A manufacturing method of high-heat-dissipation HDI circuit board

Abstract

The application provides a manufacturing method of a high-heat-dissipation HDI circuit board, which realizes chip sinking through manufacturing of a chip Die bond area; after overall assembly is completed, the overall space utilization is high, the volume of the final product can be reduced, the electronic product layout density is improved, and the product performance is improved; the chip sinking surface is connected with the holes of the copper paste through the sinking layer copper foil, and is further extended and connected to the surface copper layer, so that the heat dissipation area is greatly improved. The HDI copper paste blind hole, the buried copper block and the through-type copper paste plug hole form an integrated three-dimensional heat dissipation path, the heat conduction efficiency is high, the thermal resistance is small, the chip heat can be quickly dredged, and the heat dissipation effect is greatly improved; the structure parameters are matched with each other, the high-density interconnection, the heat dissipation performance and the processing process requirements are considered, the use requirements of high-power and high-integration electronic products are met, and the method is worth promoting.

Description

Technical Field

[0001] This invention relates to the field of circuit board technology, and more particularly to a method for manufacturing a high heat dissipation HDI circuit board. Background Technology

[0002] With the continuous iteration of high-speed computing power, high-frequency communication, high-power optical modules, and new energy power control equipment, chip integration, operating frequency, and power density are constantly increasing. This leads to a significant increase in local heat flux density within chips, placing higher demands on the thermal conductivity, interconnect density, and structural reliability of circuit boards. Traditional multilayer circuit boards mainly rely on thermally conductive vias, thick copper layers, or metal substrates for heat dissipation. However, their insulating layers have low thermal conductivity, high vertical thermal resistance, and limited thermal conductivity of micro-vias, making it difficult to meet the rapid heat dissipation and heat equalization requirements of high-power chips. This can easily lead to problems such as excessively high local temperature rise, decreased operational stability, and shortened lifespan. Summary of the Invention

[0003] The problem to be solved by the present invention is to provide a method for manufacturing a high heat dissipation HDI circuit board, thereby improving the overall heat dissipation effect of the circuit board.

[0004] To solve the above technical problems, a method for manufacturing a high heat dissipation HDI circuit board provided by this invention is provided, comprising the following steps:

[0005] S1: Preparation of core board, PP board and copper block. The area where the copper block is embedded in the core board and PP board is milled to form a hollow groove, and the copper block is subjected to browning treatment.

[0006] S2: The processing flow is: browning → one-time lamination, embedding copper blocks, stacking the core board and PP board according to the design requirements, embedding the copper blocks into the hollow grooves of the core board and PP board, and forming the sub-board through high temperature pressing;

[0007] S3: The processing flow is: browning copper reduction → laser drilling → drilling to form a matrix of HDI holes, connecting the copper block to the surface copper surface of the sub-board, and drilling through holes on the sub-board.

[0008] S4: The processing flow is: plasma → desmearing → copper plating → electroplating. Electroplating fills the HDI holes, increases the heat dissipation effect of the copper block, and facilitates chip bonding.

[0009] S5: The processing flow is: copper paste plugging holes → ceramic grinding plate → AOI → copper immersion → electroplating. The through holes near the copper block are plugged with copper paste, and after being smoothed by ceramic grinding, the surface of the copper paste is electroplated with copper using POFV to increase the three-dimensional heat dissipation effect.

[0010] S6: The processing flow is: optical imaging → etching → AOI, etching the required pattern on the surface of the sub-board and using optical scanning to confirm the quality;

[0011] S7: The processing flow is: browning → lamination. The sub-boards are processed through browning and lamination to complete the fabrication of the motherboard structure.

[0012] S8: The processing flow is: browning and copper reduction → laser drilling → drilling, drilling HDI holes and through holes. The copper block position uses a matrix HDI hole and sub-board HDI hole stacking form to connect the copper block to the surface copper surface.

[0013] S9: The processing flow is: plasma → desmearing → copper plating → electroplating. Electroplating fills the HDI holes to increase the heat dissipation effect of the copper block. Copper is electroplated on the walls of the through holes.

