TW202406425A - Manufacturing method of circuit board - Google Patents

Abstract

A circuit board manufacturing method and a circuit board structure are provided. The method includes providing an insulating substrate and a metal circuit formed on the insulating substrate; forming a dielectric layer film on the metal circuit, and enabling the dielectric layer film to sink into gaps of the metal circuit to contact the insulating substrate; covering an imprinting mold having a plurality of protruding pillar structures on the dielectric layer film, and performing an imprinting operation, so that the plurality of protruding pillar structures of the imprinting mold are pressed into the dielectric layer film; and removing the imprinting mold from the dielectric layer film, so that the dielectric layer film forms a plurality of imprinting holes having shapes corresponding to the plurality of protruding pillar structures of the imprinting mold, respectively.

Description

Circuit board manufacturing method and circuit board structure

The present invention relates to a method of manufacturing a circuit board, and in particular to a method of manufacturing a circuit board with embossed holes and a circuit board structure.

In the prior art circuit board manufacturing method, a plurality of laser holes are sequentially formed on the dielectric layer film through laser drilling during the layer build-up operation. However, in the existing laser drilling process, a drill bit can only form one laser hole in one drilling operation. The more holes are drilled, the longer the processing time is required. In addition, laser drilling also has aperture limitations.

The technical problem to be solved by the present invention is to provide a circuit board manufacturing method and circuit board structure in view of the shortcomings of the existing technology.

In order to solve the above technical problems, one of the technical solutions adopted by the present invention is to provide a manufacturing method of a circuit board, which includes: providing an insulating substrate and a metal circuit formed on the insulating substrate; forming a dielectric Layer a thin film on the metal lines, and make the dielectric layer film fall into the gap between the metal lines to contact the insulating substrate; cover an imprint mold with a plurality of protruding pillar structures on the on the dielectric layer film, and perform an imprinting operation so that the plurality of protruding pillar structures of the imprinting mold are pressed into the dielectric layer film and are positioned corresponding to the top of the metal circuit; and removing the imprinting mold from the dielectric layer film, so that the dielectric layer film has a plurality of imprints with shapes respectively corresponding to the plurality of protruding pillar structures of the imprinting mold. Fill the hole.

In order to solve the above technical problems, another technical solution adopted by the present invention is to provide a circuit board structure, which includes: an insulating substrate; a metal circuit formed on the insulating substrate; and a dielectric layer film, It is formed on the metal lines and sinks into the gaps between the metal lines to contact the insulating substrate; wherein the dielectric layer film has a shape corresponding to a plurality of protruding pillar structures of an imprinting mold. A plurality of imprinted filling holes are filled with a plurality of conductive metals on the inside respectively; wherein, the dielectric layer film is an ABF build-up film or an ABF-like build-up film.

The beneficial effect of the present invention is that the circuit board manufacturing method provided by the present invention can be achieved by "covering an embossing mold with a plurality of protruding pillar structures on the dielectric layer film and performing an embossing operation. , so that the plurality of protruding pillar structures of the imprinting mold are pressed into the dielectric layer film and are positioned corresponding to the top of the metal lines" and "moving the imprinting mold from the intermediary The technical solution is to remove the electrical layer film so that the dielectric layer film has a plurality of embossed filling holes whose shapes respectively correspond to the plurality of convex pillar structures of the embossed mold, so that in a single pass Multiple embossing holes are produced at the same time in the embossing operation to meet the needs of products with a large number of holes and can greatly shorten the operation time.

Furthermore, compared with the traditional laser drilling process, the circuit board manufacturing method of the present invention can simultaneously produce multiple holes with smaller diameters (such as holes of 5 microns to 100 microns), thereby breaking through the traditional laser drilling process. Hole process limits.

In order to further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only for reference and illustration and are not used to limit the present invention.

The following is a specific example to illustrate the disclosed embodiments of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depictions based on actual dimensions, as is stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of the present invention.

It should be understood that although terms such as “first”, “second” and “third” may be used herein to describe various elements or signals, these elements or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another component or one signal from another signal. In addition, the term "or" used in this article shall include any one or combination of multiple associated listed items, depending on the actual situation.

[Circuit board manufacturing method]

Referring to FIGS. 1A to 1J , an embodiment of the present invention provides a circuit board manufacturing method, and the circuit board manufacturing method includes steps S101 to S110 . It must be noted that the sequence of each step and the actual operation method described in this embodiment can be adjusted according to needs and are not limited to those described in this embodiment.

