JP2007258635A - Method for manufacturing built-in component substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a built-in compact substrate which is satisfactory in productivity. <P>SOLUTION: This method for manufacturing a built-in component substrate 100 includes a process (a) for laminating a first substrate 10 and a second substrate 20 on which an electronic component 12 is mounted through a resin interposition layer 30 in which an inter-layer connection member 32 is formed and a process (b) for holding and pressing the first substrate 10 and the second substrate 20 with the resin interposition layer 30 interposed by an upper mold 50 and a lower mold 40. In the process (b), an elastic member 60 is interposed between the upper mold 50 and the lower mold 40, and press is executed in such a status that at least a side face 34 of the resin interposition layer 30 is covered by the elastic member 60. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a component-embedded substrate in which electronic components are embedded.

  With recent downsizing, thinning and higher functionality of electronic equipment, there is a demand for higher density mounting of electronic components mounted on printed circuit boards and higher functionality of circuit boards mounted with electronic components. It is getting stronger and stronger. Under such circumstances, a component-embedded substrate in which an electronic component is embedded in the substrate has been developed (for example, Patent Document 1 and Patent Document 2).

  In a component-embedded board, active parts (for example, semiconductor elements) and passive parts (for example, capacitors) mounted on the surface of a printed circuit board are usually embedded in the board, so that the area of the board can be reduced. it can. In addition, since the degree of freedom for arranging electronic components is higher than in the case of surface mounting, improvement of high frequency characteristics can be expected by optimizing the wiring between the electronic components.

  Today, in the field of ceramic substrates, LTCC (low temperature coherent ceramics) substrates with built-in electronic components have been put into practical use, but this is difficult to apply to large substrates because it is heavy and fragile, and high temperature processing Therefore, there are significant restrictions such as the inability to incorporate semiconductor elements such as LSI. Recently, a component-embedded substrate in which components are embedded in a printed circuit board using resin, unlike an LTCC substrate, there are few restrictions on the size of the substrate, and an LSI can be incorporated. It also has the advantage.

  Next, a component built-in substrate (circuit component built-in module) disclosed in Patent Document 1 will be described with reference to FIG. A circuit component built-in module 400 shown in FIG. 1 includes a substrate 401 in which insulating substrates 401a, 401b, and 401c are stacked, wiring patterns 402a, 402b, 402c, and 402d formed on the main surface and inside of the substrate 401, The circuit component 403 is arranged inside the 401 and connected to the wiring pattern. The wiring patterns 402a, 402b, 402c and 402d are electrically connected by an inner via 404, and the insulating substrates 401a, 401b and 401c are made of a mixture containing an inorganic filler and a thermosetting resin. Yes.

The component-embedded substrate 400 shown in FIG. 1 is also called SIMPACT ^™ . When this technology is applied to, for example, a high-frequency circuit, as shown in FIG. 2, the substrate area of a circuit board 500 (500a, 500b, 500c, 500d) employing a general technology is reduced to, for example, about 1/4. can do.

  The manufacturing method of the component-embedded substrate 400 will be briefly described as shown in FIGS.

  First, as shown in FIG. 3A, via holes are formed in a sheet 410 made of a composite material containing an inorganic filler and a thermosetting resin, and then the via holes are filled with a conductive via paste 414, and then copper An LSI chip 403 a and a passive component 403 b previously placed on the foil 420 are arranged around the sheet 410.

Next, as illustrated in FIG. 3B, the LSI chip 403 a and the passive component 403 b are embedded in the sheet 410. Then, as shown in FIG. 3C, when the sheet 410 is heated and cured to form the wiring pattern 412 from the copper foil 420, a component built-in substrate is obtained. When this component-embedded substrate is laminated, a multilayered component-embedded substrate 400 as shown in FIG. 3D can be produced.
Japanese Patent Laid-Open No. 11-220262 JP 2003-179356 A

  When the component-embedded substrate is manufactured, when embedding the LSI chip 403a and the passive component 403b in the sheet 410, as shown in FIGS. 4 (a) and 4 (b), the conductive material that connects the layers by the flow 411 of the composite material The shape of the via paste (inner via 414) may change. If the shape of the conductive via paste is deformed, the connection cannot be obtained due to the positional deviation of the inner via 414, or the connection resistance increases.

