TW201417656A - Manufacturing method of circuit-component built-in substrate - Google Patents

Abstract

The present invention provides a manufacturing method of a circuit-component built-in substrate using a prepreg material utilizing epoxy resin as the main ingredient and having electrical connection reliability. The method comprises: a circuit component installation step that forms one or more than one through holes in the direction of the thickness of a first insulation substrate material, and inserting circuit components into all or a part of through holes to make both the electrode terminals above or below it are orientated toward the thickness direction; an internal through hole formation step that forms one or more than one first through holes in the direction of the thickness of a second insulation substrate material and fills a first conductive composition into the first through hole(s) to form the first internal through holes for electrical connection; and a laminate pressing/heating step that allocates the second insulation substrate material with the first internal through hole(s) to both sides of the first insulation substrate material with inserted circuit component, and furthermore allocates and laminates wiring elements at the outer lateral surface of the second insulation substrate material and proceeds with pressing and heating.

Description

Method for manufacturing built-in substrate of circuit component Technical field

The present invention relates to a method of fabricating a substrate embedded in a circuit component.

Background technique

In recent years, with the miniaturization of electronic machines. The demand for high-density mounting of electronic components mounted on a printed circuit board and high performance of a circuit board on which an electronic component is mounted is increasing with the increase in thickness and performance. In such a case, a substrate is embedded in a circuit component in which an electronic component is filled in a substrate.

The circuit component houses a substrate. Usually, an active component (for example, a semiconductor component) or a passive component (for example, a resistor or a capacitor) mounted on the surface of the printed substrate is filled in the substrate, so that the substrate area can be reduced. Further, since the degree of freedom in arranging circuit elements can be improved as compared with the surface mounting, it is also expected to improve the high-frequency characteristics and the like by optimizing the wiring between the circuit elements.

A method of manufacturing a substrate in which a circuit component can be easily filled in a circuit component, and a method of forming an existing electrical circuit between the plurality of printed circuit boards on which a circuit component is preliminarily mounted is provided. The insulating sheet of the through hole is electrically connected and integrated by pressure heat treatment (for example, refer to Patent Document 1). In this manufacturing method, the multilayer substrate can be easily fabricated without the need of wet processing such as etching or plating.

Further, in order to increase the built-in density of the element, an insulating sheet in which a pre-built component is longitudinally filled in the thickness direction between the multilayer printed boards and integrated by pressure heating treatment has been proposed. (For example, refer to Patent Document 2).

Next, a method of manufacturing the circuit element-embedded substrate disclosed in Patent Document 2 will be described with reference to FIGS. 8(a) to 8(i). (a) to (i) of FIG. 8 are cross-sectional structural views for explaining respective steps of a method of manufacturing a conventional circuit element-embedded substrate described in Patent Document 2.

First, as shown in FIG. 8(a), a film 201 is attached to both surfaces of a composite sheet 202 constructed of a mixture of an uncured thermosetting resin and an inorganic filler. Next, as shown in FIG. 8(b), a through hole 203 for inserting the circuit element in the longitudinal direction with respect to the thickness direction of the composite board 202 and a through hole 204 for forming the inner through hole are formed.

Then, as shown in FIG. 8(c), the circuit component 206 is inserted longitudinally in the through hole 203, and as shown in FIG. 8(d), the through hole 203 is shrunk by heat treatment to block the composite board 202 and the circuit component 206. The gap between them. Next, as shown in FIGS. 8(e) and 8(f), the conductive composition 205a is filled by printing on both sides of the via hole 204 and the electrode terminal portion of the circuit element 206. Then, as shown in FIG. 8(g), the conductive composition 205a is dried by post-heating treatment, and then the film 201 is peeled off.

And, as shown in FIG. 8(h), the circuit component 206 is filled in and The two main faces of the composite plate 221 having the inner through holes 205b are formed, and are laminated and formed with a multilayer printed substrate 231 having a via land 232 electrically connected to the inner through holes 205b, as shown in Fig. 8(i). As shown in the figure, the circuit board built-in substrate 241 is manufactured by integration by pressure heat treatment.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2003-197849

Patent Document 2: Japanese Patent Laid-Open No. 2011-204811

Summary of invention

However, in the above-described conventional manufacturing method, a low-cost prepreg or the like of a general-purpose material cannot be used as a substrate of a built-in circuit element.

The reason will be explained below.

9(a) to 9(c) are a partial plan view and a cross-sectional structural view showing respective steps of a method of manufacturing a circuit element-embedded substrate described in Patent Document 2.

Fig. 9(a) is a partial plan view and a cross-sectional structural view showing the insertion of the circuit component 206 into the through hole 203 as shown in Fig. 8(c). Fig. 9(b) is a partial plan view and a cross-sectional structural view showing a state in which the through hole 203 is contracted by heat treatment as shown in Fig. 8(d). Fig. 9(c) is a partial plan view and a cross-sectional structural view showing a state in which the conductive composition 205a is filled by printing as shown in Figs. 8(e) and 8(f).

In the above conventional manufacturing method, as shown in FIG. 9(a), in formation After the circuit element 206 is inserted into the through hole 203 of the composite board 202, as shown in FIG. 9(b), the through hole 203 is shrunk by heat treatment to block the gap between the composite board 202 and the circuit component 206. By blocking the gap between the composite board 202 and the circuit component 206, as shown in FIG. 9(c), even if the electrode terminal portion of the circuit component 206 is filled with the conductive composition 205a, the occurrence of a short circuit can be prevented. Here, in order to obtain the shrinkage effect of the through hole 203 by the heat treatment of FIG. 9(b), it is necessary to punch the through hole 203 with a punch to leave a processing strain or a rubber component such as acrylic rubber as a material of the composite sheet 202. structure.

The composite panel 202 used herein is a custom material and is costly.

In the method of manufacturing the circuit element-embedded substrate described in Patent Document 2, a prepreg using a common substrate material, that is, a thermosetting epoxy resin as a main component, is used in the method of manufacturing the circuit element-embedded substrate described in Patent Document 2 (a) to (c). 302 is a partial plan view and a cross-sectional structural view of each step when the composite plate 202 is used. The steps of Figs. 10(a) to 10(c) show the steps corresponding to Figs. 9(a) to 9(c), respectively.

