-through hole; 2-second film expansion plate; 2a-film expansion block;

[0055] 20-wafer; 21-crystal grain; 22-substrate; 23-dielectric layer; 24-metal structure;

[0056] 30-expanded membrane;

[0057] Y - first direction. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0059] The terms "first", "second", "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", "third" can expressly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the embodiments of this application, all directional indications (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the steps or units listed, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0060] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0061] In the related technology, for narrow cutting products, the invisible cutting process is usually used to form cracks inside the wafer; then the wafer is separated into multiple grains by film expansion. However, for small-sized wafers, for example, wafers with a size less than 3*3mm, it is difficult to separate multiple grains by one film expansion because the distance that a single grain can be pulled apart is not enough. Therefore, invisible cutting is currently usually used on large-sized wafers.

[0062] In view of this, an embodiment of the present application provides a new method for separating grains, which can also separate multiple grains to be separated on a small-sized wafer and is applicable to a wide range of applications.

[0063] In order to facilitate the description and understanding of the entire implementation process of the grain separation method, the product structure involved in this application is first introduced below.

[0064] The present application is described in detail below with reference to the accompanying drawings and embodiments.

[0065] See also Figure 1 to Figure 2 , Figure 1 A schematic diagram of the structure of a film expansion fixture 10 provided in one embodiment of the present application; Figure 2A schematic diagram of the structure of the first film expansion disk 1 provided in one embodiment of the present application when the expansion film 30 is attached. In this embodiment, a separation platform is provided, which includes a carrier and a fixing component arranged on the carrier, a film expansion fixture 10 and a driving component. The fixing component is configured to fix the expansion film 30; the expansion film 30 has a first side and a second side opposite to each other, a wafer 20 is arranged on the first side of the expansion film 30, and the second side of the expansion film 30 is configured to face the separation platform so as to perform film expansion processing on the wafer 20. The wafer 20 has a plurality of grains 21 to be separated formed after cutting.

[0066] In some embodiments, the wafer 20 has a plurality of dies 21 to be separated after being cut, and the “cutting” involved includes complete cutting and incomplete cutting. Complete cutting means that after the wafer 20 is cut, the plurality of dies 21 are completely cut; incomplete cutting means that after the wafer 20 is cut, the plurality of dies 21 are not completely cut.

[0067] In one embodiment, the fixing assembly may include a clamping member, which is fixedly connected to the carrier, and the clamping member is configured to clamp and fix the expansion membrane 30 from the circumferential edge of the expansion membrane 30. Specifically, there may be multiple clamping members, and the multiple clamping members are arranged at intervals. Or the clamping member may be in a closed loop shape, so as to clamp and fix the expansion membrane 30 along the circumference of the expansion membrane 30. Of course, the clamping member may also be in a non-closed loop shape.

[0068] The film expansion jig 10 is configured to separate the die 21 in the wafer 20 fixed on the separation platform through the expansion film 30. The driving component is connected to the film expansion jig 10 and is configured to drive the film expansion jig 10 to move up and down along the first direction Y to lift the expansion film 30 fixed on the separation platform, so that the expansion film 30 is expanded, thereby separating the die 21. The driving component may include at least one driving member, which may be a motor.

[0069] The specific structure and function of the film expansion fixture 10 are described below.

[0070] See also Figure 1 and Figure 2 The film expanding fixture 10 includes a first film expanding plate 1 and at least one second film expanding plate 2 .

[0071] The first film expansion plate 1 is configured to be movable along a first direction Y to lift up the expansion film 30 fixed on the separation platform so that the expansion film 30 undergoes a first film expansion process. The wafer 20 is placed on a first side of the expansion film 30, and the first direction Y is a direction from the second side of the expansion film 30 to the first side, and the second side is relative to the first side.

[0072] Among them, after the expansion film 30 is fixed on the separation platform, the central axis of the wafer 20 coincides or almost coincides with the central axis O of the first expansion film plate 1. In this way, the expansion jig 10 can be used to separate the grains 21 in more areas of the wafer 20, thereby improving the uniformity of the force and improving the separation effect of the expansion jig 10 on the wafer 20.

[0073] In specific embodiments, see Figure 3 , Figure 3 A schematic diagram of a structure in which a first film expansion plate lifts up an expansion film along a first direction provided in an embodiment of the present application; a driving component drives the first film expansion plate 1 to move and lift up along a first direction Y, so that the expansion film 30 is lifted up relative to the supporting platform by the first film expansion plate 1. Since the circumferential edge of the expansion film 30 is fixed to the fixing component of the separation platform, and the wafer 20 is attached to the expansion film 30; therefore, after the middle area of ​​the expansion film 30 is lifted up, the wafer 20 is also lifted up, so that the grains 21 to be separated on the wafer 20 are separated.

[0074] The shape of the first film expansion plate 1 matches the shape of the wafer 20, and the maximum area of ​​the first film expansion plate 1 is equal to or nearly equal to the area of ​​the wafer 20, so that after the wafer 20 and the first film expansion plate 1 are coaxially arranged, it can be ensured that the first film expansion plate 1 can perform film expansion processing on the entire wafer 20. In some embodiments, the maximum area of ​​the first film expansion plate 1 is smaller than the area of ​​the wafer 20.

[0075] At least one second film expansion plate 2 is respectively configured to be electrically connected to the driving component, and the driving component can drive each second film expansion plate 2 to rise relative to the first film expansion plate 1 along the first direction Y to further lift the expansion film 30, so that the expansion film 30 undergoes at least one second film expansion process until the plurality of grains 21 of the wafer 20 on the expansion film 30 are completely separated. Among them, each second film expansion plate 2 can be configured to rise or fall independently along the first direction Y.

