Packaging structure

Abstract

Some embodiments of the present application provide a package structure, comprising: a first substrate; a wafer disposed on the first substrate; the second substrate is positioned above the wafer and is provided with a heat dissipation area; the molding compound is located between the first substrate and the second substrate and wraps the wafer, and the molding compound and the insulating layer of the heat dissipation area are overlapped in the horizontal direction. According to the packaging structure provided by the invention, the binding force between the second substrate and the molding compound is improved, and layering of the corresponding packaging structure is avoided.

Description

Technical Field

[0001] An embodiment of the present application relates to a packaging structure. Background Art

[0002] In the hybrid bonding structure (HBPOP) 10, as Figure 1A and Figure 1B As shown, the lower substrate 12 is bonded to the upper substrate 11 through a solder joint 15, and a molding compound 13 for sealing the tube core 14 is filled between the lower substrate 12 and the upper substrate 11. In addition, an external connector 16 is formed on the side of the lower substrate 12 opposite to the upper substrate and other tube cores 17, such as active or passive tube cores, are attached. As the tube core 14 of the wireless access point (AP) is improved in function, the existing hybrid bonding structure 10 has a problem of heat dissipation. Although the upper substrate 11 can improve the heat dissipation effect S (such as adding a heat dissipation pattern Figure 1B As shown in the figure, increasing the exposed area of ​​the thermal pad 11M (such as metal) will relatively reduce the area of ​​the dielectric material 11D, thereby reducing the contact area between the molding compound 13 and the dielectric material 11D of the upper substrate. If the surface of the upper substrate 11 is not covered with a dielectric layer (such as green paint) and a larger surface of the thermal pad 11M such as copper is exposed, the risk of delamination of the hybrid bonding structure 10 will often increase. This is because the bonding of the molding material of the molding compound 13 and the metal surface such as the copper surface or the gold surface (such as the surface of the thermal pad 11M) is purely dependent on physical action.

[0003] Currently, there are two main ways to increase the bonding force: 1. Increasing the roughness of metal surfaces such as copper surfaces (such as the surface of thermal pad 11M) to increase the surface area to strengthen the force; 2. Using chemical substances to strengthen the bonding with the material, but these two methods are not easy to achieve in process control. Utility Model Content

[0004] In order to solve the problem that the thermal pad of the upper substrate of the existing hybrid bonding structure has a larger exposed surface (such as a copper metal surface) and a smaller contact area with the dielectric material, resulting in poor bonding with the molding compound and delamination, the problem can be solved by increasing the contact area between the molding compound and the dielectric material of the upper substrate.

[0005] Some embodiments of the present application provide a packaging structure, comprising: a first substrate; a chip disposed on the first substrate; a second substrate located above the chip and having a heat dissipation area; and a molding compound located between the first substrate and the second substrate and covering the chip, wherein the molding compound overlaps with an insulating layer of the heat dissipation area in a horizontal direction.

[0006] In some embodiments, the molding compound extends through at least one insulating layer of the heat sink region.

[0007] In some embodiments, a groove is formed on the second substrate at the heat dissipation area, wherein the chip is disposed in the groove.

[0008] In some embodiments, the package structure further includes: a heat dissipation pattern located in the heat dissipation area and in contact with the molding compound.

[0009] In some embodiments, the heat dissipation pattern is located over the molding compound.

[0010] In some embodiments, the molding compound penetrates through the insulating layer of the heat dissipation region.

[0011] In some embodiments, the portion of the molding compound extending through the insulating layer has a groove shape.

[0012] In some embodiments, the groove shape is a tapered shape in a direction toward the wafer.

[0013] In some embodiments, the portion of the molding compound penetrating the insulating layer of the heat dissipation region has a groove shape, wherein a middle portion of the groove shape is narrower than ends at opposite ends.

[0014] In some embodiments, the packaging structure further includes: a heat dissipation pattern penetrating the insulating layer of the heat dissipation area and disposed between the molding compounds.