At this time, as shown in FIG. 10(a), after the circuit element 206 is inserted into the through hole 203 in which the prepreg 302 is formed, as shown in FIG. 10(b), the through hole 203 is not shrunk even if the heat treatment is performed. Therefore, when the conductive composition 205a is printed on the electrode terminal portion of the circuit component 206, as shown in FIG. 10(c), the paste-like conductive composition 205a enters the gap between the prepreg 302 and the circuit component 206. This causes a short circuit between the electrode terminals of the circuit component 206.

Further, in this manufacturing method, since the electrode terminal portion of the circuit element 206 is required to be printed with the paste-like conductive composition 205a from both sides, the paste which has been filled on the surface side when filling the back side is easily attached after filling the surface side. a support for placing the composite panel (generally, a liner is placed on the substrate) Etc. There are also problems such as difficulty in handling steps.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the invention is to provide a method for producing a circuit element-embedded substrate which is improved in electrical connection reliability by using a prepreg which is a thermosetting epoxy resin as a main component.

In order to achieve the above object, a method of manufacturing a circuit element-embedded substrate according to a first aspect of the present invention includes the step of mounting a circuit element, wherein one or a plurality of through holes are formed in a thickness direction of a material of the first insulating substrate, and all or a part thereof The through hole is inserted into the circuit element, and the upper and lower electrode terminals are formed in the thickness direction to form an inner through hole, and one or a plurality of first through holes are formed in the thickness direction of the material of the second insulating substrate, and the first through hole is formed. The through hole is filled with the first conductive composition, and the first inner via hole for electrical connection and the laminated pressure heating step are formed, and the first insulating substrate on which the circuit element is inserted is disposed on both surfaces of the material. The material of the second insulating substrate of the first inner via hole is disposed on the outer surface of the material of the second insulating substrate, and the wiring member is laminated and pressurized, and the substrate is pressurized and heated. The electrode terminal of the element and the first inner via are disposed at respective positions, and the first inner via and the electrode terminal formed on the wiring element are disposed Respectively corresponding to the position.

Further, a method of manufacturing a circuit element-embedded substrate according to a second aspect of the invention is the method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, wherein in the step of mounting a circuit element, one or a plurality of the through holes are formed, all Before the through hole of the portion or a part of the through hole is inserted into the circuit component, a film for blocking the opening of the through hole is attached to the first insulating substrate, and the thickness of the material of the first insulating substrate is the same as the film. One or a plurality of second via holes are formed in the second via hole, and the second conductive via is filled in the second via hole to form a second inner via hole for electrical connection.

In the method of manufacturing a circuit element-embedded substrate according to the second aspect of the invention, the first insulating substrate is a prepreg containing epoxy resin as a main component.

Further, in the method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, the method of manufacturing the circuit element-embedded substrate according to the first aspect of the invention, wherein the step of mounting the circuit element forms one or a plurality of the through holes, The circuit element is inserted into the through hole, and a conductive element having a predetermined shape is inserted into one of the through holes.

Further, in the method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, the method of manufacturing the circuit element-embedded substrate according to the first aspect of the invention, wherein a thickness of a material of the first insulating substrate is a length of the circuit element included in the circuit element -0.2mm or more and +0.08mm or less.

In the method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, the material of the second insulating substrate is 0.03 mm or more and 0.2 mm or less.

In the method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, the electrode terminal of the circuit element is rectangular and formed on the second insulating substrate. The diameter of the first through hole of the material is 0.03 mm or more and 0.3 mm or less. Further, the diagonal length of the electrode terminal of the circuit element is equal to or less.

In the method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, the wiring device is a multilayer printed circuit board.

According to the present invention, it is possible to provide a method for producing a circuit element-embedded substrate which is improved in electrical connection reliability by using a prepreg or the like which is a thermosetting epoxy resin as a main component.

101a, 101b, 111, 201‧‧ ‧ film

102,112,302‧‧‧Prepreg

202,221‧‧‧Composite board

103,203‧‧‧through holes

104,113,204‧‧‧through hole

105a, 115a, 205a‧‧‧ Conductive composition

105b, 115b, 205b‧‧‧ through hole

106,206‧‧‧ circuit components

107‧‧‧Electrical components

131‧‧‧Wiring components

132‧‧‧electrode terminal

141,142,241‧‧‧ Built-in substrate for circuit components

231‧‧‧Printed substrate

232‧‧‧through hole area

A1, A2, B1, B2‧‧‧ bulging

121,123‧‧‧Insert substrate A

122‧‧‧Insert substrate B

C1, C2‧‧‧ thickness

L1, L2, L3‧‧‧ diameter

Fig. 1 (1) shows the steps (the steps of manufacturing the insulating substrate A) (a) to (f) (the step of attaching the film, the step of forming the through hole, the step of reattaching the film, the step of forming the through hole, the filling, heating) A cross-sectional structural view of a manufacturing step of the insulating substrate A in each step of the manufacturing method of the circuit element according to the first embodiment of the present invention, in which the conductive composition is processed, and the film is removed.

Fig. 1 (2) shows the steps of (manufacturing the insulating substrate B) (g) to (j) (the step of attaching the film, forming the through hole, filling, heating the conductive composition, and peeling the film) A cross-sectional structural view of a manufacturing step of the insulating substrate B in each step of the manufacturing method of the circuit element according to the first embodiment of the present invention.

Fig. 1 (3) shows the steps of the manufacturing method of the circuit element according to the first embodiment of the present invention for explaining (layering integration step) (k), (m) (layering step, pressure heating treatment step) A cross-sectional structural view of a manufacturing step of laminating the integrated insulating substrate A, the insulating substrate B, and the wiring member.

Fig. 2 (a) is a partial cross-sectional structural view showing a structure in which a circuit element protrudes from a prepreg in a lamination step of a method of manufacturing a circuit element-embedded substrate according to Embodiment 1 of the present invention.

Fig. 2 (b) is a partial cross-sectional structural view showing a structure in which a circuit element is recessed from a prepreg material in a lamination step of a method of manufacturing a circuit element-embedded substrate according to Embodiment 1 of the present invention.