  In particular, as shown in FIGS. 5A and 5B, the composite material flows and protrudes from the substrate 420 at the end of the substrate 420 (see the arrow 415), so that the positional deviation of the inner via 414 is maximized. . Therefore, normally, the end portion of the substrate 420 becomes an area where the inner via 414 cannot be formed (via prohibited area), and is cut after being crimped by a hot press.

  FIGS. 6A and 6B show the ratio of the via prohibition area 210 in the entire substrate. FIGS. 6A and 6B show the case of a multi-piece substrate and a single-piece substrate. In any of the substrates, an area included in a certain distance (L250) from the edge of the substrate is the above-described via prohibited area 210. In addition, the ratio of the via-forbidden area 210 occupying the entire board area is higher in the single-piece cutting than in the multi-piece cutting, and the ratio corresponds to about 2/3 of the total area.

  If the ratio of via-prohibited areas is large, board resources are wasted, material costs per product increase, and good productivity is impaired.

  The present invention has been made in view of such circumstances, and a main object thereof is to provide a method for manufacturing a component-embedded substrate with good productivity.

  According to another aspect of the present invention, there is provided a method of manufacturing a component-embedded substrate comprising: a first substrate on which an electronic component is mounted; and a second substrate provided to face the first substrate. The step (a) of laminating through the resin intervening layer in which the interlayer connection member for ensuring electrical connection is formed, and the first substrate and the second substrate interposing the resin intervening layer are divided into an upper die and a lower die. A step (b) of sandwiching and pressing between molds, wherein an elastic member is interposed between the upper mold and the lower mold in the step (b), and the elastic member is at least a side surface of the resin intervening layer during pressing. It is characterized by executing the press in a state of covering.

  In a preferred embodiment, in the step (b), the elastic member is interposed between the upper mold and the second substrate and between the lower mold and the first substrate, and the elastic member is pressed during the pressing. The member wraps around the side surface of the resin intervening layer.

  In a preferred embodiment, in the step (b), the side surface of the resin intervening layer is pushed back by the elastic force of the elastic member.

  The elastic member is a rubber sheet made of silicone rubber, and the rubber sheet is interposed between the lower mold and the first substrate, and between the upper mold and the second substrate. It is preferable that the second sheet is formed.

  The sum of the thickness of the first sheet and the thickness of the second sheet is preferably equal to or greater than the sum of the thickness of the first substrate, the thickness of the second substrate, and the thickness of the resin intervening layer.

  It is preferable that the thickness of the first sheet is the same as the thickness of the second sheet.

  In a preferred embodiment, the first sheet has a recess for receiving the first substrate, while the second sheet has a recess for receiving the second substrate. .

  The resin intervening layer is preferably composed of a composite sheet containing at least a thermosetting resin and an inorganic filler, and in the step (b), the electronic component is preferably embedded in the composite sheet.

  In a preferred embodiment, the first substrate on which the electronic component is mounted includes a plurality of substrate blocks serving as a unit of individual component-embedded substrates. After the step (b), each of the substrates The step of cutting into blocks is further performed.

  In a preferred embodiment, a plurality of substrate combinations in which the first substrate, the second substrate, and the resin intervening layer are combined in the step (a) are prepared, and a plurality of substrate combinations are prepared in the step (b). These substrate combinations are pressed together in the same process.

  In a preferred embodiment, in the step (a), a third substrate is further laminated on the second substrate via a resin intervening layer, and in the step (b), the resin intervening layer is interposed. The first substrate, the second substrate, and the third substrate are pressed by being sandwiched between an upper die and a lower die.

  According to the method for manufacturing a component-embedded substrate of the present invention, an elastic member is interposed between the upper die and the lower die, and the pressing is performed in a state where the elastic member covers at least the side surface of the resin intervening layer at the time of pressing. The flow of the resin intervening layer, particularly the flow of the substrate end region can be suppressed. As a result, it is possible to prevent the displacement of the interlayer connection member formed in the resin intervening layer, particularly the interlayer connection member located at the edge of the substrate, and to provide a method for manufacturing a component-embedded substrate with good productivity. Can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity. In addition, this invention is not limited to the following embodiment.

  A method for manufacturing the component-embedded substrate 100 according to the embodiment of the present invention will be described with reference to FIGS. 7A to 7B are process cross-sectional views schematically showing the manufacturing process in the present embodiment.