[0015] In some embodiments, the packaging structure further includes: a through hole disposed outside the heat dissipation area and surrounding the molding compound.

[0016] In some embodiments, the wafer is spaced apart from the second substrate by the molding compound.

[0017] In some embodiments, the molding compound extends continuously at an upper surface of the wafer proximate to the second substrate.

[0018] In some embodiments, the molding compound and the insulating layer of the heat dissipation region form an anchoring and locking structure.

[0019] In some embodiments, the portion of the molding compound extending through the insulating layer has a sidewall with a metal layer disposed thereon.

[0020] In some embodiments, the package structure further includes: a dielectric layer disposed at a surface of the second substrate close to the wafer, wherein the molding compound further extends through the dielectric layer.

[0021] In some embodiments, the molding compound extends through a portion of the insulating layer of the heat sink region.

[0022] Other embodiments of the present application also provide a packaging structure, comprising: a first substrate; a second substrate located above the first substrate and connected to the first substrate via a solder joint; a chip disposed between the first substrate and the second substrate; and a molding compound located between the first substrate and the second substrate and covering the chip, wherein the second substrate has a heat dissipation area located directly above the chip, and wherein the molding compound extends into an insulating layer of the heat dissipation area.

[0023] In some embodiments, the molding compound extends through at least a portion of the insulating layer of the heat sink region.

[0024] In some embodiments, a groove is formed on the second substrate at the heat dissipation area, wherein the chip is disposed in the groove.

[0025] The packaging structure provided in the present application improves the bonding force between the second substrate and the molding compound, and avoids delamination of the corresponding packaging structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] When read in conjunction with the accompanying drawings, various aspects of the present invention can be best understood from the following detailed description. It should be noted that, in accordance with standard practice in the industry, the various components are not drawn to scale. In fact, for the sake of clarity of discussion, the size of the various components can be arbitrarily increased or reduced.

[0027] Figure 1A to Figure 1B The package structure in the prior art is shown.

[0028] Figures 2A to 4B A packaging structure according to some embodiments of the present application is shown.

[0029] FIG. 5A to FIG. 5C as well as Figures 6 to 14 The diagram shows a process for forming a packaging structure according to some embodiments of the present application. DETAILED DESCRIPTION

[0030] The following disclosure provides many different embodiments or examples for realizing different features of the present invention. Specific examples of components and arrangements are described below to simplify the present invention. Of course, these are merely examples and are not intended to limit the present invention. In addition, when "approximately", "about", "substantially", "substantially", etc. are used to describe a numerical value or a numerical range, unless otherwise specified, the term is intended to cover a numerical value within ±10% of the described numerical value. For example, the term "about 5nm" covers a size range from 4.5nm to 5.5nm.

[0031] In packaging structures such as hybrid bonding structures, the bonding strength of the molding compound material between the upper and lower substrates is crucial. If the substrate surface is not covered with a dielectric layer and more metal surfaces (such as the surface of the thermal pad) are exposed, the risk of delamination will often increase. This is because the bonding between the molding compound material and the metal surface such as the copper surface or the gold surface is purely physical, so it is necessary to strengthen the bonding strength between the molding compound and the substrate.

[0032] Based on this, the present application is based on the presence of depressions caused by etching at the blind holes / through holes in the process. In the process of packaging structures such as hybrid bonding structures, these depressions will be filled with molding compounds, and if the shapes of these blind holes / through holes are filled with molding compounds, there will be a reverse effect, resulting in an anchor lock structure. Therefore, these extra depressions help to increase the bonding strength between the molding compound and the substrate. Furthermore, the development of a substrate with a cavity can further improve the bonding strength.