Fig. 3 (a) is a partial cross-sectional structure of a circuit element-embedded substrate after being subjected to pressure heat treatment in a laminated state in which a prepreg material is protruded in a method of manufacturing a circuit element-embedded substrate according to a first embodiment of the present invention; Figure.

Fig. 3 (b) is a partial cross-sectional structural view of a circuit element-embedded substrate in a state in which a circuit element is laminated in a state in which a prepreg material is recessed in a laminated state in a method of manufacturing a circuit element-embedded substrate according to a first embodiment of the present invention; .

4(a) to 4(c) are the insulation before and after peeling off the film when the diameters of the through holes of the insulating substrate B are different from each other in the method of manufacturing the circuit element-embedded substrate according to the first embodiment of the present invention. A partial cross-sectional structural view of the substrate B.

In the method of manufacturing a circuit element-embedded substrate according to the first embodiment of the present invention, the diameter of the through hole formed in the insulating substrate B is set to be smaller than the diameter of the electrode terminal of the wiring member. A cross-sectional structural view of the substrate.

In the method of manufacturing a circuit element-embedded substrate according to the first embodiment of the present invention, the diameter of the through hole formed in the insulating substrate B is set to be larger than the diameter of the electrode terminal of the wiring member. A cross-sectional structural view of the substrate.

Figure 6 (1) is shown to illustrate (manufacture of insulating substrate A step (a) to (c) (steps of forming a through hole, inserting a circuit element, and inserting a conductive element), manufacturing steps of the insulating substrate A in each step of the manufacturing method of the circuit element according to the second embodiment of the present invention Sectional construction diagram.

Fig. 6 (2) shows the steps (the steps of manufacturing the insulating substrate B) (d) to (g) (the film coating step, the through hole forming step, the conductive composition filling, the heat treatment step, and the film peeling step) A cross-sectional structural view of a manufacturing step of the insulating substrate B in each step of the manufacturing method of the circuit element according to the second embodiment of the present invention.

Fig. 6 (3) shows the steps of the manufacturing method of the circuit element according to the second embodiment of the present invention for explaining (layering integration step) (h), (i) (layering step, pressure heating treatment step) A cross-sectional structural view of a manufacturing step of laminating the integrated insulating substrate A, the insulating substrate B, and the wiring member.

Fig. 7 is a partial cross-sectional photograph of a substrate in which a circuit element is fabricated by using the manufacturing method of the first or second embodiment of the present invention.

8(a) to 8(i) are for explaining (attach film coating step, forming through hole, through hole step, inserting circuit element step, heat treatment 1 step, filling conductive composition step, filling conductivity) Composition (inside) step, heat treatment 2. Stripping coating step, laminating step, and pressure heating treatment step) A cross-sectional structural view of each step of a conventional method for manufacturing a circuit element-embedded substrate.

9(a) to 9(c) are a partial plan view and a cross-sectional structural view showing respective steps of a method of manufacturing a conventional circuit element-embedded substrate.

10(a) to 10(c) show a partial plan view of each step in a method of manufacturing a substrate in which a circuit element is embedded, using a prepreg containing a thermosetting epoxy resin as a main component as a composite sheet. And sectional structure diagram.

Form for implementing the invention

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)

1(1)((a)~(f)), Fig. 1(2)((g)~(j)), Fig. 1(3)((k) and (m)) are used to illustrate the present invention A cross-sectional structural view of each step of the method of manufacturing the circuit element-embedded substrate of the first embodiment.

Fig. 1 (1) ((a) to (f)) show the manufacturing steps of the insulating substrate A showing the built-in circuit components, and Fig. 1 (2) ((g) to (j)) are shown to form circuit components. The manufacturing process of the insulating substrate B of the electrode terminal and the inner via hole of the electrode terminal of the wiring element, and FIG. 1 (3) ((k) and (m)) show the laminated integrated insulating substrate A, the insulating substrate B, and the wiring component Manufacturing steps.

First, the manufacturing steps of the insulating substrate A shown in Fig. 1 (1) ((a) to (f)) will be described.

In Fig. 1 (1) (a) of the manufacturing step of the insulating substrate A, for example, a general-purpose printing material, that is, a prepreg material can be used as the electrically insulating substrate material. Hereinafter, the prepreg 102 will be described as an insulating substrate material as an example.

In general, the prepreg is formed into a sheet form by using a glass cloth material and a thermosetting resin of a resin component as a main component, and by processing a mixture containing an inorganic filler as needed. The prepreg can be formed into a certain thickness by applying a thermosetting resin to a glass cloth material having a selected diameter and a mesh thickness depending on desired characteristics.

In the first embodiment, an epoxy resin (weight ratio: 55%) is applied to a glass cloth (model 2116), and a prepreg having a thickness of about 0.14 mm and four sheets of glass cloth (model number 1080) are formed. An epoxy resin (70% by weight) was applied and formed into a prepreg having a thickness of about 0.1 mm to prepare a prepreg 102 having a total thickness of 0.54 mm.

In the first embodiment, the wafer resistance of the built-in circuit element size of 0.6 × 0.3 mm is estimated, and the thickness of the prepreg 102 is set. However, the thickness of the prepreg 102 can be changed in accordance with the type of the built-in component. For example, in the case of a wafer element having a size of 0.4 × 0.2 mm, the total thickness of the prepreg material 102 can be set to 0.34 mm (one prepreg having a thickness of 0.14 mm and two prepreg having a thickness of 0.1 mm).

In the first embodiment, in the step of attaching the film of Fig. 1 (1) (a), a plurality of prepreg materials are stacked in accordance with the desired thickness, and a film 101a having a thickness of 0.02 mm is disposed on the outer surface thereof. The laminate was integrated by vacuum lamination at a temperature of 80 ° C, a pressure of 0.5 MPa, and a time of 1 minute. By applying a temperature of 80 ° C to soften the epoxy resin component of the prepreg, the prepreg material group and the film 101a can be subsequently integrated. As the film 101a, for example, a film of polyethylene terephthalate or polyphenylene sulfide can be used.

