Packaging structure and forming method thereof

Abstract

An embodiment of the present invention relates to a packaging structure and a method for forming the same. The packaging structure includes: a first packaging component including a first conductive pad, and a second packaging component covering the first packaging component. The second packaging component includes a surface dielectric layer, and a conductive bump protruding below the surface dielectric layer. The first conductive bump includes a first side wall facing away from the center of the first packaging component, and a second side wall facing the center. A solder bump joins the first conductive pad to the first conductive bump. The solder bump contacts the first side wall. An underfill is between the first packaging component and the second packaging component, and the underfill contacts the second side wall.

Description

Technical Field

[0001] Embodiments of the present invention relate to a packaging structure and a method for forming the same. Background Art

[0002] Integrated circuit packages may include multiple package components bonded together. In a recent development in applications, high performance computing (HPC) packages have been manufactured that typically include very large package substrates and plug-ins. The package substrate and plug-in may include multiple layers. This, combined with the significant structural and material differences between the package substrate and the plug-in and their large size, results in significant differences in thermal expansion between the package substrate and the overlying package components. Problems such as cold bonding and bridging may result. Summary of the invention

[0003] According to one aspect of an embodiment of the present invention, a method for forming a package structure is provided, comprising: determining positions of a first electrical connector of a first package component and a second electrical connector of a second package component, wherein the first electrical connector and the second electrical connector having the same position are an electrical connector pair; determining an expected misalignment value of the first electrical connector and the second electrical connector in response to a reflow process for joining the first package component to the second package component; calculating a pre-offset value for each electrical connector pair based on the expected misalignment value; modifying the positions of the first electrical connector and the second electrical connector to generate a modified design, wherein the positions of the first electrical connector and the second electrical connector in the same electrical connector pair are offset from each other by the pre-offset value; manufacturing the first package component and the second package component, wherein the first electrical connector and the second electrical connector have the modified design; and

[0004] A reflow process is performed to bond the first package component to the second package component.

[0005] According to another aspect of an embodiment of the present invention, a packaging structure is provided, including: a first packaging component, including a first electrical connector; a second packaging component, including a second electrical connector; a first solder bump, joining the first electrical connector with the second electrical connector, wherein a first center of the first electrical connector is misaligned with a second center of the second electrical connector by a first post-reflow misalignment value; a third electrical connector, in the first packaging component; a fourth electrical connector, in the second packaging component, wherein the third electrical connector and the fourth electrical connector are closer to an additional center of the first packaging component than the first electrical connector and the second electrical connector, and a third center of the third electrical connector is misaligned with a fourth center of the fourth electrical connector by a second post-reflow misalignment value, the second post-reflow misalignment value being less than the first post-reflow misalignment value; and a second solder bump, joining the third electrical connector with the fourth electrical connector.

[0006] According to another aspect of an embodiment of the present invention, a packaging structure is provided, comprising: a first packaging component, comprising a first conductive pad; a second packaging component, overlying the first packaging component, the second packaging component comprising: a surface dielectric layer; a first conductive bump, protruding below the surface dielectric layer, wherein the first conductive bump comprises a first side wall away from the center of the first packaging component and a second side wall facing the center; a solder bump, joining the first conductive pad to the first conductive bump, wherein the solder bump contacts the first side wall; and a bottom filler, between the first packaging component and the second packaging component, wherein the bottom filler contacts the second side wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] 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 emphasized that, in accordance with standard practice in the industry, the various components are not drawn to scale. In fact, for clarity of discussion, the size of the various components may be arbitrarily increased or reduced.

[0008] Figure 1 A first design of a first packaged component and a second packaged component to be bonded together is shown in accordance with some embodiments.

[0009] Figure 2A and Figure 2B An expected misalignment of an electrical connector in a first package component with an electrical connector in a second package component in response to a reflow process is shown in accordance with some embodiments.

[0010] Figure 3A and Figure 3B A cross-sectional view and a plan view, respectively, illustrate pre-biased electrical connectors in first and second packaged components according to some embodiments.

[0011] Figure 4A and Figure 4B Cross-sectional and plan views, respectively, illustrate misalignment of electrical connectors in first and second packaged components after a reflow process in accordance with some embodiments.

[0012] Figure 5 An example of a heterogeneous package is shown in accordance with some embodiments.

[0013] Figure 6 A top view of an electrical connector pair and solder on outer sidewalls of the electrical connectors is shown in accordance with some embodiments.

[0014] Figure 7 A process flow for designing and forming a package according to some embodiments is shown. DETAILED DESCRIPTION

[0015] 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 disclosure. Of course, these are merely examples and are not intended to be restrictive. For example, in the following description, forming a first component above or on a second component may include an embodiment in which the first component and the second component are directly contacted, and may also include an embodiment in which an additional component may be formed between the first component and the second component so that the first component and the second component may not be in direct contact. In addition, the present disclosure may repeat reference numerals and / or characters in various examples. This repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or configurations discussed.

[0016] Furthermore, for ease of description, spatially relative terms such as "under", "beneath", "lower", "over", "upper", etc. may be used herein to describe the relationship of one element or component to another (or additional) elements or components as shown in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0017] According to some embodiments, a package and a method for forming the package are provided with an electrical connector having misalignment between the electrical connectors to be joined. In an example process for forming a package, the expected misalignment value between the first electrical connector in the first package component and the second electrical connector in the second package component is first determined. A portion of the misalignment value is assigned as a pre-offset value, and the design of the first and / or second package components is modified so that the first electrical connector is pre-offset relative to the corresponding second electrical connector. "Pre-offset" is so named because it is before the reflow for joining the first and second package components together. Since the pre-offset value is less than the corresponding expected misalignment value, after the reflow process, the first electrical connector of the first package component and the corresponding second electrical connector in the second package component are still misaligned, which may help reduce the strain in the solder area. For any first and second electrical connectors to be connected, the distance between the first electrical connector and the center of the tube core should be greater than the distance between the second electrical connector and the center of the tube core. Thus, the solder covers a portion of one side of the first electrical connector in the bump deformation structure to reduce strain. The present disclosure ensures better chip-package interaction (CPI) reliability performance than without deformed bumps because the larger solder volume on the high strain side can effectively reduce the strain to prevent bump cracking.

[0018] The embodiments discussed herein will provide examples that enable making or using the subject matter of the present disclosure, and those of ordinary skill in the art will readily appreciate the modifications that may be made while remaining within the intended scope of the different embodiments. Throughout the different views and illustrative embodiments, the same reference numerals are used to refer to the same elements. Although method embodiments may be discussed as being performed in a particular order, other method embodiments may be performed in any logical order.

