Separation method of crystal grain, crystal grain and crystal grain packaging body
By adopting the inclined cutting method during the wafer cutting process, the problem of grains being subjected to a greater force during the cutting process is solved, and the grain quality and reliability of the packaging are improved.
Patent Information
- Application Number
- CN202411804396.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-09
- Publication Date
- 2025-03-28
AI Technical Summary
During the wafer cutting process, the grains are subjected to a greater force, which affects the grain quality.
The wafer is cut by an inclined cutting method to ensure that at least one of the multiple cuts corresponding to each grain is arranged inclined with respect to the first surface of the wafer.
By tilting cutting, the stress that the grains are perpendicular to the wafer thickness direction is reduced, the grain quality is improved, and the contact area between the grains and the packaging substrate is increased, thereby improving product reliability.
Smart Images
Figure CN119725229A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of semiconductor technology, and in particular to a method for separating crystal grains, crystal grains and a crystal grain package. Background Art
[0002] In the packaging process, the wafer needs to be cut into multiple single dies along the cutting path. However, in the current cutting process, the dies are subjected to a large force during the cutting process, which affects the quality of the dies. Summary of the invention
[0003] The present application provides a method for separating a die, a die and a die package, aiming to solve the problem that the die is subjected to a large force during the cutting process, thereby affecting the quality of the die.
[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 providing a wafer; the wafer comprising a plurality of grains to be separated; the wafer having a first surface and a second surface opposite to each other;
[0005] The wafer is cut multiple times along a first direction and a second direction respectively to divide the wafer into multiple grains; wherein the first direction intersects with the second direction; in the multiple cuts corresponding to each grain, the cutting direction of at least one cut is inclined relative to the first surface of the wafer.
[0006] In one embodiment of the present application, when the wafer is cut multiple times along the first direction, the cutting direction of each cutting is inclined relative to the first surface of the wafer; and / or
[0007] When the wafer is cut multiple times along the second direction, the cutting direction of each cutting is inclined relative to the first surface of the wafer.
[0008] In one embodiment of the present application, along the first direction, the cutting directions of every two adjacent cuttings are parallel to each other; and / or
[0009] Along the second direction, the cutting directions of every two adjacent cuttings are parallel to each other.
[0010] In one embodiment of the present application, the wafer has a plurality of cutting lanes, and the orthographic projection of a cutting path formed by each cutting on the wafer is located within the cutting lane.
[0011] In one embodiment of the present application, the wafer is cut by mechanical cutting.
[0012] In order to solve the above technical problems, another technical solution adopted in the present application is: providing a grain, which has a first face and a second face opposite to each other and a first side face and a second side face opposite to each other along a first direction; the area of the first face of the grain is less than or equal to the area of the second face of the grain; the first side face and the second side face are respectively connected between the first face of the grain and the second face of the grain, and the first side face and / or the second side face are inclined relative to the first face of the grain.
[0013] In one embodiment of the present application, the first side surface and the second side surface are both inclined relative to the first surface of the grain; and the first side surface and the second side surface are parallel to each other.
[0014] In one embodiment of the present application, the grain also has a third side surface and a fourth side surface opposite to each other along a second direction, and the second direction intersects with the first direction; the third side surface and the fourth side surface are respectively connected between the first side surface of the grain and the second side surface of the grain, and the third side surface and the fourth side surface are respectively located between the first side surface and the second side surface along the circumferential direction of the grain; wherein the third side surface and / or the fourth side surface are inclined relative to the first side surface of the grain.
[0015] In one embodiment of the present application, the third side surface and the fourth side surface are both inclined relative to the first surface of the grain; and the third side surface and the fourth side surface are parallel to each other.
[0016] In one embodiment of the present application, the first side of the grain is parallel to the second side of the grain; and along the first direction, the first length of the first side of the grain is equal to the second length of the second side of the grain; and / or along the second direction, the third length of the first side of the grain is equal to the fourth length of the second side of the grain.
[0017] In one embodiment of the present application, the angle between one or more of the first side surface, the second side surface, the third side surface and the fourth side surface and the first side of the grain is greater than or equal to 45° and less than or equal to 80°.
