Package structure and method of forming the same

Abstract

The present application relates to a packaging structure and a method of forming the same. The packaging structure includes a first die, a first heat dissipation structure disposed on a surface of the first die, a second die located below the first die, a second heat dissipation structure disposed on a surface of the second die, and a heat dissipation path in contact with the surface of the first heat dissipation structure and the surface of the second heat dissipation structure.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more specifically, to a packaging structure and a method for forming the same. Background Technology

[0002] Figure 1 The diagram illustrates a 3D stacked IC (integrated circuit) 10, such as an HBM die. Current technology only adds a heat sink 14 to the upper die 12 for heat dissipation. However, the lower die 16 may suffer from ineffective heat dissipation due to the low thermal efficiency of the photoresist or molding compound 18. This can lead to overheating and performance degradation in the lower die 16. For example, the thermal conductivity of the photoresist or molding compound is approximately 0.5 W / m². -1 K -1 The thermal conductivity of copper is approximately 400 W / m². -1 K -1 The difference between the two is about 800 times. Summary of the Invention

[0003] To address the aforementioned problems in related technologies, this invention proposes a packaging structure and its formation method, which enables effective heat dissipation of the die at the bottom of the packaging structure.

[0004] An embodiment of the present invention provides a packaging structure, including: a first die; a first heat dissipation structure disposed on the surface of the first die; a second die located below the first die; a second heat dissipation structure disposed on the surface of the second die; and a heat dissipation path in contact with the surfaces of the first and second heat dissipation structures.

[0005] In some embodiments, the width of the first heat dissipation structure is different from the width of the second heat dissipation structure.

[0006] In some embodiments, the width of the second heat dissipation structure is smaller than the width of the first heat dissipation structure.

[0007] In some embodiments, the first heat dissipation structure has a first portion extending beyond the first die in the width direction, and the second heat dissipation structure has a second portion extending beyond the second die in the width direction, with a heat dissipation path connecting the lower surface of the first portion to the second portion.

[0008] In some embodiments, the heat dissipation path includes at least two metal materials, including a conductive pillar disposed above the second heat dissipation structure and a solder layer disposed above the conductive pillar.

[0009] In some embodiments, the heat dissipation path is electrically floating.

[0010] In some embodiments, the heat dissipation path is surrounded by an insulating material.

[0011] In some embodiments, the packaging structure further includes: a third die located below the second die; a third heat dissipation structure located on the surface of the third die; wherein the heat dissipation path also contacts the surface of the third heat dissipation structure.

[0012] In some embodiments, the first heat dissipation structure has a first portion extending beyond the first die in the width direction, and a heat dissipation path connects the upper surface of the third heat dissipation structure to the lower surface of the first portion.

[0013] In some embodiments, there are multiple first dies, and a first heat dissipation structure covers the surface of each first die; there are multiple second dies, and a second heat dissipation structure covers the surface of each second die; wherein the heat dissipation structure is located between two adjacent first dies and second dies.

[0014] Embodiments of the present invention also provide a method for forming a package structure, comprising: forming a first die and a first heat dissipation structure disposed on the surface of the first die above a carrier; forming a second die and a first heat dissipation path above the first heat dissipation structure; and forming a second heat dissipation structure above the second die and the first heat dissipation path.

[0015] In some embodiments, at least two metallic materials form a first heat dissipation path.

[0016] In some embodiments, forming a first heat dissipation path above the first heat dissipation structure includes: forming a conductive pillar above the first heat dissipation structure; and forming a solder layer above the conductive pillar.

[0017] In some embodiments, before forming the first die, the method further includes: forming a third die above the carrier; forming a third heat dissipation structure above the third die; wherein, when forming the first die and the first heat dissipation structure, a second heat dissipation path is also formed connecting the third heat dissipation structure to the first heat dissipation structure.

[0018] In some embodiments, the method further includes: after forming the third heat dissipation structure, forming an insulating layer covering the third die and the third heat dissipation structure, and forming the lower part of the second heat dissipation path within the insulating layer; after forming the second heat dissipation structure, forming another insulating layer surrounding the upper part of the second heat dissipation path.