[0019] Figure 1 , Figure 2A , Figure 2B , Figure 3A , Figure 3B , Figure 4A and Figure 4B sectional views and plan views of intermediate stages in the design and formation of a package according to some embodiments of the present disclosure are shown. The corresponding processes are also schematically reflected in FIG. Figure 7 In the process flow 400 shown.

[0020] Figure 1 A cross-sectional view of a package component according to some embodiments is shown. The package component includes package components 100 and 200, which are joined together by solder bonding. It should be understood that package components 100 and 200 can be physical components that have been manufactured, or can be designs of these package components that have not yet been manufactured. According to some embodiments of the present disclosure, package components 100 and 200 will be joined to form a high-performance computing (HPC) package, which can be used for applications with high performance requirements such as artificial intelligence (AI) applications.

[0021] According to some embodiments, the package component 100 is or includes a package substrate, which may be a core package substrate or a coreless package substrate. The package component 100 may also be or include a printed circuit board, a package, etc. When it is or includes a core package substrate, the package component 100 includes a core 102, which includes a core dielectric 104, a conductive tube 106 penetrating the core dielectric 104, and a dielectric filling material 108 inside the conductive tube 106. According to some embodiments, the core dielectric 104 is formed by one or more materials selected from the group consisting of: epoxy resin, resin, glass fiber, prepreg (which includes epoxy resin, resin and / or glass fiber), glass, molding compound, plastic, a combination thereof, and a multilayer thereof. The dielectric layer 111 may be formed by or include a polymer, a prepreg, a glass fiber, etc. The RDL 110 is formed in the dielectric layer 111 and is electrically interconnected by the conductive tube 106. According to some embodiments, RDL 110 is formed of or includes copper, aluminum, titanium, nickel, gold, or the like, alloys thereof, or multiple layers thereof.

[0022] An electrical connector 112 is formed on the top surface of the package component 100. According to some embodiments, the electrical connector 112 is a bonding pad. When the electrical connector 112 is a bonding pad, the dielectric layer 114 may be formed to cover the edge portion of the electrical connector 112. The central portion of the electrical connector 112 is exposed through an opening in the dielectric layer 114. According to an alternative embodiment, the electrical connector 112 includes a metal bump protruding above the top surface of the dielectric layer 114. The metal bump may be formed of copper and may or may not include a layer formed of other metals or metal alloys including nickel, palladium, etc. (multiple). The dielectric layer 114 may be formed of a solder mask or a polymer such as polybenzoxazole (PBO), polyimide, benzocyclobutene (BCB), etc. According to some embodiments, a solder region (hereinafter also referred to as a solder bump) 116 is preformed to be combined with the electrical connector 112. The solder region 116 is therefore referred to as a pre-solder region 116 hereinafter.

[0023] According to some embodiments, electrical connector 120 is formed on the bottom side of package component 100 and electrically connected to electrical connector 112 through conductive tube 106 and RDL 110. Dielectric layer 122 may mask edge portions of electrical connector 120. Solder region 124 is formed to be combined with electrical connector 120.

[0024] According to an alternative embodiment, the package component 100 is a coreless package component that has no core and includes a plurality of redistribution lines (similar to the RDL 110 ) formed in a plurality of dielectric layers.

[0025] A package component 200 to be bonded to the package component 100 is also formed. According to some embodiments, the package component 200 is or includes a plug-in, which may be a semiconductor plug-in, an organic plug-in, or the like. When including a semiconductor plug-in, the plug-in may include a semiconductor substrate such as a silicon substrate and a through hole (sometimes referred to as a through silicon via) penetrating the semiconductor substrate. Dielectric layers, metal lines, and through holes are formed on opposite sides of the semiconductor substrate and are interconnected through the through holes. The dielectric layer may be formed of or include a low-k dielectric layer, silicon oxide, silicon nitride, silicon oxynitride, or the like. When it is an organic plug-in, such as Figure 1 The package component 200 schematically shown in FIG. 2 may include a plurality of dielectric layers 202 and redistribution lines 204 in the dielectric layers 202. In accordance with some embodiments, the dielectric layers 202 are formed of an organic material such as polyimide, PBO, BCB, or the like.

[0026] According to some embodiments, package component 200 includes an electrical connector 214, which may include an under bump metallization layer (UBM) 212 and a conductive bump 210. UBM 212 may include an adhesive layer, such as a titanium layer, a copper layer, or a composite layer including a copper layer on a titanium layer. Conductive bump 210 may be formed of copper, nickel, palladium, gold, combinations thereof, and multiple layers thereof. Solder region 216 may be formed on electrical connector 214. According to some embodiments, solder region 216 may not extend on the sidewalls of electrical connector 214.

[0027] According to some embodiments, the package component (s) 300 is bonded to the package component 200 through the solder region 224. The package component 300 may include one or more packages formed by a packaging process, and the package (s) may include a logic die (such as a computing die), a memory die (such as a dynamic random access memory (DRAM) die or a static random access memory (SRAM) die), a photonic die, a package (including a device die that has been packaged), an input-output (IO) die, a digital die, an analog die, a surface mount passive device, etc. The die (s) in the package component 300 may be sealed in one or more sealants, such as a molding compound, an underfill, an epoxy resin, a resin, etc. According to some embodiments of the present disclosure, the package component 300 includes a system-on-chip (SoC) die, which is a package including a device die that is bonded together to form a system. The package component 300 may also include a high bandwidth memory (HBM) stack, wherein each HBM stack includes a plurality of memory dies stacked together to form a memory stack. The memory die may be a DRAM die, an SRAM die, or another type of memory die.

[0028] According to some embodiments, one of the electrical connectors 214 is aligned with the center C100 of the package component 100, and the electrical connector 214 is referred to as the center electrical connector 214 hereinafter. The center of the package component 200 may be vertically aligned or may be offset from the center C100. There may be a package component 300 having a solder area 224 electrically coupled to the electrical connector 214. According to alternative embodiments, there is no electrical connector 214 and / or package component 300 aligned with the center C100. Therefore, the package component 300 aligned with the center C100 is shown as a dotted line to indicate that it may or may not exist.

