Semiconductor packaging substrate with high heat dissipation structure and preparation method and application thereof

Abstract

The invention discloses a semiconductor packaging substrate with a high heat dissipation structure and a preparation method and application thereof, and the preparation method comprises the steps: manufacturing a micro-channel pattern on a copper substrate, and then temporarily filling the micro-channel pattern with a sacrificial material, so as to stably construct a circuit and a rewiring layer above the micro-channel pattern, and finally, removing the sacrificial material, filling a final cooling medium, and connecting one end of the micro-channel image with a cooling medium flow power assisting device, so that a flowing circulating system is formed through the micro-channel image for rapid heat dissipation.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, and in particular to a semiconductor packaging substrate with a high heat dissipation structure, its preparation method, and its application. Background Technology

[0002] In 2.5D / 3D packaging, the heat generated by the chip during operation needs to be dissipated as quickly as possible to prevent the risk of device failure due to overheating, thereby extending service life and improving performance.

[0003] Existing technologies involve directly filling the packaging structure with heat-conducting metal blocks or other structures during the fabrication process to achieve heat dissipation. However, due to the influence of the overall layout, this structure can only diffuse temperature within a small range, resulting in limited heat dissipation and failing to meet the overall structure's heat dissipation requirements. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a semiconductor packaging substrate with a high heat dissipation structure, its preparation method, and its application, achieving a cooling effect that replaces traditional methods.

[0005] To achieve the above objectives, the technical solution provided by this invention is as follows: A method for fabricating a semiconductor packaging substrate with a high heat dissipation structure includes first fabricating a microchannel pattern on a copper substrate, then temporarily filling the microchannel pattern with a sacrificial material to smoothly build circuits and redistribution layers on it, finally removing the sacrificial material and filling it with a final cooling medium, and connecting a cooling medium flow assist device to one end of the microchannel pattern to realize the formation of a flowing circulation system for rapid heat dissipation.

[0006] Furthermore, the preparation steps of the method specifically include: S1: Copper plate preparation: provides structural support and a substrate with excellent thermal conductivity; S2: Dry film pressing and patterning: A photosensitive dry film is pressed onto a copper plate. Through exposure and development, the designed microchannel pattern is transferred onto the dry film. The part of the dry film that is removed is the area to be etched later. S3: Etching: Using a chemical etching solution to etch away the copper that is not protected by the dry film, forming a groove; S4: Film Removal: Remove the remaining dry film, leaving a pure copper plate with grooves; S5: Filling sacrificial material: A thermoplastic sacrificial material is filled into the etched grooves. The key characteristic of this material is that it remains solid and hard at subsequent process temperatures, but melts or decomposes when heated to a certain higher temperature. S6: Create a seed layer: Deposit a thin layer of metal on a flat surface; S7: Pressing, Exposure and Development: Coating photoresist and photolithographically creating patterns to define the positions of the metal layer under the wire bonding pads or bumps; thickening the exposed seed layer metal through electroplating to form solid pads or copper pillars; S8: Photoresist Removal and Flash Etching: Remove the photoresist and then use rapid etching to remove the seed layer that is no longer protected by the electroplated metal. S9: Molding and Grinding: The entire structure is encapsulated with molding compound and then ground to smooth the molding compound and expose the top electroplated pads / copper pillars; S10: Rewiring Layer Fabrication: Another RDL layer is fabricated on the top surface after molding for interconnection with external packaging substrates or chips; S11: Sacrificial material discharge: The entire structure is heated to the specific decomposition or melting temperature of the sacrificial material; and completely discharged through a pre-designed outlet, leaving a hollow microchannel network. S12: Filling with cooling medium: Liquid cooling medium is injected into the formed cavity microchannels through pressure or capillary action to complete the fabrication of the substrate.

[0007] Furthermore, the sacrificial material is a hot-melt resin, and the cooling medium is a phase change material.

