Packaging structure

Abstract

The utility model provides a kind of packaging structure, the packaging structure includes substrate;First bump, is set on substrate;Second bump, is set on first bump, and the width of second bump is different from the width of first bump.By setting multiple stacked lead bump structures on substrate instead of traditional wire bonding, the wire diameter of lead bump structure can be more than doubled compared to traditional lead wire, effectively avoiding the problem of line collision caused by excessively long lead wire.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging technology, and specifically to a packaging structure. Background Technology

[0002] Currently, HBPOP (High Bandwidth Package on Package) structures consist of two interconnected substrates, with signal interconnection achieved between them via solder balls or copper core balls. However, with the increasing demand for high-density signal connections, traditional solder balls or copper core balls are no longer sufficient to meet performance requirements. Therefore, the industry has turned to copper pillars as a new interconnect solution. However, the copper pillar process requires substrate manufacturers to invest in grinding and copper pillar plating equipment, leading to increased manufacturing costs and failing to meet market expectations. Subsequently, the industry attempted to use wire bonding technology for vertical wire bonding. However, due to the thinness of the wires, especially with longer leads, wire breakage issues can easily occur during molding, affecting package yield and reliability. Utility Model Content

[0003] This utility model proposes a packaging structure.

[0004] Firstly, this utility model proposes a packaging structure, including:

[0005] substrate;

[0006] A first protrusion is disposed on the substrate;

[0007] A second protrusion is disposed on the first protrusion, and the width of the second protrusion is different from the width of the first protrusion.

[0008] In some alternative implementations, the width of the second protrusion is smaller than the width of the first protrusion.

[0009] In some optional embodiments, the packaging structure further includes:

[0010] A third protrusion is disposed on the second protrusion, and the width of the third protrusion is smaller than the width of the second protrusion.

[0011] In some alternative embodiments, there is a gap between the second protrusion and the third protrusion.

[0012] In some optional embodiments, the packaging structure further includes:

[0013] A molding layer is disposed on the substrate and covers the first bump, the second bump, and the third bump.

[0014] In some alternative implementations, the sealing layer extends between the second protrusion and the third protrusion.

[0015] In some optional embodiments, the packaging structure further includes:

[0016] The chip is disposed on the substrate and located between two adjacent first bumps.

[0017] In some alternative implementations, the chip is spaced apart from two adjacent first bumps.

[0018] In some optional embodiments, the packaging structure further includes:

[0019] The fourth protrusion is disposed on the third protrusion;

[0020] A vertical line is formed and positioned on the fourth protrusion.

[0021] In some alternative embodiments, the first and second sidewalls of the first protrusion have curved structures and the first and second sidewalls are asymmetrical structures.

[0022] To address the issue in HBPOP structures where vertical wire bonding between the upper and lower substrates leads to wire breakage during molding due to the thinness of the leads, especially when the leads are long, this invention provides a packaging structure that replaces traditional wire bonding with multiple stacked wire bump structures on the substrate. The wire diameter of the wire bump structure can be more than doubled compared to traditional leads, effectively avoiding the breakage problem caused by excessively long leads. Furthermore, it eliminates the need for manufacturers to invest in grinding and copper pillar plating equipment, and increases signal density. Attached Figure Description

[0023] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0024] Figure 1 This is a schematic diagram of an existing connection structure;

[0025] Figure 2 This is a physical diagram of an existing connection structure;

[0026] Figure 3 This is a schematic diagram of the packaging structure 3a according to an embodiment of the present invention;

[0027] Figure 4 yes Figure 3 A physical image of the rectangular dashed-line area in the middle;

[0028] Figure 5 This is a schematic diagram of the packaging structure 4a according to an embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the packaging structure 5a according to an embodiment of the present invention;

[0030] Figure 7 yes Figure 6 A physical image of the rectangular dashed-line area in the middle;

[0031] Figure 8 This is a schematic diagram of the packaging structure 6a according to an embodiment of the present invention;

[0032] Figure 9 This is a schematic diagram of the packaging structure 7a according to an embodiment of the present invention;

[0033] Figure 10 This is a schematic diagram of the packaging structure 8a according to an embodiment of the present invention.