[0029] According to some embodiments, in the initial design of the package components 100 and 200, the position of the electrical connector 214 is designed to align with the corresponding electrical connector 112 in a one-to-one correspondence. Throughout the specification, each electrical connector 112 and its corresponding electrical connector 214 are intended to be joined together and are collectively referred to as electrical connector pairs 112 / 214. Therefore, the package components 100 and 200 have multiple electrical connector pairs. Throughout the specification, when referring to electrical connectors, the terms "corresponding" and "corresponding" refer to electrical connectors that form the electrical connector 112 / 214 pair and are intended to be joined together. In other words, the electrical connectors 112 and 214 in the same electrical pair are "corresponding" electrical connectors. In addition, the centers of the electrical connectors 112 and 214 in the same electrical connector pair are referred to as "corresponding" centers hereinafter. In the initial design, the center 213 of the electrical connector 214 is vertically aligned with the center 113 of the corresponding electrical connector 112 in a one-to-one correspondence. In the specification, the term "corresponding" may be used interchangeably with the term "respective".

[0030] By arranging the packaged components 100 and 200, first, for example, by recording their X and Y coordinates (eg, Figure 2B The corresponding process is as shown in FIG. Figure 7 The process flow 400 is shown as process 402 .

[0031] Figure 2A FIG. 2 shows the package component 200 being joined to the package component 100 by a reflow process, wherein the solder regions 116 and 216 ( Figure 1) is melted to generate solder area 16. This forms package 10. According to some embodiments, the coefficient of thermal expansion (CTE) CTE100 of package component 100 is greater than the total CTECTE200 of package component 200 and the CTE300 of package component 300. For example, package component 100 as a whole can have a CTE in a range between about 12ppm / K and about 20ppm / K, and the total CTECTE200 of package component 200 and the total CTECTE300 of component 300 are in a range between about 3ppm / K and about 10ppm / K. It should be understood that in the example embodiment shown, it is assumed that CTE100 is greater than CTE200 as an example, while in other embodiments, CTE100 can also be less than CTE200, and the teachings of the present disclosure still apply. During the reflow process, both package components 100 and 200 expand, and electrical connectors 112 and 214 are laterally farther away from the center C100 of package component 100 than before the reflow process. Since CTE CTE100 is greater than CTE CTE200 in the exemplary embodiment, package component 100 expands more than package component 200. The center 113 of electrical connector 112 is thereby offset outwardly (away from center C100) from the corresponding center 213 by a misalignment value ΔS (which includes ΔS1, ΔS2, etc.). It should be understood that the misalignment value ΔS is related to the position of the corresponding electrical connectors 112 and 214, and the farther the electrical connector 112 / 214 is from the center C100, the greater the misalignment value ΔS. For example, in Figure 2A When the center electrical connector pair 112 / 214 is present at the center C100 , it is expected that the centers 113 and 213 of the center electrical connector pair 112 / 214 are not misaligned.

[0032] The misalignment value ΔS of each electrical connector pair 112 / 214 is determined. The corresponding process is shown as follows Figure 7 Process 404 in process flow 400 is shown. Each misalignment value ΔS includes a component in the X direction ( Figure 2B) and components in the Y direction. Some misalignment values ​​ΔS may have the same magnitude, and when the directions (+X, -X, +Y, and -Y) are considered, all misalignment values ​​are different from each other because misalignment values ​​with the same magnitude have different directions. According to some embodiments, package components 100 and 200 are manufactured as physical package components, and therefore an actual reflow process is performed, and the misalignment value ΔS is determined by measuring the already manufactured package 10. According to alternative embodiments, package components 100 and 200 are designs and have not been manufactured. Therefore, the package 10 is simulated, and the misalignment value ΔS of the electrical connector pair 112 / 214 is determined by simulation. For example, the material, structure, and size of the package components 100 and 200 are used as input parameters for the simulation. Moreover, the size and position of the electrical connector pair 112 / 214 (such as their distance from the center C100) are also used in the simulation to determine the misalignment value ΔS. According to some embodiments, package 10 includes package component 300, and misalignment value ΔS is also affected by the CTE of package component 300. According to alternative embodiments, package 10 includes package component 200 and does not include package component 300. Therefore, misalignment value ΔS is not affected by the CTE of package component 300.

[0033] Figure 2B It shows that Figure 2A For the purpose of distinction, the top view of the package 10 is shown in FIG. Figure 2B In the following figures, the electrical connector 112 is shown as having a hexagonal top view shape as an example, and the electrical connector 214 is shown as having a circular top view shape as an example, while the electrical connectors 112 and 214 can have any other top view shape, including but not limited to, circular, hexagonal, rectangular, elliptical, octagonal, etc. According to some embodiments, the package components 100 and 200 are substantially homogeneous, which means that the components on different parts of the package have similar characteristics, such as CTE. Therefore, the electrical connector 112 is offset from the respective engaging electrical connector 214 in a direction away from the center C100. In other words, for any electrical connector pair 112 / 214, after reflow, the corresponding centers 213 and 113 can be aligned with a straight line extending from the center C100 toward the centers 213 and 113, and the center 113 is farther away from the center C100 than the corresponding center 213. Therefore, the offset of the center 113 from the corresponding center 113 will be a radius pattern, with the center C100 as the center of the radius pattern.

[0034] In addition, the misalignment value ΔS of the electrical connector pair 112 / 214 can be proportional to the value of their distance from the center C100. Figure 2BIn the example, the ratio ΔS2 / S2 is equal to the ratio ΔS1 / S1, and is equal to the ratios ΔS3 / S3 and ΔS4 / S4. According to some embodiments, the misalignment value of the electrical connector pair 112 / 214 may be determined using the following equation 1:

[0035] ΔS = S*(CTE100–CTE200)*TempR [Equation 1]

[0036] Where S is the distance of the electrical connector pair 112 / 214 from the center C100, and ΔS is the misalignment value of the electrical connector pair 112 / 214 after reflow. The value TempR (having the unit "K") is an index that can be related to the temperature at which the solder region 16 begins to solidify after it has reflowed.

[0037] Based on the determined misalignment value ΔS of the electrical connector pair 112 / 214 , either or both of the packaged components 100 and 200 are redesigned, and the positions of the electrical connectors 112 and / or 214 are modified. Figure 3A 1 shows a cross-sectional view of the redesigned package components 100 and 200. For example, the positions of the electrical connectors 112 and 214 in the same electrical connector pair are offset relative to each other by a pre-offset value pre-S (including pre-S1, pre-S2, etc.). Each pre-offset value pre-S also has components in the X direction (+X and -X directions) and the Y direction (+Y and -Y directions), as shown in FIG. Figure 3B The term “pre-skew” means that the skew exists and is generated before the reflow process for bonding the package components 100 and 200 .