[0019] In some embodiments, the heat dissipation path extends from the upper surface of the third heat dissipation structure to the lower surface of the portion of the first heat dissipation structure that extends beyond the first die in width.

[0020] In some embodiments, the first heat dissipation path is an electrically floating connection.

[0021] In some embodiments, the first heat dissipation structure and the second heat dissipation structure are formed to have different widths.

[0022] In some embodiments, the width of the second heat dissipation structure is formed to be greater than the width of the second die. Attached Figure Description

[0023] The various aspects of the invention will be best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that, according to standard industrial practice, the components are not drawn to scale. In fact, the dimensions of the components may be arbitrarily increased or decreased for clarity of discussion.

[0024] Figure 1 This is a schematic diagram of an existing 3D packaging structure.

[0025] Figure 2 This is a schematic diagram of the packaging structure according to an embodiment of the present invention.

[0026] Figures 3A to 3M This is a schematic diagram of the various stages of a method for forming an encapsulation structure according to an embodiment of the present invention. Specific Implementation

[0027] The following disclosure provides numerous different embodiments or instances for implementing various features of the provided subject matter. Specific examples of elements and arrangements will be described below to simplify the invention. These are merely examples and are not intended to limit the invention. For example, in the following description, forming a first component above or on a second component can include embodiments where the first and second components are in direct contact, or embodiments where an additional component is formed between the first and second components such that the first and second components are not in direct contact. Furthermore, reference numerals and / or letters may be repeated throughout the various instances. Such repetition is for brevity and clarity only and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0028] Figure 2 This is a schematic diagram of the packaging structure according to an embodiment of the present invention. Figure 1As shown, the encapsulation structure 100 includes a first die 102 and a second die 104 located below the first die 102. A first heat dissipation structure 106 is disposed on the surface of the first die 102. A second heat dissipation structure 108 is disposed on the surface of the second die 104. The encapsulation structure 100 also includes a heat dissipation path 112, which contacts the surfaces of the first heat dissipation structure 106 and the second heat dissipation structure 108. By providing a heat dissipation path 112 that contacts both the first heat dissipation structure 106 of the first die 102 and the second heat dissipation structure 108 of the second die 104, the lower second die 104 can effectively dissipate heat, conduct the generated heat, and avoid its temperature from becoming too high, thereby achieving the purpose of heat dissipation of the inner layer of the encapsulation structure.

[0029] Continue to combine Figure 2 As shown, there are two first dies 102 and two second dies 104. The width of the first heat dissipation structure 106 used for the first die 102 and the width of the second heat dissipation structure 108 used for the second die 104 can be different. The width direction of the first heat dissipation structure 106 refers to the direction in which it extends from one first die 102 to another first die 102, and the width direction of the second heat dissipation structure 108 refers to the direction in which it extends from one second die 104 to another second die 104.

[0030] In the illustrated embodiment, the width of the second heat dissipation structure 108 is smaller than the width of the first heat dissipation structure 106. The width of the second heat dissipation structure 108 is greater than the width of each second die 104. Specifically, the first heat dissipation structure 106 extends beyond the first die 102 in width at a position between the two first dies 102, that is, the first heat dissipation structure 106 has a portion extending beyond the first die 102 in the width direction, for example, the portion located between the two first dies 102. The second heat dissipation structure 108 extends beyond the second die 104 in width at a position between the two second dies 104, that is, the second heat dissipation structure 108 has a portion extending beyond the second die 104 in the width direction, for example, the portion located between the two second dies 104. The heat dissipation path 112 connects from the lower surface of the portion of the second heat dissipation structure 108 that extends beyond the second die 104 in width to the portion of the first heat dissipation structure 106 that extends beyond the first die 102 in width, that is, the heat dissipation path 112 connects from the position between the two second dies 104 to the position between the two first dies 102.