[0018] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a grain package, which includes: a packaging substrate; the grain involved above, which is arranged on the packaging substrate and electrically connected to the packaging substrate; and a packaging layer, which encapsulates the grain and part of the packaging substrate therein.
[0019] The beneficial effects of the embodiments of the present application are different from those of the prior art: the method for separating the grains provided by the embodiments of the present application, in the process of cutting the wafer multiple times along the first direction and the second direction respectively to divide the wafer into multiple grains, the cutting direction of at least one of the multiple cuts corresponding to each grain is set obliquely relative to the first surface of the wafer; compared with the scheme in which the cutting direction is set perpendicularly to the first surface of the wafer, under the action of the same cutting force, according to the principle of force decomposition, the force on the grain along the direction perpendicular to the thickness direction of the wafer can be reduced, and the quality of the grain is effectively improved. Moreover, the oblique cutting can increase the area of the side of the grain formed by the cutting, so that in the process of packaging the grain with the packaging substrate, the contact area between the grain and the bonding layer and / or the packaging layer can be increased, thereby effectively increasing the bonding force between the grain and the bonding layer and / or the packaging layer, and further improving the product reliability. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] 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 used 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:
[0021] Figure 1 A flow chart of a method for separating grains provided in one embodiment of the present application;
[0022] Figure 2 A schematic plan view of a wafer provided in one embodiment of the present application;
[0023] Figure 3 for Figure 2 The cross-sectional view of the wafer shown in the PP' direction;
[0024] Figure 4 A schematic diagram of a process for cutting a wafer provided in an embodiment of the present application;
[0025] Figure 5 for Figure 4 The force decomposition diagram of the grain during the cutting process is shown;
[0026] Figure 6 The experience provided by an embodiment of the present application Figure 1 A schematic cross-sectional view of the grain obtained by cutting in step S2;
[0027] Figure 7 A cross-sectional schematic diagram of a chip package provided in an embodiment of the present application.
[0028] Description of Reference Numerals
[0029] 10 crystal grain; 1a first surface; 1b second surface; 1c first side surface; 1d second side surface; 1e third side surface; 1f fourth side surface; 11 substrate; 12 metal layer; 13 sealing ring; 14 cutting path; 20 cutting road; 30 bonding film; 40 packaging substrate; 50 packaging layer; 60 adhesive layer. DETAILED DESCRIPTION
[0030] 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.
[0031] 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.
[0032] 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.
[0033] In the related art, a vertical cutting process is usually used to cut the wafer, that is, the cutting direction is perpendicular to the surface of the wafer to separate multiple grains. However, during the cutting process, the grains to be separated on the wafer, such as the seal ring on the grain, will be subjected to a large force, affecting the product quality.
[0034] To this end, an embodiment of the present application provides a method for separating grains, which can reduce the force on the grains during the wafer cutting process and effectively improve the quality of the grains.
[0035] The present application is described in detail below with reference to the accompanying drawings and embodiments.
[0036] See also Figure 1 , Figure 1 A 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, the method comprising:
[0037] Step S1: providing a wafer; the wafer comprises a plurality of dies to be separated; the wafer has a first surface and a second surface opposite to each other.
[0038] See also Figure 2 , Figure 2 A schematic plan view of a wafer provided in an embodiment of the present application; the wafer has a plurality of cutting lanes 20, and the plurality of cutting lanes 20 divide the wafer into a plurality of dies 10 to be separated. Part of the cutting lanes 20 extend along the first direction X and are arranged at intervals along the second direction Y; and part of the cutting lanes 20 extend along the second direction Y and are arranged at intervals along the first direction X.
[0039] See also Figure 3 , Figure 3 for Figure 2 The wafer is a cross-sectional view in the PP' direction. The wafer may include a substrate 11 and a metal layer 12 disposed on the substrate 11. The first surface 1a of the wafer refers to a surface of the metal layer 12 facing away from the substrate 11, and the second surface 1b of the wafer refers to a surface of the substrate 11 facing away from the metal layer 12. The metal layer 12 is a layer containing a metal structure.
[0040] The substrate 11 may be any suitable base material known in the art, for example, it may be 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).