Further, in order to suppress a small thermal expansion coefficient, an inorganic filler such as cerium oxide particles may be added to the epoxy resin. Further, in addition to the epoxy resin, a phenol resin or an isocyanate resin having high heat resistance can also be used. Further, by using a fluororesin having a dielectric loss tangent low, for example, a polytetrafluoroethylene (PTFE resin), a PPO (polyphenylene ether) resin, or a resin containing a liquid crystal polymer or modifying the resin, the electricity can be increased. High frequency characteristics of the insulating layer. Also, you can The structure containing glass cloth.

Thereafter, as shown in Fig. 1 (1) and (b), a through hole 103 having a diameter of 0.37 mm is formed at a position where the circuit component 106 is desired to be disposed. The through hole 103 can be formed by, for example, drilling processing, laser processing, or mold processing using a punching machine. The method of forming the through-holes 103 in the prepreg 102 having a thickness and a glass cloth as a core material is preferably performed by drilling. Further, the diameter of the through hole 103 is set to correspond to the diagonal length dimension of the electrode terminal portion of the built-in circuit component 106.

Thereafter, as shown in Fig. 1 (1) and (c), the upper portion of the through hole 103 is blocked, so that the conductive composition 105a does not enter the through hole 103 in the subsequent step.

In the first embodiment, after the film 101a is peeled off, the film 101b is re-applied by vacuum lamination in the same manner as the step of attaching the film of Fig. 1 (1) and (a).

Further, the film 101b to be reattached is an example of a film which blocks the opening of the through hole of the present invention.

Further, the through film 103 may be blocked by laminating the film 101a without being peeled off. At this time, since the film on the upper side of the two sheets is superposed, a thin film can be used as the film.

Thereafter, as shown in Fig. 1 (1) and (d), the through hole 104 is formed at a position where the inner through hole 105b is desired to be formed. The processing method is the same as that of the through hole 103, and the diameter of the through hole 104 is 0.2 mm.

Thereafter, as shown in FIG. 1 (1) and (e), the conductive composition 105a is filled in the via hole 104.

As the conductive composition 105a, for example, a conductive resin composition in which metal particles and a thermosetting resin are mixed can be used. As the metal particles, gold, silver, copper, nickel, or the like can be used. Gold, silver, copper or nickel is preferred because of its high conductivity, and copper is less conductive due to its conductivity. The use of silver-coated copper metal particles also satisfies two characteristics of less migration and high conductivity. As the thermosetting resin, for example, an epoxy resin, a phenol resin or an isocyanate resin can be used. Epoxy resins are particularly excellent in heat resistance.

Further, the conductive composition 105a may be metal-bonded using a material containing solder.

In the filling of the conductive composition 105a, the prepreg 102 having the through holes 104 is placed on a stage of a printing machine (not shown), and the conductive composition 105a is directly filled from the film 101b by printing. At this time, the upper film 101b functions as a printing mask and prevents the surface of the prepreg 102 from being contaminated.

In the step of (1) and (e), after the conductive composition 105a is filled, heat treatment is performed at 80 ° C for about 30 minutes, and the conductive composition 105a is dried and pillared to form the inner via hole 105b.

Further, the through hole 104 is an example of the second through hole of the present invention, and the conductive composition 105a is an example of the second conductive composition of the present invention. Further, the inner through hole 105b is an example of the second inner through hole of the present invention.

Thereafter, as shown in FIGS. 1 (1) and (f), after the films 101a and 101b are peeled off, the circuit component 106 is inserted into the through hole 103 in the longitudinal direction. At this time, since the inner through hole 105b is pillared by heat treatment, there is no problem in protruding from the surface of the prepreg material 102. Further, after the circuit component 106 is inserted, the films 101a and 101b can be peeled off.

By the above steps, the insulating substrate A121 in which the circuit component 106 is disposed longitudinally with respect to the thickness direction and the inner via hole 105b is formed can be manufactured.

Further, the insulating substrate A121 is an example of the first insulating substrate of the present invention, and the prepreg 102 is an example of the first insulating substrate material of the present invention.

Further, the steps shown in Figs. 1(1)(b) to 1(1)(f) are examples of the steps of mounting the circuit elements of the present invention.

Next, a manufacturing procedure of the insulating substrate B shown in Fig. 1 (2) ((g) to (j)) will be described. The insulating substrate B is manufactured by the same manufacturing method as the insulating substrate A.

Fig. 1 (2) (g) is a step of attaching a film. The thickness of the prepreg 112 was 0.14 mm, and one piece of epoxy resin (weight ratio: 55%) was applied to a glass cloth (model 2116) to form a thickness of about 0.14 mm. A film 111 having a thickness of 0.02 mm was attached to the two main faces of the prepreg 112 by vacuum lamination.

Fig. 1 (2) (h) is a step of forming a through hole. A through hole 113 having a diameter of 0.15 mm is processed by drilling, laser processing or the like at a position where it is desired to form the inner through hole 115b.

Fig. 1 (2) (i) is a step of filling a conductive composition and a heat treatment step. The conductive composition 115a is filled by printing on the through hole 113. Thereafter, the conductive composition 115a is pillared by heat treatment to form an inner via hole 115b.

Fig. 1 (2) (j) is a step of peeling off the film. By removing the film 111 by peeling, the insulating substrate B122 in which the inner via hole 115b is formed can be manufactured.

In addition, the insulating substrate B122 is one of the second insulating substrates of the present invention. For example, the prepreg 112 is an example of a material of the second insulating substrate of the present invention. Further, the through hole 113 is an example of the first through hole of the present invention. Further, the conductive composition 115a is an example of the first conductive composition of the present invention, and the inner through hole 115b is an example of the first inner through hole of the present invention.

Further, the steps shown in Figs. 1(2)(h) to 1(2)(j) are examples of the steps of forming the inner through hole in the present invention.

Next, the step of integrating the layers shown in Fig. 1 (3) ((k) and (m)) will be described.

As shown in Fig. 1 (3) and (k), the insulating substrate B122 is placed on both main surfaces of the insulating substrate A121, and the wiring member 131 is placed on the outer surface of the insulating substrate B122 to be laminated. At this time, at the time of lamination, the electrode terminal and the inner via hole 105b of the circuit element 106 formed on the insulating substrate A121, the via hole 115b formed in the insulating substrate B122, and the electrode terminal 132 of the wiring member 131 (for example, a diameter of 0.3 mm) The through hole area is aligned at the time of lamination and placed on the same coordinate. The method of laminating the layers can be easily aligned by opening a reference hole (not shown) on each substrate and laminating the pin on the pressure heating jig.