As shown in Figure 1A, the step S101 includes: providing a core material. The core material includes an insulating substrate 1 (or core) and a metal coating layer 2 formed on the insulating substrate 1 . Wherein, the material of the insulating substrate 1 can be, for example, a fiberglass substrate, a glass substrate, a paper substrate, a composite substrate, a BT substrate, or a FR-4 substrate or other substrates with electrical insulation properties, and the metal coating layer 2 It may be, for example, a conductive material such as metal copper foil or copper seed layer, but the invention is not limited thereto.

As shown in FIG. 1B , the step S102 includes forming a patterned photoresist mask 3 on the metal coating layer 2 . More specifically, the photoresist mask 3 is formed on a side surface of the metal coating layer 2 away from the insulating substrate 1 . The photoresist mask 3 can be formed, for example, by sequentially covering the photoresist (such as pressing dry film photoresist or coating wet film photoresist), and exposing and developing the photoresist. formed by the manufacturing process. Furthermore, a plurality of gaps 31 are formed on the inner side of the photoresist mask 3 , and the portion of the metal coating layer 2 that is not shielded by the photoresist mask 3 is exposed to the plurality of gaps 31 to provide conductive metal. Fill in it.

As shown in FIG. 1C , step S103 includes forming a plurality of conductive metals 4 in the gaps 31 by electroplating. More specifically, the plurality of conductive metals 4 are formed extending from the metal coating layer 2 in a direction opposite to the insulating substrate 1 and filled in the plurality of gaps 31 .

As shown in FIG. 1D , the step S104 includes: removing the photoresist mask 3 and forming the plurality of conductive metals 4 into a metal circuit 5 . More specifically, in order to form the plurality of conductive metals 4 into metal lines 5, in this embodiment, after removing the photoresist mask 3, step S104 further includes: The coating layer 2 is etched (such as chemical etching) to remove the portion of the metal coating layer 2 that is not covered by the plurality of conductive metals 4, so that the plurality of conductive metals 4 are formed into the metal Line 5. That is to say, the removed part of the metal coating layer 2 is the part of the metal coating layer 2 that was originally covered by the photoresist mask 3 .

Simply put, step S104 includes: providing a circuit board semi-finished product, which includes an insulating substrate 1 and a metal circuit 5 formed on the insulating substrate 1 . Wherein, the metal circuit 5 has conductivity, and the metal circuit 5 may include, for example, patterned conductive circuits and metal pads.

It is worth mentioning that, as in the above steps S101 to S104, the metal circuit 5 is formed by a semi-additive method or a modified semi-additive method, but the present invention is not limited thereto. The metal circuit 5 may also be formed on the insulating substrate 1 by, for example, a subtractive method or a fully additive method.

As shown in FIG. 1E , the step S105 includes: forming a dielectric layer film 6 on the circuit board semi-finished product, and making the dielectric layer film 6 cover the metal circuit 5 and sink into the metal circuit 5 The gap between them is so as to contact the surface of the insulating substrate 1 connected to the metal circuit 5 .

In this embodiment, the dielectric layer film 6 is an ABF dielectric layer film, that is, Ajinomoto Build-up Film (ABF). More specifically, the dielectric layer film 6 is a thermosetting resin material. The dielectric layer film 6 can be softened, for example, by vacuum hot pressing, so as to fall into the gap between the metal lines 5 . The softened dielectric layer film 6 can, for example, be placed in an oven at a soft baking temperature (<150 degrees C, such as 90~ 150 degrees C) for soft baking, and after removing the soft film structure M1 (as shown in Figure 1G), perform a hard bake at a hard baking temperature (>150 degrees C, such as 150~200 degrees C) to complete the solidification of the material.

More specifically, as shown in Figure 1F and please refer also to Figures 2A to 2D. The step S106 includes: covering an imprinting mold M on the dielectric layer film 6 and performing an imprinting operation. Wherein, the embossing mold M includes a plurality of convex pillar structures M12, and the plurality of convex pillar structures M12 of the embossing mold M can be removed from a top of the dielectric layer film 6 during the embossing operation. The surface (the side surface of the dielectric layer film 6 away from the insulating substrate 1) is pressed into the dielectric layer film 6 and corresponds to the position of the metal circuit 5. For example, the plurality of protruding pillar structures M12 are Located above the metal pad of metal line 5.