[0041] It should be noted that the "M component" involved in this application is arranged on the "N component", which means that the M component is arranged on one side of the N component, and it is not required that the M component is directly attached to the N component. Other film layer structures may be arranged between the M component and the N component. For example, the metal layer 12 is arranged on the substrate 11, which means that the metal layer 12 is located on one side of the substrate 11, and the metal layer 12 may be directly attached to the first surface 1a of the substrate 11; or other film layer structures may be arranged between the metal layer 12 and the substrate 11, and this application does not limit this.
[0042] Step S2: cutting the wafer multiple times along the first direction and the second direction respectively to divide the wafer into multiple grains; wherein the first direction intersects with the second direction; in the multiple cuts corresponding to each grain, the cutting direction of at least one cut is inclined relative to the first surface of the wafer.
[0043] The first direction X and the second direction Y may be perpendicular to each other, that is, the angle between the first direction X and the second direction Y is 90°. Of course, the angle between the first direction X and the second direction Y may also be 45°, 60°, 80°, 85° or 89°, etc.
[0044] See also Figure 4 and Figure 5 , Figure 4 A schematic diagram of a process for cutting a wafer provided in an embodiment of the present application; Figure 5 for Figure 4 The force decomposition diagram of the die 10 during the cutting process is shown; the orthographic projection of the cutting path 14 formed by each cutting along the thickness direction Z of the wafer on the first surface 1a of the wafer falls within the cutting path 20, so that the consistency of the cut chip area can be ensured. Among them, the "cutting path 14" refers to the entire gap left on the wafer after cutting.
[0045] In some specific implementations, when the cutting direction is inclined relative to the first surface 1a of the wafer, the angle α between the cutting direction and the first surface 1a of the wafer may be greater than or equal to 45° and less than or equal to 80°; for example, the angle α may be 45°, 60°, 70° or 80°, etc. It should be noted that when the cutting path formed by cutting the wafer is a curve along the thickness direction Z of the wafer, the cutting direction involved in this application refers to the extension direction of the tangent line tangent to the curve.
[0046] In the specific implementation process, combined with Figure 4 , the bonding film 30 can be attached to the second surface 1b of the wafer first. Then the wafer is cut from the side where the first surface 1a of the wafer is located, and the cutting ends at the surface of the bonding film 30 facing the wafer. The product structure after cutting can be seen in Figure 5 The following description will be made by taking the bonding film 30 being bonded to the second surface 1 b of the wafer as an example.
[0047] Of course, in other embodiments, the laminating film 30 may be attached to the first surface 1a of the wafer first. Then, the wafer is cut from the side where the second surface 1b of the wafer is located, and the cutting ends at the surface of the laminating film 30 facing the wafer. The laminating film 30 may be pressed on the first surface 1a or the second surface 1b of the wafer by vacuum laminating. The laminating film 30 may be made of a material including polyethylene (poly).
[0048] In the specific implementation process, the cutting path 20 of the wafer can be cut by mechanical cutting to form a plurality of grains 10. Mechanical cutting can be, for example, knife cutting. Among them, by cutting the wafer by mechanical cutting, the substrate 11 and the metal layer 12 of the wafer can be completely cut through a single cutting process, without the need to separate the metal layer 12 through other cutting processes again, thereby simplifying the process and accelerating the separation efficiency. Of course, in other embodiments, laser cutting can also be used for cutting.
[0049] In the specific implementation process, combined with Figure 2 , the plurality of dicing streets 20 on the wafer can be cut along the first direction X, and the plurality of dicing streets 20 on the wafer can be cut along the second direction Y, so as to completely separate the plurality of dies 10 to be separated on the wafer to form a plurality of single dies 10. The order of cutting along the first direction X and along the second direction Y is not limited.
[0050] It is understood that each die 10 needs to be cut multiple times to separate the die 10 from the wafer. In a specific implementation process, the number of cuts corresponding to cutting each die 10 is four. Among the four cuts corresponding to each die 10, the cutting direction of at least one cut is inclined relative to the first surface 1a of the wafer.