[0008] A semiconductor packaging substrate with a high heat dissipation structure includes a substrate body, a plurality of cooling cavities are formed in the substrate body, the cooling cavities are filled with phase change material, the cooling cavities are interconnected, and the cooling cavities at the connecting edges are connected to a phase change material flow assist device.

[0009] The application of a semiconductor packaging substrate fabrication method with a high heat dissipation structure in semiconductor packaging structure, wherein a cooling medium tank is provided in any layer of the semiconductor packaging structure, and the cooling medium tank can be one or more layers.

[0010] Furthermore, when the cooling medium tank is multi-layered, the multi-layered cooling medium tanks are interconnected with each other.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: According to the requirements of the packaging structure, the present invention creates a heat dissipation channel (channel + heat dissipation copper block) at the heat dissipation point, which can realize heat dissipation by lateral conduction and exchange, as well as heat dissipation by longitudinal conduction and exchange with the environment; the phase change material inside the channel can realize temperature balance control; and the method described in this application can reduce the difficulty of channel manufacturing, while not affecting the overall stability of the structure above the channel during manufacturing. Attached Figure Description

[0012] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts.

[0013] in: Figure 1 This is a flowchart illustrating the preparation process of the present invention; Figure 2 This is a cross-sectional view of the substrate of the present invention.

[0014] Reference numerals: 1. Substrate body; 2. Cooling cavity; 3. Phase change material; 4. Assist device. Detailed Implementation

[0015] For ease of understanding, based on the technical solutions of the present invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solutions of the present invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solutions of the present invention.

[0016] See Figure 1 As shown, a method for fabricating a semiconductor packaging substrate with a high heat dissipation structure includes first fabricating a microchannel pattern on a copper substrate, then temporarily filling the microchannel pattern with a sacrificial material to smoothly build circuits and redistribution layers on it, finally removing the sacrificial material and filling it with a final cooling medium, and connecting a cooling medium flow assist device to one end of the microchannel pattern to realize the formation of a flowing circulation system for rapid heat dissipation.

[0017] The preparation steps of the method specifically include: S1: Copper plate preparation: provides structural support and a substrate with excellent thermal conductivity; S2: Dry film pressing and patterning: A photosensitive dry film is pressed onto a copper plate. Through exposure and development, the designed microchannel pattern is transferred onto the dry film. The part of the dry film that is removed is the area to be etched later. S3: Etching: Using a chemical etching solution to etch away the copper that is not protected by the dry film, forming a groove; S4: Film Removal: Remove the remaining dry film, leaving a pure copper plate with grooves; S5: Filling sacrificial material: A thermoplastic sacrificial material is filled into the etched grooves. The key characteristic of this material is that it remains solid and hard at subsequent process temperatures, but melts or decomposes when heated to a certain higher temperature. S6: Create a seed layer: Deposit a thin layer of metal on a flat surface; S7: Pressing, Exposure and Development: Coating photoresist and photolithographically creating patterns to define the positions of the metal layer under the wire bonding pads or bumps; thickening the exposed seed layer metal through electroplating to form solid pads or copper pillars; S8: Photoresist Removal and Flash Etching: Remove the photoresist and then use rapid etching to remove the seed layer that is no longer protected by the electroplated metal. S9: Molding and Grinding: The entire structure is encapsulated with molding compound and then ground to smooth the molding compound and expose the top electroplated pads / copper pillars; S10: Rewiring Layer Fabrication: Another RDL layer is fabricated on the top surface after molding for interconnection with external packaging substrates or chips; S11: Sacrificial material discharge: The entire structure is heated to the specific decomposition or melting temperature of the sacrificial material; and completely discharged through a pre-designed outlet, leaving a hollow microchannel network. S12: Filling with cooling medium: Liquid cooling medium is injected into the formed cavity microchannels through pressure or capillary action to complete the fabrication of the substrate.