In the step of laminating the steps of Fig. 1 (3) and (k), since the pressure of the prepreg materials 102 and 112 is not applied, the resin does not flow and is not heated to the temperature at which the resin is hardened, so the prepreg materials 102 and 112 are not Hardened state.

Then, as shown in Fig. 1 (3) and (m), the laminated body of the insulating substrate A121, the insulating substrate B122, and the wiring member 131 is heated and integrated to form the circuit component-embedded substrate 141.

In addition, by using the multilayer printed substrate by the wiring member 131, only In the steps shown in Fig. 1 (3) ((k) and (m)), a multilayer circuit element-embedded substrate having a high wiring density can be manufactured.

Further, the steps shown in Fig. 1 (3) (k) and Fig. 1 (3) (m) are examples of the laminating pressurization heating step of the present invention.

Further, the heating in the pressure heating treatment step of Fig. 1 (3) (m) is performed at a temperature higher than the temperature at which the thermosetting resin in the prepreg materials 102 and 112 and the inner through holes 105b and 115b is cured (for example, 150 ° C to 260 ° C). )get on. By this heating, the prepreg 102 of the insulating substrate A121, the prepreg 112 of the insulating substrate B122, the circuit component 106, and the wiring member 131 can be mechanically strengthened. Further, the electrode terminal of the circuit component 106 and the electrode terminal 132 formed on the wiring component 131 can be electrically connected via the inner via hole 115b.

Further, in the step of the heat treatment of Fig. 1 (3) (m), when the thermosetting resin in the prepreg materials 102 and 112 and the inner through holes 105b and 115b is heated by heating, the pressure is applied by one side while being heated. Pressurization from 1 MPa to 20 MPa can improve the mechanical strength of the built-in substrate 141 of the circuit component. Further, by filling the gap between the through hole 103 and the circuit element 106 with the molten resin or sufficiently compressing the inner through holes 105b and 115b, electrical connection in a good state can be obtained. The same applies to the following embodiments.

Further, in the pressure heating step of Fig. 1 (3) (m), the viscosity of the resin in the semi-hardened prepreg 102 is temporarily lowered by applying a high pressure in a high-temperature vacuum state of 150 ° C to 260 ° C. Flow occurs due to the application of pressure. Therefore, the gap between the inner through hole 105b and the wall surface of the through hole 104 is filled by the prepreg 102, and then the resin of the prepreg 102 is completely hardened. Therefore, after the pressure heating step of Fig. 1 (3) (m), the inner through hole 105b and the pre The immersion material 102 will be in a closed state without gaps.

In the method of manufacturing the circuit element-embedded substrate 141 of the first embodiment, since the step of directly filling the electrode assembly 105a with the electrode terminal of the circuit element 106 is performed, even a gap is formed in the prepreg 102 and the circuit element 106. There is still no short circuit between the electrode terminals of the circuit component 106. Further, as shown in Fig. 1 (1) and (e), since the conductive composition 105a is printed and printed on the insulating substrate A121, it is easy to handle in the step.

In the structure of the first embodiment, the thickness of the prepreg 102 is set to 0.54 mm with respect to the length of the circuit component 106 of 0.6 mm, so that the circuit component 106 is 0.03 mm from the one side of the prepreg 102. Moreover, by setting the film thickness to 0.02 mm, as shown in Fig. 1 (1) and (f), when the circuit component 106 is inserted, it can be arranged substantially in the vicinity of the center of the thickness direction of the prepreg 102.

Further, the diameter of the inner through hole 115b (diameter 0.15 mm) is set to be smaller than the inner through hole 105b (diameter: 0.2 mm), or the electrode terminal size of the circuit element 106 (diagonal angle: 0.37 mm), and the electrode terminal 132 of the wiring member 131. Since the size (diameter: 0.3 mm) is small and the difference in buildup can be absorbed, the high-density built-in element can still be a circuit element built-in substrate 141 having no problem of insulation between adjacent elements.

Further, after the pressure heating step, the inner through hole 105b in the circuit board built-in substrate 141 is a columnar shape as shown in Fig. 1 (3) and (m), and the cylindrical side surface is straight in the height direction. On the other hand, as shown in FIG. 8(i), in the conventional circuit element-embedded substrate 241, the inner through hole 205b after the pressure heating step has a curved shape in the height direction, and the first embodiment is curved. Manufacturing The inner through holes 105b produced by the method are in a different shape.

2(a) and 2(b) are partial cross-sectional views showing a combination of material structures in the laminating step shown in Fig. 1 (3) and (k) of the method for manufacturing the circuit element-embedded substrate 141 of the first embodiment. structure map.

The appropriate range of the thickness of the prepreg material 102 is preferably -0.2 to +0.08 mm (one side: -0.1 to +0.04 mm) with respect to the length of the built-in circuit component 106. In other words, when the thickness of the prepreg material 102 is used as a reference, it is preferable to set the amount of protrusion of the circuit element 106 on one side to a range of -0.04 to +0.1 mm.

The reason will be explained below.

The amount of protrusion of the through hole 115b in the insulating substrate B122 is related to the thickness of the film 111. The film 111 is used in a thickness of 0.005 to 0.05 mm in view of the relationship between the handleability and the peelability and the thickness of the insulating substrate B122.

Figure 2 (a) is a circuit component 106 protruding from the prepreg material 102 An example of the state is, for example, a partial cross-sectional structural view of a structure in which the size A1 of the circuit element 106 is +0.1 mm (the upper limit of the appropriate range) and the amount of protrusion B1 of the inner through hole 115b is 0.005 mm.

In the laminated state shown in Fig. 2(a), the inner through hole 115b has a compression amount (A1 + B1) in a state of abutting against the electrode terminal of the circuit component 106, so that Fig. 1 (3) (m) of the subsequent step In the pressurized heating step shown, the pressure will be transmitted to the inner through hole 115b, and a good connection can be obtained. When the amount of protrusion A1 of the circuit component 106 is increased to more than necessary, the thickness of the insulating substrate B122 for absorbing the protruding of the circuit component 106 is increased, so that the circuit component is pressurized. It is difficult for the 106 to stay in the center of the inner layer, and the amount of compression of the through hole 115b in the upper and lower sides is likely to be different, and the connection reliability is deteriorated. Moreover, it is difficult to arrange the circuit component 106 inserted into the through hole 103 in the center of the thickness direction of the prepreg 102.