[0076] See also Figure 4 , Figure 4 for Figure 3 Schematic diagram of the structure in which the expansion film 30 is lifted by a second film expansion plate 2; after the first film expansion process, the first film expansion plate 1 can be kept in a lifted state; then the second film expansion plate 2 is configured to be lifted relative to the first film expansion plate 1 along the first direction Y. It can be understood that during the entire separation process, the total lifting height of the second film expansion plate 2 relative to the carrier along the first direction Y is greater than the total lifting height of the first film expansion plate 1 relative to the carrier along the first direction Y. In this way, compared to only setting the first film expansion plate 1, by adding at least one second film expansion plate 2, the height of the expansion film 30 lifted along the first direction Y and the number of times the film expansion process is performed on the wafer 20 can be increased, so as to more effectively separate the grains 21.

[0077] In one embodiment, the cross-sectional area of ​​each second film expansion disk 2 is smaller than the cross-sectional area of ​​the first film expansion disk 1. In this way, during the second film expansion process, the second film expansion disk 2 can be used to expand the film in a targeted manner on a local area of ​​the wafer 20 through the expansion film 30, thereby more effectively separating the die 21. It should be noted that the cross-sectional area of ​​the film expansion disk involved in this patent refers to the area of ​​the entire area surrounded by the outer edge of the film expansion disk.

[0078] In one embodiment, in combination Figure 1 The first film expansion disk 1 may be in a hollow ring shape; that is, the first film expansion disk 1 has a hollow area. The second film expansion disk 2 is arranged along the direction close to the central axis O of the first film expansion disk 1, and all the second film expansion disks 2 of the film expansion fixture 10 are sequentially sleeved in the hollow area of ​​the first film expansion disk 1, that is, all the second film expansion disks 2 are sleeved in a ring, and the first film expansion disk 1 is sleeved on the outside of all the second film expansion disks 2.

[0079] The two adjacent film expansion plates may contact each other, or there may be a certain gap between the two adjacent film expansion plates, so that the friction force generated by the contact between the two film expansion plates can be prevented from hindering the lifting process of the film expansion plates.

[0080] In one embodiment, see Figure 5 , Figure 5 for Figure 4 Schematic diagram of the structure in which the expansion film 30 in the structure shown is lifted up by another second expansion film plate 2; the number of the second expansion film plates 2 can be one or more. The cross-sectional areas of the multiple second expansion film plates 2 are different, and all the second expansion film plates 2 are coaxially arranged with the first expansion film plate 1. It can be understood that the cross-sectional areas of the multiple second expansion film plates 2 gradually decrease along the direction close to the central axis O of the first expansion film plate 1. In this way, the second expansion film plate 2 with gradually decreasing cross-sectional areas can be used to sequentially perform a second expansion film treatment on each area of ​​the wafer 20 from the edge to the center using the expansion film 30 to separate the grains 21 in the small area, thereby further improving the separation effect of the grains 21.

[0081] In some embodiments, when the film expansion jig 10 includes two second film expansion plates 2, along the direction close to the central axis O of the first film expansion plate 1, the ratio of the cross-sectional area of ​​the two second film expansion plates 2 to the cross-sectional area of ​​the first film expansion plate 1 can be two-thirds and one-third, or other suitable values. When the film expansion jig 10 includes three second film expansion plates 2, along the direction close to the central axis O of the first film expansion plate 1, the ratio of the cross-sectional area of ​​the three second film expansion plates 2 to the cross-sectional area of ​​the first film expansion plate 1 can be three-quarters, two-quarters and one-quarter, or other suitable values, and so on.

[0082] Among them, combined Figures 3 to 5In the process of separating the crystal grains 21, the total lifting height of each second film expansion plate 2 relative to the carrier along the first direction Y is negatively correlated with the cross-sectional area of ​​the second film expansion plate 2. In other words, the closer the second film expansion plate 2 is to the central axis O of the first film expansion plate 1, the greater the total lifting height of the second film expansion plate 2 relative to the carrier along the first direction Y. In this way, by gradually increasing the lifting height of the second film expansion plate 2, the crystal grains 21 at the corresponding positions can be separated more effectively, so as to separate the crystal grains 21 in the central area of ​​the wafer 20 as much as possible.

[0083] It should be noted that the total lifting height of the second film expansion plate 2 relative to the supporting platform along the first direction Y involved in the present application may be less than or equal to the maximum height that the second film expansion plate 2 can be lifted along the first direction Y. The maximum height that the second film expansion plate 2 can be lifted along the first direction Y refers to the maximum height that the driving member can drive the second film expansion plate 2 to reach along the first direction Y relative to the supporting platform.

[0084] In a specific embodiment, in combination Figures 3 to 5 The driving assembly can sequentially drive the plurality of second film expansion plates 2 to rise relative to the first film expansion plate 1 in the order in which the cross-sectional areas of the second film expansion plates 2 gradually decrease. The driving assembly can include a plurality of driving members, one driving member correspondingly connected to a first film expansion plate 1 or a second film expansion plate 2, so as to drive the first film expansion plate 1 or the second film expansion plate 2 to move up and down independently along the first direction Y.

[0085] In a specific embodiment, the number of the second film expansion disk 2 is specifically two, namely a large film expansion disk and a small film expansion disk, the large film expansion disk and the small film expansion disk have different cross-sectional areas, and the large film expansion disk is annularly sleeved on the outside of the small film expansion disk, and the first film expansion disk 1 is annularly sleeved on the outside of the large film expansion disk. In the specific working process, the first film expansion disk 1, the large film expansion disk and the small film expansion disk can be driven to rise simultaneously relative to the bearing platform along the first direction Y. Then the large film expansion disk and the small film expansion disk are driven to further lift up relative to the first film expansion disk 1; and then the small film expansion disk is driven to further lift up relative to the large film expansion disk. It can be understood that the total lifting height of the large film expansion disk relative to the bearing platform is greater than the total lifting height of the first film expansion disk 1 relative to the bearing platform; the total lifting height of the small film expansion disk relative to the bearing platform is greater than the total lifting height of the large film expansion disk relative to the bearing platform.