[0034] Explanation of reference numerals / symbols in the attached diagram:

[0035] 101-Substrate; 102-Lead; 103-Chip; 201-Substrate; 202-First bump; 203-Second bump; 204-Third bump; 205-Fourth bump; 206-Vertical wire bonding; 207-Gap; 208-Molding layer; 209-Chip; 210-Fifth bump; 2021-First sidewall; 2022-Second sidewall; 2023-Upper surface; 2031-Lower surface; 2081-Filling particles. Detailed Implementation

[0036] The specific embodiments of this utility model will be described below with reference to the accompanying drawings and examples. Those skilled in the art can easily understand the technical problems solved by this utility model and the resulting technical effects through the content described herein. It is understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0037] It should be readily understood that the meanings of "on," "above," and "on top of" in this utility model should be interpreted in the broadest sense, such that "on" not only means "directly on something," but also means "on something" including intermediate components or layers existing between the two.

[0038] Furthermore, for ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” may be used herein to describe the relationship of one element or component to another element or component shown in the accompanying drawings. In addition to the orientations described in the figures, spatial relative terms are also intended to cover different orientations of the device during use or operation. The device may be oriented in other ways (rotated 90° or otherwise), and the spatial relative descriptive terms used herein may be interpreted accordingly.

[0039] As used herein, the term "layer" refers to a portion of material comprising a region of a certain thickness. A layer may extend over the entirety of an underlying or upper layer structure, or may have a extent smaller than that of the underlying or upper layer structure. Furthermore, a layer may be a region of a homogeneous or heterogeneous continuous structure, with a thickness less than that of the continuous structure. For example, a layer may be located between the top and bottom surfaces of a continuous structure, or between any pair of horizontal planes therebetween. A layer may extend horizontally, vertically, and / or along a tapered surface. A substrate may be a single layer, which may include one or more layers, and / or may have one or more layers on, above, and / or below it. A single layer may include multiple layers. For example, a semiconductor layer may include one or more doped or undoped semiconductor layers, and may have the same or different materials.

[0040] As used herein, the term "substrate" refers to the material on which subsequent material layers are added. The substrate itself may be patterned. The material added on top of the substrate may be patterned or may remain unpatterned. Furthermore, the substrate may comprise a wide variety of semiconductor materials, such as silicon, silicon carbide, gallium nitride, germanium, gallium arsenide, indium phosphide, etc. Alternatively, the substrate may be made of a non-conductive material, such as glass, plastic, or sapphire wafers. Further alternatively, the substrate may have semiconductor devices or circuits formed therein.

[0041] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and to facilitate understanding and reading of the contents described in the specification. They are not intended to limit the implementation conditions of this utility model and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this utility model, should still fall within the scope of the technical content disclosed in this utility model. Furthermore, the terms such as "above," "first," "second," and "a" used in this specification are merely for clarity of description and are not intended to limit the scope of implementation of this utility model. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of implementation of this utility model.

[0042] It should also be noted that the longitudinal section corresponding to the embodiment of this utility model can be the section corresponding to the front view direction, the transverse section can be the section corresponding to the right view direction, and the horizontal section can be the section corresponding to the top view direction.

[0043] Furthermore, where there is no conflict, the embodiments and features described in these embodiments can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0044] refer to Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of an existing connection structure; Figure 2 This is a physical diagram of an existing connection structure.

[0045] like Figure 1 and Figure 2 As shown, the existing connection structure may include a substrate 101, a lead 102, and a chip 103.

[0046] The lead wire 102 and the chip 103 are disposed on the substrate 101.

[0047] Here, because the lead 102 is relatively thin, when the lead is long, the lead is prone to breakage (lead 102 breaks or deforms) during the molding process, which affects the packaging yield and reliability.

[0048] refer to Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of the packaging structure 3a according to an embodiment of the present invention; Figure 4 yes Figure 3 A physical image of the rectangular dashed area in the diagram.

[0049] like Figure 3 and Figure 4 As shown, the packaging structure 3a of this utility model may include a substrate 201, a first bump 202, and a second bump 203.

[0050] The first protrusion 202 is disposed on the substrate 201. The second protrusion 203 is disposed on the first protrusion 202, and the width of the second protrusion 203 is different from the width of the first protrusion 202.