  In the manufacturing method of the present embodiment, as shown in FIG. 7A, first, the first substrate 10 on which the electronic component 12 (12a, 12b) is mounted and the second substrate provided opposite to the first substrate. The substrate 20 is prepared and laminated with the resin intervening layer 30 interposed between the first substrate 10 and the second substrate 20. The electronic component 12a of the present embodiment is a semiconductor element such as a bare chip IC, for example, and the electronic component 12b is a passive component such as a chip component such as a chip inductor, a chip resistor, and a chip capacitor.

  In addition, an interlayer connection member 32 that electrically connects the first substrate 10 and the second substrate 20 is formed in the resin intervening layer 30 interposed between the first substrate 10 and the second substrate 20. The interlayer connection member 32 of the present embodiment is an inner via, and is formed by performing hole processing (for example, punching) on the resin intervening layer 30 and filling the conductive paste therewith. In particular, the inner via formed at the end of the substrate is referred to as an inner via 33.

  Also, the lower mold 40 is prepared below the first substrate 10, while the upper mold 50 is prepared above the second substrate 20, and the elastic member 60 is disposed between the lower mold 40 and the upper mold 50. To do. The lower mold 40 and the upper mold 50 of the present embodiment are both made of a metal material such as stainless steel (SUS304).

  Subsequently, as shown in FIG. 7B, the first substrate 10 and the second substrate 20 with the resin intervening layer 30 interposed therebetween are sandwiched between the upper mold 50 and the lower mold 40 and pressed in the direction of the arrow 150. In this pressing step, pressing is performed in a state where the elastic member 60 interposed between the upper mold 50 and the lower mold 40 covers at least the side surface 34 of the resin intervening layer 30 during pressing.

  In the present embodiment, the first substrate 10 and the second substrate 20 are sandwiched between the upper die 50 and the lower die 40 and pressed from above and below (in the direction of the arrow 150). Is a term for convenience and is not limited to pressing from above and below. For example, the first substrate 10, the resin intervening layer 30, and the second substrate 20 may be stacked vertically, and the upper die 50 and the lower die 40 may be used to perform pressing from the lateral direction.

  According to the manufacturing method of this embodiment, the elastic member 60 is interposed between the upper die 50 and the lower die 40, and the pressing is performed in a state where the elastic member 60 covers at least the side surface 34 of the resin intervening layer 30 during pressing. Therefore, the resin intervening layer 30 does not protrude to the outside of the substrate during pressing, and the flow of the resin intervening layer 30, particularly the flow of the substrate end region can be suppressed.

  Therefore, it is possible to prevent displacement of the inner vias 32 formed in the resin intervening layer 30, particularly the inner vias 33 located at the end of the substrate. As a result, the inner via 33 can be formed at the end of the substrate, so that the ratio of the via-prohibited area in the substrate can be reduced, and the substrate resources are not wasted, and each product is not used. Therefore, productivity can be improved.

  Below, the manufacturing method of this embodiment is explained in full detail.

  First, as shown in FIG. 7A, the first substrate 10 on which the electronic component 12 is mounted is prepared, and the resin intervening layer 30 in which the inner vias 32 and 33 are formed above the first substrate 10. Are aligned and stacked. Next, the second substrate 20 is aligned and laminated above the resin intervening layer 30.

  The resin intervening layer 30 of the present embodiment may be mixed with a material other than resin. For example, the resin intervening layer 30 of the present embodiment is made of a resin material in which at least a thermosetting resin and an inorganic filler are mixed. It is a composite sheet.

  This is because the characteristics of the composite sheet 30 can be adjusted by the inorganic filler. For example, the coefficient of thermal expansion between the composite sheet 30 and the built-in semiconductor element 12a can be adjusted, or the semiconductor element 12a can be adjusted. It becomes easy to improve heat dissipation.

  Moreover, in this lamination | stacking stage, it is preferable that the thermosetting resin contained in the composite sheet 30 is a semi-hardened state so that it may be easy to handle. Here, the semi-cured resin is a resin in which the curing reaction is stopped at an intermediate stage, and this semi-cured state is referred to as a B-stage. The B-stage resin is softened (melted) once by being heated, and is further cured by continuing to be heated. This fully cured state is referred to as the C-stage.

  Next, the lower mold 40 is prepared below the first substrate 10, while the upper mold 50 is prepared above the second substrate 20, and between the upper mold 50 and the second substrate 20 and the lower mold 40. Two elastic members 60 are disposed between the first substrate 10 and the first substrate 10.