[0086] In some embodiments, a second film expansion disk 2 closest to the central axis O of the first film expansion disk 1 is a solid disk; in this way, each position in the central area of ​​the wafer 20 can be expanded by the second film expansion disk 2 to increase the probability that the grains 21 in the central area of ​​the wafer 20 can be separated.

[0087] The cross-sectional area of ​​the second film expansion disk 2 closest to the central axis O of the first film expansion disk 1 is not greater than 9 mm 2; For example, the cross-sectional area of ​​the solid disk may be 9mm 2 , 8mm 2 , 7mm 2 、6mm 2 , 5mm 2 , 4mm 2 , 3mm 2 , 2mm 2 , 1mm 2 In this way, the second film expansion disk 2 can be used to expand the cross-sectional area of ​​less than 9mm 2 The crystal grains 21 are separated, so that the film expansion fixture 10 has a wider application range.

[0088] The remaining second film expansion disks 2 are all hollow ring-shaped; specifically, they can be hollow closed ring-shaped. When the film expansion fixture 10 is idle, that is, not lifted up, multiple second film expansion disks 2 in the shape of hollow closed rings are sequentially sleeved on the circumferential outer side of the second film expansion disk 2 of the solid disk.

[0089] Specifically, the first film expansion disk 1 and the second film expansion disk 2 in a hollow ring shape can both be hollow discs. The first film expansion disk 1 and all the second film expansion disks 2 can form a solid disc. The thickness and material of the second film expansion disk 2 can be the same or similar to the material of the first film expansion disk 1. Specifically, the thickness of the second film expansion disk 2 can be the same as the thickness of the first film expansion disk 1. In this way, in the process of manufacturing the film expansion jig 10, the first film expansion disk 1 and at least one second film expansion disk 2 can be formed separately on the same film expansion disk through a cutting process or other separation processes, which is simple to manufacture and low in cost.

[0090] In one embodiment, see Figure 6 , Figure 6 A schematic structural diagram of a second film expansion plate provided in an embodiment of the present application; each second film expansion plate 2 includes a plurality of film expansion blocks 2a along its circumferential direction, the plurality of film expansion blocks 2a are independently arranged, and each film expansion block 2a is configured to be independently raised or lowered.

[0091] The sizes of the multiple film expansion blocks 2a can be the same or different, or some can be the same and some can be different. In some embodiments, one film expansion block 2a can be connected to a corresponding driving member to independently drive the film expansion block 2a to rise or fall relative to the supporting platform.

[0092] It can be understood that when the second film expanding disk 2 is a solid disk, each film expanding block 2 a can be in a fan-shaped structure and contact at the center of the corresponding second film expanding disk 2 .

[0093] Among them, two adjacent film expansion blocks 2a can contact each other; or there can be a certain gap between two adjacent film expansion blocks 2a, so that the friction generated by the contact between the two film expansion blocks 2a can be prevented from hindering the rising or lowering process of the film expansion block 2a. The length of the film expansion block 2a along the circumferential direction of the second film expansion disk 2 can be set according to actual conditions, and this application does not limit this.

[0094] The film expansion fixture 10 provided in this embodiment includes a first film expansion plate 1, and the first film expansion plate 1 is configured to be movable along the first direction Y to lift up the expansion film 30 fixed on the separation platform, so that the expansion film 30 undergoes the first film expansion treatment; at the same time, the film expansion fixture 10 further sets at least one second film expansion plate 2, and at least one second film expansion plate 2 is configured to be able to rise relative to the first film expansion plate 1 along the first direction Y to further lift up the expansion film 30, so that the expansion film 30 undergoes at least one second film expansion treatment; compared with the solution that only includes one first film expansion plate 1 for one film expansion treatment, the film expansion fixture 10 can increase the lifting height of the expansion film 30, and increase the number of film expansion treatments on the wafer 20, which can effectively increase the film expansion of the central part of the wafer 20, thereby more effectively separating the grains 21. Moreover, each film expansion process can increase the spacing between the separated grains 21, giving the unseparated grains 21 to be separated more film expansion space, so that the method can separate multiple grains 21 to be separated with smaller areas, and has a wider range of applications. At the same time, the method is compatible with products where the grains 21 to be separated cannot be completely separated by a single film expansion after the wafer 20 is invisible cut. In addition, the film expansion fixture 10 can use the second film expansion plate 2 with a gradually decreasing cross-sectional area to perform a second film expansion process on each area of ​​the wafer 20 from the edge to the center in turn using the expansion film 30 to separate the grains 21 with a smaller area, thereby further improving the separation effect of the grains 21. In addition, by gradually increasing the height of the top of the second film expansion plate 2, the grains 21 at the corresponding position can be separated more effectively, so as to separate the grains 21 in the central area of ​​the wafer 20 as much as possible.

[0095] In another embodiment, see Figure 7 and Figure 8 , Figure 7 A schematic structural diagram of a first film expansion disk provided in another embodiment of the present application; Figure 8 Schematic diagram of the structure of a film expansion jig 10 provided in another embodiment of the present application. Another film expansion jig 10 is provided, which is similar to the above Figures 1 to 5 The film expansion jig 10 provided in the corresponding embodiment is different in that the first film expansion plate 1 has at least one through hole 11. Each through hole 11 penetrates the first side surface and the second side surface of the first film expansion plate 1. There are multiple second film expansion plates 2, and multiple second film expansion plates 2 are adjacently or spaced apart in these through holes 11.