[0033] See also Figure 2A The present application provides a package structure 100, which includes: a first substrate 101, and a chip 104 disposed on the first substrate 101. In addition, the package structure 100 also includes a second substrate 102, which is located above the chip 104 and has a heat dissipation area D; and a mold compound 103, which is located between the first substrate 101 and the second substrate 102 and covers the chip 104, wherein the mold compound 103 overlaps with the insulating layer 102D of the heat dissipation area D in a horizontal direction H. In some embodiments, the mold compound 103 extends through at least one insulating layer 102D of the heat dissipation area, such as extending through a portion of the insulating layer 103, for example, extending through the first insulating layer 102D1 (see Figure 2A The package structure 100 and Figure 3A package structure 200 shown) or extending through the entire insulating layer 102D (see Figure 4A The packaging structure 300 is further described as Figure 2A As shown, the second substrate 102 is formed with a groove R at the heat dissipation area D, and the chip 104 is disposed in the groove R. Further, the upper surface 104s of the chip 104 close to the second substrate 102 is higher than the lower surface 101ds of the second substrate 102 facing the first substrate 101, that is, the chip 104 extends from the first substrate 101 to the groove R of the second substrate 102. It should be noted that Figure 3A The package structure 200 and Figure 4AIn the package structure 300 shown, the second substrate 102 has no groove R formed at the heat dissipation area D. In some embodiments, the package structure 100 further includes a heat dissipation pattern 102M, which is located in the heat dissipation area D and contacts the mold compound 103. In some other embodiments, the heat dissipation pattern 102M is located above the mold compound 103. In some embodiments, the package structure 100 further includes a metal line layer 102l, which is connected to the heat dissipation pattern 102M and can extend discretely or continuously above the wafer 104. Further, the mold compound 103 penetrates the insulation layer 102D / first insulation layer 102D in the heat dissipation area D. 1 , and the mold compound 103 extends through the insulating layer 102D / the first insulating layer 102D 1 The portion 103t in the middle has a groove shape, from Figure 2A and Figure 3A It can be seen from the figure that the groove shape is a tapered shape in the direction V toward the wafer. In the direction V toward the wafer, the width of the tapered shape gradually decreases. Figure 4A As shown, the portion 103t of the mold compound 103 penetrating the insulating layer 102D of the heat dissipation area D has a groove shape, and the middle portion 103tm of the groove shape is narrower than the end portions 103td at the opposite ends. Figure 4A The package structure 300 further includes a heat dissipation pattern 102M penetrating the insulation layer 102D of the heat dissipation region D and disposed between the molding compounds 103t. FIG. 2A to FIG. 4A As shown, the package structure 100-300 further includes: a through hole 102t (in the heat dissipation area D) disposed outside the heat dissipation area D and surrounding the mold compound 103 (specifically, passing through a portion 103t of the mold compound 103) Figure 2A and Figure 3A It can also be called a blind hole).

[0034] In addition, Figure 2A The package structure is 100 to Figure 4A In the package structure 300 shown, the chip 104 is separated from the second substrate 102 by the molding compound 103. In some embodiments, the molding compound 103 extends continuously at the upper surface 104s of the chip 104, and specifically, the portion 103l of the molding compound extends continuously at the upper surface 104s of the chip 104. In further embodiments, the molding compound 103 and the insulating layer 102D / 102D of the heat dissipation region D are connected to each other. 1 An anchoring structure is formed, that is, the portion 103t of the mold compound 103 and the insulating layer 102D / 102D of the heat dissipation area D 1 An anchoring structure is formed to increase the bonding force between the mold compound 103 and the second substrate 102. The mold compound 103 extends through the insulating layer 102D / the first insulating layer 102D.1 The portion 103t has a side wall 102Ds, and a metal layer (not shown) is disposed on the side wall 102Ds, which can be a shielding member in electrical design to block interference between signals.

[0035] In addition, Figure 2A The package structure is 100 to Figure 4A In the package structure 300 shown, the package structure 100-300 further includes a dielectric layer 101D, which is disposed on a surface of the second substrate 102 close to the wafer 104 and extends from the substrate 102 to the substrate 104. FIG. 2A to FIG. 4A As can be seen in FIG. 1 , the mold compound 103 further extends through the dielectric layer 101D.