[0014] S10: The processing flow is: copper paste plugging → ceramic grinding plate → AOI → copper immersion → electroplating. The through holes near the copper block are plugged with copper paste, and after being smoothed by ceramic grinding, the surface of the copper paste is electroplated with copper using POFV to increase the three-dimensional heat dissipation effect.

[0015] S11: The processing flow is: optical imaging → etching → AOI, etching the required pattern on the surface of the motherboard to form a surface heat sink, and initially forming a three-dimensional heat dissipation effect, and using optical scanning to confirm the quality.

[0016] S12: The processing flow is as follows: controlled depth milling → laser controlled depth → post-processing → AOI → solder mask → character → surface treatment → shape → electrical testing → final inspection → packaging. By controlling the depth, a chip sink groove is formed, exposing a clean chip die bond area and heat dissipation area, thus completing the production of the finished board.

[0017] Preferably, in step S4, the depth of the electroplating recess in the chip bonding area is not allowed to exceed 10μm.

[0018] Preferably, in step S8, an HDI hole is not required at the chip sink position.

[0019] Preferably, in step S12, the post-processing includes sandblasting to remove waste particles sputtered on the surface.

[0020] Preferably, in step S12, the surface treatment process includes nickel-palladium-gold.

[0021] The beneficial effects of this invention are as follows: This invention provides a method for manufacturing a high-heat-dissipation HDI circuit board. By creating a chip die bond area, the chip is recessed. After overall assembly, the overall space utilization is high, the final product volume can be reduced, the electronic product layout density can be increased, and the product performance can be improved. The recessed chip surface is connected to the copper foil of the recessed layer and the holes of the copper paste, and further extends to the surface copper layer, greatly increasing the heat dissipation area. The HDI copper paste blind vias, buried copper blocks, and through-hole copper paste plugs form an integrated three-dimensional heat dissipation path with high thermal conductivity and low thermal resistance, which can quickly dissipate the chip heat and greatly improve the heat dissipation effect. The structural parameters are matched with each other, taking into account high-density interconnection, heat dissipation performance, and processing technology requirements, and adapting to the needs of high-power, highly integrated electronic products, which is worthy of promotion. Attached Figure Description

[0022] Figure 1 A schematic diagram of the circuit board structure after step S2 of the present invention is shown.

[0023] Figure 2 A schematic diagram of the circuit board structure after step S3 of the present invention is shown.

[0024] Figure 3 A schematic diagram of the circuit board structure after step S4 of the present invention is shown.

[0025] Figure 4 A schematic diagram of the circuit board structure after step S5 of the present invention is shown.

[0026] Figure 5 A schematic diagram of the circuit board structure after step S6 of the present invention is shown.

[0027] Figure 6 A schematic diagram of the circuit board structure after step S7 of the present invention is shown.

[0028] Figure 7 A schematic diagram of the circuit board structure after step S8 of the present invention is shown.

[0029] Figure 8 A schematic diagram of the circuit board structure after step S9 of the present invention is shown.

[0030] Figure 9 A schematic diagram of the circuit board structure after step S10 of the present invention is shown.

[0031] Figure 10 A schematic diagram of the circuit board structure after step S11 of the present invention is shown.

[0032] Figure 11 A schematic diagram of the circuit board structure after step S12 of the present invention is shown. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure.

[0034] Based on the embodiments described in this disclosure, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this disclosure.

[0035] refer to Figures 1-11 .

[0036] This invention provides a method for manufacturing a high heat dissipation HDI circuit board, comprising the following steps:

[0037] S1: Preparation of core board, PP board and copper block. The area where the copper block is embedded in the core board and PP board is milled to form a hollow groove, and the copper block is subjected to browning treatment.