2(b) shows an example in which the circuit component 106 is recessed from the prepreg material 102, for example, the projection amount A2 of the circuit component 106 is -0.04 mm (the lower limit of the appropriate range) and the inner through hole 115b is convex. A partial cross-sectional structural view of a structure in which B2 is 0.05 mm.

When the laminated state is as shown in Fig. 2(b), the size of the compression amount (B2 + A2) will be +0.01 mm, so that it can be in the pressure heating step shown in Fig. 1 (3) (m) of the subsequent step. Pressure is applied to the inner through hole 115b. When the amount of recess of the circuit component 106 of the prepreg 102 is 0.04 mm or more (that is, when A2 < -0.04 mm), the amount of protrusion of the inner via 115b cannot be increased from the thickness setting limit of the film 111. B2, in the pressurization heating step shown in Fig. 1 (3) (m) of the subsequent step, it is impossible to apply pressure to the inner through hole 115b.

It is preferable to set the thickness of the prepreg material 102 so that the protruding amount of the circuit component 106 is one side +0.03 to +0.08 mm, but when the thickness of the insulating substrate A121 exceeds an ideal value when the thickness of the insulating material is limited. As described above, by adjusting the amount of protrusion of the inner through hole 115b, even if the circuit component 106 is recessed from the surface of the prepreg material 102, it can be connected without problems.

3(a) and 3(b) are diagrams showing a combination of material structures after the pressure heating step shown in Fig. 1 (3) and (m) of the method for manufacturing the circuit element-embedded substrate 141 of the first embodiment. Partial section construction diagram.

Figure 3 (a) shows the pressurized heat treatment in the configuration shown in Figure 2 (a) The partial cross-sectional structural view after FIG. 3(b) shows a partial cross-sectional structural view of the structure shown in FIG. 2(b) after the pressure heat treatment.

A suitable range of the thickness of the prepreg 112 is preferably 0.03 mm or more and 0.2 mm or less. The reason will be explained below.

Wiring element 131 The thickness of the electrode terminal 132 is generally about 0.005 to 0.05 mm.

As shown in FIG. 3(a), the circuit component 106 protrudes from the prepreg material 102. At this time, the prepreg 112 is required to have a thickness of the absorption circuit element 106 (maximum 0.1 mm) and the thickness of the electrode terminal 132 of the wiring member 131 (maximum 0.05 mm). When the thickness of the inner through hole 115b after compression is at least 0.05 mm, the thickness (C1) of the prepreg 112 is required to be about 0.2 mm. However, when the thickness C1 is 0.2 mm or more, the prepreg 112 has a two-piece structure, which causes a cost increase, and the thickness of the circuit board built-in substrate 141 becomes thick.

As shown in FIG. 3(b), the thickness (C2) of the prepreg 112 is such that the thickness (minimum 0.005 mm) of the electrode terminal 132 can be absorbed without causing the circuit component 106 to protrude from the prepreg material 102. However, the thickness of the prepreg 112 itself and the viewpoint of ensuring the peeling property of the film 111 and the amount of protrusion of the through hole 115b in the stable state or the thickness of the material to be obtained may be 0.03 mm or more.

2(a) and 2(b), there is a gap between the upper and lower surfaces of the electrode terminals of the circuit element 106 that are not in contact with the inner via 115b and the insulating substrate B122, but in FIG. 1 (3) In the pressure heating step of (m), the resin in the prepregs 102 and 112 softens and flows, and fills the gap. because As shown in Fig. 3 (a) and Fig. 3 (b), after the pressure heating step of Fig. 1 (3) (m), the electrode terminal of the circuit element 106 and the insulating substrate B 122 are in a state of no gap.

On the other hand, the inner through hole 115b is columnized by the heat treatment of Fig. 1 (2) (i), and it is difficult to flow even under pressure heating in the pressure heating step of Fig. 1 (3) (m). Therefore, in the pressure heating step of Fig. 1 (3) (m), the portion of the inner through hole 115b will not flow into the gap between the circuit component 106 and the prepreg 102, or the gap between the circuit component 106 and the insulating substrate B122. The resin of the prepreg material 102 or 112 will soften and flow into and fill the gaps.

The diameter L of the through hole 115b formed in the insulating substrate B122 is 0.03 mm or more and 0.3 mm or less, and the diagonal dimension of the electrode terminal of the built-in circuit component 106 is preferably equal to or less. The reason will be explained below.

4(a) to 4(c), a cross-sectional structural view before and after peeling off the peeling film 111 in the manufacturing process of the insulating substrate B122 is shown. 4(a) to 4(c) are cross-sectional structural views showing an insulating substrate B122 having a structure in which the diameters of the through holes 113 are different.

In the step of filling the conductive composition in FIG. 1 (2) (i), when the conductive composition 115a is filled and filled in the through hole 113 formed in the insulating substrate B122, the squeegee is passed through the squeegee of the conductive composition 115a. Take a little bit and become a recessed state. Therefore, the larger the through hole diameter, the greater the influence and the deeper the concave amount.

For example, when the thickness of the coating film 111 is 0.02 mm, as shown in FIG. 4(a), if the diameter L1 of the through hole 113 is 0.15 mm, the concave amount after filling the conductive composition 115a is about 0.01 mm, as shown in FIG. As shown in the right figure of (a), after the film 111 is peeled off, the inner through hole 115b is in a state of being protruded from the surface of the prepreg 112. In the pressure heating step shown in Fig. 1 (3) and (m) of the subsequent steps, since the inner through hole 115b is sufficiently compressed, a good connection reliability state can be obtained.

When the diameter L of the inner through hole 115b is less than 0.03 mm, the connection area between the electrode terminal of the circuit element 106 and the electrode terminal 132 of the wiring element 131 is small, and the connection reliability is deteriorated.