[0036] In the above-mentioned package structures 100 to 300, the second substrate 102 is bonded to the first substrate 101 through the solder joint 105, and the chip 104 is attached to the first substrate 101 through the pad 104P and the adhesive layer 107 disposed at the surface 101s of the first substrate 101. FIG. 2A to FIG. 4A As shown, the pad 104P is surrounded by the underfill. In a further embodiment, the first substrate 101 is formed with external connectors 106 at the side opposite to the wafer 104 for making external connections.

[0037] In the above embodiments, the wafer 104 includes a die, a chip, etc., and the first substrate 101 and the second substrate 102 may be substrates with a redistribution structure, such as a printed circuit board, an interposer, etc. In some embodiments, the molding compound 103 may include a molding compound, a molding material, an underfill, etc. The insulating layer 102D / first insulating layer 102D1 and the second insulating layer 102D2 may be made of a dielectric material, such as silicon oxide, silicon oxynitride, etc. In other embodiments, the pad 104P, the heat dissipation pattern 102M, the metal line layer 1021, and the through hole 102t include a metal or a metal alloy such as copper, gold, silver, etc. In some embodiments, the solder joint 105 and the external connector 106 may include solder, etc.

[0038] In addition, the present application also provides a corresponding packaging structure, specifically, see further Figure 2A The package structure is 100 to Figure 4AThe package structure 300 shown in the figure comprises a first substrate 101: a second substrate 102, which is located above the first substrate 101 and has a solder joint 105 connected to the first substrate 101: a chip 104, which is disposed between the first substrate 101 and the second substrate 102; and a molding compound 103, which is located between the first substrate 101 and the second substrate 102 and covers the chip 104, wherein the second substrate 102 has a heat dissipation area D located directly above the chip 104, and the molding compound 103 extends into an insulating layer 102D of the heat dissipation area D. In some embodiments, the molding compound 103 extends through at least a portion of the insulating layer 102D of the heat dissipation area D, see Figures 2A to 3A , the portion 103t of the mold compound 103 extends through the first insulating layer 102D of the insulating layer 102D 1 , while Figure 4A In the package structure 300 shown, a portion 103t of the mold compound 103 penetrates the insulating layer 102D. Figure 2A In the package structure 100 shown, a groove R is formed in the heat dissipation area D of the second substrate 102 , wherein the chip 104 is disposed in the groove R.

[0039] In the above-mentioned package structure 100-300, the mold compound 103 extends into the insulating layer 102D to form an anchoring and locking structure, which is similar to a rivet fixing structure, and increases the bonding strength of the corresponding package structure 100-300. In addition, in addition to increasing the bonding strength between the mold compound 103 and the second substrate 102, such an anchoring and locking structure can avoid the thermal barrier of the material of the second substrate 102, and the heat source of the chip 104 can directly pass through the column path of the portion 103t of the mold compound 103, helping to achieve the effect of heat dissipation. Furthermore, the side wall 102Ds of the insulating layer 102D at the portion 103t of the mold compound 103 of the anchoring and locking structure can be plated with a metal layer, and in terms of electrical design, it can be mostly a shielding member to block interference between signals.

[0040] In addition, it is desirable to add more bonding points on the second substrate 102 to increase the bonding strength of the corresponding packaging structures 100 - 300 , just like rivets can enhance the stability of the surface steel plate.