[0096] In one embodiment, the first film expansion plate 1 has a through hole 11; a plurality of second film expansion plates 2 are arranged in the through hole 11. Two adjacent second film expansion plates 2 may contact each other. Or there may be a certain gap between two adjacent second film expansion plates 2, that is, two adjacent second film expansion plates 2 are completely spaced apart.

[0097] In another embodiment, the first film expansion disk 1 has a plurality of through holes 11 , and the plurality of through holes 11 are arranged at intervals; and a second film expansion disk 2 is arranged in one through hole 11 .

[0098] In this embodiment, the cross-sectional areas of the plurality of second film expansion disks 2 may be the same or different, or the cross-sectional areas of some second film expansion disks 2 may be the same, and the cross-sectional areas of some second film expansion disks 2 may be different.

[0099] In this embodiment, the cross-sectional area of ​​each second expansion disk 2 is not greater than 9 mm 2 For example, the cross-sectional area of ​​the second expansion disk 2 may be 9mm 2 , 8mm 2 , 7mm 2 、6mm 2 , 5mm 2 , 4mm 2 , 3mm 2 , 2mm 2 , 1mm 2 In this way, these second expansion disks 2 can be used to expand the cross-sectional area of ​​less than 9mm 2 The crystal grains 21 are separated, so that the film expansion fixture 10 has a wider application range.

[0100] In some embodiments, Figure 8 As shown, the ratio of the sum of the cross-sectional areas of all the second film expansion plates 2 to the cross-sectional area of ​​the first film expansion plate 1 is 0.9-1; for example, the ratio may be 0.9, 0.92, 0.95, 0.97 or 1, etc. In this way, after the first film expansion process, no matter which area of ​​the wafer 20 where the dies 21 are not separated, the film expansion process can be continued by the second film expansion plate 2 of the film expansion fixture 10 to further separate the dies 21.

[0101] In this embodiment, see Fig. 9 and Fig.10 , Fig. 9 A schematic diagram of the structure of a wafer after a first film expansion process provided by another embodiment of the present application; Fig.10 To use Figure 8 A second film expansion plate in the film expansion fixture is Fig. 9After the wafer 20 has undergone the first film expansion process by the first film expansion plate 1, if there are still some grains 21 that have not been separated at a local position of the wafer 20, such as position M, then Fig.10 As shown, the second film expansion plate 2 corresponding to the M position can be driven to rise independently to lift up the expansion film 30 , thereby performing a second film expansion process on the crystal grain 21 at the M position to separate the crystal grain 21 at this position.

[0102] That is, the plurality of second film expansion plates 2 are configured to be able to be raised or lowered individually, so as to perform the second film expansion process on the unseparated dies 21 in certain specific areas of the wafer 20, thereby separating the dies 21 at the corresponding positions. Of course, the plurality of second film expansion plates 2 can also be configured to be driven simultaneously, so as to perform the second film expansion process on the dies 21 in most areas of the wafer 20 at the same time through these second film expansion plates 2.

[0103] Among them, the lifting heights of the multiple second film expansion plates 2 can be the same or different, and can be designed according to actual needs.

[0104] With the above Figure 1 Compared with the film expansion jig 10 provided in the corresponding embodiment, the film expansion jig 10 provided in this embodiment can not only perform the second film expansion treatment on the grains 21 in most areas of the wafer 20, but also can perform the film expansion treatment on the grains 21 in local areas of the wafer 20 separately, so as to further improve the separation effect of the grains 21.

[0105] In some embodiments, the separation platform further includes an image collector (not shown), which is configured to obtain image information of the wafer 20 and determine the region information of the to-be-separated region of the wafer 20 based on the image information. The image collector may be a camera. The grains 21 in the to-be-separated region have not been completely separated. The region information includes position information and / or the degree of separation of the grains 21. The position information may be coordinate information.

[0106] The driving component is electrically connected to the image collector. The driving component drives the second film expansion disk 2 at the corresponding position to be lifted relative to the first film expansion disk 1 along the first direction Y based on the position information to perform a second film expansion process; and / or drives the second film expansion disk 2 at the corresponding position to be lifted relative to the first film expansion disk 1 along the first direction Y to a preset height based on the separation degree of the crystal grains 21. The separation degree of a crystal grain corresponds to a preset height; the specific corresponding relationship can be preset in advance. It should be noted that the "preset height" here is the lifting height of each second film expansion disk 2 relative to the first film expansion disk 1.

[0107] See also Fig.11 , Fig.11A flow chart of a method for separating grains provided in one embodiment of the present application; In this embodiment, a method for separating grains is provided, and the separation method can include the above Figure 1 The separation platform of the film expansion fixture 10 provided in the corresponding embodiment is implemented. The relevant introduction of the film expansion fixture 10 can be found above. The grain separation method includes:

[0108] Step S1: fix a wafer on a separation platform through an expansion film, wherein the wafer has a plurality of dies to be separated formed after cutting, and the wafer is placed on a first side of the expansion film.

[0109] The wafer 20 is clamped and fixed on the fixing component of the separation platform by the expansion film 30 .

[0110] See also Fig.12 , Fig.12 A schematic diagram of the structure of a wafer 20 provided in an embodiment of the present application. The wafer 20 has a cutting path. In some embodiments, the wafer 20 may include a substrate 22 and a dielectric layer 23 disposed on the substrate 22. The substrate 22 may be any suitable base material known in the art, for example, at least one of the following materials: silicon (Si), germanium (Ge), silicon germanium (SiGe), carbon silicon (SiC), carbon germanium silicon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP) or other III / V compound semiconductors, including multilayer structures composed of these semiconductors, or silicon on insulator (SOI), stacked silicon on insulator (SSOI), stacked silicon germanium on insulator (S-SiGeOI), silicon germanium on insulator (SiGeOI) and germanium on insulator (GeOI). The material of the dielectric layer 23 may be the same as or different from that of the substrate 22.