[0051] Here, the substrate 201 may include organic and / or inorganic materials. Organic materials may include, for example, polyamide (PA), polyimide (PI), epoxy resin, poly-p-phenylene benzobisoxazole (PBO) fiber, FR-4 epoxy glass cloth laminate, PP (PrePreg, also known as prepreg or semi-cured resin, semi-cured sheet), ABF (Ajinomoto Build-up Film), etc. Inorganic materials may include, for example, silicon (Si), glass, ceramic, silicon oxide, silicon nitride, tantalum oxide, etc.

[0052] The first bump 202 and the second bump 203 can be a bump structure formed by the metal wire during the wire bonding process, or it can be called a bonding point in the wire bonding process.

[0053] Here, multiple first bumps 202 and second bumps 203 can be stacked to replace traditional wire bonding to achieve docking of substrate 201 with other substrates. The wire diameter of the first bumps 202 and second bumps 203 can be increased by more than 1 times compared to the wire, effectively avoiding the wire breakage problem caused by excessively long wires. At the same time, manufacturers do not need to invest in grinding equipment and copper pillar electroplating equipment, and the signal density is improved.

[0054] In some alternative implementations, the width of the second protrusion 203 is smaller than the width of the first protrusion 202.

[0055] In some alternative implementations, the packaging structure 3a may also include a third bump 204.

[0056] The third protrusion 204 is disposed on the second protrusion 203, and the width of the third protrusion 204 is smaller than the width of the second protrusion 203.

[0057] Similarly, the third bump 204 can be a bump structure formed by the metal wire during the wire bonding process.

[0058] Here, the width of the second protrusion 203 is set to be less than the width of the first protrusion 202, and the width of the third protrusion 204 is set to be less than the width of the second protrusion 203.

[0059] Thus, the first protrusion 202 can provide a larger contact area and mechanical support capacity. Then, the gradually decreasing second protrusion 203 and third protrusion 204 are set. On the one hand, less metal material can be used, which helps to reduce costs. On the other hand, the gradually decreasing stacked structure helps to provide a more robust mechanical connection and improve the overall reliability of the structure.

[0060] In some alternative implementations, the projection of the second protrusion 203 in the vertical direction falls within the projection range of the first protrusion 202 in the vertical direction.

[0061] That is, the second protrusion 203 is completely positioned on top of the first protrusion 202.

[0062] In some alternative embodiments, a gap 207 is provided between the second protrusion 203 and the third protrusion 204.

[0063] refer to Figure 4 Due to the manufacturing process, the second protrusion 203 and the third protrusion 204 may not be in complete contact, resulting in a gap 207.

[0064] Here, gap 207 can serve as a buffer space, which helps to alleviate thermal stress concentration.

[0065] In some alternative implementations, the packaging structure 3a further includes a molding layer 208.

[0066] A molding layer 208 is disposed on a substrate 201 and covers the first bump 202, the second bump 203 and the third bump 204.

[0067] In some alternative embodiments, the sealing layer 208 has filler particles 2081.

[0068] The molding layer 208 can be formed from various molding compounds. For example, the molding compound can be one or more of the following materials: epoxy resin, filler, catalyst, pigment, release agent, flame retardant, coupling agent, hardener, low stress absorber, adhesion promoter, ion trapping agent, etc.

[0069] Here, the sealing layer 208 can protect and stabilize the first protrusion 202, the second protrusion 203 and the third protrusion 204.

[0070] In some alternative implementations, the sealing layer 208 extends between the second protrusion 203 and the third protrusion 204.

[0071] In this way, the molding material can effectively fill the gap between the second bump 203 and the third bump 204 to enhance the mechanical strength of the packaging structure 3a, and can also provide a fixed support for the third bump 204 to prevent the third bump 204 from shifting or breaking during subsequent packaging or use.

[0072] Here, the sealing layer 208 can also extend between the first protrusion 202 and the second protrusion 203, which will not be elaborated here.

[0073] In some alternative implementations, the package structure 3a also includes a chip 209.

[0074] Chip 209 can be disposed on substrate 201 and located between two adjacent first bumps 202.

[0075] In some alternative implementations, chip 209 has a gap between it and two adjacent first bumps 202.