More specifically, the imprinting mold M includes: a soft film structure M1 and a hard substrate M2 disposed on one side surface of the soft film structure M1. Wherein, the soft film structure M1 has a soft film base material M11 in a plate or sheet shape and the plurality of protruding pillar structures M12 formed from one side surface of the soft film base material M11, and the hard substrate M2 is disposed on a side surface of the soft film base material M11 away from the plurality of protruding column structures M12 to support the soft film structure M1.

In this embodiment, the material of the soft film structure M1 may be, for example, a thermosetting polymer or a UV-curing polymer. Furthermore, the hard substrate M2 may be, for example, a glass substrate, but the present invention is not limited thereto. In addition, the plurality of protruding pillar structures M12 of the imprinting mold M can be, for example, each in the shape of a cylinder, and have a diameter D between 5 microns and 100 microns and a diameter D between 5 microns and 100 microns. A height H (as shown in Figure 1F), but the present invention is not limited thereto.

During the imprinting operation, the plurality of protruding pillar structures M12 are disposed toward the direction of the dielectric layer film 6 , and a force can be applied to the hard substrate M2 so that the plurality of protruding pillars M12 The structure M12 can be pressed into the dielectric layer film 6 and is positioned above the metal circuit 5 . In some cases, imprinting cannot make the plurality of protruding pillar structures M12 of the imprinting mold M directly contact the metal circuit 5, and there will be some residual material (such as: ABF) between the protruding pillar structures M12 and the metal circuit 5. SiO ₂ particles in the dielectric layer film 6), but the present invention is not limited thereto.

Furthermore, in the imprinting operation, the dielectric layer film 6 can be heated to a softening temperature, for example, during a vacuum hot pressing process, and the softening temperature of the dielectric layer film 6 is lower than that of glass. Transfer temperature. Moreover, the hardness (such as material hardness) of the dielectric layer film 6 (such as ABF resin material) can be less than the hardness of the plurality of protruding pillar structures M12 of the imprinting mold M after being heated to the softening temperature. , so that the plurality of protruding pillar structures M12 of the imprinting mold M can be pressed into the dielectric layer film 6 .

In this embodiment, the softening temperature of the dielectric layer film 6 is between 70°C and 130°C, and the glass transition temperature of the dielectric layer film is between 150°C and 200°C. However, the present invention Not limited to this.

Further, please refer to FIGS. 2A to 2D . The imprint mold M may be formed, for example, by an imprint mold manufacturing method, including steps S201 to S204 . It should be noted that the imprinting mold M in this embodiment is formed in the above manner, but the invention is not limited thereto.

As shown in Figure 2A, the step S201 includes: providing a master mold N, and the master mold N includes a hard mold base material N1 in a plate or sheet shape and a hard mold base material N1 formed from the hard mold base material N1. A plurality of protruding structures N2 are formed on the side surface. In this embodiment, the master mold N may be, for example, a nickel mold, a silicon mold, or a photoresist mold, but the invention is not limited thereto.

As shown in Figure 2B, the step S202 includes: coating (such as spin coating) a soft film material on the side of the master mold N having the plurality of protruding structures N2, so as to A soft film structure M1 is formed on N (for example: drying the solvent inside the soft film material). The soft film structure M1 has a soft film base material M11 and a plurality of protruding column structures M12, and the plurality of protruding column structures M12 of the soft film structure M1 are geometrically complementary to the plurality of protruding structures N2 of the master mold N. . That is to say, the plurality of protruding pillar structures M12 of the soft film structure M1 are formed by sinking the soft film material into the gaps between the plurality of protruding structures N2 of the master mold N.

As shown in FIG. 2C , the step S203 includes: attaching a hard substrate M2 (such as a glass substrate) to a side surface of the soft film base material M11 away from the plurality of protruding pillar structures M12 to fix the soft film. Structure M1 acts as a support. The soft film structure M1 and the hard substrate M2 together form an imprinting mold M. If the material of the soft film structure M1 is a thermosetting polymer, step S203 further includes thermally baking and solidifying the soft film structure M1. Alternatively, if the material of the soft film structure M1 is a UV-curable polymer, step S203 further includes UV curing the soft film structure M1.