[0038] First, the pre-bias value pre-S of each electrical connector pair 112 / 214 is determined. The corresponding process is shown as follows Figure 7 406 in the process flow 400 shown. According to some embodiments, the packaged components 100 and 200 are substantially homogeneous. Therefore, as described above and as Figure 2B As shown, the misalignment value ΔS is proportional to the distance of the corresponding electrical connector pair 112 / 214 to the center C100. The pre-offset value pre-S is calculated as a fraction of the determined misalignment value ΔS. For example, the pre-offset value pre-S may be determined using the following equation:

[0039] pre-S = A*ΔS [Equation 2]

[0040] Wherein, the pre-offset factor A is less than 1.0 and may be in a range between about 0.5 and about 0.7. The importance of the pre-offset factor A is discussed in the subsequent paragraphs. Since the pre-offset factor A is less than 1.0, it means that the pre-offset value is less than the corresponding misalignment value ΔS. It should be understood that since the misalignment value of ΔS has components in the +X / -X and +Y / -Y directions, the pre-offset value pre-S also has components in the +X / -X and +Y / -Y directions. Thus, the offset value pre-S includes not only the magnitude of the offset, but also the direction of the offset.

[0041] According to an alternative embodiment, instead of making the pre-skew value Pre-S proportional to the misalignment value, the pre-skew value Pre-S is calculated as an allowable post-reflow misalignment value post-M ( Figure 4A and Figure 4B ) has a fixed predetermined value, which may be at a critical dimension W1 ( Figure 4B ) is in the range between about 1 / 5 and about 1 / 4 of ). Thus, the pre-offset value pre-S is determined using the following equation:

[0042] Pre-S = ΔS - (predetermined Pre-M) [Equation 3]

[0043] It should be understood that Equation 3 is applicable to the electrical connector pairs 112 / 214 whose misalignment value ΔS is equal to or greater than the predetermined value. For the electrical connector pairs 112 / 214 whose misalignment value ΔS is less than the predetermined value, the pre-skew value of the corresponding electrical connector pairs 112 / 214 can be set to zero (no pre-skew).

[0044] After the pre-skew value of each electrical connector pair 112 / 214 is determined, the package components 100 and 200 are redesigned, and the positions of the electrical connectors 112 and / or 214 are modified to achieve the pre-skew value. The corresponding process is shown as follows Figure 7 Process 408 in process flow 400 is shown. Figure 3A and 3B 1 and 2. The corresponding package components 100 and 200 with modified designs are shown in FIG. According to some embodiments, the package component 100 is redesigned and the position of the electrical connector 112 is modified so that the center 113 of the electrical connector 112 is offset toward the center C100 by a corresponding pre-offset value pre-S. Therefore, the center 113 of the electrical connector 112 is spaced apart from the corresponding center 213 of the corresponding electrical connector 214 by a pre-offset value pre-S (including pre-S1, pre-S2, etc.) in the lateral direction.

[0045] According to an alternative embodiment, the package component 200 is redesigned so that the center 213 of the electrical connector 214 is offset away from the center C100 by a pre-offset value pre-S (including pre-S1, pre-S2, etc.). Therefore, the center 213 of the electrical connector 214 is also spaced apart from the center 113 of the corresponding electrical connector 112 in the lateral direction by a pre-offset value pre-S1, pre-S2, etc. According to yet another alternative embodiment, both the package components 100 and 200 are redesigned to achieve pre-offset values ​​pre-SΔS1, ΔS2, etc. It should be understood that in Figure 3A In the illustrated structure, the package component 200 is merely placed on the package component 100 and has not yet been bonded to the package component 100 through a reflow process.

[0046] Figure 3B A plan view (e.g., top view) of redesigned package components 100 and 200 according to some embodiments and the positions of electrical connectors 112 and 214 is shown. Assuming that the center C100 of package component 100 is aligned (overlapped) with the center of package component 200, the center 113 of the electrical connector is pre-offset toward the center C100 relative to the center 213 of the corresponding electrical connector 214.

[0047] According to some embodiments, all electrical connector pairs 112 / 214 in package components 100 and 200 are pre-biased. However, if there is an electrical connector pair 112 / 214 exactly at the center C100, the central electrical connector pair 112 / 214 is not pre-biased. According to an alternative embodiment, the package component 100 has a central area 130 including the center C100. The central area 130 may also be symmetrical with respect to the center C100. For example, the central area 130 may be a rectangular area whose width and length are less than about 25% (or about 20%) of the corresponding width and length of the package component 100. The central area 130 may also be a circular area centered on C100, and its diameter is less than about 25% (or about 20%) of the larger of the width and length of the package component 100. According to some embodiments, all electrical connector pairs 112 / 214 inside the central area 130 are not pre-biased, while all electrical connector pairs 112 / 214 outside the central area 130 are pre-biased. The reason for not pre-shifting the electrical connector pairs in the central region 130 is that the misalignment value ΔS in the central region 130 is too small to cause problems such as cold joints and bridging. On the other hand, not pre-shifting the electrical connector pairs 112 / 214 in the central region 130 can advantageously result in the corresponding solder regions having larger post-shift values ​​(as will be discussed in subsequent paragraphs), and thus the solder regions 16 have a greater chance of climbing up the outer sidewalls of the electrical connectors 214.

[0048] like Figure 3Aand Figure 3B The redesigned packaged components shown in are then manufactured as physical and tangible components. The corresponding process is shown as Figure 7 Next, the manufactured package components 100 and 200 are bonded to each other through a reflow process. The corresponding process is shown as follows. Figure 7 The process 412 in the process flow 400 is shown. Figure 4A and Figure 4B The resulting package 10 ′ is shown in FIG. Figure 4A and Figure 4B The cross-sectional view and the top view are shown respectively. The reflow temperature and each solder area 216 and 116 ( Figure 3A ), and the reflow temperature may be in a range between about 220° C. and about 255° C. After the reflow process, the temperature of the package 10 ′ is reduced, and the resulting solder region 16 including the molten solder regions 216 and 116 is solidified. Figure 4A and 4B The structure is shown after curing, for example, when the package 10 ′ is at room temperature (eg, between about 19° C. and about 23° C.).