[0051] Combination Figure 5 , Figure 5 for Figure 4The force decomposition diagram of the die 10 during the cutting process is shown; compared with the solution in which the cutting direction is set perpendicular to the first surface 1a of the wafer, the above-mentioned inclined cutting solution, under the action of the same cutting force F, according to the force decomposition principle, the force acting on the die 10 in the direction perpendicular to the thickness direction Z of the wafer is F1, and F1 is less than F. Therefore, this solution effectively reduces the force of the die 10 in the direction perpendicular to the thickness direction Z of the wafer, reduces the force of the seal ring 13 (seal ring) on the wafer for protecting the die 10, and effectively improves the quality of the die 10. In addition, the inclined cutting can increase the area of the side surface of the die 10 formed by cutting, so that in the process of packaging the die 10 with the packaging substrate 40, the contact area between the die 10 and the adhesive layer 60 and / or the packaging layer 50 can be increased, thereby effectively increasing the bonding force between the die 10 and the adhesive layer 60 and / or the packaging layer 50, and further improving the product reliability.
[0052] In some embodiments, see Figure 6 , Figure 6 The experience provided by an embodiment of the present application Figure 1 Schematic diagram of the cross section of the crystal grain 10 obtained by cutting in step S2; when the wafer is cut multiple times along the first direction X, the cutting direction of each cutting is tilted relative to the first surface 1a of the wafer; that is, for each cutting along the first direction X, the angle α between the cutting direction and the first surface 1a of the wafer is greater than 0° and less than 90°. In this way, for each crystal grain 10 formed by cutting, the first side surface 1c and the second side surface 1d disposed opposite to each other along the first direction X are tilted relative to the first surface 1a of the crystal grain 10; this solution effectively increases the area of the first side surface 1c and the second side surface 1d of the crystal grain 10.
[0053] In another embodiment, when the wafer is cut multiple times along the second direction Y, the cutting direction of each cutting is tilted relative to the first surface 1a of the wafer; that is, for each cutting along the second direction Y, the angle α between the cutting direction and the first surface 1a of the wafer is greater than 0° and less than 90°. In this way, for each crystal grain 10 formed by cutting, the third side surface 1e and the fourth side surface 1f disposed opposite to each other along the second direction Y are tilted relative to the first surface 1a of the crystal grain 10; this solution also effectively increases the area of the third side surface 1e and the fourth side surface 1f of the crystal grain 10.
[0054] In another embodiment, when the wafer is cut multiple times along the first direction X, the cutting direction of each cut is tilted relative to the first surface 1a of the wafer; and when the wafer is cut multiple times along the second direction Y, the cutting direction of each cut is also tilted relative to the first surface 1a of the wafer; in this way, the total area of the side surface of the grain 10 can be maximized, thereby effectively increasing the bonding force between the grain 10 and the packaging layer 50, and improving the reliability of the grain package.
[0055] In some embodiments, see Figure 6 , Figure 6 The experience provided by an embodiment of the present application Figure 1 Schematic diagram of the cross section of the crystal grain 10 obtained by cutting in step S2; along the first direction X, the cutting directions of each two adjacent cuttings are parallel to each other. In this way, there is no need to readjust the cutting angle for each cutting along the first direction X, which is convenient for assembly line cutting and speeds up the cutting efficiency of the wafer; and in this way, the two side surfaces of the crystal grain 10 formed by cutting along the first direction X are parallel to each other, and on the basis that the first surface 1a and the second surface 1b of the wafer are parallel to each other, it can be ensured that the first length L1 of the first surface 1a of the crystal grain 10 along the first direction X is the same as the second length L2 of the second surface 1b of the crystal grain 10 along the first direction X, thereby obtaining a plurality of regular crystal grains 10.
[0056] In other embodiments, the cutting directions of two adjacent cuts along the second direction Y are parallel to each other. Similarly, there is no need to readjust the cutting angle for each cut along the second direction Y, and assembly line cutting can be achieved, further speeding up the wafer cutting efficiency; and in this way, the two side surfaces of the grain 10 formed by cutting along the second direction Y are also parallel to each other, and on the basis that the first surface 1a and the second surface 1b of the wafer are parallel to each other, it can be ensured that the third length L3 of the first surface 1a of the grain 10 along the second direction Y is also the same as the fourth length L4 of the second surface 1b of the grain 10 along the second direction Y.
[0057] In some other embodiments, along the first direction X, the cutting directions of every two adjacent cuts are parallel to each other; and along the second direction Y, the cutting directions of every two adjacent cuts are also parallel to each other.
