JP2011018893A - Insulation material, electronic element incorporation type printed board, and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulation material, an electronic element incorporation type printed board, and a method of manufacturing the same.SOLUTION: The method of manufacturing an electronic element incorporation type printed board includes steps of: providing a core board penetrated by a cavity and having a circuit pattern formed on a surface thereof; sticking an adhesive layer on the undersurface of the core board to cover the cavity; arranging an electronic element on an upper surface of the adhesive layer corresponding to the cavity; covering the circuit pattern by laminating a first insulation material without being impregnated with a reinforcing material on the upper surface of the core board to fill the cavity; and laminating a second insulation material impregnated with the reinforcing material on the upper and lower sides of the core board.

Description

  The present invention relates to an insulator, an electronic element-embedded printed circuit board, and a method for manufacturing an electronic element-embedded printed circuit board.

  With the development of the electronic industry, there is a tendency for electronic components to become highly functional and miniaturized. Especially, the movement of the market to make personal portable terminals lighter and thinner has led to thinner printed circuit boards. . Here, an element mounting method different from the conventional element mounting method has attracted attention, and an active component such as an IC or a passive component such as an MLCC type capacitor is used as a printed circuit board. This is an embedded printed circuit board that requires a higher density of components and an improvement in reliability by being mounted inside the package, or an improvement in the performance of the package itself by organic coupling of these components.

  The present invention is intended to solve the problems that arise from the incorporation of a high electronic component when a component-embedded substrate is manufactured. The problems are as follows.

  According to the prior art, when an electronic device (for example, MLCC: multilayer ceramic capacitor) having a height of 200 μm to less than 1000 μm is built in the core substrate, the adhesive layer 20 is used to form the cavity 14 as shown in FIG. After the electronic element 30 is built in the core substrate 10 on which the circuit 12 is formed, an insulator 40 in which a glass fiber 44 (Glass fabric) is impregnated with a resin 42 is laminated for the purpose of reducing warpage of the substrate. In this case, since the height of the electronic element 30 is high, the periphery of the electronic element and the via hole may not be completely filled with the insulating resin 42 as shown in FIG. That is, the void 50 is generated inside. This leads to poor reliability, and improvements to this are desired.

  In order to solve these problems, as shown in FIG. 3, a method using an insulator 40 ′ including a thick resin 42 ′ is proposed. This is because the printed circuit board is entirely formed as shown in FIG. Cause the problem of excessively thickening.

  In view of such problems of the prior art, the present invention prevents voids generated around the electronic element and between circuit patterns from the decrease in the resin content even when the lay-up process is performed using a thin insulator. An insulator, a printed circuit board with a built-in electronic element, and a method for manufacturing the same, which can solve the problem that the electronic element is damaged due to the reinforcing material impregnated in the insulator during the layup process The purpose is to provide.

  According to an embodiment of the present invention, a step of providing a core substrate that is penetrated by a cavity and provided with a circuit pattern on a surface thereof, and a step of attaching an adhesive layer to the lower surface of the core substrate so as to cover the cavity And a step of disposing an electronic element on the upper surface of the adhesive layer corresponding to the cavity, and laminating a first insulator not impregnated with a reinforcing material on the upper surface of the core substrate so as to fill the cavity. There is provided a method for manufacturing a printed circuit board with a built-in electronic element, comprising: a step of covering the circuit pattern; and a step of laminating a second insulator impregnated with a reinforcing material on the upper and lower sides of the core substrate. .

  According to another embodiment of the present invention, a core substrate that is penetrated by a cavity and provided with an inner layer circuit on a surface thereof, an electronic element that is built in the cavity, and that fills the cavity and includes the inner layer circuit. A first insulator that is laminated on the upper surface of the core substrate so as to cover and is not impregnated with a reinforcing material, and a second insulator that is laminated on the upper and lower sides of the core substrate and impregnated with a reinforcing material. And a printed circuit board with a built-in electronic element including the circuit pattern formed on the second insulator.

  At this time, the resin of the first insulator and the second insulator may be the same material.