  The elastic member 60 used in this embodiment is two rubber sheets 60 (60a, 60b) made of silicone rubber. The rubber sheet 60a is disposed between the lower mold 40 and the first substrate 10, while the upper A rubber sheet 60 b is disposed between the mold 50 and the second substrate 20.

  In the present embodiment, the method of arranging the lower mold 40, the upper mold 50, and the elastic body 60 after aligning and laminating the first substrate 10, the second substrate 20, and the resin intervening layer 30 has been described. However, a method in which the arrangement of the lower mold 40, the upper mold 50, and the elastic body 60 and the lamination of the first substrate 10, the second substrate 20, and the resin intervening layer 30 are performed in parallel may be used. For example, the elastic body 60 is disposed above the lower mold 40, the first substrate 10 is disposed above the elastic body 60, the resin intervening layer 30 is aligned and laminated thereon, and the second substrate is disposed thereon. There is a method in which 20 is aligned and laminated, an elastic body 60 is further disposed thereon, and an upper mold 50 is further disposed thereon.

  Finally, as shown in FIG. 7B, the first substrate 10 and the second substrate 20 with the resin intervening layer 30 interposed therebetween are sandwiched between the upper die 50 and the lower die 40 and pressed in the direction of the arrow 150. . In this pressing step, the rubber sheet 60a disposed between the lower mold 40 and the first substrate 10 and the rubber sheet 60b disposed between the upper mold 50 and the second substrate 20 are compressed during pressing, By deforming, it wraps around the side surface 34 of the composite sheet 30. Therefore, the above-described pressing is performed in a state where the side surface 34 of the composite sheet 30 is covered with the rubber sheet 60 (60a, 60b).

  In addition, the press process of this embodiment includes the process of heating further, and the thermosetting resin mixed in the composite sheet 30 is hardened by heating. Thereby, each component is thermocompression bonded, and the component built-in substrate 100 is obtained.

  In addition, the composite sheet 30 that has been in the B-stage in the lamination stage is softened (melted) once by being heated in this hot pressing step, and is further completely cured by continuing to be heated to reach the C-stage. . Once softened, it becomes easy to embed the electronic component 12. Moreover, the composite sheet 30 is in a state of good wettability with respect to the substrate by being softened, and then the adhesive force between the composite sheet 30 and the substrate becomes strong by being completely cured.

  According to the manufacturing method of this embodiment, the rubber sheet 60 (60a, 60b) wraps around the side surface 34 of the composite sheet 30 and covers the side surface 34 at the time of hot pressing. It is possible to suppress a flow that tends to protrude to the outside of the substrate, and to prevent the positional deviation of the inner via 33 formed at the end of the substrate. As a result, since the inner via 33 can be formed at the end portion of the substrate, the substrate can be used effectively and the productivity can be improved.

  In addition, in the hot pressing process, it is only necessary to execute the press with the stretchable rubber sheet 60 interposed therebetween, and the side surface 34 of the composite sheet 30 can be covered without preparing a special concave mold. Since it is possible, it is very simple. Furthermore, since the rubber sheet 60 can be expanded and contracted, it is not necessary to align with high accuracy, and it is possible to cope with the size of an arbitrary substrate.

  Next, a mechanism that suppresses the flow of the composite sheet 30 in the hot pressing step shown in FIG. 7B will be described with reference to FIG. FIG. 8 is an enlarged cross-sectional view of a main part at the time of hot pressing shown in FIG. In the pressing process of the present embodiment, the rubber sheet 60 (60a, 60b) is compressed and deformed during pressing so as to wrap around the side surface 34 of the composite sheet 30 and cover the side surface 34 of the composite sheet 30. Yes.

  On the other hand, the pressed composite sheet 30 has a force to push it out of the substrate and tends to flow in the direction of the arrow 37. The composite sheet 30 that is about to flow in the direction of the arrow 37 is pushed back in the direction 65 in which the elastic force is exerted by the elastic force of the rubber sheet 60 (60a, 60b) that wraps around the side surface 34 of the composite sheet 30. As a result, the composite sheet 30 is pushed back to the inside of the substrate, and the flow that tries to protrude outside the substrate is suppressed.