[0058] The method for separating the dies 10 provided in this embodiment comprises providing a wafer; then cutting the wafer multiple times along a first direction X and a second direction Y respectively to divide the wafer into multiple dies 10; wherein, in the process of cutting the wafer multiple times along the first direction X and the second direction Y respectively to divide the wafer into multiple dies 10, the cutting direction of at least one of the multiple cuttings corresponding to each dies 10 is set obliquely relative to the first surface 1a of the wafer; compared with the solution in which the cutting direction is set perpendicularly to the first surface 1a of the wafer, under the action of the same cutting force, according to the principle of force decomposition, the force on the dies 10 along the direction perpendicular to the thickness direction Z of the wafer can be reduced, thereby effectively improving the quality of the dies 10. Moreover, the oblique cutting can increase the area of the side surface of the dies 10 formed by the cutting, so that in the process of packaging the dies 10 with the packaging substrate 40, the contact area between the dies 10 and the adhesive layer and / or the packaging layer 50 can be increased, thereby effectively increasing the bonding force between the dies 10 and the adhesive layer and / or the packaging layer 50, further improving the product reliability.
[0059] In one embodiment, see Figure 6 , providing a crystal grain 10, which can be separated by the above-mentioned crystal grain separation method. The crystal grain 10 has a first face 1a and a second face 1b opposite to each other, and a first side face 1c and a second side face 1d opposite to each other along a first direction X; the first side face 1c and the second side face 1d are respectively connected between the first face 1a of the crystal grain 10 and the second face 1b of the crystal grain 10.
[0060] In some embodiments, the area of the first surface 1a of the die 10 is less than or equal to the area of the second surface 1b of the die 10. In this way, during the packaging process, the contact area between the second surface 1b of the die 10 and the packaging layer 50 can be increased, thereby improving the bonding force between the second surface 1b of the die 10 and the packaging layer 50, and effectively improving the stability of the die package. Of course, in some embodiments, the area of the first surface 1a of the die 10 separated by the above-mentioned die separation method can also be greater than the area of the second surface 1b of the die 10.
[0061] In some embodiments, the area of the first surface 1a of the die 10 is equal to the area of the second surface 1b of the die 10. In a specific embodiment, the first surface 1a of the die 10 is parallel to the second surface 1b of the die 10; and along the first direction X, the first length L1 of the first surface 1a of the die 10 is equal to the second length L2 of the second surface 1b of the die 10.
[0062] In some embodiments, the first side surface 1c is tilted relative to the first surface 1a of the die 10; that is, the angle β1 between the first side surface 1c of the die 10 and the first surface 1a of the die 10 is greater than 0° and less than 90°. Specifically, the angle β1 may be greater than or equal to 45° and less than or equal to 80°.
[0063] In another embodiment, the second side surface 1d is tilted relative to the first surface 1a of the grain 10; that is, the angle β2 between the second side surface 1d of the grain 10 and the first surface 1a of the grain 10 is greater than 0° and less than 90°. Specifically, the angle β2 may be greater than or equal to 45° and less than or equal to 80°. The angles β1 and / or β2 involved in the present application may be 45°, 60°, 70°, or 80°, etc.
[0064] In yet another embodiment, the first side surface 1 c and the second side surface 1 d are both inclined relative to the first surface 1 a of the die 10 .
[0065] In some embodiments, the first side surface 1 c and the second side surface 1 d of the die 10 are both inclined relative to the first surface 1 a of the die 10 ; and the first side surface 1 c and the second side surface 1 d of the die 10 are parallel to each other.
[0066] The crystal grain 10 also has a third side surface 1e and a fourth side surface 1f opposite to each other along the second direction Y. The third side surface 1e and the fourth side surface 1f are respectively connected between the first side surface 1a and the second side surface 1b; and the third side surface 1e and the fourth side surface 1f are respectively located between the first side surface 1c and the second side surface 1d along the circumferential direction of the crystal grain 10. Along the circumferential direction of the crystal grain 10, the third side surface 1e is located between the first side surface 1c and the second side surface 1d, and the fourth side surface 1f is also located between the first side surface 1c and the second side surface 1d.
[0067] The second direction Y intersects the first direction X. The first direction X and the second direction Y may be perpendicular to each other, that is, the angle between the first direction X and the second direction Y is 90°. Of course, the angle between the first direction X and the second direction Y may also be 45°, 60°, 80°, 85° or 89°, etc.