[0018] The sacrificial material is hot-melt resin, and the cooling medium is a phase change material.

[0019] See Figure 2 As shown, a semiconductor packaging substrate with a high heat dissipation structure includes a substrate body, in which a plurality of cooling cavities are formed, the cooling cavities are filled with phase change material, the cooling cavities are interconnected, and the cooling cavities at the connecting edges are connected to an assist device to aid the flow of the phase change material.

[0020] The application of a semiconductor packaging substrate fabrication method with a high heat dissipation structure in semiconductor packaging structure, wherein a cooling medium tank is provided in any layer of the semiconductor packaging structure, and the cooling medium tank can be one or more layers.

[0021] Furthermore, when the cooling medium tank is multi-layered, the multi-layered cooling medium tanks are interconnected with each other.

[0022] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A method for manufacturing a semiconductor package substrate with high heat dissipation structure, comprising the steps of: manufacturing a micro-channel pattern on a copper substrate; temporarily filling the micro-channel pattern with a sacrificial material to provide a smooth surface for building circuit and redistribution layer on top; removing the sacrificial material and filling the micro-channel pattern with a final cooling medium; and connecting a cooling medium flow assisting device at one end of the micro-channel pattern to form a circulating system for fast heat dissipation.

2. The method of claim 1, wherein the method further comprises: forming a high thermal dissipation structure on the semiconductor package substrate. The manufacturing steps of the method specifically include: S1: Copper plate preparation: providing a structural support and an excellent heat conduction substrate; S2: Dry film lamination and patterning: laminating a photosensitive dry film on the copper plate, transferring the designed micro-channel pattern to the dry film by exposure and development, and removing the dry film from the areas to be etched; S3: Etching: using a chemical etching solution to etch the copper not protected by the dry film to form grooves; S4: Film removal: removing the remaining dry film, leaving a pure copper plate with grooves; S5: Filling sacrificial material: filling a hot-melt sacrificial material in the etched grooves, the key feature of which is to remain solid and hard at the temperature of subsequent processes, but to melt or decompose when heated to a specific higher temperature; S6: Seed layer preparation: depositing a thin metal layer on the flat surface; S7: Film lamination, exposure and development: coating photoresist and patterning to define the position of the wire bonding pad or under bump metal layer; thickening the exposed seed layer by electroplating to form solid pads or copper pillars; S8: Film removal and flash etching: removing the photoresist and then using fast etching to remove the seed layer that is no longer protected by the electroplated metal; S9: Plastic encapsulation and polishing: encapsulating the entire structure with plastic material and polishing to grind the molding compound flat, exposing the top electroplated pads / copper pillars; S10: Redistribution layer preparation: preparing another RDL layer on the top surface after molding for interconnection with external package substrates or chips; S11: Sacrificial material discharge: heating the entire structure to the specific decomposition or melting temperature of the sacrificial material; and completely discharging through the pre-designed outlet, leaving a hollow micro-channel network; S12: Filling cooling medium: injecting liquid cooling medium into the formed hollow micro-channel through pressure or capillary action to complete the substrate manufacturing.

3. The method of claim 2, wherein the method further comprises: forming a high thermal dissipation structure on the semiconductor package substrate. The sacrificial material is a hot-melt resin, and the cooling medium is a phase change material.

4. A semiconductor package substrate having a high heat dissipating structure, prepared by the method according to any one of claims 1 to 3, characterized by: The substrate body is provided with a plurality of cooling cavities filled with phase change material, and the cooling cavities are connected to each other and connected to an assisting device for assisting the flow of phase change material at the connected edge.

5. Use of a method according to one of claims 1 to 3 in a semiconductor package structure, characterized in that: Cooling medium grooves are provided in any layer of the semiconductor package structure, which can be one or more layers.

6. Use according to claim 5, characterized in that: When the cooling medium grooves are multiple layers, the multiple layers of cooling medium grooves are connected to each other.

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