  The side surface 34 of the composite sheet 30 may microscopically enter a gap between the rubber sheet 60 (60a, 60b), but even in this case, the rubber sheet 60 (60a, The side surface 34 of the composite sheet 30 does not need to be completely covered if it can be pushed back by the elastic force of 60b). For example, as shown in FIG. 9, the rubber sheets 60 (60a, 60b) It is sufficient that at least a part of the side surface 34 of the 30 is covered.

  In the example of FIG. 9, the rubber sheet 60 (60 a, 60 b) does not completely wrap around the side surface 34 during pressing, and a gap 38 is formed between the rubber sheet 60 (60 a, 60 b) and the side surface 34. However, since the rubber sheet 60 (60a, 60b) covers at least a part of the side surface 34, an elastic force works through the surface where the rubber sheet 60 (60a, 60b) and the side surface 34 are at least in pressure contact with each other. The composite sheet 30 that is about to flow out of the substrate is pushed back.

  The fluidity of the composite sheet 30 during pressing varies depending on the semi-cured state of the composite sheet 30, the press temperature (temperature increase rate, keep temperature), and the press pressure.

  For example, when the fluidity of the composite sheet 30 is low, the composite 30 tends to flow outside while maintaining a rectangular shape. Therefore, if a part of the rubber sheet 60 hits the side surface 34 of the composite 30, The side surface 34 moves integrally while maintaining a rectangular shape, and is pushed back to the inside of the substrate. Thus, the flow of the composite sheet 30 is reliably suppressed.

  On the other hand, when the fluidity of the composite sheet 30 is high, the composite sheet 30 flows into the gap 38 formed between the rubber sheet 60 (60a, 60b) and the side surface 34, but the rubber sheet 60 (60a , 60b), the composite sheet 30 that is about to flow out of the substrate can be pushed back, and the flow of the composite sheet 30 about to protrude outside is suppressed. As a result, it is possible to prevent the positional deviation of the inner via 33 formed at the end of the substrate.

  As described above, silicone rubber is used as the elastic member used in the present embodiment. As the hardness of the silicone rubber, suitable hardness for pushing back the composite sheet 30 with elastic force, and compression Thus, it is preferable to have an appropriate hardness that can be deformed and wrap around the side surface 34. For example, the suitable hardness of the rubber sheet 60 is A20 to A90 in the JIS 6253 standard and durometer type A test. Furthermore, since the pressing process of the present embodiment includes a heating process for curing the thermosetting resin (for example, a press temperature of 200 ° C.), silicone rubber is also suitable in that it is a material having high heat resistance.

  In this embodiment, silicone rubber is used as the elastic member. However, the present invention is not limited to this, and other materials having high heat resistance, for example, fluorine rubber can also be used as the elastic member. .

  The two rubber sheets 60a and 60b preferably have the same thickness (see FIG. 8: L60a = L60b). The advantage of this configuration is that the upper surface and the lower surface of the component built-in substrate 100 can be evenly pressurized, so that the warpage of the component built-in substrate 100 can be suppressed. As a result, it is possible to manufacture the component-embedded substrate 100 having a stable shape with little warpage while suppressing the displacement of the inner via 33. When the warpage of the component-embedded substrate 100 is large, the internal stress tends to accumulate, and the inner via 33 is likely to be defective in the reliability test.

  Furthermore, the total thickness of the two rubber sheets 60 (L60 = L60a + L60b) is equal to or greater than the sum of the thickness L10 of the first substrate 10, the thickness L20 of the second substrate 20, and the thickness L36 of the composite sheet 30. (L60 ≧ L10 + L20 + L30) is preferable. As a result, the two rubber sheets 60 can wrap the entire combination of the first substrate 10, the second substrate 20 and the composite sheet 30, so that the wraparound to the side surface 34 of the composite sheet 30 during pressing is ensured. The

  For example, in this embodiment, the thickness of the rubber sheets 60a and 60b is 1 mm, and the total thickness is 2 mm, whereas the total thickness of the first substrate 10, the second substrate 20, and the composite sheet 30 is combined. The thickness is 1 mm.

  The rubber sheet 60 used in the present embodiment has a flat shape, but is not limited to this. For example, as shown in FIG. 10, the rubber sheet 60 may have a concave shape. . In this example, the rubber sheet 60a is formed with a recess 62a for housing the first substrate 10, while the rubber sheet 60b is formed with a recess 62b for housing the second substrate 20.