[0049] Since the pre-skew factor A in equation 2 is less than 1.0, this means that the pre-skew value pre-S ( Figure 2A and Figure 2B ) is less than and therefore insufficient to compensate for the misalignment value ΔS ( Figure 3A and Figure 3B ). Therefore, if Figure 4A As shown, after the reflow process, the center 113 is misaligned with the corresponding center 213. In addition, the center 113 is offset beyond the corresponding center 213 and is offset to the outside of the corresponding center 213 (to the side away from the center C100). In other words, the center 113 is farther away from the center C100 than the corresponding center 213. Throughout the specification, the misalignment value between the centers 113 and 213 in the same electrical connector pair 112 / 214 is referred to as a post-reflow misalignment value, which is indicated as post-M (identified as post-M1, post-M2, etc., respectively). In addition, each post-reflow misalignment value post-M has a component in the +X or -X direction and a component in the +Y or -Y direction ( Figure 4B ).like Figure 4A As shown, the post-reflow misalignment values ​​post-M of different electrical connector pairs 112 / 214 may be different from each other. For example, the post-reflow misalignment value post-M is greater than the post-reflow misalignment value post-M1.

[0050] Since the center 113 is on the outside of the corresponding center 213, the solder area 16 can climb on the outer side wall (the side wall facing away from the center C100) of the electrical connector 214. On the other hand, the solder area 16 will not climb on the inner side wall (the side wall facing the center C100) of the electrical connector 214. Figure 4B In the top view shown, the outer sidewalls and the corresponding inner sidewalls are opposite to each other and aligned with the straight line connecting the center C100 with the corresponding electrical connector pair 112 / 214. Forming the solder area on the outer sidewalls of the electrical connector 214 but not on the inner sidewalls has the advantageous feature of reducing the strain on the solder area 16 and the electrical connectors 112 and 214. The reason is that the outer side of the electrical connector 214 has a higher strain value than the corresponding inner side, and increasing the solder volume on the outer side can reduce the higher strain and can help protect the solder area 16 and the electrical connectors 112 and 214 from cracking, peeling, etc.

[0051] After the reflow process, underfill 18 is filled between package components 100 and 200. The underfill contacts the inner sidewall of electrical connector 214 and is separated from the outer sidewall of electrical connector 214 by solder region 16. In addition, underfill 20 may be dispensed between package components 200 and 300.

[0052] Figure 6 FIG. 1 shows a top view of an electrical connector pair 112 / 214 according to some embodiments. Figure 6 The solder area 16 is shown at the same level as the electrical connector 214 (at Figure 4A Observe the level in the part, and Figure 6 The portion of the solder area vertically between the electrical connector 214 and the underlying electrical connector 112 is not shown. Figure 4A ). Figure 6 The solder area 16 is shown on the outer side wall of the electrical connector 214 facing away from the center C100 , while the inner side wall of the electrical connector 214 facing the center C100 has no solder area 16 .

[0053] Figure 4B It shows that Figure 4A 10 ′ is a plan view (e.g., top view) of the package 10 ′ shown in . According to some embodiments, the center 113 is offset away from the center C100 relative to its corresponding center 213. The post-reflow misalignment has a radius pattern, which means that the center 113 and 213 of each electrical connector pair 112 / 214 can be aligned with a straight line connecting the center C100 to the electrical connector pair.

[0054] like Figure 4BAs shown, both the pre-skew value pre-S and the post-reflow misalignment value post-M have a component in the X direction and a component in the Y direction, and the component in the X direction and the component in the Y direction are combined to form the corresponding pre-skew value pre-S and post-reflow misalignment value post-M.

[0055] As mentioned above and Figure 2B As shown, according to some embodiments, the misalignment value ΔS is proportional to the distance S from the corresponding electrical connector pair 112 / 214 to the center C100. In addition, the pre-skew value pre-S is equal to the misalignment value ΔS multiplied by the pre-skew index A. Therefore, the post-reflow misalignment value post-M can be equal to (1-A)*ΔS, and can also be proportional to the distance S from the corresponding electrical connector pair 112 / 214 to the center C100. For example, when A is in the range between about 0.5 and 0.7, the post-reflow misalignment value post-M is equal to about 0.3 to 0.5 of the misalignment value ΔS.

[0056] According to an alternative embodiment in which the pre-skew value pre-S is calculated using Equation 3, the resulting post-reflow misalignment values ​​post-M of different electrical connector pairs 112 / 214 are identical to each other, regardless of whether they have the same or different distances from the center C100. For example, Figure 4B All electrical connector pairs 112 / 214 shown in the figure may have the same magnitude and may or may not be in the same direction, except for the electrical connector pairs 112 / 214 whose misalignment value ΔS is less than the predetermined post-M (Equation 3). For (it can be determined that the area 130 ( Figure 3B ) where) these electrical connector pairs 112 / 214, since they may not be pre-shifted, their post-reflow misalignment value post-M is equal to their misalignment value ΔS. In other words, in region 130 ( Figure 3B ), all electrical connector pairs 112 / 214 have post-M reflow misalignment values ​​that are proportional to their distances from center C100 and equal to their respective misalignment values. On the other hand, outside region 130, all electrical connector pairs 112 / 214 have the same post-reflow misalignment value that is equal to a predetermined post-M (Equation 3).

[0057] The calculation of the pre-offset value ΔS and the resulting post-reflow misalignment value post-M may also be alternatively stated as follows. According to some embodiments, as discussed in the previous paragraphs, after determining the misalignment value ΔS by experiment using a physical package or by simulation, each misalignment value ΔS is divided into two parts, one of which is the pre-offset value pre-S equal to A*ΔS. The other part is the expected post-alignment value post-M. Experimental results show that the post-alignment value post-M needs to be within a certain range. When the post-alignment value post-M is too large, there is a possibility of cold bonding (no bonding) of the solder area or bridging of the solder area to an adjacent unplanned electrical connector. When the post-alignment value post-M is too small, the effect of reducing the strain in the solder area is not sufficient. Therefore, the post-reflow misalignment value of the most corner electrical connector pair 112 / 214 is designed to be at the electrical connector 214 ( Figure 4A ) of the critical dimension (CD) (in Figure 4B 1 / 4 of the width W1). Since the most corner electrical connector pair 112 / 214 is closest to the corner of the package component 100 and is therefore subject to greater strain than any other electrical connector pair, a post-reflow misalignment value of 1 / 5 (W1) to 1 / 4 (W1) for the most corner electrical connector pair 112 / 214 can maximize benefits and minimize problems.