As shown in Figure 2D, the step S204 includes: separating the imprinting mold M from the portion where the plurality of protruding pillar structures M12 of the soft film structure M1 are connected to the plurality of protruding structures N2 of the master mold N, To complete the preparation of the imprinting mold M.

It is worth mentioning that the manufacturing method of the circuit board of this embodiment is to use the plurality of bump structures M12 of the soft film structure M1 to imprint the dielectric layer film 6 . In this way, in the process of mass production of circuit boards, circuit boards of different batches or material numbers can use the same master mold N (the master mold itself is a gravure plate that can reproduce the embossed soft film) to produce a soft film structure M1 A plurality of embossing molds M are used to perform embossing operations. In other words, a new imprinting mold M can be used for each imprinting operation, thereby improving the stability of product manufacturing.

Nevertheless, the manufacturing method of the circuit board of the present invention is not limited to the above embodiment. In another embodiment of the present invention, as shown in FIG. 3 , the manufacturing method of the circuit board may also directly use the master mold N (relief plate) as an imprinting mold M to stamp the dielectric. A layer of film 6 is used for imprinting.

It is also worth mentioning that, please continue to refer to Figure 1F. The plurality of protruding pillar structures M12 of the imprinting mold M can be pressed into the dielectric layer film 6 and correspond to the position of the metal circuit 5. For example, it is located above the metal pad in the metal circuit 5 . Furthermore, the imprinting operation of the circuit board manufacturing method of this embodiment may, for example, adopt Nanoimprint Lithography (NIL) technology.

Further, as shown in FIG. 1G , after step S106 (imprinting operation), step S107 includes: removing the imprinting mold M from the dielectric layer film 6 so that the dielectric layer The electrical layer film 6 is formed with a plurality of embossing holes 7 whose shapes respectively correspond to the plurality of protruding pillar structures M12 of the embossing mold M. Wherein, each of the imprinted filling holes 7 is formed by being recessed from the top surface of the dielectric layer film 6 (the side surface of the dielectric layer film 6 away from the insulating substrate 1) toward the direction of the insulating substrate 1, and each Each of the embossed holes 7 exposes at least part of the metal circuit 5 (such as a metal pad) to the external environment.

It is worth mentioning that the manufacturing method of the circuit board according to the embodiment of the present invention uses an embossing mold M to perform embossing operations, thereby forming a plurality of embossed filling holes 7 on the dielectric layer film 6 . Thereby, the manufacturing method of the circuit board according to the embodiment of the present invention can replace the traditional laser drilling process.

Furthermore, compared with the traditional laser drilling process, a drill bit can only form one laser hole in one drilling operation. The circuit board manufacturing method according to the embodiment of the present invention can print multiple parts of the mold M. The protruding pillar structure M12 can simultaneously produce multiple imprinted filling holes 7 in a single imprinting operation, so as to meet the needs of products with a large number of filling holes and greatly shorten the operation time.

In addition, compared with the traditional laser drilling process, the circuit board manufacturing method of the embodiment of the present invention can simultaneously produce multiple holes with smaller diameters (such as holes of 5 microns to 100 microns), thereby breaking through the traditional laser drilling process. The process limits of shot drilling.

Furthermore, after the dielectric layer film 6 is formed with a plurality of imprinted holes 7, the step S107 further includes performing a curing operation on the dielectric layer film 6 (such as placing the circuit board semi-finished product). Put it into an oven and bake it), so that the dielectric layer film 6 changes from a softened state to a solidified state. It is worth mentioning that the softened dielectric layer film 6 can, for example, be put into an oven at a soft baking temperature (<150 degrees C, such as 90 to 150 degrees C) after the imprinting operation in FIG. 1F ), perform soft baking, and after removing the soft film structure M1 (as shown in Figure 1G), perform hard baking at a hard baking temperature (>150 degrees C, such as 150~200 degrees C) to complete the solidification of the material.

In addition, in order to make the formation positions of the plurality of embossing holes 7 more accurate, before the plurality of protruding pillar structures M12 of the embossing mold M are pressed into the dielectric layer film 6, the circuit of the embodiment of the present invention The manufacturing method of the board further includes a positioning operation (not shown). The alignment operation includes: aligning the plurality of protruding pillar structures M12 of the imprinting mold M with at least part of the metal circuit 5 (such as a metal pad), thereby facilitating the subsequent imprinting operation, However, the present invention is not limited to this.