As shown in Fig. 4(b), if the diameter L2 of the through hole 113 is 0.25 mm, the concave amount after the filling of the conductive composition 115a is about 0.02 mm, as shown in the right figure of Fig. 4(b), the film is peeled off. After 111, the inner through hole 115b has the same height as the surface of the prepreg 112.

As shown in Fig. 4(c), if the diameter L3 of the through hole 113 is 0.3 mm, the concave amount after filling the conductive composition 115a is about 0.03 mm, as shown in the right figure of Fig. 4(c), the film is peeled off. After the 111, the inner through hole 115b is recessed toward the surface of the prepreg 112, and the pressure heating step shown in Fig. 1 (3) (m) of the subsequent step will not easily apply pressure to the inner through hole 115b, and the wiring member 131 A gap is formed between the electrode terminals 132 to deteriorate the electrical connection reliability. However, even if the diameter L3 of the through hole 113 is 0.3 mm and the thickness of the thick film 111 is 0.05 mm, the inner through hole 115b can be made to protrude from the surface of the prepreg 112 after the film 111 is peeled off.

(a) and (b) of FIG. 5 are cross-sectional structural views showing the circuit element-containing substrate 141 after the pressure heating step shown in Fig. 1 (3) and (m) of the first embodiment.

5(a) is a cross-sectional structural view showing a circuit element-embedded substrate 141 having a structure in which the diameter of the through hole 115b formed in the insulating substrate B122 is smaller than the diameter of the electrode terminal 132 of the wiring member 131, and FIG. 5(b) ) display A cross-sectional structural view of the circuit element-accommodating substrate 141 having a structure in which the diameter of the inner through hole 115b is larger than the diameter of the electrode terminal 132.

Since the purpose of the built-in circuit element 106 in the longitudinal direction of the thickness direction of the substrate is high-density mounting, as shown in FIGS. 5(a) and 5(b), the built-in circuit element 106 is densely arranged. Therefore, as shown in FIG. 5(b), when the diameter of the inner through hole 115b is set larger than the diameter of the electrode terminal 132 of the wiring member 131 by 0.3 mm, there is a problem that insulation properties of adjacent elements are deteriorated. The displacement due to the processing accuracy or the lamination accuracy of the various structural elements, and the internal through-hole 115b being compressed during the pressurization heating step in the subsequent step are caused to cause the inner through-hole 115b to become large.

Further, the built-in circuit component 106 is small, and the purpose of incorporating the circuit component 106 at a high density is to reduce the diameter of the electrode terminal 132 of the wiring component 131 by matching the diagonal dimension of the electrode terminal of the circuit component 106. At this time, the maximum size of the diameter of the inner through hole 115b is set to be equal to or less than the diagonal dimension of the electrode terminal of the circuit component 106.

In the first embodiment, for the purpose of electrically connecting the upper and lower wiring elements 131, the structure in which the prepreg 102 is provided with the inner via hole 105b is described. However, the upper and lower wiring elements can be connected only by the built-in circuit element 106. There are 131 electrical connections, and when the circuit is designed, the inner through hole 105b is not required. At this point, the steps of Figure 1 (1) (c) ~ Figure 1 (1) (e) can be omitted Omitted, as long as the step does not contaminate the surface of the prepreg 102, the film 101a may not be attached.

(Embodiment 2)

6(1)((a)~(c)), Fig. 6(2)((d)~(g)), Fig. 6(3)((h) and (i)) are used to illustrate the present invention Method for manufacturing circuit element built-in substrate according to second embodiment A cross-sectional structural diagram of each step. The same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted.

Fig. 6 (1) ((a) to (c)) show the manufacturing steps of the insulating substrate A in which the circuit element and the conductive element are built, and Fig. 6 (2) ((d) to (g)) are used for display formation. A manufacturing step of connecting the electrode terminal of the circuit element to the insulating substrate B of the conductive element and the inner via hole of the electrode terminal of the wiring element, and FIG. 6 (3) ((h) and (i)) showing the laminated integrated insulating substrate A. Manufacturing steps of the insulating substrate B and the wiring member.

First, the manufacturing steps of the insulating substrate A shown in Fig. 6 (1) ((a) to (c)) will be described.

In the manufacturing step of the insulating substrate A123, that is, in FIG. 6(1)(a), the electrically insulating substrate material is integrated, for example, by laminating a plurality of sheets of a common printed circuit board material, which is a prepreg material. The prepreg 102 having a thickness of 0.54 mm is formed into a through hole 103 having a diameter of 0.37 mm by drilling, laser processing or the like.

Thereafter, as shown in FIGS. 6(1) and (b), the circuit component 106 is inserted at a desired position of the through hole 103. Thereafter, as shown in FIGS. 6(1) and (c), the conductive element 107 is inserted at a desired position of the through hole 103. As the conductive member 107, a metal bar can be used. When the copper bar is subjected to oxidation resistance such as gold plating or tin plating, the conductivity is low and the conductive composition is in a good connection state.

Further, the conductive element 107 is an example of a conductive element having a shape of the present invention.

In the second embodiment, the through hole with respect to the prepreg 102 103, the conductive element 107 is inserted after the circuit element 106 is inserted, but even if the order of insertion is changed, there is no problem even if it is randomly inserted. Further, any of the through holes 103 is formed to have the same size. However, the size of the through hole 103 may be individually set in accordance with the size of the conductive element 107.

In the insulating substrate A123 of the second embodiment, since the inner through hole is not formed by the conductive composition, the film is not attached to the surface of the prepreg 102, but the film may be attached to protect the prepreg 102. surface.

Next, a manufacturing procedure of the insulating substrate B shown in Fig. 6 (2) ((d) to (g)) will be described. The insulating substrate B is the same as the manufacturing steps described in the first embodiment using FIG. 1 (2) ((g) to (j)).

6(2) and (d) show a film 111 having a thickness of 0.02 mm laminated on both main surfaces of a prepreg 112 having a thickness of 0.14 mm in the step of attaching a film.

Fig. 6(e) is a through hole 113 having a diameter of 0.15 mm which is processed by drilling at a position where the inner through hole 115b is desired to be formed in the through hole forming step.

