How to create a package structure
The method addresses heat dissipation issues in semiconductor packages by directly attaching components to copper foil, enhancing heat dissipation and reliability through copper foil heat sinks and reduced inductance losses.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- UNIV OF ELECTRONICS SCI & TECH OF CHINA
- Filing Date
- 2025-02-19
- Publication Date
- 2026-06-17
AI Technical Summary
Existing semiconductor package structures face challenges in high-frequency, high-speed, and high-output operations due to inadequate heat dissipation, leading to decreased performance and reliability, particularly when operating in high-temperature environments.
A manufacturing method involving copper foil electroplating to form sacrificial pillars, forming a media layer, etching cavities, and attaching components directly to the copper foil for direct heat dissipation, with additional steps for bonding and forming conductive poles and solder layers.
The method enhances heat dissipation performance by using copper foil as a large-area heat sink, reducing inductance losses, and improving the reliability and stability of the package structure.
Smart Images
Figure 2026098877000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the technical field of semiconductor packaging, and particularly to a method for manufacturing a package structure.
Background Art
[0002] With the development and progress of electronic technology, the functions of electronic products have become increasingly powerful, the appearance of electronic products has developed in the direction of being short, small, light, and thin, promoting the development of the package structure of electronic products in the direction of high integration and miniaturization, and the embedded package of components such as chips has emerged in line with the times. At the same time, as the performance of electronic components also develops in the direction of high frequency, high speed, and high output, the heat flux density per unit area is rapidly increasing. Along with the increase in the operating environment temperature, the operating speed of electronic components decreases accordingly, the loss increases accordingly, and at the same time, it is known that the reliability of electronic products relatively decreases when operating in a high-temperature environment for a long time. If the heat generated by high-frequency, high-speed, and high-output electronic components cannot be dissipated in a timely manner, the performance and reliability of electronic products will be greatly affected. Therefore, in the major trend of high frequency, high speed, and high output, how to reasonably optimize the design of the embedded package substrate and the package body, and how to improve the heat dissipation performance of the embedded package structure has become an important issue at present.
Summary of the Invention
Problems to be Solved by the Invention
[0003] In this regard, an object of the present disclosure is to propose a method for manufacturing a package structure.
Means for Solving the Problems
[0004] Based on the above object, the present disclosure provides a method for manufacturing a package structure, step (a) of providing a copper foil, step (b) of electroplating the copper foil to form cavity sacrificial pillars, Step (c) involves pressing a media material to form a media layer that exposes the end face of the cavity sacrificial column, (d) step of forming a track layer on the media layer, Step (e) involves etching away the cavity sacrificial column to form a through cavity, The steps include (f) forming a bonding pad on the aforementioned track layer, The process includes (g) attaching the back surface of the component to the copper foil in the through cavity and wire bonding the terminals of the component to the bonding pad.
[0005] In some embodiments, the distance between the end face of the terminal and the end face of the bonding pad and the copper foil is the same.
[0006] In some embodiments, step (f) further includes the step of forming conductive poles in the track layer.
[0007] In some embodiments, The process further includes the step (h) of forming a package layer that exposes the end face of the conductive column.
[0008] In some embodiments, The process further includes step (i) of forming a solder layer on the end face of the conductive column.
[0009] In some embodiments, the step of forming a protective layer on the copper foil, located between the cavity sacrificial column and the copper foil, is further included before step (b).
[0010] In some embodiments, the material of the protective layer includes one or more of nickel, titanium, and tin.
[0011] In some embodiments, step (e) is: Step (e1) involves applying a film, exposing it, developing it, and forming a resist that exposes the cavity sacrificial column, Step (e2) involves vacuum etching the cavity sacrificial column to form a through cavity, The process includes the step of removing the resist (e3).
[0012] In some embodiments, step (f) is: This includes forming a surface treatment layer on the aforementioned track layer.