[0068] In some embodiments, the third side surface 1e is tilted relative to the first surface 1a of the die 10; that is, the angle β1 between the third side surface 1e of the die 10 and the first surface 1a of the die 10 is greater than 0° and less than 90°. In this embodiment, the angle β1 can be greater than or equal to 45° and less than or equal to 80°.
[0069] In another embodiment, the fourth side surface 1f is tilted relative to the first surface 1a of the grain 10; that is, the angle β2 between the fourth side surface 1f of the grain 10 and the first surface 1a of the grain 10 is greater than 0° and less than 90°. In this embodiment, the angle β2 can be greater than or equal to 45° and less than or equal to 80°.
[0070] In yet another embodiment, the third side surface 1 e and the fourth side surface 1 f are both inclined relative to the first surface 1 a of the die 10 .
[0071] In some embodiments, the third side surface 1e and the fourth side surface 1f of the die 10 are both inclined relative to the first side surface 1a of the die 10 ; and the third side surface 1e and the fourth side surface 1f of the die 10 are parallel to each other.
[0072] In this embodiment, along the second direction Y, the third length L3 of the first side 1a of the crystal grain 10 and the fourth length L4 of the second side 1b of the crystal grain 10 may also be equal. In the present application, only the first length L1 and the second length L2 may be equal, and the third length L3 and the fourth length L4 may not be equal; the first length L1 and the second length L2 may not be equal, and the third length L3 and the fourth length L4 may be equal; or the first length L1 and the second length L2 may be equal, and the third length L3 and the fourth length L4 may also be equal.
[0073] In some embodiments, any one or more of the four side surfaces, the first side surface 1c to the fourth side surface 1f, may be tilted relative to the first surface 1a of the grain 10. For example, the first side surface 1c and the second side surface 1d are tilted relative to the first surface 1a of the grain 10; the third side surface 1e and the fourth side surface 1f are non-tilted relative to the first surface 1a of the grain 10. Or the first side surface 1c and the second side surface 1d are non-tilted relative to the first surface 1a of the grain 10; the third side surface 1e and the fourth side surface 1f are tilted relative to the first surface 1a of the grain 10. Or the first side surface 1c and the third side surface 1e are tilted relative to the first surface 1a of the grain 10; the second side surface 1d and the fourth side surface 1f are non-tilted relative to the first surface 1a of the grain 10, and so on.
[0074] The die 10 provided in this embodiment effectively increases the area of the first side surface 1c and / or the second side surface 1d of the die 10 by tilting the first side surface 1c and / or the second side surface 1d relative to the first side surface 1a of the die 10; thereby, during the packaging process, the bonding force between the first side surface 1c and / or the second side surface 1d of the die 10 and the packaging layer 50 and the adhesive layer 60 is improved, and the reliability of the die package is effectively improved. At the same time, by making the area of the second side 1b of the die 10 greater than or equal to the area of the first side 1a, the contact area between the die 10 and the packaging layer 50 can be further increased, so as to further improve the bonding force between the die 10 and the packaging layer 50.
[0075] In one embodiment, see Figure 7 , Figure 7 A schematic cross-sectional view of a grain package provided in one embodiment of the present application. In this embodiment, a grain package is provided, and the grain package includes a packaging substrate 40, a grain 10, and a packaging layer 50. The grain 10 is disposed on the packaging substrate 40 and is electrically connected to the packaging substrate 40. The grain 10 may be the grain 10 provided in any of the above embodiments or may be separated by the separation method of the grain 10 provided in any of the above embodiments, and the specific introduction may be found above. The packaging layer 50 encapsulates the grain 10 and part of the packaging substrate 40 therein. The material of the packaging layer 50 includes silicon dioxide or epoxy resin.
[0076] In one embodiment, the package substrate 40 may include a leadframe. The leadframe includes a die support sheet and a plurality of pins. The die support sheet is used to provide mechanical support for the die 10 during the packaging process. In one embodiment, a plurality of pins may be arranged around the die support sheet. In this embodiment, the die 10 is arranged on the die support sheet and is electrically connected to the plurality of pins. The die support sheet and the pins may be made of an iron (Fe)-nickel (Ni) alloy or a copper-based alloy.