  In the above configuration, since the first substrate 10 is accommodated in the recess 62a and the second substrate 20 is accommodated in the recess 62b, the rubber sheet 60 can reliably cover the side surface 34 of the composite sheet 30, as shown in FIG. It is possible to fill a space such as the gap 38 shown. In addition, since it is not necessary to increase the thickness of the rubber sheet 60 in consideration of the amount of rubber that wraps around the side surface 34 of the composite sheet 30, it is possible to reduce the thickness L62 of the pressing portion of the rubber sheet 60. is there. As a result, stable pressing can be performed.

  In the present embodiment, the case where the pressing is performed with the two rubber sheets 60 interposed between the upper die 50 and the second substrate 20 and between the lower die 40 and the first substrate 10 is mainly performed. However, the present invention is not limited to this. If the rubber sheet 60 covers the side surface 34 of the composite sheet 30 during pressing, the flow of the composite sheet 30 can be suppressed. it can.

  Therefore, for example, as shown in FIG. 11, the rubber frame 68 may be prepared and the press may be executed in a state where the rubber frame 68 is disposed so as to surround the composite sheet 30. In this configuration, the rubber frame 68 is not between the upper die 50 and the second substrate 20 and between the lower die 40 and the first substrate 10 but between the upper die 50 and the lower die 40. Although arranged, since the side surface 34 of the composite sheet 30 is covered, the flow of the composite sheet 30 is suppressed. The advantage of this configuration is that since it is configured with a stretchable rubber frame 68, high alignment accuracy is not required as compared with the case where the side surface 34 is covered with a special concave mold. In addition, even if the size of the rubber frame 68 and the size of the substrate do not match slightly, the rubber frame 68 can swell in a zigzag shape so that the composite sheet 30 can be surrounded. can do.

  In another example, one rubber sheet 60 is interposed between either the upper mold 50 and the second substrate 20 or between the lower mold 40 and the first substrate 10. A press may be performed. Even in this configuration, one rubber sheet 60 can be compressed and deformed during pressing and can wrap around the side surface 34 of the composite sheet 30, so that the flow of the composite sheet 30 can be suppressed.

  The conditions of the configuration shown in FIG. 7 are exemplarily shown as follows. The thickness of the composite sheet 30 is ensured to be high enough to contain the electronic component 12, and the thickness is, for example, 100 to 500 μm.

  As described above, the thickness of the rubber sheet 60 is preferably thicker than the total thickness of the first substrate 10, the second substrate 20, and the composite sheet 30, and the thickness is, for example, 2 mm in total. It is. Moreover, the size of the rubber sheet 60 is required to be large enough to contain the component-embedded substrate 100. The size is, for example, 120 × 120 mm with respect to a 100 × 100 mm substrate. The rubber sheet 60 is silicone rubber and has a hardness of A50 in the JIS 6253 standard and durometer type A test.

  The thermosetting resin included in the composite sheet 30 of the present embodiment is, for example, an epoxy resin, a phenol resin, a cyanate resin, a polyphenylene ether resin, or a mixture thereof.

The inorganic filler is, for example, Al ₂ O ₃ , SiO ₂ , MgO, BN, AlN or the like. Since various physical properties can be controlled by adding the inorganic filler, for example, the heat generation of the built-in electronic component 12 can be diffused well. The inorganic filler contained in the composite sheet 30 is, for example, 70 to 95% by weight.

The role of the inorganic filler will be further described as follows. When Al ₂ O ₃ , BN, or AlN is added as the inorganic filler, the thermal conductivity of the component built-in substrate can be improved. In addition, the thermal expansion coefficient can be adjusted by selecting an appropriate inorganic filler. Since the thermal expansion coefficient is relatively large due to the resin component, the thermal expansion coefficient can be reduced by adding SiO ₂ or AlN. In some cases, addition of MgO can increase the thermal expansion coefficient while improving the thermal conductivity. Further, SiO ₂ (in particular, amorphous SiO ₂₎ if both can be reduced thermal expansion coefficient, it is possible to lower the dielectric constant.

  In the manufacturing method of the present embodiment, a large number of component-embedded substrates can be configured at the same time. In FIG. 12, a plurality of electronic components 12 are mounted on one first substrate 10, and the first substrate 10 includes a plurality of substrate blocks 70 that serve as units of individual component-embedded substrates 100. This is an example (in the example of FIG. 12, nine substrate blocks 70 are included). In this example, the first substrate 10, the second substrate 20, and the composite sheet 30 are stacked, sandwiched between upper and lower press plates and subjected to hot pressing, and then further cut into individual substrate blocks 70. Process.