[0031] In some embodiments, the heat dissipation path 112 includes at least two metallic materials. For example, the at least two metallic materials include a conductive pillar 116 (e.g., a copper pillar) disposed above the second heat dissipation structure 108 and a solder layer 115 (e.g., a tin layer) disposed above the conductive pillar 116. By adding high thermal conductivity materials such as copper and tin to the heat dissipation path 112, heat dissipation efficiency can be greatly improved. In addition, the heat dissipation path 112 may also include a heat sink 117 located above the solder layer 115 and a conductive material layer 114 located below the conductive pillar 116. In other embodiments, the position and structure of the heat dissipation path 112 may also be configured differently.

[0032] In some embodiments, the heat dissipation path 112 is electrically floating, meaning that the heat dissipation path 112 is not connected to electrical signals within the package structure 100. The heat dissipation path 112 may be surrounded by an insulating material. For example... Figure 2 As shown, it is surrounded by insulating material 120 surrounding the second core 104.

[0033] Furthermore, the package structure 100 also includes a third die 118 located below the second die 104. The third die 118 is the bottommost die. A third heat dissipation structure 119 is located on the surface of the third die 118; the heat dissipation path 112 also contacts the surface of the third heat dissipation structure 119. Figure 2 In this configuration, the heat dissipation path 112 connects from the upper surface of the third heat dissipation structure 119 to the lower surface of the first heat dissipation structure 106 in the middle portion between the two first dies 102. With this configuration, the heat dissipation path 112 connects the third heat dissipation structure 119 of the lowermost third die 118 to the first heat dissipation structure 106 via the second heat dissipation structure 108, enabling effective heat dissipation of the lower third die 118 and preventing it from overheating.

[0034] Similarly, the heat dissipation path 112 between the second heat dissipation structure 108 and the third heat dissipation structure 119 may include conductive pillars 116' (e.g., copper pillars) and a solder layer 115' (e.g., tin layer) disposed above the conductive pillars 116'. It may also include a heat sink 117' above the solder layer 115' and a conductive material layer 114' below the conductive pillars 116'. Insulating material 120 also surrounds the third die 118. The heat dissipation path 112 between the second heat dissipation structure 108 and the third heat dissipation structure 119 may also be surrounded by insulating material, such as... Figure 2 As shown, it is surrounded by insulating material 120 surrounding the third core 118.

[0035] Figures 3A to 3M This is a schematic diagram of various stages of a method for forming a packaging structure according to an embodiment of the present invention. Figure 3A As shown, a release layer 302 is provided above the first carrier 391, and a first dielectric layer 303 is formed on the release layer 302. Figure 3B As shown, a first redistribution line 301 is formed above the first dielectric layer 303, and a second dielectric layer 313 is formed covering the first redistribution line 301. Then, as... Figure 3C Conductive pillars 306, for example copper pillars, are formed in the second dielectric layer 313 and connected to the first redistribution line 301.

[0036] Next, as Figure 3D As shown, a first die 318 is attached to the conductive post 306. This first die 318 is the bottommost die (third die) in the package structure. A solder layer 305 is formed on the surface of the first die 318, and a first heat dissipation structure 319 (e.g., a heat sink) is connected above the first die 318 through the solder layer 305, as shown. Figure 3E Furthermore, a third dielectric layer 323 is formed that covers the first die 318 and the first heat dissipation structure 319.

[0037] exist Figure 3F For example, an opening 392 is formed through a laser engraving process, passing through the third dielectric layer 323 to reach the surface of the first heat dissipation structure 319 and the first redistribution line 301. The opening 392 is filled with conductive material to form a via, and a line connecting to the via is formed above the third dielectric layer 323. The via and the line can be referred to as the second redistribution line 311.

[0038] exist Figure 3G In this configuration, a fourth dielectric layer 333 and conductive posts 316 located within the fourth dielectric layer 333 are formed on the second redistribution line 311. A second die 314 is attached to the conductive posts 316 connected to the second redistribution line 311. The conductive posts 316 connected to the first heat dissipation structure 319 form heat dissipation paths. A solder layer 315 and a second heat dissipation structure 317, such as a heat sink, are formed on the conductive posts 316 connected to the first heat dissipation structure 319. Figure 3H In this configuration, a solder layer 325 and a third heat dissipation structure 308 are formed on the second die 314 and the second heat dissipation structure 317. The components connecting the first heat dissipation structure 319 and the third heat dissipation structure 308 can be collectively referred to as the first heat dissipation path.