  According to still another embodiment of the present invention, a step of providing a core substrate that is penetrated by a cavity and provided with a circuit pattern on a surface thereof, and a step of attaching an adhesive layer that covers the cavity to the lower surface of the core substrate. And a step of disposing an electronic device on the upper surface of the adhesive layer corresponding to the cavity, and an upper resin layer and a lower resin layer are formed vertically around the reinforcing material so as to fill the cavity. A step of laminating an insulator on the upper surface of the core substrate, wherein the insulator has an asymmetric shape in which the lower resin layer is thicker than the upper resin layer. A manufacturing method is provided.

  According to another embodiment of the present invention, the insulator is used for manufacturing a printed circuit board, and includes an upper resin layer and a lower resin layer respectively laminated on the upper and lower sides of the reinforcing material, and the lower resin An insulator is provided wherein the layer is thicker than the upper resin layer.

  Here, the thickness of the lower resin layer may be 2 to 5 times the thickness of the upper resin layer.

According to a preferred embodiment of the present invention, even when a lay-up process is performed using a thin insulator, it is possible to prevent voids generated around the electronic device and between circuit patterns due to a decrease in the resin content. it can. In addition, it is possible to solve the problem that the electronic element is damaged due to the reinforcing material impregnated in the insulator during the layup process.
It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

6 is a diagram illustrating a method for manufacturing a printed circuit board with a built-in electronic device according to the related art. 6 is a diagram illustrating a method for manufacturing a printed circuit board with a built-in electronic device according to the related art. 6 is a diagram illustrating a method for manufacturing a printed circuit board with a built-in electronic device according to the related art. 6 is a diagram illustrating a method for manufacturing a printed circuit board with a built-in electronic device according to the related art. FIG. 3 is a flowchart illustrating a method for manufacturing a printed circuit board with a built-in electronic element according to an embodiment of the present invention. 1 is a view illustrating a method of manufacturing an electronic device built-in type printed circuit board according to an embodiment of the present invention. 1 is a view illustrating a method of manufacturing an electronic device built-in type printed circuit board according to an embodiment of the present invention. 1 is a view illustrating a method of manufacturing an electronic device built-in type printed circuit board according to an embodiment of the present invention. 1 is a view illustrating a method of manufacturing an electronic device built-in type printed circuit board according to an embodiment of the present invention. 1 is a view illustrating a method of manufacturing an electronic device built-in type printed circuit board according to an embodiment of the present invention. FIG. 6 is a flow chart illustrating a method for manufacturing an electronic element built-in type printed circuit board according to another embodiment of the present invention. 6 is a view illustrating a method of manufacturing a printed circuit board with built-in electronic elements according to another embodiment of the present invention. 6 is a view illustrating a method of manufacturing a printed circuit board with built-in electronic elements according to another embodiment of the present invention. 6 is a view illustrating a method of manufacturing a printed circuit board with built-in electronic elements according to another embodiment of the present invention. 6 is a view illustrating a method of manufacturing a printed circuit board with built-in electronic elements according to another embodiment of the present invention. 6 is a view illustrating a method of manufacturing a printed circuit board with built-in electronic elements according to another embodiment of the present invention.

  Since the present invention can be modified in various ways and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail herein. However, this is not to be construed as limiting the invention to the specific embodiments, but is to be understood as including all transformations, equivalents, and alternatives falling within the spirit and scope of the invention.

  Hereinafter, an embodiment of a method of manufacturing an electronic element built-in type printed circuit board according to the present invention will be described in detail with reference to the accompanying drawings. In the description with reference to the accompanying drawings, the same and corresponding components are as follows. The same drawing number is attached and the duplicate description for this is omitted.

  FIG. 5 is a flowchart illustrating a method of manufacturing a printed circuit board with a built-in electronic device according to an embodiment of the present invention. FIGS. 6 to 10 illustrate a printed circuit with a built-in electronic device according to an embodiment of the present invention. It is drawing which shows the manufacturing method of a board | substrate.