[0076] Thus, setting a gap between the chip 209 and the two adjacent first bumps 202 can provide space for the flow of the molding material, allowing the molding layer 208 to fill the entire packaging area more evenly. It can also form a heat dissipation channel between the chip 209 and the adjacent first bumps 202, which helps to improve the thermal management capability of the packaging structure 3a, while avoiding signal crosstalk problems caused by too close a distance.

[0077] In some alternative implementations, the spacing between two adjacent first protrusions 202 is greater than or equal to 110 μm and less than 250 μm.

[0078] Here, the spacing between two adjacent first bumps 202 is greater than or equal to 110μm and less than 250μm. However, when using solder balls or copper core balls, the minimum spacing is 250μm. It can be seen that the stacked bump layout adopted in this invention significantly reduces the spacing between bumps, thereby achieving higher wiring density and a more compact packaging structure, which is beneficial to meeting the space utilization requirements of high-integration chip packaging.

[0079] In some alternative implementations, the protrusion opening of the first protrusion 202 is greater than or equal to 55 μm.

[0080] Here, the bump opening of the first bump 202 is greater than or equal to 55μm, while when using solder balls or copper core balls, the bump opening is usually greater than or equal to 60μm. It can be seen that the bump structure adopted by this utility model can significantly reduce the bump opening size while ensuring good connection performance, thereby achieving finer wiring pitch and higher packaging density, which is conducive to meeting the dual requirements of miniaturization and high performance of advanced packaging.

[0081] Continue to refer to Figure 4In some alternative embodiments, the first sidewall 2021 and the second sidewall 2022 of the first protrusion 202 have a curved structure and the first sidewall 2021 and the second sidewall 2022 are asymmetrical structures.

[0082] Here, during the formation of the first protrusion 202, due to factors such as the offset of the pressure direction applied by the bonding tool and uneven material flow, different morphological features will be formed on its two side walls during the curing process, thus presenting an asymmetrical curved surface structure.

[0083] In some alternative embodiments, the upper surface 2023 of the first protrusion 202 has a concave structure and is directly connected to the lower surface 2031 of the second protrusion 203.

[0084] Here, after completing the first protrusion and further setting a second protrusion 203 on it, a concave structure is formed on the upper surface 2023 of the first protrusion 202. This concave structure is tightly fitted and connected to the lower surface 2031 of the second protrusion 203. In this way, not only is the mechanical bonding force of the interlayer connection enhanced, but it also helps to improve the stability of the electrical contact.

[0085] In some alternative embodiments, the encapsulation structure 3a may also include a fourth bump 205 disposed on the third bump 204.

[0086] It should be noted that the number of bumps stacked in the above packaging structure 3a is only an example. The number of bumps can be set according to the actual situation, and there is no limit here.

[0087] The above describes the packaging structure 3a of one embodiment of the present invention.

[0088] refer to Figure 5 , Figure 5 This is a schematic diagram of the packaging structure 4a according to an embodiment of the present invention. Figure 5 The package structure 4a shown is similar to Figure 3 and Figure 4 The packaging structure 3a shown differs in that:

[0089] The fourth protrusion 205 is set on the third protrusion 204, and the vertical punch line 206 is set on the fourth protrusion 205.

[0090] The same effect as package structure 3a can be achieved by setting a multi-layer stacked lead bump structure on substrate 201 to replace traditional wire bonding, effectively avoiding wire breakage problems caused by excessively long leads. At the same time, a shorter vertical bonding wire 206 is set on the fourth bump 205. Due to its low height, it will also not cause wire breakage problems.

[0091] The above describes the packaging structure 4a of one embodiment of the present invention.

[0092] refer to Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the packaging structure 5a according to an embodiment of the present invention. Figure 7 yes Figure 6 A physical image of the rectangular dashed line area in the middle. Figure 6 and Figure 7 The package structure 5a shown is similar to Figure 3 and Figure 4 The packaging structure 3a shown differs in that:

[0093] The width of the third protrusion 204 is greater than or equal to the width of the second protrusion 203 and less than or equal to the width of the first protrusion 202.

[0094] In other words, the width between each layer of protrusions does not strictly follow the trend of decreasing layer by layer, but overall it does not exceed the width of the first protrusion 202 of the bottom layer.

[0095] It can achieve the same effect as package structure 3a, and can also ensure that the upper bumps have good process tolerance during the stacking process. It also avoids connection instability or stress concentration problems caused by the upper bumps being too wide, thereby improving the mechanical strength and electrical connection reliability of package structure 5a.