As shown in FIG. 1H , the step S108 includes forming a metal deposition layer 8 on the dielectric layer film 6 . The metal deposition layer 8 covers the top surface of the dielectric layer film 6 (the side surface of the dielectric layer film 6 away from the insulating substrate 1), and extends to cover the hole walls of the plurality of imprinted filling holes 7 and on at least part of the metal lines 5 (such as metal pads).

Furthermore, the metal deposition layer 8 may be formed by, for example, electroless copper plating, sputtering, etc., and the material of the metal deposition layer 8 may be, for example, copper metal, but the invention is not limited thereto. .

As shown in FIG. 1I , the step S109 includes forming another patterned photoresist mask 9 on the metal deposition layer 8 . More specifically, the other photoresist mask 9 is formed on a side surface of the metal deposition layer 8 away from the insulating substrate 1 . Similar to step S102 , the other photoresist mask 9 may be formed, for example, by sequentially covering the photoresist (such as pressing dry film photoresist, or coating wet film photoresist), and The resist is formed by processes such as exposure and development. Furthermore, a plurality of other gaps 91 are formed on the inner side of the other photoresist mask 9, and at least part of the gaps 91 among the plurality of other gaps 91 correspond to the positions of the plurality of imprint pots respectively. Hole 7. The portions of the metal deposition layer 8 that are not shielded by the other photoresist mask 9 are exposed to a plurality of other gaps 91 to provide conductive metal filling therein.

As shown in FIG. 1J , step S110 includes forming a plurality of other conductive metals 10 in a plurality of other gaps 91 inside the other photoresist mask 9 by electroplating. More specifically, the plurality of other conductive metals 10 are first filled in the plurality of imprinted holes 7, and are further formed extending from the metal deposition layer 8 in a direction opposite to the insulating substrate 1, and filled in all the other conductive metals 10. A plurality of other gaps 91 inside the other photoresist mask 9 are placed in a plurality of other gaps 91 to facilitate the subsequent formation of build-up conductive circuits.

After step S110, the manufacturing method of the circuit board according to the embodiment of the present invention can further remove the other photoresist mask 9 similar to step S104, and allow the other conductive metal 10 to be formed as another build-up layer. Metal circuits, and the above-mentioned steps S105 to S110 can be repeated according to design requirements to complete the layer-adding operation of the printed circuit board.

[Circuit board structure]

The above is about the manufacturing method of the circuit board according to the embodiment of the present invention. An embodiment of the present invention further provides a circuit board structure, which includes an insulating substrate 1, a metal circuit 5, and a dielectric layer film 6.

The metal circuit 5 is formed on the insulating substrate 1 .

The dielectric layer film 6 is formed on the metal lines 5 and is embedded in the gaps between the metal lines 5 to contact the insulating substrate 1 .

The dielectric layer film 6 has a plurality of embossed filling holes 7 whose shapes respectively correspond to the plurality of convex pillar structures M12 of an embossing mold M, and the insides thereof are respectively filled with a plurality of conductive metals 10 .

The dielectric layer film 6 is an ABF build-up film, such as Ajinomoto Build-up Film or other ABF-like build-up films with similar properties produced by other companies (such as Taiwan Crystal Technology). The dielectric layer film 6 is softened by vacuum hot pressing and falls into the gap between the metal lines 5 .

More specifically, the material thickness of the dielectric layer film 6 (ABF or ABF-like build-up film) is approximately between 5 microns and 100 microns, and is supported by a PET film carrier. The film is softened by vacuum hot pressing and falls into the gap between the metal lines 5. Then the PET film carrier is removed, and finally the dielectric layer film 6 is baked at high temperature (150~200°C). Let it polymerize and solidify.

In terms of material composition, the composition of the dielectric layer film 6 mainly includes additives such as epoxy resin, silicon dioxide, and catalysts.