[0058] In the embodiments discussed above, the package 10' is substantially homogeneous, which means that the CTE values ​​of different portions of the package components 100 and 200 are close to each other, for example, varying by less than about 10% of the CTE of the individual package components 100 and 200. For example, when (multiple) package components 200 substantially cover the entire package component 100, and the materials and patterns of the package components 100 and 200 are uniform, the package 10' is homogeneous. Therefore, the pre-offset value pre-S and the post-reflow misalignment value post-M can be calculated based on the distance and CTE CTE100 and CTE200 of the electrical connector pair 112 / 214. According to other embodiments, the package 10' is heterogeneous. For example, Figure 5 A package 10' is shown in which packaged component 200 covers a portion of packaged component 100 but not all, and a substantial portion (e.g., greater than 20% or 30%) of packaged component 100 is not covered by packaged component 200. In addition, packaged component 200 is significantly offset from the center of packaged component 100. Therefore, the CTE of the portion of package 10' that includes packaged component 200 is different from the portion of package 10' that does not include packaged component 200. According to these embodiments, the formation of the package may include the following steps.

[0059] First, the position of the electrical connector pair 112 / 214 in the resulting package is determined, which corresponds to Figure 1 , except that the combined package components 100 and 200 are heterogeneous. Next, a simulation is performed using finite element modeling. In the modeling, the structure, material and reflow conditions are used as input parameters. The misalignment value ΔS (including components in the X direction and the Y direction) of each electrical connector pair 112 / 214 is determined. In these embodiments, the misalignment may not have a radiation pattern from the center C100. Next, based on the misalignment value ΔS, the pre-offset value pre-S of each electrical connector pair 112 / 214 is calculated. The calculation includes: determining the expected post-reflow misalignment value post-M, and subtracting the expected post-reflow misalignment value post-M from the simulated misalignment value ΔS to generate the pre-offset value pre-S (including components in the X direction and the Y direction) of each electrical connector pair 112 / 214. After calculating the pre-offset value pre-S, the package components 100 and / or 200 are redesigned to achieve the pre-offset value pre-S as calculated. The redesigned package components 100 and 200 may then be fabricated and bonded by reflow.

[0060] In the embodiments shown above, some processes and components are discussed according to some embodiments of the present disclosure to form a three-dimensional (3D) package. Other components and processes may also be included. For example, a test structure may be included to assist in verification testing of a 3D package or 3DIC device. The test structure may include, for example, a test pad formed in a redistribution layer or on a substrate, which allows testing of a 3D package or 3DIC, the use of a probe and / or a probe card, etc. Verification testing may be performed on intermediate structures as well as final structures. In addition, the structures and methods disclosed herein may be used in combination with a test method for intermediate verification of a known good die to increase yield and reduce cost.

[0061] In the example embodiment discussed, the CET CTE 100 of the package component 100 is greater than the CTE CTE 200 of the package component 200. It should be understood that embodiments of the present disclosure may also be applicable to cases where the CET CTE 100 of the package component 100 is less than the CTE CTE 200 of the package component 200. These processes are similar to those discussed above, except that in these embodiments the electrical connector 112 will be pre-shifted further away from the center C100 than the electrical connector 214, and the post-reflow shift of the electrical connector 112 will be further toward the center C100 than the corresponding electrical connector 214.

[0062] Embodiments of the present disclosure have some advantageous features. By determining the pre-deflection value and the post-reflow misalignment value, the strain on the solder area / bump can be reduced, and the cold joint problem and the bridging problem can also be reduced.

[0063] According to some embodiments of the present disclosure, a method includes: determining the position of a first electrical connector of a first package component and a second electrical connector of a second package component, wherein the first electrical connector and the second electrical connector having the same position are an electrical connector pair; determining a misalignment value of the first electrical connector and the second electrical connector in response to a reflow process for joining the first package component with the second package component; calculating a pre-offset value for each electrical connector pair based on the misalignment value; modifying the position of the first electrical connector and the second electrical connector to generate a modified design, wherein the positions of the first electrical connector and the second electrical connector in the same electrical connector pair are offset from each other by the pre-offset value; manufacturing the first package component and the second package component, wherein the first electrical connector and the second electrical connector have the modified design; and performing a reflow process to join the first package component with the second package component. In one embodiment, for each electrical connector pair, the corresponding pre-offset value is calculated to be less than the corresponding misalignment value. In one embodiment, after the reflow process, the first electrical connector is misaligned with the corresponding second electrical connector in the same electrical connector pair by a post-reflow misalignment value. In one embodiment, the post-reflow misalignment value is in a range greater than 1 / 5 of the width of the first electrical connector and less than 1 / 4 of the width. In one embodiment, before the reflow process, the first electrical connector is closer to the center of the first package component than the corresponding second electrical connector in the same electrical connector pair, and after the reflow process, the first electrical connector is farther away from the center of the first package component than the corresponding second electrical connector in the same electrical connector pair. In one embodiment, in the modified design, the first electrical connector is offset farther away from or toward the center of the first package component than the corresponding second electrical connector in the same electrical connector pair. In one embodiment, the first package component has a greater coefficient of thermal expansion than the second package component, and wherein the first electrical connector is offset toward the center of the first package component than the corresponding second electrical connector in the same electrical connector pair. In one embodiment, the pre-offset value is calculated as the product of the misalignment value and an exponent, and the exponent is greater than 0 and less than 1.

[0064] According to some embodiments of the present disclosure, a structure includes: a first package component including a first electrical connector; a second package component including a second electrical connector; a first solder bump that joins the first electrical connector with the second electrical connector, wherein a first center of the first electrical connector is misaligned with a second center of the second electrical connector by a first post-reflow misalignment value; a third electrical connector in the first package component; a fourth electrical connector in the second package component, wherein the third electrical connector and the fourth electrical connector are closer to an additional center of the first package component than the first electrical connector and the second electrical connector, and a third center of the third electrical connector is misaligned with a fourth center of the fourth electrical connector by a second post-reflow misalignment value, the second post-reflow misalignment value being less than the first post-reflow misalignment value; and a second solder bump that joins the third electrical connector with the fourth electrical connector. In one embodiment, the first electrical connector protrudes beyond a surface of the first package component, and the first electrical connector includes a first sidewall facing away from the center of the first package component, wherein the first solder bump contacts the first sidewall; and a second sidewall facing the center of the first package component, wherein the first solder bump is spaced apart from the second sidewall. In one embodiment, the structure further includes a bottom fill between the first package component and the second package component, wherein the bottom fill contacts the second side wall of the first electrical connector. In one embodiment, the first post-reflow misalignment value is in a range between about 1 / 5 and about 1 / 4 of a critical dimension of the first electrical connector. In one embodiment, the first center is offset from the second center in a direction pointing from the additional center of the first package component to the first center. In one embodiment, the first package component has a greater coefficient of thermal expansion than the second package component, and wherein the first center is farther away from the additional center of the first package component than the second center. In one embodiment, a first ratio of the first post-reflow misalignment value to the first distance is equal to a second ratio of the second post-reflow misalignment value to the second distance, wherein the first distance is the distance between the first electrical connector and the additional center of the first package component, and the second distance is the distance between the third electrical connector and the additional center.