[0096] The above describes the packaging structure 5a of one embodiment of the present invention.

[0097] refer to Figure 8 , Figure 8 This is a schematic diagram of the packaging structure 6a according to an embodiment of the present invention. Figure 8 The package structure 6a shown is similar to Figure 6 and Figure 7 The packaging structure 5a shown differs in that:

[0098] The fourth protrusion 205 is set on the third protrusion 204, and the vertical punch line 206 is set on the fourth protrusion 205.

[0099] The same effect can be achieved with encapsulation structures 3a, 4a, and 5a, which will not be elaborated here.

[0100] The above describes the packaging structure 6a of one embodiment of the present invention.

[0101] refer to Figure 9 , Figure 9 This is a schematic diagram of the packaging structure 7a according to an embodiment of the present invention. Figure 9 The package structure 7a shown is similar to Figure 3 and Figure 4 The packaging structure 3a shown differs in that:

[0102] The widths of the first protrusion 202, the second protrusion 203, the third protrusion 204, and the fourth protrusion 205 can be the same.

[0103] It can achieve the same effect as the encapsulation structure 3a, and can also help to evenly distribute mechanical and thermal stresses.

[0104] The above describes the packaging structure 7a of one embodiment of the present invention.

[0105] refer to Figure 10 , Figure 10 This is a schematic diagram of the packaging structure 8a according to an embodiment of the present invention. Figure 10 The package structure 8a shown is similar to Figure 9 The packaging structure 7a shown differs in that:

[0106] The fourth protrusion 205 is set on the third protrusion 204, and the vertical punch line 206 is set on the fourth protrusion 205.

[0107] The same effect can be achieved with encapsulation structures 3a, 4a, and 7a, which will not be elaborated here.

[0108] The above describes the packaging structure 8a of one embodiment of the present invention.

[0109] Although the present invention has been described and illustrated with reference to specific embodiments thereof, such description and illustration are not limiting of the invention. It will be readily understood by those skilled in the art that various changes can be made and equivalent elements can be substituted within the embodiments without departing from the true spirit and scope of the invention as defined by the appended claims. Illustrations may not be drawn to scale. Differences may exist between the technical representation of the invention and actual implementation due to variables in the manufacturing process, etc. Other embodiments of the invention may exist that are not specifically described. The description and illustrations should be considered illustrative rather than restrictive. Modifications can be made to adapt particular circumstances, materials, compositions, methods, or processes to the objectives, spirit, and scope of the invention. All such modifications fall within the scope of the appended claims. While the methods disclosed herein have been described with reference to specific operations performed in a particular order, it should be understood that these operations can be combined, subdivided, or reordered to form equivalent methods without departing from the teachings of the invention. Therefore, unless specifically indicated herein, the order and grouping of operations do not limit the invention.

Claims

1. A packaging structure, characterized in that, The packaging structure includes: substrate; A first protrusion is disposed on the substrate; A second protrusion is disposed on the first protrusion, and the width of the second protrusion is different from the width of the first protrusion.

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

3. The packaging structure according to claim 2, characterized in that, The packaging structure further includes: A third protrusion is disposed on the second protrusion, and the width of the third protrusion is smaller than the width of the second protrusion.

4. The packaging structure according to claim 3, characterized in that, There is a gap between the second protrusion and the third protrusion.

5. The packaging structure according to claim 3, characterized in that, The packaging structure further includes: A molding layer is disposed on the substrate and covers the first bump, the second bump, and the third bump.

6. The packaging structure according to claim 5, characterized in that, The molding layer extends between the second protrusion and the third protrusion.

7. The packaging structure according to claim 1, characterized in that, The packaging structure further includes: The chip is disposed on the substrate and located between two adjacent first bumps.

8. The packaging structure according to claim 7, characterized in that, The chip has a gap between it and the two adjacent first bumps.

9. The packaging structure according to claim 3, characterized in that, The packaging structure further includes: The fourth protrusion is disposed on the third protrusion; A vertical line is formed and positioned on the fourth protrusion.

10. The packaging structure according to claim 1, characterized in that, The first and second sidewalls of the first protrusion have curved structures and are asymmetrical.

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