  Even in such a multi-chip substrate, since the side surface 34 of the composite sheet 30 is covered with the rubber sheet 60, the flow of the composite sheet 30 can be suppressed, and the inner via 33 is formed. It is possible to reduce the area that cannot be done (via prohibited area). In addition, since a plurality of component-embedded substrates 100 can be manufactured at once, productivity is improved. Furthermore, as described above, when the via-prohibited area cannot be completely eliminated, it is necessary to cut the via-prohibited area after crimping with a hot press. Since the ratio of the via-prohibited area occupying the entire substrate area is lower than that of the single-sided substrate, the productivity is improved as compared with the single-sided substrate.

  In addition, as shown in FIG. 13, a plurality of combinations (substrate combinations 80) of the first substrate 10, the second substrate 20, and the composite sheet 30 are prepared and arranged on the same plane. It is also possible to execute pressing collectively using upper and lower press plates.

  Thus, even when a plurality of substrate combinations 80 are pressed together, the compressed and deformed rubber sheet 60 covers the side surface 34 of each substrate combination 80. In the body 80, the flow of the composite sheet 30 can be suppressed, and the area where the inner via 33 cannot be formed (via prohibited area) can be reduced. In addition, even when the thicknesses of the substrate combinations 80 are different, the rubber sheet 60 that is compressed and deformed by utilizing the elasticity of rubber is used to form the side surfaces 34 of the individual substrate combinations 80. Can be pressed at the same time. As a result, productivity is further improved.

  Furthermore, as shown in FIG. 14, this embodiment can be applied to a multi-stage component-embedded substrate 100. First, the first substrate 10 on which the electronic component 12 (12a, 12b) is mounted and the second substrate 20 provided to face the first substrate are electrically connected to the first substrate 10 and the second substrate 20. Lamination is performed via the composite sheet 30 in which the inner via 33 for securing the connection is formed. Further, the third substrate 90 is laminated on the second substrate 20 via another upper composite sheet 35.

  Next, pressing is performed by sandwiching the first substrate 10, the second substrate 20, and the third substrate 90 with the composite sheets 30 and 35 interposed therebetween by the upper mold 50 and the lower mold 40.

  In this pressing step, two rubber sheets 60 (60a, 60b) are interposed between the upper die 50 and the third substrate 90 and between the lower die 40 and the first substrate 10, The rubber sheet 60 is compressed and deformed, and wraps around the side surfaces of the composite sheets 30 and 35, thereby configuring a state covering the side surfaces. Therefore, since the flow of the upper composite sheet 35 in addition to the composite sheet 30 can be suppressed, displacement of the inner via 33 is prevented at any stage.

  As mentioned above, although this invention was demonstrated by suitable embodiment, such description is not a limitation matter and of course, various modifications are possible.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of a component built-in board | substrate with favorable productivity can be provided.