[0038] S2: The processing flow is as follows: browning → primary lamination, embedding copper blocks, stacking the core board and PP board according to design requirements, embedding copper blocks into the slots of the core board and PP board, and forming the sub-board through high-temperature pressing (see attached document). Figure 1 (The structure shown)

[0039] S3: The processing flow is as follows: browning and copper reduction → laser drilling → drilling to form a matrix of HDI holes, connecting the copper block to the surface copper of the sub-board, and drilling through holes on the sub-board (see attached). Figure 2 (The structure shown)

[0040] S4: The processing flow is: plasma → adhesive removal → copper plating → electroplating. Electroplating fills the HDI holes, increasing the heat dissipation effect of the copper block and facilitating chip bonding (see attached document). Figure 3 (The structure shown)

[0041] S5: The processing flow is as follows: copper paste plugging → ceramic grinding plate → AOI → copper immersion → electroplating. Copper paste is used to plug the through-holes near the copper block, and after smoothing with ceramic grinding, the surface of the copper paste is electroplated with POFV copper to enhance the three-dimensional heat dissipation effect (see attached document). Figure 4 (The structure shown)

[0042] S6: The processing flow is: optical imaging → etching → AOI, etching the required pattern onto the surface of the sub-board and using optical scanning to confirm the quality (see attached document). Figure 5 (The structure shown)

[0043] S7: The processing flow is: browning → lamination. The sub-boards are processed through browning and lamination to complete the fabrication of the motherboard structure (see attached document). Figure 6 (The structure shown)

[0044] S8: The processing flow is as follows: browning and copper reduction → laser drilling → drilling, drilling HDI holes and through holes, wherein the copper block position uses a matrix of HDI holes and HDI holes stacked on the sub-board layer to connect the copper block to the surface copper surface (see attached). Figure 7 (The structure shown)

[0045] S9: The processing flow is as follows: plasma → desmearing → copper plating → electroplating. Electroplating fills the HDI holes to increase the heat dissipation effect of the copper block. Copper is electroplated on the walls of the through holes (see attached). Figure 8 (The structure shown)

[0046] S10: The processing flow is as follows: copper paste plugging → ceramic grinding plate → AOI → copper plating → electroplating. Copper paste is used to plug the through-holes near the copper block, and after smoothing with ceramic grinding, the surface of the copper paste is electroplated with POFV copper to enhance the three-dimensional heat dissipation effect (see attached document). Figure 9 (The structure shown)

[0047] S11: The processing flow is: optical imaging → etching → AOI, etching the required pattern onto the surface of the motherboard to form a surface heat sink and initially create a three-dimensional heat dissipation effect, and using optical scanning to confirm the quality (see attached). Figure 10 (The structure shown)

[0048] S12: The processing flow is as follows: controlled depth milling → laser controlled depth milling → post-processing → AOI → solder mask → lettering → surface treatment → shape → electrical testing → final inspection → packaging. The controlled depth milling creates a chip recess, exposing a clean chip die bond area and heat dissipation area, completing the finished board fabrication (see attached document). Figure 11 (The structure shown).

[0049] The principle is as follows: by creating a chip die bond area, the chip is recessed. After overall assembly, the overall space utilization is high, reducing the final product size, increasing the density of electronic product layout, and improving product performance. The recessed chip surface is connected to the copper foil of the recessed layer and the holes of the copper paste, and further extends to the surface copper layer, greatly increasing the heat dissipation area. HDI copper paste blind vias, buried copper blocks, and through-hole copper paste plugs form an integrated three-dimensional heat dissipation path with high thermal conductivity and low thermal resistance, which can quickly dissipate chip heat and significantly improve heat dissipation effect. The various structural parameters are matched with each other, taking into account high-density interconnection, heat dissipation performance, and processing technology requirements, and are suitable for the use needs of high-power, highly integrated electronic products, making it worthy of promotion.

[0050] Based on the above embodiments, in step S4, the electroplating recess depth in the chip bonding area is not allowed to exceed 10μm to ensure stable bonding.

[0051] Based on the above embodiments, in step S8, an HDI hole is not required at the chip sink position.