In terms of material properties, the dielectric layer film 6 (after baking) has a glass transition temperature (Tg) of approximately 150°C to 200°C, and a silicon dioxide weight percentage of approximately 15wt% to 70wt %, a first thermal expansion coefficient (25~150°C) is about 10 ppm/°C to 40 ppm/°C, a second thermal expansion coefficient (150~240°C) is about 65 ppm/°C to 135 ppm/°C, a dielectric constant Dk (@5.8GHz) of approximately 3 to 3.5, a tensile strength of approximately 80 MPa to 120 MPa, and a Young's coefficient of approximately 3 GPa to 10 GPa. The above material properties correspond to those of ABF or ABF-like build-up films. That is to say, a film with the above material characteristics complies with the protective spirit of the dielectric layer film referred to in the present invention and belongs to the protection scope of the present invention. Wherein, the glass transition temperature (Tg) can be tested by scanning calorimetry according to ASTM D7426-08 and ASTM-E1356, for example. The thermal expansion coefficient can be tested using a thermomechanical analyzer according to ASTM D3386 and ASTM E831, for example. The dielectric constant can be tested, for example, according to the ASTM D150 dielectric constant test method. The tensile strength can be tested, for example, according to ASTM D638 tensile test standard. The Young's modulus can be tested, for example, according to the ASTM E111 Young's modulus test standard.

[Beneficial effects of the embodiment]

The beneficial effect of the present invention is that the circuit board manufacturing method provided by the embodiment of the present invention can be achieved by "covering an embossing mold with a plurality of protruding pillar structures on the dielectric layer film, and performing an embossing process. printing operation, so that the plurality of protruding pillar structures of the embossing mold are pressed into the dielectric layer film and positionally correspond to the top of the metal lines" and "remove the embossing mold from the The technical solution is to remove the dielectric layer film so that the dielectric layer film has a plurality of embossed filling holes whose shapes respectively correspond to the plurality of protruding pillar structures of the embossed mold, so that in Multiple embossing holes are produced simultaneously in a single embossing operation to meet the needs of products with a large number of holes and can greatly shorten the operation time.

Furthermore, compared with the traditional laser drilling process, the circuit board manufacturing method of the present invention can simultaneously produce multiple holes with smaller diameters (such as holes of 5 microns to 100 microns), thereby breaking through the traditional laser drilling process. Hole process limits.

The contents disclosed above are only preferred and feasible embodiments of the present invention, and do not limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made by using the description and drawings of the present invention are included in the application of the present invention. within the scope of the patent.

1: Insulating substrate 2: Metal coating layer 3: Photoresist mask 31: Gap 4: Conductive metal 5: Metal lines 6: Dielectric layer film 7: Imprint and fill holes 8: Metal deposition layer 9: Photoresist mask 91: Gap 10: Conductive metal M: Imprinting mold M1: Soft film structure M11: Soft film base material M12:Protruding column structure M2: Hard substrate N:Mother mold N1: Hard mold base material N2:Protruding structure D: diameter H: height

1A is a schematic diagram of step S101 of the manufacturing method of a circuit board according to an embodiment of the present invention.

FIG. 1B is a schematic diagram of step S102 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1C is a schematic diagram of step S103 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1D is a schematic diagram of step S104 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1E is a schematic diagram of step S105 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1F is a schematic diagram of step S106 of the circuit board manufacturing method according to the embodiment of the present invention.

1G is a schematic diagram of step S107 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1H is a schematic diagram of step S108 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1I is a schematic diagram of step S109 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 1J is a schematic diagram of step S110 of the circuit board manufacturing method according to the embodiment of the present invention.

FIG. 2A is a schematic diagram of step S201 of the manufacturing method of the imprint mold according to the embodiment of the present invention.

FIG. 2B is a schematic diagram of step S202 of the manufacturing method of the imprint mold according to the embodiment of the present invention.

FIG. 2C is a schematic diagram of step S203 of the manufacturing method of the imprint mold according to the embodiment of the present invention.

FIG. 2D is a schematic diagram of step S204 of the manufacturing method of the imprint mold according to the embodiment of the present invention.

FIG. 3 is a schematic diagram of another variation of step S106 of the circuit board manufacturing method according to the embodiment of the present invention.

1: Insulating substrate

5: Metal lines

6: Dielectric layer film

M: Imprinting mold

M1: Soft film structure

M11: Soft film base material

M12:Protruding column structure

M2: Hard substrate

D: diameter

H: height

Claims (10)