A perspective view schematically showing a configuration of a conventional component-embedded substrate 400 Plan view to explain the effect of board area reduction by the component built-in board technology (A) to (d) are process cross-sectional views for explaining a conventional method for manufacturing a component-embedded substrate 400. (A) is a sectional view before the LSI chip 403a is embedded in the composite sheet, and (b) is a sectional view for explaining a state when the LSI chip 403a is embedded in the composite sheet. (A) is a cross-sectional view before embedding an LSI chip in a composite sheet, and (b) is a cross-sectional view for explaining the state of the substrate end when the LSI chip is embedded in a composite sheet. (A) is a top view for explaining the proportion of the via-prohibited area 210 in the whole substrate in the multi-piece substrate, and (b) is the proportion of the via-prohibited area 210 in the whole substrate in the individual substrate. Top view explaining (A), (b) is process sectional drawing which shows typically the manufacturing process of the component built-in board | substrate 100 which concerns on embodiment of this invention. The principal part expanded sectional view at the time of the press shown in FIG.7 (b) The principal part expanded sectional view at the time of the press for demonstrating the case where the rubber sheet 60 covers a part of side surface 34 of the composite sheet 30 (A) is sectional drawing shown about the structure of the rubber sheet 60 which is a concave shape, (b) is sectional drawing shown about the structure at the time of the press in case the rubber sheet 60 is concave shape. Sectional drawing shown about the structure at the time of a press at the time of using the rubber frame 68 (A) is a plan view showing the configuration at the time of pressing a multi-piece substrate, (b) is a cross-sectional view showing the configuration at the time of pressing a multi-piece substrate (A) is sectional drawing which shows the piece of a board | substrate, (b) is sectional drawing shown about the structure at the time of pressing the board | substrate of several piece separation simultaneously. Sectional drawing which shows the structure at the time of the press of the board | substrate of a multistage structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 1st board | substrate 12 Electronic component 12a Semiconductor element 12b Passive component 20 2nd board | substrate 30 Resin intervening layer (composite sheet)
32 Interlayer connection member (inner via)
33 Interlayer connection member (inner via) formed at the edge of the substrate
34 Composite sheet 30 side surface 35 Upper composite sheet 40 Lower mold 50 Upper mold 60 Elastic member (rubber sheet)
65 direction in which the elastic force works 68 rubber frame 70 board block that is a unit of the component built-in substrate 100 80 substrate combination 90 third substrate 100 component built-in substrate 150 press direction 210 via prohibited area 200 via effective area 400 component incorporated Board (module with built-in circuit components)
500 Circuit board

Claims (12)

A method of manufacturing a component-embedded substrate in which electronic components are embedded in a substrate,
An interlayer connection member that secures an electrical connection between the first substrate and the second substrate is formed between the first substrate on which the electronic component is mounted and the second substrate provided to face the first substrate. Laminating via the resin interposed layer,
A step (b) of pressing the first substrate and the second substrate with the resin intervening layer interposed between an upper mold and a lower mold,
In the step (b), an elastic member is interposed between the upper die and the lower die, and the pressing is performed in a state where the elastic member covers at least a side surface of the resin intervening layer during pressing. A method for manufacturing a component-embedded substrate. In the step (b), the elastic member is interposed between the upper mold and the second substrate, and between the lower mold and the first substrate,
The method for manufacturing a component-embedded substrate according to claim 1, wherein the elastic member wraps around a side surface of the resin intervening layer during the pressing. The method of manufacturing a component built-in substrate according to claim 2, wherein an outer shape of the elastic member is larger than an outer shape of the first substrate and the second substrate. 2. The method of manufacturing a component-embedded board according to claim 1, wherein in the step (b), the side surface of the resin intervening layer is pushed back by an elastic force of the elastic member. The elastic member is a rubber sheet made of silicone rubber,
The rubber sheet is composed of a first sheet interposed between the lower mold and the first substrate, and a second sheet interposed between the upper mold and the second substrate. 5. A method for manufacturing a component-embedded board according to any one of 1 to 4. The sum of the thickness of the first sheet and the thickness of the second sheet is equal to or greater than the sum of the thickness of the first substrate, the thickness of the second substrate, and the thickness of the resin intervening layer. A method for manufacturing a component-embedded board as described in 1. The method for manufacturing a component-embedded board according to claim 5 or 6, wherein the thickness of the first sheet and the thickness of the second sheet are the same. The concave portion for accommodating the first substrate is formed in the first sheet, while the concave portion for accommodating the second substrate is formed in the second sheet. The manufacturing method of the component built-in board | substrate as described in any one. The resin intervening layer is composed of a composite sheet containing at least a thermosetting resin and an inorganic filler,
The method for manufacturing a component-embedded substrate according to claim 1, wherein in the step (b), the electronic component is embedded in the composite sheet. The first board on which the electronic component is mounted includes a plurality of board blocks that are units of individual component-embedded boards,
The method for manufacturing a component-embedded substrate according to claim 1, further comprising a step of cutting into the individual substrate blocks after the step (b). In the step (a), a plurality of substrate combinations in which the first substrate, the second substrate, and the resin intervening layer are combined are prepared,
The method for manufacturing a component-embedded board according to claim 1, wherein in the step (b), the plurality of board combinations are pressed together in the same process. In the step (a), a third substrate is further laminated on the second substrate via a resin intervening layer,
2. In the step (b), the first substrate, the second substrate, and the third substrate with the resin intervening layer interposed therebetween are sandwiched and pressed between an upper die and a lower die. To 11. The method for manufacturing a component-embedded substrate according to any one of items 1 to 11.

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