[0065] According to some embodiments of the present disclosure, a structure includes: a first package component including a first conductive pad; a second package component overlying the first package component, the second package component including a surface dielectric layer; a first conductive bump protruding below the surface dielectric layer, wherein the first conductive bump includes a first sidewall facing away from the center of the first package component and a second sidewall facing the center; a solder bump bonding the first conductive pad to the first conductive bump, wherein the solder bump contacts the first sidewall; and an underfill between the first package component and the second package component, wherein the underfill contacts the second sidewall. In one embodiment, a first center of the first conductive pad is farther from the center of the first package component than a second center of the first conductive bump by a first post-reflow misalignment value. In one embodiment, the structure further includes: a second conductive pad in the first package component; and a second conductive bump in the second package component, wherein the second conductive pad and the second conductive bump are closer to the center of the first package component than the first conductive pad and the first conductive bump, and a third center of the second conductive pad is misaligned with a fourth center of the second conductive bump by a second post-reflow misalignment value, the second post-reflow misalignment value being less than the first post-reflow misalignment value. In one embodiment, the first post-reflow misalignment value is in a range between about 20% and about 25% of a critical dimension of the first conductive bump. In one embodiment, a coefficient of thermal expansion of the second package component is greater than a coefficient of thermal expansion of the first package component.

[0066] According to some embodiments of the present disclosure, a method for forming a package structure includes: determining the position of a first electrical connector of a first package component and a second electrical connector of a second package component, wherein the first electrical connector and the second electrical connector having the same position are an electrical connector pair; determining an expected misalignment value of the first electrical connector and the second electrical connector in response to a reflow process for joining the first package component with the second package component; calculating a pre-offset value for each electrical connector pair based on the expected misalignment value; modifying the position of the first electrical connector and the second electrical connector to generate a modified design, wherein the positions of the first electrical connector and the second electrical connector in the same electrical connector pair are offset from each other by the pre-offset value; manufacturing the first package component and the second package component, wherein the first electrical connector and the second electrical connector have the modified design; and performing a reflow process to join the first package component with the second package component. In the above method, for each electrical connector pair, the corresponding pre-offset value is calculated to be less than the corresponding expected misalignment value. In the above method, after the reflow process, the first electrical connector is misaligned with the corresponding second electrical connector in the same electrical connector pair by the post-reflow misalignment value. In the above method, the post-reflow misalignment value is within a range greater than 1 / 5 of the width of the first electrical connector and less than 1 / 4 of the width. In the above method, before the reflow process, the first electrical connector is closer to the center of the first package component than the corresponding second electrical connector in the same electrical connector pair, and after the reflow process, the first electrical connector is further away from the center of the first package component than the corresponding second electrical connector in the same electrical connector pair. In the above method, in the modified design, the first electrical connector is offset further away from or more toward the center of the first package component than the corresponding second electrical connector in the same electrical connector pair. In the above method, the thermal expansion coefficient of the first package component is greater than that of the second package component, and wherein the first electrical connector is offset more toward the center of the first package component than the corresponding second electrical connector in the same electrical connector pair. In the above method, the pre-offset value is calculated as the product of the expected misalignment value and an exponent, and the exponent is greater than 0 and less than 1.

[0067] According to some embodiments of the present disclosure, a package structure includes: a first package component including a first electrical connector; a second package component including a second electrical connector; a first solder bump, joining the first electrical connector with the second electrical connector, wherein a first center of the first electrical connector is misaligned with a second center of the second electrical connector by a first post-reflow misalignment value; a third electrical connector in the first package component; a fourth electrical connector in the second package component, wherein the third electrical connector and the fourth electrical connector are closer to an additional center of the first package component than the first electrical connector and the second electrical connector, and a third center of the third electrical connector is misaligned with a fourth center of the fourth electrical connector by a second post-reflow misalignment value, the second post-reflow misalignment value being less than the first post-reflow misalignment value; and a second solder bump, joining the third electrical connector with the fourth electrical connector. In the above package structure, the first electrical connector protrudes beyond a surface of the first electrical connector, and the first electrical connector includes: a first sidewall, facing away from the center of the first package component, wherein the first solder bump contacts the first sidewall; and a second sidewall, facing the center of the first package component, wherein the first solder bump is spaced apart from the second sidewall. In the above-mentioned packaging structure, it also includes a bottom fill between the first packaging component and the second packaging component, wherein the bottom fill contacts the second side wall of the first electrical connector. In the above-mentioned packaging structure, the first post-reflow misalignment value is in a range between about 1 / 5 and about 1 / 4 of the critical dimension of the first electrical connector. In the above-mentioned packaging structure, the first center is offset from the second center in a direction pointing from the additional center of the first packaging component to the first center. In the above-mentioned packaging structure, the thermal expansion coefficient of the first packaging component is greater than that of the second packaging component, and wherein the first center is farther away from the additional center of the first packaging component than the second center. In the above-mentioned packaging structure, a first ratio of the first post-reflow misalignment value to the first distance is equal to a second ratio of the second post-reflow misalignment value to the second distance, wherein the first distance is the distance between the first electrical connector and the additional center of the first packaging component, and the second distance is the distance between the third electrical connector and the additional center.

[0068] According to some embodiments of the present disclosure, a packaging structure includes: a first packaging component including a first conductive pad; a second packaging component overlying the first packaging component, the second packaging component including: a surface dielectric layer; a first conductive bump protruding below the surface dielectric layer, wherein the first conductive bump includes a first sidewall facing away from the center of the first packaging component and a second sidewall facing the center; a solder bump bonding the first conductive pad to the first conductive bump, wherein the solder bump contacts the first sidewall; and an underfill between the first packaging component and the second packaging component, wherein the underfill contacts the second sidewall. In the above packaging structure, a first center of the first conductive pad is farther from the center of the first packaging component than a second center of the first conductive bump by a first post-reflow misalignment value. In the above-mentioned packaging structure, it also includes: a second conductive pad in the first packaging component; and a second conductive bump in the second packaging component, wherein the second conductive pad and the second conductive bump are closer to the center of the first packaging component than the first conductive pad and the first conductive bump, and the third center of the second conductive pad is misaligned with the fourth center of the second conductive bump by a second post-reflow misalignment value, and the second post-reflow misalignment value is less than the first post-reflow misalignment value. In the above-mentioned packaging structure, the first post-reflow misalignment value is in the range between about 20% and about 25% of the critical dimension of the first conductive bump. In the above-mentioned packaging structure, the thermal expansion coefficient of the second packaging component is greater than the thermal expansion coefficient of the first packaging component.