[0041] Therefore, the rivet structure in the anchoring and locking structure formed by the molding compound 103 extending into the insulating layer 102D can be prepared by using the laser blind holes or through holes of the second substrate 102, and then the molding compound is poured into these blind holes / through holes, and because the laser holes are inverted trapezoidal shapes, an anchoring and locking effect is created, and it is expected to enhance the stability of the molding compound and the second substrate 102. Specifically,

[0042] See also Figures 2B to 4BIn all the packaging structures 100-300 such as the hybrid bonding structure, the through hole or blind hole 103o is manufactured in the second substrate 102 using the existing substrate laser method. Figure 2B and Figure 3B is shown as a blind hole, and Figure 4B Such a space (i.e., the space formed by the through hole or blind hole 103o and the cavity 103v) is reserved for the injection molding compound 103 of the package. The molding compound 103 forms an anchoring and locking structure with the corresponding insulating layer 102D in the second substrate 102 to strengthen the bonding force between the molding compound 103 and the second substrate 102.

[0043] In summary, the bars of the portion 103t of the mold compound 103 of the anchoring and locking structure can also avoid the obstruction of the material of the second substrate 102, and generate a heat conduction path to help the chip 104 dissipate heat. In addition, after the mold compound 103 is filled in the laser through hole or blind hole 103o, an anchoring and locking structure is formed, which is similar to a rivet fixing structure, and increases the bonding force of the corresponding package structure 100-300. Furthermore, the laser surface on the anchoring and locking structure, that is, the surface of the through hole or blind hole 103o, can be plated with a metal layer, and in terms of electrical design, it can be mostly a shielding member to block interference between signals.

[0044] Refer to the following FIG. 5A to FIG. 5C Let's introduce the formation of the anchoring and locking structure in detail.

[0045] See also Figure 5A , a corresponding heat dissipation pattern 102M is formed in the insulating layer 102D (the insulating layer 102D and the heat dissipation pattern 102M may be an embedded trace substrate (ETS) substrate). Figure 5B , etching the corresponding heat dissipation pattern 102M, such as Figure 5B As shown, a portion of the corresponding heat dissipation pattern 102M may be etched (without penetrating the corresponding insulating layer 102D), or the entirety of the corresponding heat dissipation pattern 102M may be etched (ie, penetrating the corresponding insulating layer 102D) to form a corresponding through hole or blind hole 103o. Figure 5C The mold compound 103 is poured into these blind holes / through holes 103o to form portions 103t and 1031 of the mold compound 103, thereby forming an anchoring locking structure.

[0046] It can be seen that, in addition to the interposer of the package structure such as the hybrid bonding structure, as long as it is an ETS substrate, the laser through hole / blind hole can be used to manufacture / form the anchoring and locking structure after pouring the molding compound 103 (glue injection). In addition, the anchoring and locking structure provided by the present application is not limited to the molding process, and is also applicable to the bottom filling process.

[0047] In summary, 1) the package structures 100-300 provided in the present application must be package structures such as hybrid structure structures, such as special structures on interposers, embedded trace substrate (ETS) substrates, etc.;

[0048] 2) For the interposer, the number of layers of the interposer substrate can be 2 or more layers. If the number of layers is 2, through holes can be designed (such as Figure 4B The through hole or blind hole 103o shown in the figure is used for injection of molding material 103; if the number of layers is greater than 2 layers or the cavity is designed as a groove R, a blind hole (such as Figure 2B and Figure 3B The through hole or blind hole 103o) shown is designed for injection of molding material 103;

[0049] 3) After the material of the molding compound 103 is filled in the laser hole (through hole or blind hole 103o) and solidified, the anchoring locking structure formed is similar to the structure fixed by rivets (the structure must be a trapezoidal shape, such as FIG. 2A to FIG. 4A As shown in FIG. 1 , in addition to increasing the bonding strength between the mold compound 103 and the second substrate 102, such an anchor lock structure can avoid thermal isolation of the second substrate 102 material, and a heat source such as a die chip 104 can directly pass through the column path of the portion 103t of the mold compound 103, thereby achieving the effect of helping to dissipate heat; and

[0050] 4) The surface of the laser hole (through hole or blind hole 103o) on the anchoring and locking structure can be plated with a layer of metal (ie, metal layer), which can be used as a shield to block interference between signals in electrical design.

