KR20130120390A - Wiring board, mounting structure, method of manufacturing wiring board and method of manufacturing mounting structure - Google Patents

Abstract

The wiring board 4 of the present invention includes a core board 7 and a first build-up layer 8a positioned on the core board 7 and on which an electronic component 2 is mounted on an upper surface thereof. The core board 7 And a plurality of power supply through-hole conductors 10P penetrating the silver substrate 9 and the substrate 9 in the thickness direction, and the first build-up layer 8a includes an insulating layer 11 having a smaller thickness than the substrate 9; A plurality of power supply pads 14P electrically connected to the power supply terminal 6P and the power supply through-hole conductor 10P of the electronic component 2 and formed on the insulating layer 11, and the insulating layer 11 And a plurality of power supply via conductors (13P) for electrically connecting the power supply through-hole conductor (10P) and the power supply pad (14P) to the thickness direction, and a set of power supply pads (14P) electrically connected thereto; and In the power supply through hole conductor 10P, the number of power supply through hole conductors 10P is larger than the number of power supply pads 14P.

Description

WIRING BOARD, MOUNTING STRUCTURE, METHOD OF MANUFACTURING WIRING BOARD AND METHOD OF MANUFACTURING MOUNTING STRUCTURE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board, a mounting structure, a method of manufacturing a wiring board, and a method of manufacturing the mounting structure used in electronic devices such as various audio visual devices, home appliances, communication devices, computer devices, peripheral devices, and the like.

Background Art Conventionally, an electronic component mounted on a wiring board is used as a mounting structure in an electronic device.

Japanese Laid-Open Patent Publication No. 2004-134679 includes a plurality of build-up layers on both sides of a core substrate, and the core substrate includes a charge-through hole portion which becomes part of a signal line in a semiconductor package, and a power line or ground line in a semiconductor package. A wiring board having a plated-through hole portion to be a part is disclosed.

However, in recent years, there is a demand for power saving of electronic devices, and there is a demand for lowering power consumption of semiconductor chips. Since this power consumption is proportional to the voltage of the power supply of the semiconductor chip, it is necessary to lower the power supply voltage in order to reduce the power consumption.

However, when the voltage of the power supply of the semiconductor chip is lowered, the influence of voltage fluctuations due to the impedance and inductance of the power supply line on the wiring board becomes larger, and the semiconductor chip is more likely to malfunction. Therefore, it is required to operate the semiconductor chip with high reliability.

SUMMARY OF THE INVENTION The present invention provides a wiring board, a mounting structure, a manufacturing method of a wiring board, and a manufacturing method of the mounting structure that meet the demand for operating electronic components with high reliability.

The wiring board of the present invention includes a build-up layer on which the electronic component is mounted on the core board and the core board, and the core board includes a plurality of power supply through-hole conductors that penetrate the body and the body in the thickness direction. The build-up layer has an insulating layer having a thickness smaller than that of the substrate, a plurality of power pads electrically connected to the power terminal and power through-hole conductor of the electronic component, and formed on the insulating layer, and penetrating the insulating layer in the thickness direction. And a plurality of power supply via conductors for electrically connecting the power supply through hole conductor and the power supply pad, wherein the number of the power supply through hole conductors in the set of electrically connected power supply pads and the power supply through hole conductor is It is characterized by more than the number of pads for the power supply.

(Effects of the Invention)

According to the wiring board of this invention, the number of through-hole conductors for power supply is larger than the number of pads for power supply in one set of electrically connected pads for power supply and through-hole conductors for power supply. Therefore, the path through which the electric current for a power supply flows in a core board | substrate can be increased in parallel, the impedance and inductance of the through-hole conductor for a power supply in a core board | substrate can be reduced, and an electronic component can operate reliably. .

Fig. 1A is a side view of the mounting structure according to the embodiment of the present invention, and Fig. 1B is a top view of the mounting structure according to the embodiment of the present invention.
It is an enlarged view of the cross section cut | disconnected along the AA line in the thickness direction in the P1 part of FIG.
FIG. 3 is an enlarged view of a section cut along the line BB in the thickness direction in the portion P1 in FIG. 1 (b).
FIG. 4A is an enlarged view of a cross section taken along the CC line of FIG. 2 in the plane direction in the portion P1 of FIG. 1B, and FIG. 4B is a portion P1 of FIG. 1B. It is an enlarged view of the cross section cut along the DD line of FIG. 2, and FIG. 4 (c) is the cross section cut along the E-E line of FIG. 2 in the P1 part of FIG. It is an enlarged view.
FIG. 5 is an enlarged view of a cross section corresponding to FIG. 2 illustrating a manufacturing process of the mounting structure shown in FIG. 1A. FIG.
It is an enlarged view of the cross section corresponded to FIG. 2 explaining the manufacturing process of the mounting structure shown to FIG. 1 (a).