[0111] A metal structure 24 is provided in the dielectric layer 23. The metal structure 24 may be a structure known to those skilled in the art for electrical connection, such as a hybrid bonding structure, a metal bump, a through silicon via structure, a redistribution layer, a metal layer, etc. The metal structure 24 may be located in the device region to form a device. The side of the metal structure 24 facing away from the substrate 22 may be exposed from the dielectric layer 23 so that the metal structure 24 may be electrically connected to other devices in subsequent processes.

[0112] The surface of the dielectric layer 23 facing away from the substrate 22 is the front side of the wafer 20 , and the surface of the substrate 22 facing away from the dielectric layer 23 is the back side of the wafer 20 .

[0113] In the specific implementation process, the back side of the wafer 20 is firstly facing the expansion film 30. Then, the wafer 20 is cut by stealth cutting to form a plurality of dies 21 to be separated.

[0114] Specifically, the expansion film 30 can be pressed on the back of the wafer 20 by vacuum lamination. The laser invisible cutting method can be used to invisible cut the cutting area of ​​the wafer 20 from the side where the front of the wafer 20 is located. The following embodiments of the present application are introduced by taking this as an example.

[0115] Of course, in other embodiments, an extended film 30 may be set on the front side of the wafer 20, and then the wafer 20 may be cut from the side where the back side of the wafer 20 is located by using an invisible cutting method; or the wafer 20 may be cut from the side where the back side of the wafer 20 is located by using a plasma process.

[0116] The diameter of the expansion film 30 is larger than the diameter of the wafer 20, so as to ensure that the wafer 20 can be fixed on the separation platform through the expansion film 30, and to ensure that the expansion film 30 has sufficient strength for subsequent expansion. The expansion film 30 is made of a material with good ductility. For example, the expansion film 30 can be made of polyethylene (poly) material.

[0117] Step S2: driving the first film expanding plate of the film expanding fixture of the separation platform to lift the expanded film along the first direction Y, so that the expanded film undergoes a first film expanding treatment to separate the grains on the expanded film; wherein the first direction is from the second side of the expanded film to the first side, and the second side is relative to the first side.

[0118] Combination Figures 2 to 3 In the specific implementation process, the first film expansion plate 1 is driven by the driving component to rise relative to the supporting platform along the first direction Y, so as to lift the expansion film 30 along the first direction Y, thereby separating the grains 21 arranged on the expansion film 30.

[0119] In one embodiment, in combination Figure 3 While driving the first film expansion plate 1 to rise, all the second film expansion plates 2 on the film expansion fixture 10 can be synchronously driven to rise synchronously relative to the carrier platform along the first direction Y, so as to use at least one second film expansion plate 2 to synchronously lift the expansion film 30 and perform the first film expansion process on the wafer 20, so that the film expansion process can separate more grains 21 on the wafer 20 and improve the film expansion efficiency. Among them, the lifting heights of the first film expansion plate 1 and all the second film expansion plates can be the same.

[0120] Of course, in another embodiment, step S2 may also only drive the first film expanding plate 1 to rise along the first direction Y relative to the supporting platform, and all the second film expanding plates 2 remain stationary along the first direction Y relative to the supporting platform.

[0121] Step S3: driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one second film expanding process; wherein the second film expanding plate can be lifted relative to the first film expanding plate along the first direction.

[0122] In the process of executing step S3, the first film expansion disk 1 still remains in a raised state.

[0123] In one embodiment, in combination Figures 4 to 5 The step of driving at least one second film expanding plate 2 of the film expanding fixture 10 to further lift the expanded film 30 along the first direction Y relative to the first film expanding plate 1 includes:

[0124] Step S31: in the order in which the cross-sectional area of ​​at least one second film expanding plate 2 of the film expanding fixture 10 gradually decreases, at least one second film expanding plate 2 is driven in sequence to further lift the expanded film 30 along the first direction Y relative to the first film expanding plate 1 .

[0125] It can be understood that the total lifting height of the second film expanding plate 2 relative to the supporting platform is greater than the total lifting height of the first film expanding plate 1 relative to the supporting platform.

[0126] In some embodiments, the total lifting height of the second film expansion plate 2 relative to the supporting platform along the first direction Y is negatively correlated with the cross-sectional area of ​​the second film expansion plate 2. In this way, during the execution of step S31, by gradually increasing the lifting height of the second film expansion plate 2, the dies 21 at the corresponding positions can be more effectively separated, so as to separate the dies 21 in the central area of ​​the wafer 20 as much as possible.

[0127] Take the film expansion fixture 10 including two second film expansion plates 2, namely a large film expansion plate and a small film expansion plate as an example, and combine Figures 4 to 5 In the process of executing step S31, see Figure 4 The large film expansion plate and the small film expansion plate can be driven to rise relative to the first film expansion plate 1 along the first direction Y so as to Figure 3 The state shown further lifts the expansion film 30, so that the expansion film 30 undergoes a second expansion process. Figure 5 , driving the small film expansion disk to further rise relative to the large film expansion disk along the first direction Y, so as to Figure 4 The state shown further lifts the expansion film 30, so that the expansion film 30 undergoes the next second expansion process. Figures 3 to 5 It can be understood that the total lifting height of the large film expansion plate relative to the supporting platform is greater than the lifting height of the first film expansion plate 1; the total lifting height of the small film expansion plate relative to the supporting platform is greater than the total lifting height of the large film expansion plate relative to the supporting platform.