[0052] Based on the above embodiments, in step S12, the post-processing includes sandblasting to remove waste particles sputtered on the surface.

[0053] Based on the above embodiments, in step S12, the surface treatment process includes nickel-palladium-gold to improve the solderability of the pads.

[0054] It should be noted that the copper block embedding method is not limited to the above structure; it can be fully embedded or semi-embedded. The number of core boards on both sides of the copper block can be one or more. The HDI stacked on top of the copper block can be one or more layers. The chip sinking area can be one or more layers. The copper paste can be inserted in the motherboard process or in the daughterboard process, and after POFV electroplating, it is connected to the surface heat dissipation using HDI holes.

[0055] The above embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for manufacturing a high heat dissipation HDI circuit board, characterized in that, It includes the following steps: S1: Preparation of core board, PP board and copper block. The area where the copper block is embedded in the core board and PP board is milled to form a hollow groove, and the copper block is subjected to browning treatment. S2: The processing flow is: browning → one-time lamination, embedding copper blocks, stacking the core board and PP board according to the design requirements, embedding the copper blocks into the hollow grooves of the core board and PP board, and forming the sub-board through high temperature pressing; S3: The processing flow is: browning copper reduction → laser drilling → drilling to form a matrix of HDI holes, connecting the copper block to the surface copper surface of the sub-board, and drilling through holes on the sub-board. S4: The processing flow is: plasma → desmearing → copper plating → electroplating. Electroplating fills the HDI holes, increases the heat dissipation effect of the copper block, and facilitates chip bonding. S5: The processing flow is: copper paste plugging holes → ceramic grinding plate → AOI → copper immersion → electroplating. The through holes near the copper block are plugged with copper paste, and after being smoothed by ceramic grinding, the surface of the copper paste is electroplated with copper using POFV to increase the three-dimensional heat dissipation effect. S6: The processing flow is: optical imaging → etching → AOI, etching the required pattern on the surface of the sub-board and using optical scanning to confirm the quality; S7: The processing flow is: browning → lamination. The sub-boards are processed through browning and lamination to complete the fabrication of the motherboard structure. S8: The processing flow is: browning and copper reduction → laser drilling → drilling, drilling HDI holes and through holes. The copper block position uses a matrix HDI hole and sub-board HDI hole stacking form to connect the copper block to the surface copper surface. S9: The processing flow is: plasma → desmearing → copper plating → electroplating. Electroplating fills the HDI holes to increase the heat dissipation effect of the copper block. Copper is electroplated on the walls of the through holes. S10: The processing flow is: copper paste plugging → ceramic grinding plate → AOI → copper immersion → electroplating. The through holes near the copper block are plugged with copper paste, and after being smoothed by ceramic grinding, the surface of the copper paste is electroplated with copper using POFV to increase the three-dimensional heat dissipation effect. S11: The processing flow is: optical imaging → etching → AOI, etching the required pattern on the surface of the motherboard to form a surface heat sink, and initially forming a three-dimensional heat dissipation effect, and using optical scanning to confirm the quality. S12: The processing flow is as follows: controlled depth milling → laser controlled depth milling → post-processing → AOI → solder mask → character → surface treatment → shape → electrical testing → final inspection → packaging. By controlling the depth, a chip sink groove is formed, exposing a clean chip die bond area and heat dissipation area, thus completing the production of the finished board.

2. The manufacturing process of the high heat dissipation HDI circuit board according to claim 1, characterized in that, In step S4, the depth of the electroplating recess in the chip bonding area is not allowed to exceed 10μm.

3. The manufacturing process of the high heat dissipation HDI circuit board according to claim 1, characterized in that, In step S8, no HDI hole is needed at the chip sink position.

4. The manufacturing process of the high heat dissipation HDI circuit board according to claim 1, characterized in that, In step S12, the post-processing includes sandblasting to remove waste particles sputtered on the surface.

5. The manufacturing process of the high heat dissipation HDI circuit board according to claim 1, characterized in that, In step S12, the surface treatment process includes nickel-palladium-gold.

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