[0077] In another embodiment, the package substrate 40 includes a package carrier having a first surface and a second surface opposite to each other. At least one connection line is disposed in the package carrier, and at least part of the connection line is exposed on the first surface and / or the second surface of the package carrier. In this embodiment, the die 10 is disposed on the package carrier and is electrically connected to at least one corresponding connection line.
[0078] In one embodiment, see Figure 7 The die package further includes an adhesive layer 60, which is disposed between the die 10 and the package substrate 40 and is used to stably connect the die 10 to the package substrate 40 and improve the connection stability between the die 10 and the package substrate 40. The adhesive may be an epoxy resin adhesive.
[0079] The chip package provided in this embodiment has a large contact area between the chip 10 and the packaging layer 50 and / or the adhesive layer 60, which effectively increases the bonding force between the chip 10 and the packaging layer 50 and / or the adhesive layer 60, further improving the reliability of the chip package.
[0080] The above description is only an implementation method of the present application, and does not 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 used 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: Provide wafers; The wafer includes a plurality of dies to be separated; The wafer has a first surface and a second surface opposite to each other; Cutting the wafer multiple times along a first direction and a second direction respectively to divide the wafer into a plurality of crystal grains; wherein the first direction intersects with the second direction; In the multiple cuts corresponding to cutting to form each of the crystal grains, a cutting direction of at least one cut is tilted relative to the first surface of the wafer.
2. The method for separating crystal grains according to claim 1, characterized in that: In cutting the wafer multiple times along the first direction, the cutting direction of each cutting is inclined relative to the first surface of the wafer; and / or When the wafer is cut multiple times along the second direction, the cutting direction of each cutting is inclined relative to the first surface of the wafer.
3. The method for separating crystal grains according to claim 2, characterized in that: Along the first direction, the cutting directions of every two adjacent cuts are parallel to each other; and / or Along the second direction, the cutting directions of every two adjacent cuttings are parallel to each other.
4. The method for separating crystal grains according to claim 2, characterized in that: The wafer has a plurality of dicing streets, and the orthographic projection of a dicing path formed by each dicing on the wafer is located within the dicing street.
5. The method for separating crystal grains according to any one of claims 1 to 4, characterized in that: The wafer is cut by mechanical cutting.
6. A crystal grain, characterized in that: The grain has a first face and a second face opposite to each other and a first side face and a second side face opposite to each other along a first direction; an area of the first face of the grain is less than or equal to an area of the second face of the grain; the first side face and the second side face are respectively connected between the first face of the grain and the second face of the grain, and the first side face and / or the second side face are arranged obliquely relative to the first face of the grain.
7. The crystal grain according to claim 6, characterized in that The first side surface and the second side surface are both inclined relative to the first surface of the grain; and the first side surface and the second side surface are parallel to each other.
8. The crystal grain according to claim 6 or 7, characterized in that: The grain also has a third side surface and a fourth side surface opposite to each other along a second direction, and the second direction intersects with the first direction; the third side surface and the fourth side surface are respectively connected between the first side surface of the grain and the second side surface of the grain, and the third side surface and the fourth side surface are respectively located between the first side surface and the second side surface along the circumferential direction of the grain; wherein the third side surface and / or the fourth side surface are inclined relative to the first side surface of the grain.
9. The crystal grain according to claim 8, characterized in that The third side surface and the fourth side surface are both inclined relative to the first surface of the grain; and the third side surface and the fourth side surface are parallel to each other.
10. The crystal grain according to claim 9, characterized in that The first side of the grain is parallel to the second side of the grain; and along the first direction, the first length of the first side of the grain is equal to the second length of the second side of the grain; and / or along the second direction, the third length of the first side of the grain is equal to the fourth length of the second side of the grain.
11. The grain according to claim 8, characterized in that An angle between one or more of the first side surface, the second side surface, the third side surface and the fourth side surface and the first surface of the grain is greater than or equal to 45° and less than or equal to 80°.
12. A chip package, characterized in that: include: Package substrate; The die according to any one of claims 6 to 11, disposed on the packaging substrate and electrically connected to the packaging substrate; The packaging layer is used to package the die and part of the packaging substrate.