[0128] Of course, in the process of driving the large film expansion plate to rise, you can choose to synchronously drive the small film expansion plate and the large film expansion plate to rise to the same height relative to the first film expansion plate 1 along the first direction Y; or you can choose to only drive the large film expansion plate to rise, and the small film expansion plate can be protected relative to the first film expansion plate 1.

[0129] Of course, in the specific implementation process, if there are still unseparated grains 21 on the wafer 20, the wafer 20 can continue to be subjected to the second film expansion treatment for the third, fourth or even more times until the grains 21 on the wafer 20 are completely separated.

[0130] In this embodiment, the second film expansion plate 2 with a gradually decreasing cross-sectional area can be used to sequentially perform a second film expansion process on each region from the edge to the center of the wafer 20 using the expansion film 30, so as to gradually separate the grains 21 with a smaller area, thereby further improving the separation effect of the grains 21. At the same time, by gradually increasing the jacking height of the second film expansion plate 2, the grains 21 at the corresponding positions can be separated more effectively, so as to separate the grains 21 in the central region of the wafer 20 as much as possible.

[0131] In one embodiment, after step S31, the method further includes:

[0132] Step S32 ′: driving the film expansion block 2 a at the preset position to further lift the expansion film 30 along the first direction Y relative to the second film expansion plate 2 where the film expansion block 2 a is located, so that the expansion film 30 undergoes at least one third film expansion process.

[0133] In the specific implementation process, if the grains 21 in the preset position area have not been completely separated, the above solution can be used to further separate the grains 21 in a smaller area using the expansion block 2 a to achieve complete separation of each grain 21 .

[0134] For ease of understanding, the second film expansion disk 2 of the outermost circle is taken as an example to explain "the film expansion block 2a further lifts the expansion film 30 relative to the second film expansion disk 2 where the film expansion block 2a is located along the first direction Y". The second film expansion disk 2 of the outermost circle includes multiple film expansion blocks 2a. If the part of the crystal grains 21 corresponding to the second film expansion disk 2 of the outermost circle has not been completely separated, the part of the film expansion blocks 2a of the second film expansion disk 2 of the outermost circle is driven to further lift the expansion film 30 relative to the plane where the second film expansion disk 2 of the outermost circle is located, so as to perform a third film expansion process on the crystal grains 21 at the corresponding positions.

[0135] In the specific implementation process, each film expansion block 2a can be driven to rise along the first direction Y relative to the second film expansion plate 2 where the film expansion block 2a is located, so as to separate the grains 21 of a certain area of ​​the wafer 20. When the grains 21 of multiple different areas of the wafer 20 are not completely separated, the film expansion blocks 2a at the corresponding positions can be driven to rise at the same time to perform the third film expansion process respectively. The film expansion blocks 2a at each position can also be driven to rise in sequence, so as to perform the third film expansion process on each position in sequence.

[0136] Of course, in the process of driving the second film expansion plate 2 to lift the expansion film 30 along the first direction Y relative to the first film expansion plate 1 to perform the second film expansion process, some film expansion blocks 2a in the second film expansion plate 2 can also be driven to lift the expansion film 30 along the first direction Y relative to the first film expansion plate 1 to save energy consumption of the driving component.

[0137] In another embodiment, after step S31, the method further includes:

[0138] Step S32 : unlocking the wafer 20 from the separation platform and re-fixing the wafer 20 on another separation platform via the expansion film 30 .

[0139] Among them, another separation platform can be provided by the above embodiment including Figure 8 The separation platform of the film expansion fixture 10 shown in FIG. When the wafer 20 is fixed to another separation platform through the expansion film 30, the unseparated grains 21 on the wafer 20 are at least corresponding to one third film expansion plate. The third film expansion plate can be Figure 8 The second film expansion plate 2 or similar in the film expansion fixture 10 shown Figure 8 The second film expanding plate 2 in the film expanding fixture 10 is shown.

[0140] Step S33: driving at least one third film expanding plate of the film expanding fixture 10 of another separation platform to further lift the expanded film 30 relative to the first film expanding plate 1 along the first direction Y, so that the expanded film 30 undergoes at least one third film expanding process until the multiple grains 21 on the expanded film 30 are completely separated.

[0141] Among them, at least one third film expansion disk is adjacent or spaced apart, and the central axes of every two third film expansion disks are spaced apart; that is, any two third film expansion disks are not coaxially arranged. The cross-sectional area of ​​each third film expansion disk is smaller than the cross-sectional area of ​​any second film expansion disk 2; in this way, the third film expansion disk can be used to further separate the grains 21 in a smaller area, so as to achieve complete separation of each grain 21.

[0142] In the specific implementation process, each third film expansion plate can be driven to rise relative to the carrier platform along the first direction Y to separate the grains 21 in a certain area of ​​the wafer 20. When the grains 21 in multiple different areas of the wafer 20 are not completely separated, the third film expansion plates at the corresponding positions can be driven to rise at the same time to perform the third film expansion process respectively. The third film expansion plates at each position can also be driven to rise in sequence to perform the third film expansion process on each position in sequence.

[0143] In some embodiments, during the execution of step S33, the orthographic projection of at least one third film expansion disk on the wafer 20 is at least located at other positions of the wafer 20 that are different from the central position of the wafer 20; to ensure that the grains 21 located at other positions of the wafer 20 that are different from the central position of the wafer 20 can be subjected to the third film expansion treatment through the third film expansion disk to further separate these grains 21.