In FIG. 6(f), in the step of filling the conductive composition and the heat treatment step, the conductive composition 115a is filled by printing on the through hole 113. Thereafter, the conductive composition 115a is pillared by heat treatment to form an inner via hole 115b.

In Fig. 6(g), in the film peeling step, the film 111 is removed by peeling, whereby the insulating substrate B122 having the inner through holes 115b formed therein can be manufactured.

Next, the step of integrating the layers shown in Fig. 6 (3) ((h) and (i)) will be described.

As shown in Figure 6 (3) (h), on the two main faces of the insulating substrate A123 The insulating substrate B122 is laminated and placed on the outer surface of the insulating substrate B122 to laminate the wiring elements 131. At this time, the electrode terminal of the circuit element 106 formed on the insulating substrate A123 and the conductive element 107, the through hole 115b formed in the insulating substrate B, and the electrode terminal 132 of the wiring member 131 (for example, a through hole region having a diameter of 0.3 mm) ), aligning at the time of lamination, and arranging on the same coordinate.

Then, as shown in Fig. 6 (3) and (i), the laminated body of the insulating substrate A123, the insulating substrate B122, and the wiring member 131 is heated and integrated to form the circuit element-embedded substrate 142.

As described above, in the second embodiment, the conductive element 107 as the metal bar is used instead of the inner through hole 105b using the conductive composition 105a used in the first embodiment, and the structure is electrically connected. Thereby, the step of filling the conductive composition without printing the insulating substrate A123 can be greatly reduced. Further, the same effect can be obtained by using the 0 Ω chip resistor (jumper resistance) as the conductive element 107.

Further, the prepreg materials 102 and 112 used in the respective embodiments do not have a thickness change after the pressure heating. However, when the insulating substrate material which is shrunk in the thickness direction after pressurization heating is used, it is possible to preliminarily assume the shrinkage amount and set the insulation. The material thickness of the substrate.

Fig. 7 is a partial cross-sectional photograph of a circuit element-embedded substrate produced by the manufacturing method of the first or second embodiment, and is a portion in which a circuit element-embedded substrate having a chip resistance of 0.6 × 0.3 mm as a circuit element 106 is housed. Zoom in on the photo.

As explained above, in accordance with the present invention, for performing relative to the base The formation of the through-holes in the electrical connection between the electrode terminals of the circuit elements and the electrode terminals of the wiring elements in the thickness direction of the board is not formed directly on the electrode terminal portions of the circuit elements, and is additionally prepared for thin Since the insulating material forms the inner through hole and is pillared and then laminated and integrated, it is not necessary to define an insulating material, and any short circuit between the electrode terminals of the circuit element can be prevented regardless of the use of any material.

Therefore, according to the present invention, it is possible to provide a high-density built-in circuit component even if a general-purpose material, that is, a low-cost prepreg or the like is used as an insulating material for a built-in circuit component, and a short circuit between terminals of the circuit component is not generated. Further, a method of manufacturing a built-in substrate of a circuit component having electrical connection reliability is further improved.

Industrial availability

In the method for producing a circuit element-embedded substrate of the present invention, a prepreg containing a thermosetting epoxy resin as a main component is used, and the effect of improving the reliability of electrical connection is obtained, and the substrate can be built in a circuit element and the circuit element is built in. Modules, etc. are used.

101a, 101b, 111‧‧ ‧ film

102,112‧‧‧Prepreg

103‧‧‧through holes

104,113‧‧‧through hole

105a, 115a‧‧‧ Conductive composition

105b, 115b‧‧‧through hole

106‧‧‧ Circuit components

131‧‧‧Wiring components

132‧‧‧electrode terminal

121,122‧‧‧Insert substrate

141‧‧‧ Built-in substrate for circuit components

Claims (8)

A method of manufacturing a circuit board built-in substrate, comprising: a circuit element mounting step of forming one or a plurality of through holes in a thickness direction of a material of the first insulating substrate, and inserting the circuit elements into all or a part of the through holes; The upper and lower electrode terminals face the thickness direction; the inner via hole forming step forms one or a plurality of first via holes in the thickness direction of the material of the second insulating substrate, and fills the first conductive layer with the first conductive layer And forming a first inner through hole for electrical connection; and a laminated pressure heating step of arranging the first inner through hole on each of the surfaces of the first insulating substrate on which the circuit element is inserted The material of the second insulating substrate is disposed on the outer surface of the material of the second insulating substrate, and the wiring member is laminated and pressurized, and the electrode terminal of the circuit element and the first electrode are laminated and heated. The inner through holes are disposed at respective positions, and the first inner through holes and the electrode terminals formed on the wiring elements are disposed at respective positions. The method of manufacturing a circuit board built-in substrate according to the first aspect of the invention, wherein the step of mounting the circuit element forms one or a plurality of the through holes, and before inserting the circuit elements into all or a part of the through holes, a film for blocking an opening of the through hole is attached to the first insulating substrate, and is coupled to the first insulating base together with the coating film One or a plurality of second through holes are formed in the thickness direction of the material of the plate, and the second conductive holes are filled in the second through holes to form a second inner through hole for electrical connection. A method of producing a circuit element-embedded substrate according to the second aspect of the invention, wherein the first insulating substrate is a prepreg containing epoxy resin as a main component. The method of manufacturing a circuit board built-in substrate according to the first aspect of the invention, wherein, in the step of mounting the circuit element, one or a plurality of the through holes are formed, and the circuit element is inserted into the through hole and the through hole A part of the conductive element is inserted into the shape. The method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, wherein the thickness of the material of the first insulating substrate is -0.2 mm or more and +0.08 mm or less in length of the circuit element incorporated in the first insulating substrate. The method of manufacturing a circuit element-embedded substrate according to the first aspect of the invention, wherein the material of the second insulating substrate has a thickness of 0.03 mm or more and 0.2 mm or less. The method of manufacturing a circuit board built-in substrate according to the first aspect of the invention, wherein the electrode terminal of the circuit element is rectangular, and a diameter of the first through hole formed in the material of the second insulating substrate is 0.03 mm or more and 0.3. It is less than mm and is equal to or less than the diagonal dimension of the electrode terminal of the above-mentioned circuit component. The method of manufacturing a circuit board built-in substrate according to the first aspect of the invention, wherein the wiring element is a multilayer printed board.