[0013] In some embodiments, the surface treatment layer is formed by a nickel-palladium-gold process. [Effects of the Invention]
[0014] As can be seen from the above, the method for manufacturing a package structure according to this disclosure includes the steps of: (a) providing copper foil; (b) electroplating the copper foil to form cavity sacrificial columns; (c) pressing a medium material to form a medium layer that exposes the end faces of the cavity sacrificial columns; (d) forming a line layer on the medium layer; (e) etching off the cavity sacrificial columns to form a through cavity; (f) forming a bonding pad on the line layer; and (g) attaching the back surface of a component to the copper foil in the through cavity and wire bonding the terminals of the component to the bonding pad. With this manufacturing method, the component is directly attached to the copper foil, the copper foil acts as a large-area heat sink, and the heat generated when the component is in operation is quickly dissipated, greatly improving the heat dissipation performance of the embedded package structure. [Brief explanation of the drawing]
[0015] To more clearly illustrate the technical concepts in this disclosure or related technologies, the following briefly introduces the accompanying drawings that may be used in the descriptions of the embodiments or related technologies. It is obvious that the accompanying drawings in the following descriptions are merely embodiments of this disclosure, and a person skilled in the art can obtain other accompanying drawings based on these, without requiring any creative effort. In the accompanying drawings, the thickness and shape of some layers and regions may be exaggerated for ease of understanding and description. [Figure 1(a)]It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(b)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(c)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(d)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(e)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(f)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(g)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(h)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(i)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 1(j)] It is a schematic cross-sectional view of an intermediate structure of each step of a method for manufacturing a package structure according to an embodiment of the present disclosure. [Figure 2] It is a schematic view of a package structure according to an embodiment of the present disclosure. [[ID=Unless otherwise defined, technical or scientific terms used in the embodiments of this disclosure should have the general meaning understood by a person with general skills in the art to which this disclosure belongs. The terms “first,” “second,” and similar terms used in the embodiments of this disclosure do not indicate any order, number, or importance, but are used solely to distinguish different components. Similar terms such as “includes” or “contains” mean that the element or object preceding the term covers the elements or objects and their equivalents listed after the term, but do not exclude other elements or objects. Similar terms such as “connected” or “linked” are not limited to physical or mechanical connections, but may also include electrical connections, whether direct or indirect. Terms such as “up,” “down,” “left,” and “right” are used solely to describe relative positional relationships, and these relative positional relationships may change if the absolute position of the described object changes.
[0018] In related technologies, embedded packages are realized by attaching components such as chips to a polymer frame or core plate with pre-installed cavities, and then pressing a media material onto it. Due to the limitations of the heat dissipation properties of organic polymer materials, it is difficult to fundamentally solve the heat dissipation problem of high-frequency, high-speed, high-power embedded products.
[0019] To solve the heat dissipation problem of embedded products, a technique in which cavities are pre-fabricated in a metal (e.g., copper) plate, components such as chips are attached to the pre-prepared cavities, and then a media material is pressed onto them for packaging is attracting attention. However, such a method involves a complex processing flow and is costly.
[0020] In this regard, embodiments of the present disclosure provide a method for manufacturing a package structure. The manufacturing method includes the steps of: (a) providing copper foil; (b) electroplating the copper foil to form cavity sacrificial columns; (c) pressing a medium material to form a medium layer that exposes the end faces of the cavity sacrificial columns; (d) forming a line layer on the medium layer; (e) etching off the cavity sacrificial columns to form a through cavity; (f) forming a bonding pad on the line layer; and (g) attaching the back surface of a component to the copper foil in the through cavity and wire bonding the terminals of the component to the bonding pad. With such a manufacturing method, the component is directly attached to the copper foil, the copper foil acts as a large-area heat sink, and the heat generated when the component is in operation is quickly dissipated, greatly improving the heat dissipation performance of the embedded package structure.
[0021] Figures 1(a) to 1(j) are schematic cross-sectional views of intermediate structures at each step of the method for manufacturing a package structure according to the embodiments of this disclosure. As shown in Figures 1(a) to 1(j), the manufacturing method includes the following:
[0022] First, step (a) is to provide the copper foil 100, as shown in Figure 1(a). Here, the thickness of the copper foil 100 may be 200 μm.
[0023] Next, the copper foil 100 is electroplated to form a protective layer 101 and a cavity sacrificial column 102 - step (b), shown in Figure 1(b). Optionally, the protective layer 101 is a metal etching protective layer, and the material of the protective layer 101 is one or more selected from nickel, titanium, and tin. Optionally, the cavity sacrificial column 102 may be a copper column.