[0144] In another embodiment, the separation method of the grains can be used alone to include Figure 8 The separation platform of the film expansion fixture 10 provided in the corresponding embodiment is implemented. Figure 8 The relevant introduction of the film expansion fixture 10 provided in the corresponding embodiment can be found above. Fig. 9 and Fig.10 The grain separation method is different from the grain separation method provided in the above embodiment in that step S3 specifically includes:

[0145] Step S31 ′: driving at least one second film expanding plate 2 of the film expanding fixture 10 to simultaneously or sequentially lift up relative to the first film expanding plate 1 along the first direction Y, so that the expanded film 30 undergoes at least one second film expanding process until the plurality of grains 21 on the expanded film 30 are completely separated.

[0146] Among them, combined Figure 8 There are multiple second film expansion plates 2, and the multiple second film expansion plates 2 are adjacent or spaced apart, and the central axes of every two second film expansion plates 2 are spaced apart, that is, any two second film expansion plates 2 are not coaxially arranged.

[0147] In this embodiment, with respect to the positions of the dies 21 on the wafer 20 that have not been separated, part of the second film expansion plate 2 can be driven to rise to lift up the expansion film 30 at the corresponding positions, thereby separating the dies 21 at the corresponding positions.

[0148] If there are multiple dies 21 on the wafer 20 that have not been separated, each of the unseparated dies 21 corresponds to a second film expansion plate 2. In the specific separation process, the second film expansion plates 2 can be driven to rise sequentially or synchronously by the driving component. The driving component can drive multiple second film expansion plates 2 to rise or fall independently, so as to control the lifting height of each second film expansion plate 2.

[0149] In the specific implementation process, if the unseparated grains 21 are still not completely separated after the second film expansion process, the lifting height of the second film expansion plate 2 can be increased to more effectively separate the grains 21. Of course, if the second film expansion process is sufficient to separate the grains 21 within a certain height range, the lifting heights of the second film expansion plates 2 can be the same or different, and can be set according to actual conditions.

[0150] In this embodiment, not only can the second film expansion process be performed on the grains 21 in most areas of the wafer 20 by using multiple second film expansion plates 2, but also the second film expansion process can be performed separately on the unseparated grains 21 in specific areas of the wafer 20 to separate the grains 21 in the specific areas.

[0151] In a specific implementation process, the method for separating grains provided in any of the above embodiments further includes:

[0152] Step S4: acquiring image information of the wafer 20, and determining region information of the to-be-separated region of the wafer 20 based on the image information, wherein the grains 21 in the to-be-separated region have not been completely separated; and the region information includes position information.

[0153] The above step S4 may be performed by an image collector, which may be a camera. The position information may be coordinate information.

[0154] Step S5: Based on the position information, the second film expanding plate 2 at the corresponding position is driven to be lifted up relative to the first film expanding plate 1 along the first direction Y to perform a second film expanding process.

[0155] Among them, one piece of position information corresponds to one second film expansion disk 2 .

[0156] In one embodiment, the region information further includes the degree of separation of the grains; the method for separating the grains provided in any of the above embodiments further includes:

[0157] Step S6: Based on the separation degree of the crystal grains 21 , the second film expansion plate 2 at the corresponding position is driven to lift up a preset height relative to the first film expansion plate 1 along the first direction Y; wherein the separation degree of one crystal grain corresponds to one preset height.

[0158] The method for separating the grains provided in any of the above embodiments may include one or both of step S5 and step S6 after step S4. In the specific implementation process, the above step S5 and / or step S6 may be performed by a driving component electrically connected to the image collector. The driving component may drive each second film expansion disk 2 to rise or fall independently.

[0159] The method for separating the grains provided in this embodiment drives the first film expansion plate 1 of the film expansion fixture 10 of the separation platform to lift the expansion film 30 along the first direction Y, so that the expansion film 30 undergoes the first film expansion treatment to separate the grains 21 on the expansion film 30; then further drives at least one second film expansion plate 2 of the film expansion fixture 10 to further lift the expansion film 30 relative to the first film expansion plate 1 along the first direction Y, so that the expansion film 30 undergoes at least one second film expansion treatment. This not only increases the lifting height of the expansion film 30, and increases the number of times the film expansion treatment is performed on the wafer 20, but can also effectively increase the film expansion of the central part of the wafer 20, thereby more effectively separating the grains 21; and each film expansion treatment can increase the spacing between the separated grains 21, giving the unseparated grains 21 to be separated more film expansion space, so that the method can separate multiple grains 21 to be separated with a smaller area, and has a wider range of applications. At the same time, the method is compatible with products where the grains 21 to be separated cannot be completely separated by a single film expansion after the wafer 20 is invisible cut.

[0160] The above are only implementation methods of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for separating crystal grains, characterized in that: include: Fixing a wafer on a separation platform through an expansion film, wherein the wafer has a plurality of dies to be separated formed after cutting, and the wafer is placed on a first side of the expansion film; Driving the first film expansion plate of the film expansion fixture of the separation platform to lift the expansion film along a first direction, so that the expansion film undergoes a first film expansion process to separate the grains on the expansion film; wherein the first direction is a direction from the second side of the expansion film to the first side, and the second side is relative to the first side; Drive at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one second film expanding treatment; wherein the second film expanding plate can be lifted relative to the first film expanding plate along the first direction.

2. The method for separating crystal grains according to claim 1, characterized in that: The step of driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction comprises: According to the order in which the cross-sectional area of ​​at least one second film expanding plate of the film expanding fixture gradually decreases, the at least one second film expanding plate is driven in sequence to further lift the expanded film relative to the first film expanding plate along the first direction; wherein, the at least one second film expanding plate is coaxially arranged with the first film expanding plate; and the cross-sectional area of ​​each of the second film expanding plates is smaller than the cross-sectional area of ​​the first film expanding plate.