  First, as shown in FIG. 6, after preparing the core substrate 110 penetrating by the cavity 114 and having the inner layer circuit 112 provided on the surface in step S110, the cavity 114 is covered on the lower surface of the core substrate 110 in step S120. Then, the adhesive layer 120 is attached. As the core substrate 110, a copper clad laminate (CCL) can be used, and in addition, an epoxy resin impregnated with glass fibers can be used to reinforce the rigidity. An inner layer circuit 112 is provided on the surface of the core substrate 110.

  When a copper clad laminate is used as the core substrate 110, in order to form the inner layer circuit 112 on the surface, a circuit pattern is formed by selective electroplating after forming a seed layer by electroless plating on both sides of the copper clad laminate. The method of forming can be used. In addition, a method of forming the inner layer circuit 112 by etching a part of the copper foil formed on both surfaces of the copper clad laminate can be used.

  A cavity 114 is processed at a predetermined position (for example, a central portion) of the core substrate 110. The cavity 114 is a space in which the electronic element 140 is built, and can be formed by a processing method using a mechanical drill or a laser drill. The lower side of the cavity 114 thus processed is shielded by the adhesive layer 120.

  Next, in step S130, the electronic element 140 is disposed on the upper surface of the adhesive layer 120 corresponding to the cavity 114, as shown in FIG. When the electronic element 140 is arranged in this way, the electronic element 140 is attached and fixed to the upper surface of the adhesive layer 120 exposed to the cavity 114.

  Thereafter, in step S140, as shown in FIGS. 6 and 7, the inner layer circuit 112 is formed by laminating the first insulator 130 that is not impregnated with the reinforcing material on the upper surface of the core substrate 110 so that the cavity 114 is filled. Cover.

  When the first insulator 130 (for example, a primer resin) that is not impregnated with the reinforcing material is laminated on the upper surface of the core substrate 110 having the inner layer circuit 112 formed on the surface in this manner, a flat surface is formed on the upper portion. The remaining space of the cavity 114 is filled with the 1 insulator 130, and not only the electronic element 140 can be fixed, but also the inside of the via hole is filled with the first insulator 130.

  Further, the inner layer circuit 112 formed on the upper surface of the core substrate 110 is covered with a first insulator 130. Further, when all the electrodes (not shown) of the electronic element 140 are arranged upward, that is, when the electronic element 140 is built in a face-up manner, the electrodes (not shown) of the electronic element 140 are arranged. ) Is also covered with resin.

  Thus, before the lay-up process using the second insulator 150 (see FIG. 9) impregnated with the reinforcing material for ensuring rigidity, another first insulator 130 not impregnated with the reinforcing material is used. Is stacked on the core substrate 110, so that the remaining space of the cavity 114, the space inside the via hole, the space between the circuit patterns 112, and the space between the circuit pattern 112 and the electrodes of the electronic element 140 can be filled. Even when the thin second insulator 150 having a low resin content is stacked, the space between the cavity 114, the via hole, the circuit pattern 112, and the circuit pattern 112 and the electrode (not shown) of the electronic element 140 is also used. It is possible to prevent the generation of voids.

  Thereafter, in step S150, the adhesive layer 120 is removed as shown in FIG. 8, and in step S160, the second insulator 150 in which the reinforcing material 154 is impregnated on the upper and lower sides of the core substrate 110 as shown in FIG. Are laminated. At this time, the resin 152 of the second insulator 150 may be made of the same material as that of the first insulator 130 described above. That is, the second insulator 150 including the same material as the first insulator 130 used for filling the cavity 114 and the via hole may be used. By using an insulator including the same material as described above, it is possible to reduce the possibility of warpage due to a difference in thermal expansion coefficient at the interface between the first insulator 130 and the second insulator 150. Further, it is possible to secure a strong adhesive force between them. As a result, the problem of interlayer delamination can be solved.

  In addition, since the first insulator 130 fills all of the inside of the cavity 114, the inside of the via hole, the gap between the circuit patterns 112, etc., the thin second insulator 150 having a low resin 152 content without generating voids. The printed circuit board can be made thinner. Furthermore, since the first insulator 130 that has already been formed exhibits a buffering function between the reinforcing material 154 impregnated in the second insulator 150 and the electrode and / or circuit pattern 112 of the electronic element 140, the impregnation is performed. It is possible to eliminate the damage of the electronic element 140 and / or the circuit pattern 112 due to the reinforcing member 154 in contact with the electrode (not shown) and / or the circuit pattern 112 of the electronic element 140.