A method of manufacturing a circuit board, which includes: Provide an insulating substrate and a metal circuit formed on the insulating substrate; Form a dielectric layer film on the metal lines, and make the dielectric layer film fall into the gap between the metal lines to contact the insulating substrate; An imprinting mold having a plurality of protruding pillar structures is covered on the dielectric layer film, and an imprinting operation is performed, so that the plurality of protruding pillar structures of the imprinting mold are pressed into the dielectric layer. layer film and in position corresponding to the metal lines; and The imprinting mold is removed from the dielectric layer film, so that the dielectric layer film has a plurality of imprinting pots whose shapes respectively correspond to the plurality of protruding pillar structures of the imprinting mold. hole. The manufacturing method of a circuit board according to claim 1, wherein the dielectric layer film is an ABF build-up film or an ABF-like build-up film, and the dielectric layer film is softened by vacuum hot pressing. , and fall into the gap between the metal lines. The manufacturing method of a circuit board according to claim 1, wherein in the imprinting operation, the dielectric layer film is heated to a softening temperature, and the hardness of the dielectric layer film is heated to The softening temperature is less than the hardness of the plurality of protruding pillar structures of the imprinting mold, so that the plurality of said protruding pillar structures of the said imprinting mold can be pressed into the said dielectric layer film. The manufacturing method of a circuit board according to claim 1, wherein the imprinting mold includes: a soft film structure and a hard substrate disposed on one side surface of the soft film structure; wherein the soft film structure has a soft film The base material and the plurality of protruding pillar structures protruding from one side surface of the soft film base material, and the hard substrate is disposed on the side surface of the soft film base material away from the plurality of said protruding pillar structures. to provide support to the soft membrane structure. The manufacturing method of a circuit board as claimed in claim 1, wherein the imprinting mold is formed by the following steps: A master mold is provided, which includes a hard mold base material and a plurality of protruding structures protruding from one side surface of the hard mold base material; Coating a soft film material on one side of the master mold having a plurality of the protruding structures to form a soft film structure on the master mold, which has a soft film base material and a plurality of the protruding pillar structures, And the plurality of protruding column structures of the soft film structure are geometrically complementary to the plurality of protruding structures of the master mold; A hard substrate is attached to a side surface of the soft film substrate away from the plurality of protruding column structures, thereby supporting the soft film structure; and the soft film structure and the hard substrate together constitute an imprinting mold; and The embossing mold is separated from the portion where the plurality of convex pillar structures of the soft film structure are connected to the plurality of convex structures of the master mold, thereby completing the preparation of the embossing mold. The manufacturing method of a circuit board according to claim 1, wherein each of the imprinted holes is recessed from a side surface of the dielectric layer film away from the insulating substrate toward the direction of the insulating substrate. Each of the stamped holes exposes at least part of the metal circuit to the external environment. The manufacturing method of a circuit board according to claim 1, wherein after forming a plurality of the imprinted holes on the dielectric layer film, the manufacturing method of the circuit board further includes: The dielectric layer film undergoes a heating and curing operation to change the dielectric layer film from a softened state to a cured state. The manufacturing method of a circuit board as claimed in claim 1, wherein the insulating substrate and the metal circuit are formed by the following steps: Provide the insulating substrate and a metal coating layer formed on the insulating substrate; A patterned photoresist mask is formed on the metal coating layer; wherein the photoresist mask is formed on a side surface of the metal coating layer away from the insulating substrate, and A plurality of gaps are formed on the inner side of the photoresist mask, and the portion of the metal coating layer that is not blocked by the photoresist mask is exposed to the plurality of gaps; A plurality of conductive metals are respectively formed in a plurality of the gaps; and The photoresist mask is removed, and a plurality of conductive metals are formed into the metal lines. A circuit board structure including: an insulating substrate; A metal circuit formed on the insulating substrate; A dielectric layer film is formed on the metal lines and falls into the gap between the metal lines to contact the insulating substrate; wherein the dielectric layer film has a shape corresponding to that of an imprinting mold. A plurality of embossed filling holes corresponding to the plurality of protruding pillar structures are filled with a plurality of conductive metals on the inside; Wherein, the dielectric layer film is an ABF build-up film or an ABF-like build-up film. The circuit board structure of claim 9, wherein the dielectric layer film has a material thickness ranging from 5 microns to 100 microns, a glass transition temperature (Tg) ranging from 150°C to 200°C, and a carbon dioxide The weight percentage of silicon is between 15wt% and 70wt%, a first thermal expansion coefficient (25~150°C) is between 10 ppm/°C and 40 ppm/°C, and a second thermal expansion coefficient (150~240°C) is between At 65 ppm/°C to 135 ppm/°C, a dielectric constant Dk (@5.8GHz) between 3 and 3.5, a tensile strength between 80 MPa and 120 MPa, and a Young's coefficient between 3 GPa to 10 GPa.