3. The method for separating crystal grains according to claim 2, characterized in that: The total lifting height of the second film expanding disk relative to the supporting platform of the separation platform along the first direction is negatively correlated with the cross-sectional area of ​​the second film expanding disk.

4. The method for separating crystal grains according to claim 2, characterized in that: Each of the second film expansion plates includes a plurality of film expansion blocks along its circumferential direction, the plurality of film expansion blocks are independently arranged, and each of the film expansion blocks is configured to be independently raised or lowered; After the step of driving at least one second film expanding plate of the film expanding jig to further lift the expanded film relative to the first film expanding plate along the first direction so that the expanded film undergoes at least one second film expanding treatment, the step further includes: driving the film expanding block at a preset position to further lift the expanded film relative to the second film expanding plate where the film expanding block is located along the first direction so that the expanded film undergoes at least one third film expanding treatment.

5. The method for separating crystal grains according to claim 2, characterized in that: After the step of driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction so that the expanded film undergoes at least one second film expanding process, the method further includes: unlocking the wafer from the separation platform and re-fixing the wafer to another separation platform via the expansion film; Drive at least one third film expanding plate of the film expanding fixture of the other separation platform to further lift the expanded film relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one third film expanding treatment; wherein, the at least one third film expanding plate is adjacent or spaced apart, and the central axes of every two third film expanding plates are spaced apart; the cross-sectional area of ​​each third film expanding plate is smaller than the cross-sectional area of ​​any second film expanding plate.

6. The method for separating crystal grains according to claim 5, characterized in that: The orthographic projection of the at least one third film expansion disk on the wafer is at least located at another position of the wafer different from the central position of the wafer.

7. The method for separating crystal grains according to claim 1, characterized in that: The step of driving at least one second film expanding plate of the film expanding fixture to further lift the expanded film relative to the first film expanding plate along the first direction so that the expanded film undergoes at least one second film expanding process comprises: Drive at least one second film expanding plate of the film expanding fixture to simultaneously or sequentially lift up relative to the first film expanding plate along the first direction, so that the expanded film undergoes at least one second film expanding treatment; wherein, the at least one second film expanding plate is adjacent or spaced apart, and the central axes of every two second film expanding plates are spaced apart; and the cross-sectional area of ​​each second film expanding plate is smaller than the cross-sectional area of ​​the first film expanding plate.

8. The method for separating crystal grains according to any one of claims 1 to 7, characterized in that: Also includes: Acquire image information of the wafer, and determine region information of a to-be-separated region of the wafer based on the image information; wherein the grains in the to-be-separated region have not been completely separated; and the region information includes position information; Based on the position information, the second film expansion disk at the corresponding position is driven to be lifted up relative to the first film expansion disk along the first direction to perform the second film expansion process.

9. The method for separating crystal grains according to claim 8, characterized in that The region information also includes the separation degree of the grains; the method further includes: Based on the separation degree of the crystal grains, the second film expansion disk at the corresponding position is driven to be lifted up to a preset height relative to the first film expansion disk along the first direction; wherein the separation degree of one crystal grain corresponds to one preset height.

10. A film expansion jig, applied to a separation platform to separate grains in a wafer fixed on the separation platform by an expansion film, characterized in that: The film expansion fixture includes: a first film expansion plate, configured to be movable along a first direction to lift up the expansion film fixed on the separation platform so that the expansion film undergoes a first film expansion process, wherein the wafer is placed on a first side of the expansion film, the first direction is a direction from a second side of the expansion film to the first side, and the second side is relative to the first side; At least one second film expansion plate is configured to be able to rise relative to the first film expansion plate along the first direction to further lift the expansion film.

11. The film expansion jig according to claim 10, characterized in that: The cross-sectional area of ​​each of the second film expansion disks is smaller than the cross-sectional area of ​​the first film expansion disk.

12. The film expansion jig according to claim 11, characterized in that: There are multiple second film expanding plates; the cross-sectional areas of the multiple second film expanding plates are different, and the multiple second film expanding plates are coaxially arranged with the first film expanding plate.

13. The film expansion jig according to claim 12, characterized in that: The first film expanding disk is in a hollow ring shape; along a direction close to the central axis of the first film expanding disk, a plurality of the second film expanding disks are sequentially sleeved in the hollow area of ​​the first film expanding disk.

14. The film expansion jig according to claim 13, characterized in that: Among the plurality of second film expanding disks, the second film expanding disk closest to the central axis of the first film expanding disk is a solid disk; and the other second film expanding disks are all hollow ring-shaped.

15. The film expansion jig according to claim 12, characterized in that: Each of the second film expanding plates includes a plurality of film expanding blocks along its circumferential direction. The plurality of film expanding blocks are independently arranged, and each of the film expanding blocks is configured to be independently raised or lowered.

16. The film expansion jig according to claim 12, characterized in that: The cross-sectional area of ​​the smallest second film expansion disk among the plurality of second film expansion disks is not greater than 9 mm 2 .

17. The film expansion jig according to claim 11, characterized in that: There are multiple second film expanding plates, and the multiple second film expanding plates are arranged adjacent to or at intervals, and the central axes of every two second film expanding plates are arranged at intervals.

18. The film expansion jig according to claim 17, characterized in that: The first film expansion plate has at least one through hole; the through hole penetrates the first side surface and the second side surface of the first film expansion plate; There are multiple second film expansion plates, and the multiple second film expansion plates are arranged in the at least one through hole.

19. The film expansion jig according to claim 17, characterized in that: The ratio of the sum of the cross-sectional areas of all the second film expansion disks to the cross-sectional area of ​​the first film expansion disk is 0.9-1.

20. A separation platform, characterized in that: It comprises the film expansion jig as described in any one of claims 10 to 19.

Images