  Next, as shown in FIG. 10, another circuit pattern 162 is formed on the upper surface of the second insulator 150. The circuit pattern 162 formed on the upper surface of the second insulator 150 can be protected by a solder resist 160 as shown in FIG. Needless to say, when a printed circuit board having a higher number of layers is to be manufactured, the lay-up process may be further performed without forming the solder resist 160.

  FIG. 11 is a flowchart illustrating a method of manufacturing a printed circuit board with a built-in electronic device according to another embodiment of the present invention. FIGS. 12 to 16 illustrate a printed circuit with a built-in electronic device according to another embodiment of the present invention. It is drawing which shows the manufacturing method of a circuit board.

  First, in step S210, as shown in FIG. 12, the core substrate 110 penetrating through the cavity 114 and having the inner layer circuit 112 provided on the surface is prepared. In step S220, the cavity 114 is covered on the lower surface of the core substrate 110. The adhesive layer 120 is attached as described above. As the core substrate 110, a copper clad laminate (CCL) can be used, and in addition, an epoxy resin impregnated with glass fibers can be used to reinforce the rigidity. An inner layer circuit 112 is provided on the surface of the core substrate 110.

  When a copper clad laminate is used as the core substrate 110, a circuit pattern is formed by selective electroplating after forming a seed layer by electroless plating on both sides of the copper clad laminate to form an inner layer circuit 112 on the surface of the core substrate 110. Can be used. In addition, a method of forming the inner layer circuit 112 by etching a part of the copper foil formed on both surfaces of the copper clad laminate can be used.

  A cavity 114 is processed at a predetermined position (for example, the central portion) of the core substrate 110. The cavity 114 is a space in which the electronic element 140 is built, and can be formed by a processing method using a mechanical drill or a laser drill. The lower side of the cavity 114 thus processed is shielded by the adhesive layer 120.

  Thereafter, in step S230, the electronic element 140 is disposed on the upper surface of the adhesive layer 120 corresponding to the cavity 114, as shown in FIG. When the electronic element 140 is arranged in this way, the electronic element 140 is attached and fixed to the upper surface of the adhesive layer 120 exposed to the cavity 114.

  Thereafter, in step S240, as shown in FIG. 13 and FIG. 14, the first insulator in which the upper resin layer 236 and the lower resin layer 234 are formed in the vertical direction around the reinforcing material 232 so as to fill the cavity. 230 is stacked on the upper surface of the core substrate 110. At this time, the first insulator 230 stacked on the upper surface of the core substrate 110 has an asymmetric shape in which the lower resin layer 234 is thicker than the upper resin layer 236.

  When the first insulator 230 having a structure in which the lower resin layer 234 is thicker than the upper resin layer 236 is laminated on the upper surface of the core substrate 110 having the inner layer circuit 112 formed on the surface in this manner, a relatively thick lower resin layer is formed. In 234, the remaining space of the cavity 114 is filled, and not only the electronic element 140 can be fixed, but also the inside of the via hole is filled with the lower resin layer 234. Further, the inner layer circuit 112 formed on the upper surface of the core substrate 110 is covered with the lower resin layer 234.

  Further, when all the electrodes (not shown) of the electronic element 140 are arranged upward, that is, when the electronic element 140 is built up in a face-up manner, the electrode (not shown) of the electronic element 140 is also a lower resin layer. 234.

  Thus, by using the first insulator 230 having an asymmetric structure in which the lower resin layer 234 is thicker than the upper resin layer 236, the remaining space inside the cavity 114, the space inside the via hole, the space between the inner layer circuits 112, the inner layer The space between the circuit 112 and the electrode of the electronic element 140 is all filled, and the space between the cavity 114, the via hole, the inner layer circuit 112, the inner layer circuit 112 and the electrode of the electronic element 140 (not shown). It is possible to prevent voids from occurring in the space between.