[0069] The features of several embodiments are summarized above so that those skilled in the art can better understand aspects of the present disclosure. Those skilled in the art will appreciate that they can easily use the present disclosure 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 will also appreciate that such equivalent constructions do not deviate from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and modifications herein without departing from the spirit and scope of the present disclosure.

Claims

1. A method for forming a packaging structure, comprising: Determining positions of a first electrical connector of a first package component and a second electrical connector of a second package component, wherein the first electrical connector and the second electrical connector having the same position are an electrical connector pair; determining an expected misalignment value of the first electrical connector and the second electrical connector in response to a reflow process for bonding the first packaged component to the second packaged component; calculating a pre-bias value for each of the electrical connector pairs based on the predicted misalignment value; modifying the positions of the first electrical connector and the second electrical connector to generate a modified design, wherein the positions of the first electrical connector and the second electrical connector in the same electrical connector pair are offset from each other by the pre-offset value; manufacturing the first package component and the second package component, wherein the first electrical connector and the second electrical connector have the modified design; and A reflow process is performed to bond the first package component to the second package component.

2. The method according to claim 1, wherein: For each of the electrical connector pairs, a corresponding pre-skew value is calculated to be less than a corresponding expected misalignment value.

3. The method according to claim 1, wherein: After a reflow process, the first electrical connector is misaligned with a corresponding second electrical connector in the same electrical connector pair by a post-reflow misalignment value.

4. The method according to claim 3, wherein: The post-reflow misalignment value is within a range greater than 1 / 5 of a width of the first electrical connector and less than 1 / 4 of the width.

5. The method according to claim 1, wherein: Before the reflow process, the first electrical connector is closer to the center of the first package component than the corresponding second electrical connector in the same electrical connector pair, and after the reflow process, the first electrical connector is farther away from the center of the first package component than the corresponding second electrical connector in the same electrical connector pair.

6. The method according to claim 1, wherein: In the modified design, the first electrical connector is offset further away from or toward a center of the first package component than a corresponding second electrical connector in the same electrical connector pair.

7. The method according to claim 6, wherein: The first packaged component has a greater coefficient of thermal expansion than the second packaged component, and wherein the first electrical connector is offset further toward a center of the first packaged component than the corresponding second electrical connector in the same electrical connector pair.

8. The method according to claim 1, wherein: The pre-offset value is calculated as the product of the expected misalignment value and an exponent, and the exponent is greater than 0 and less than 1.

9. A packaging structure, comprising: A first packaged component including a first electrical connector; a second package component including a second electrical connector; a first solder bump that joins the first electrical connector to the second electrical connector, wherein a first center of the first electrical connector is misaligned with a second center of the second electrical connector by a first post-reflow misalignment value; a third electrical connector, in the first package component; a fourth electrical connector in the second package component, wherein the third electrical connector and the fourth electrical connector are closer to a center of the first package component than the first electrical connector and the second electrical connector, and a third center of the third electrical connector is misaligned with a fourth center of the fourth electrical connector by a second post-reflow misalignment value, the second post-reflow misalignment value being less than the first post-reflow misalignment value; and a second solder bump to join the third electrical connector to the fourth electrical connector; wherein a first ratio of the first post-reflow misalignment value to a first distance is equal to a second ratio of the second post-reflow misalignment value to a second distance, wherein the first distance is the distance between the first electrical connector and the center of the first package component, and the second distance is the distance between the third electrical connector and the center.

10. The packaging structure according to claim 9, wherein: The first electrical connector protrudes beyond a surface of the first electrical connector, and the first electrical connector comprises: a first sidewall facing away from a center of the first package component, wherein the first solder bump contacts the first sidewall; and A second sidewall faces the center of the first package component, wherein the first solder bump is spaced apart from the second sidewall.

11. The package structure according to claim 10, further comprising a bottom fill between the first package component and the second package component, wherein: The bottom filler contacts the second side wall of the first electrical connector.

12. The packaging structure according to claim 9, wherein: The first post-reflow misalignment value is in a range between 1 / 5 and 1 / 4 of a critical dimension of the first electrical connector.

13. The packaging structure according to claim 9, wherein: The first center is offset from the second center in a direction directed from the center of the first package component toward the first center.

14. The packaging structure according to claim 13, wherein: The first package component has a greater coefficient of thermal expansion than the second package component, and wherein the first center is further away from the center of the first package component than the second center.

15. The packaging structure according to claim 9, wherein: The first package component is a coreless package component.

16. A packaging structure, comprising: A first package component, comprising a first conductive pad and a second conductive pad, wherein the first conductive pad is at a first distance from a center of the first package component, and the second conductive pad is at a second distance from the center; A second packaging component is disposed on the first packaging component, and the second packaging component includes Surface dielectric layer; A first conductive bump and a second conductive bump protruding below the surface dielectric layer, wherein the first conductive bump comprises a first sidewall facing away from a center of the first package component and a second sidewall facing the center; a solder bump bonding the first conductive pad to the first conductive bump, wherein the solder bump contacts the first sidewall; and A bottom fill between the first packaging component and the second packaging component, wherein the bottom fill contacts the second sidewall; Among them, the first center of the first conductive pad is farther away from the center of the first package component than the second center of the first conductive bump by a first post-reflow misalignment value, the third center of the second conductive pad is misaligned with the fourth center of the second conductive bump by a second post-reflow misalignment value, and the first ratio of the first post-reflow misalignment value to the first distance is equal to the second ratio of the second post-reflow misalignment value to the second distance.

17. The packaging structure according to claim 16, wherein: The first packaging component as a whole has a coefficient of thermal expansion in a range between 12 ppm / K and 20 ppm / K.

18. The package structure according to claim 16, wherein: The second conductive pad and the second conductive bump are closer to a center of the first package component than the first conductive pad and the first conductive bump, and the second post-reflow misalignment value is less than the first post-reflow misalignment value.

19. The package structure according to claim 16, wherein: The first post-reflow misalignment value is within a range between 20% and 25% of a critical dimension of the first conductive bump.

20. The package structure according to claim 16, wherein: The second packaging component has a thermal expansion coefficient greater than a thermal expansion coefficient of the first packaging component.

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