[0024] In some embodiments, step (b) specifically includes applying a film to one surface of the copper foil 100, exposing and developing it to form a first layer, then electroplating to form a protective layer 101, then electroplating to form a cavity sacrificial column 102, and finally removing the first layer to obtain the protective layer 101 and the cavity sacrificial column 102.
[0025] Subsequently, the media material is pressed to form a media layer 201 that exposes the end face of the cavity sacrificial column 102 - step (c), shown in Figure 1(c). Note that the technical effect of exposing the end face of the cavity sacrificial column 102 can be achieved by mechanical polishing.
[0026] Next is step (d), in which the line layer 203 is formed on the media layer 201, as shown in Figure 1(d).
[0027] In some embodiments, step (d) specifically includes forming a metal seed layer 202 on a medium layer 201, then applying a film, exposing and developing it to form a second layer, then electroplating it, and finally removing the second layer and etching the metal seed layer 202 to form a track layer 203.
[0028] Subsequently, the cavity sacrificial column 102 is etched away to form a through cavity - step (e), shown in Figure 1(e).
[0029] In some embodiments, step (e) may include (e1) forming a resist that exposes the cavity sacrificial columns 102 by applying, exposing, and developing the film, then (e2) vacuum etching the cavity sacrificial columns 102 to form through cavities, and finally (e3) removing the resist. Here, the protective layer 101 can serve to prevent the copper foil 100 from being etched and to protect the copper foil 100.
[0030] Next, a solder resist layer 301 is fabricated - step (f), shown in Figure 1(f). Here, the solder resist layer 301 exposes a portion of the line layer 203. Note that the solder resist layer 301 does not need to overlap with the subsequent bonding pad 304 and conductive pole 302.
[0031] In some embodiments, step (f) includes first performing solder resist printing, then exposure, development, baking with nitrogen gas, and finally ultraviolet light curing to form a solder resist layer 301.
[0032] Subsequently, step (g) is performed to form stumps 302 in the track layer 203, as shown in Figure 1(g). Selectively, the stumps 302 are manufactured by an electroplating method. Specifically, the manufacturing of the stumps 302 may include applying a film, exposing it, developing it to form a third layer, electroplating it, and finally removing the third layer.
[0033] Next, a surface treatment layer 303 is formed on the track layer 203 and the conductive pole 302, and the surface-treated track layer 203 forms a bonding pad 304 - step (h), shown in Figure 1(h).
[0034] Selectively, the surface treatment layer 303 is formed by the nickel-palladium-gold process (ENEPIG).
[0035] Subsequently, the back surface of component 401 is attached to the protective layer 101 in the through cavity, and the terminals of component 401 and the bonding pad 304 are wire-bonded—step (i), as shown in Figure 1(i). Direct contact between component 401 and the copper foil 100 facilitates the rapid dissipation of heat generated during the operation of component 401, thereby improving the heat dissipation performance of the embedded package structure.
[0036] In some embodiments, component 401 may be attached using an adhesive such as epoxy resin, and this disclosure is not limited thereto.
[0037] By selectively controlling the depth of the through-cavity and the thickness of the bonding pad 304, the distance between the terminal end faces of component 401 and the bonding pad 304 and the copper foil 100 is made the same. In other words, by positioning the terminal end faces of component 401 and the bonding pad 304 at the same height, inductance losses due to lead arcs can be reduced, improving the overall stability of the package structure's performance.
[0038] Component 401 may be an active element (e.g., a transistor, IC component, logic circuit element, power amplifier) or a passive element (e.g., a capacitor, inductor, resistor). This disclosure is not limited thereto.
[0039] Next, the package is formed using a molding material to create a package layer 501 - step (j), shown in Figure 1(j). Here, the polished package layer exposes the end faces of the conductive columns 302.
[0040] Finally, a solder layer 402 is formed on the end face of the conductive column 302 to form a pin in the package structure - step (k), as shown in Figure 1(j).