[0039] exist Figure 3I In this process, a fifth dielectric layer 343 is formed, covering the second die 314 and the third heat dissipation structure 308. A via is formed, connecting a line through the fifth dielectric layer 343 to the second redistribution line 311, and a line located on the fifth dielectric layer 343 connected to the via is also formed. The via and the line can be referred to as the third redistribution line 321. Furthermore, a sixth dielectric layer 353 and conductive pillars 326 located within the sixth dielectric layer 353 are formed above the third redistribution line 321.

[0040] Then, refer to Figure 3J A second carrier 393 is attached above the sixth dielectric layer 353. The resulting structure is then inverted, and the first carrier 391 is removed using a release layer. Solder balls 394 connected to the first redistribution line are formed. (Reference) Figure 3K The solder ball 394 is attached to the third carrier 395, the resulting structure is inverted and the second carrier 393 is removed.

[0041] exist Figure 3L In this configuration, a third die 312 is attached to the sixth dielectric layer 353 via conductive posts 316 above the second die 314. A solder layer 325 and a fourth heat dissipation structure 327 are formed on the conductive posts 326 between the third dies 312. A solder layer 335 and a fifth heat dissipation structure 336 are formed above the third die 312 and the fourth heat dissipation structure 327. The components connecting the third heat dissipation structure 308 and the fifth heat dissipation structure 336 can be collectively referred to as the second heat dissipation path. The first heat dissipation path and the second heat dissipation path can be collectively referred to as the heat dissipation path.

[0042] exist Figure 3M In the process, the third carrier 395 is removed and connected to the substrate 400 via solder balls 394 to form a semiconductor package structure.

[0043] By connecting the first heat dissipation structure 319 of the bottom first-layer die 318 to the fifth heat dissipation structure 336 of the third-layer die 312 via a heat dissipation path, the bottom first-layer die 318 can be effectively cooled, preventing it from overheating.

[0044] The foregoing summary outlines features of several embodiments that enable those skilled in the art to better understand various aspects of this disclosure. Those skilled in the art should understand that other processes and structures can be readily designed or modified based on this invention to achieve the same objectives and / or benefits as the embodiments described herein. Those skilled in the art should also recognize that these equivalent structures do not depart from the spirit and scope of the invention, and that various changes, substitutions, and modifications can be made without departing from the spirit and scope of the invention.

Claims

1. A packaging structure, characterized in that, include: First die; A first heat dissipation structure is disposed on the surfaces of two adjacent first dies and has a first portion located between the two adjacent first dies. Second die; Located below the first die; The second heat dissipation structure is disposed on the surfaces of two adjacent second dies and has a second portion located between the two adjacent second dies; The third die is located below the two adjacent second dies and has an upper surface facing the first portion; The third heat dissipation structure is located on the upper surface of the third die; The heat dissipation path is located in the interlayer space between the first part and the second part, and is in contact with the surfaces of the first heat dissipation structure and the second heat dissipation structure. The heat dissipation path is also located in the interlayer space between the second part and the third heat dissipation structure on the upper surface of the third die, and contacts the upper surface of the third heat dissipation structure. The heat dissipation path is electrically floating and includes a conductive post above the third heat dissipation structure and a solder layer disposed above the conductive post.

2. The packaging structure according to claim 1, characterized in that, The width of the second heat dissipation structure is smaller than the width of the first heat dissipation structure.

3. The packaging structure according to claim 2, characterized in that, The heat dissipation path connects the lower surface of the first part to the second part.

4. The packaging structure according to claim 1, characterized in that, The heat dissipation path includes a conductive pillar disposed above the second heat dissipation structure and a solder layer disposed above the conductive pillar.

5. The packaging structure according to claim 1, characterized in that, The heat dissipation path is surrounded by insulating material.

6. The packaging structure according to claim 1, characterized in that, The heat dissipation path connects the upper surface of the third heat dissipation structure to the lower surface of the first part.

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