  At this time, the thickness of the lower resin layer 234 is preferably 2 to 5 times the thickness of the upper resin layer 236. If the lower resin layer has a thickness twice to five times that of the upper resin layer, voids due to insufficient resin can be more effectively prevented, and the printed circuit board becomes excessively thick overall. Can be prevented.

  Next, in step S250, the adhesive layer 120 is removed as shown in FIG. 15, and in step S260, a second insulator 230 'is stacked on the lower side of the core substrate 110 as shown in FIG. At this time, the second insulator 230 'may or may not be impregnated with a reinforcing material 232' such as glass fiber. As shown in FIG. 16, when the reinforcing material 232 ′ is impregnated, the thicknesses of the resin layers 234 ′ and 236 ′ laminated on both surfaces of the reinforcing material may be the same as each other, and may differ depending on necessity. Also good.

  Thereafter, as shown in FIG. 16, a circuit pattern 162 is formed on the surface of the first insulator 230 and the surface of the second insulator 230 '. The circuit pattern 162 formed on the surface of the first insulator 230 and the surface of the second insulator can be protected by the solder resist 160. Needless to say, when a printed circuit board having a higher number of layers is to be manufactured, the lay-up process may be further performed without forming the solder resist 160.

  Here, the manufacturing method of the insulator, the electronic element built-in type printed circuit board, and the electronic element built-in type printed circuit board according to the present embodiment includes, for example, a step of providing a core substrate and a step of attaching an adhesive layer This is performed by driving a drive control unit (not shown). A CPU (not shown) reads a program from a memory (not shown) in which a program (command) such as a process order of each process is stored, and transmits a control signal to the drive control unit (not shown). Thus, each process is executed.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

110 Core substrate 120 Adhesive layer 130, 230 First insulator 140 Electronic element 150 Second insulator 154 Reinforcing material

Claims (8)

Providing a core substrate penetrated by the cavity and provided with a circuit pattern on the surface;
Attaching an adhesive layer to cover the cavity on the lower surface of the core substrate;
Disposing an electronic element on the upper surface of the adhesive layer corresponding to the cavity;
Stacking a first insulator that is not impregnated with a reinforcing material on an upper surface of the core substrate so as to fill the cavity, and covering the circuit pattern;
Laminating a second insulator impregnated with a reinforcing material on the upper and lower sides of the core substrate;
The manufacturing method of the printed circuit board with a built-in electronic element characterized by including these.   The method of manufacturing a printed circuit board with built-in electronic elements according to claim 1, wherein the resin of the first insulator and the second insulator are made of the same material. A core substrate penetrated by a cavity and provided with an inner layer circuit on its surface;
An electronic element built in the cavity;
A first insulator that is laminated on an upper surface of the core substrate so as to fill the cavity and cover the inner layer circuit, and is not impregnated with a reinforcing material;
A second insulator that is respectively laminated on the upper and lower sides of the core substrate and impregnated with a reinforcing material;
A circuit pattern formed on the second insulator;
A printed circuit board with a built-in electronic element, comprising:   The printed circuit board with built-in electronic elements according to claim 3, wherein the resin of the first insulator and the second insulator are made of the same material. Providing a core substrate penetrated by the cavity and provided with a circuit pattern on the surface;
Attaching an adhesive layer covering the cavity to the lower surface of the core substrate;
Disposing an electronic element on the upper surface of the adhesive layer corresponding to the cavity;
Laminating an insulator in which an upper resin layer and a lower resin layer are formed on the upper and lower sides around a reinforcing material so as to fill the cavity, respectively, on the upper surface of the core substrate,
The method of manufacturing a printed circuit board with built-in electronic elements, wherein the insulator has an asymmetric shape in which the lower resin layer is thicker than the upper resin layer.   6. The method of manufacturing a printed circuit board with built-in electronic elements according to claim 5, wherein the thickness of the lower resin layer is 2 to 5 times the thickness of the upper resin layer. An insulator used in the manufacture of printed circuit boards,
Including an upper resin layer and a lower resin layer respectively laminated on the top and bottom of the reinforcing material,
The insulator, wherein the lower resin layer is thicker than the upper resin layer.   The insulator according to claim 7, wherein the thickness of the lower resin layer is 2 to 5 times the thickness of the upper resin layer.

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