[0041] Figure 2 shows the package structure manufactured in steps (a) to (k). As shown in Figure 2, the package structure includes copper foil 100, a medium layer 201, a line layer 203, a bonding pad 304 (bond finger), and a component 401, wherein the medium layer 201 and the line layer 203 are sequentially provided on the copper foil 100, the medium layer 201 includes a through cavity, the component 401 is provided on the copper foil 100 within the through cavity, the bonding pad 304 is provided on the line layer 203, and the terminals of the component 401 are connected to the bonding pad 304 by wires. Furthermore, the line layer 203 is further provided with conductive posts 302 and a package layer 501, the conductive posts 302 may be copper posts. The package layer 501 exposes the end faces of the conductive posts 302. Selectively, a solder layer 402 is provided on the end faces of the conductive posts 302. This allows the conductive pole 302 to function as a pin in the package structure, thereby increasing the flexibility of the package structure's layout.
[0042] In some embodiments, a protective layer 101 is further provided between the copper foil 100 and the component 401, and the material of the protective layer 101 is metal. The protective layer 101 can protect the copper foil 100 from etching during the fabrication of the package structure without affecting the heat dissipation of the component 401 through the copper foil 100.
[0043] In some embodiments, the distance between the end faces of the terminals of component 401 and the end faces of the bonding pad 304 and the copper foil 100 is the same. This structure reduces the curvature of the leads between the terminals of component 401 and the bonding pad 304, thereby reducing inductance loss due to lead arcs and improving the overall stability of the package structure.
[0044] As a step that those skilled in the art should understand, the consideration of the above-mentioned arbitrary embodiments is merely illustrative and is not intended to suggest that the scope of the present disclosure (including the claims) is limited to these examples. In the concept of the present disclosure, the technical features in the above-mentioned embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the embodiments of the present disclosure as described above, which for brevity are not provided in detail.
[0045] The embodiments of this disclosure are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the attached claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this disclosure should be included within the scope of protection of this disclosure. [Explanation of Symbols]
[0046] 100 Copper foil, 101 Protective layer, 102 Cavity sacrificial column, 201 Medium layer, 202 Metal seed layer, 203 Line layer, 301 Solder resist layer, 302 Conduction column, 303 Surface treatment layer, 304 Bonding pad, 401 Components, 402 Solder layer, 501 Package layer
Claims
1. A method for creating a package structure, Step (a) of providing copper foil, Step (b) electroplating the copper foil to form a cavity sacrificial column, Step (c) involves pressing a media material to form a media layer that exposes the end face of the cavity sacrificial column, The steps include (d) forming a line layer on the media layer, Step (e) of etching away the cavity sacrificial column to form a through cavity, The steps include (f) forming a bonding pad on the aforementioned track layer, A method for manufacturing a package structure, comprising the step (g) of attaching the back surface of a component to the copper foil in the through cavity and wire bonding the terminals of the component to the bonding pad.
2. The manufacturing method according to claim 1, characterized in that the distance between the end face of the terminal and the end face of the bonding pad and the copper foil are the same.
3. The manufacturing method according to claim 1, further comprising the step of forming conductive poles in the track layer before step (f).
4. The manufacturing method according to claim 3, further comprising the step (h) of forming a package layer that exposes the end face of the conductive column.
5. The manufacturing method according to claim 4, further comprising step (i) of forming a solder layer on the end face of the conductive column.
6. The method of manufacture according to claim 1, further comprising the step of forming a protective layer on the copper foil located between the cavity sacrificial column and the copper foil, prior to step (b).
7. The manufacturing method according to claim 6, characterized in that the material of the protective layer includes one or more of nickel, titanium, and tin.
8. Step (e) is, Step (e1) involves applying a film, exposing it, developing it, and forming a resist that exposes the cavity sacrificial column, Step (e2) involves vacuum etching the cavity sacrificial column to form a through cavity, The manufacturing method according to claim 1, characterized by comprising the step (e3) of removing the resist.
9. Step (f) is, The manufacturing method according to claim 1, characterized by comprising forming a surface treatment layer on the aforementioned track layer.
10. The manufacturing method according to claim 9, characterized in that the surface treatment layer is formed by a nickel-palladium-gold process.