[0051] Figures 6 to 14 Shown in detail Figure 2A The process flow of forming the second substrate 102 having the groove R of the package structure 100 is shown.

[0052] See also Figure 6 , providing a carrier core 1001, which may be a reinforced resin core or any other suitable carrier core. Figure 7 A metal wire layer 1021 (such as copper) is plated on the carrier core 1001 by electroplating or chemical plating. Figure 8 , a layer 1002 is formed by lamination, and the layer 1002 may be an epoxy resin layer or a dielectric layer. Next, see Fig. 9 , a through hole is formed in layer 1002 by laser, and a heat dissipation pattern 102M is plated in the through hole, and a corresponding first insulating layer 102D is formed 1 .

[0053] See also Fig.10 , a layer 1003 is formed by lamination, and the layer 1003 may also be an epoxy resin layer or a dielectric layer. Fig.11 , the carrier core 1001 is removed by a stripping process. Fig.12 , a through hole is formed in the layer 1003 by laser lithography, and a heat dissipation pattern 102M is plated in the through hole, and a corresponding second insulating layer 102D is formed 2 See also Fig.13 After forming the desired number of heat dissipation patterns 102M and the corresponding insulating layer 102D, a (SR) resist layer 102Dt is formed on the upper and lower sides of the insulating layer 102D, and an electroless nickel plating electroless palladium plating and immersion gold (ENEPIG) process is performed to improve its stability. Fig.14 , the metal line layer 1021 and the optional heat dissipation pattern 102M are etched by an etching process to form a groove R and a required blind hole or through hole (not shown, which can be determined according to actual conditions). Figure 2A As shown, the first substrate 101 with the wafer 104 attached is combined with the second substrate 102, and then the molding compound 103 is poured into the groove R and the required blind holes or through holes, so as to obtain Figure 2A The package structure 100 is shown.

[0054] The features of several embodiments are summarized above so that those skilled in the art can better understand aspects of the present invention. Those skilled in the art should understand that they can easily use the present invention as a basis to design or modify other processes and structures for implementing the same purpose and / or achieving the same advantages as the embodiments described herein. Those skilled in the art should also appreciate that such equivalent constructions do not deviate from the spirit and scope of the present invention, and that they can make various changes, substitutions, and modifications herein without departing from the spirit and scope of the present invention.

Claims

1. A packaging structure, characterized in that: include: a first substrate; A wafer, disposed on the first substrate; A second substrate, located above the chip and having a heat dissipation area; as well as a molding compound disposed between the first substrate and the second substrate and encapsulating the wafer, The molding compound overlaps the insulating layer of the heat dissipation area in a horizontal direction.

2. The packaging structure according to claim 1, characterized in that: The molding compound extends through at least one insulating layer of the heat sink region.

3. The packaging structure according to claim 1, characterized in that: The second substrate is formed with a groove at the heat dissipation area. Wherein, the wafer is arranged in the groove.

4. The packaging structure according to claim 2, characterized in that: Also includes: The heat dissipation pattern is located in the heat dissipation area and contacts the molding compound.

5. The packaging structure according to claim 4, characterized in that: The heat dissipation pattern is located over the molding compound.

6. The packaging structure according to claim 2, characterized in that: The molding compound penetrates the insulating layer of the heat dissipation area.

7. The packaging structure according to claim 5, characterized in that: A portion of the molding compound extending through the insulating layer has a groove shape.

8. The packaging structure according to claim 7, characterized in that: The groove shape is a tapered shape in a direction toward the wafer.

9. The packaging structure according to claim 6, characterized in that: The portion of the molding compound penetrating the insulating layer of the heat dissipation area has a groove shape, wherein a middle portion of the groove shape is narrower than end portions at opposite ends.

10. The packaging structure according to claim 1, characterized in that: Also includes: A through hole is disposed outside the heat dissipation area and surrounds the molding compound.

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