EMBODIMENT OF THE INVENTION Hereinafter, the mounting structure containing the wiring board which concerns on one Embodiment of this invention is demonstrated in detail based on drawing.

The mounting structure 1 shown in FIG.1 (a) and FIG.1 (b) is used for electronic devices, such as various audio visual equipment, home appliances, a communication device, a computer device, or its peripheral equipment, for example. This mounting structure 1 includes the flat-shaped electronic component 2 and the flat-shaped wiring board 4 in which the electronic component 2 was flip-chip mounted via the bump 3.

The electronic component 2 is, for example, a semiconductor element such as an IC or LSI, and as shown in FIGS. 2 and 3, a flat semiconductor substrate 5 and a disk shape formed on the bottom surface of the semiconductor substrate 5. A plurality of terminals 6 are included. The semiconductor substrate 5 is formed of semiconductor materials, such as silicon, germanium, gallium arsenide, gallium arsenide phosphorus, gallium nitride, or silicon carbide, for example. The terminal 6 may be formed of a conductive material such as copper, gold, aluminum, nickel or chromium, for example. Among these, it is preferable to use copper from a viewpoint of electroconductivity.

As shown in FIGS. 2 and 3, the plurality of terminals 6 include a plurality of power supply terminals 6P for supplying power to the semiconductor substrate 5 and a plurality of grounds for connecting the semiconductor substrate 5 to ground potential. The terminal 6G and a plurality of signal terminals (not shown) for inputting and outputting signals to and from the semiconductor substrate 5 are included.

Here, the lower surface of the electronic component 2 includes a first region R1 located in the center portion and a second region R2 positioned near the outer circumference of the electronic component 2 and surrounding the first region R1. It is included. A plurality of power supply terminals 6P and a plurality of ground terminals 6G are disposed in the first region R1, and a plurality of signal terminals are disposed in the second region R2.

In the first region R1, the plurality of terminals 6 are arranged in a lattice shape, for example. As the power supply terminal 6P and the ground terminal 6G are alternately positioned, the plurality of power supply terminals 6P are arranged in a zigzag shape, and the plurality of ground terminals 6G are also arranged in a zigzag shape. In this case, the pitch of the some terminal 6 in 1st area | region R1 is set to 200 micrometers or more and 250 micrometers or less, for example. In addition, in the 1st area | region R1, the some terminal 6 does not need to be arrange | positioned in grid | lattice form. The pitch of the some terminals 6 is obtained by measuring the distance between the centers of each of the adjacent terminals 6 in the cross section cut | disconnected in the thickness direction. Hereinafter, the pitch of each member is also obtained similarly to the pitch of the terminal 6.

In the second region R2, a plurality of signal terminals are arranged in a lattice shape, for example. The pitch of the some terminals 6 in 2nd area | region R2 is set smaller than the pitch of the some terminal 6s in 1st area | region R1. The pitch of the some terminal 6 in 2nd area | region R2 is set to 128 micrometers or more and 180 micrometers or less, for example.

The bump 3 is comprised with electrically-conductive materials, such as solder containing lead, tin, silver, gold, copper, zinc, bismuth, indium, aluminum, etc., for example.

The wiring board 4 electrically connects the electronic component 2 and the motherboard (not shown), and the electronic component 2 is mounted on the upper surface, and the lower surface is mounted on the motherboard through ball bumps (not shown). do. The wiring board 4 includes a flat core board 7 and a pair of buildup layers 8 formed on both sides of the core board 7.

The core board 7 achieves conduction between the pair of build-up layers 8 while increasing the strength of the wiring board 4. The core substrate 7 includes a flat base body 9 having a plurality of cylindrical through holes penetrating in the thickness direction, and a through hole conductor 10 filled in the plurality of through holes.

The base 9 increases the rigidity of the core substrate 7 and includes, for example, a resin such as a glass cloth and an epoxy resin covering the glass cloth. The silica filler is dispersed in the resin. The thickness of the base 9 is set to 0.4 mm or more and 1.2 mm or less, for example. In addition, the thickness of the base 9 is larger than the thickness of the insulating layer 11 mentioned later, and is larger than the thickness of one buildup layer 8.

The through-hole conductor 10 electrically connects the buildup layers 8 above and below the core substrate 7, and is formed of a conductive material such as copper, aluminum, or nickel, for example. Among these, it is preferable to use copper with high electroconductivity. The plurality of through hole conductors 10 are arranged in a lattice shape. The pitch of the plurality of through hole conductors 10 is smaller than the pitch of the terminals 6 in the first region R1. In addition, the pitch of some through-hole conductors 10 is set to 100 micrometers or more and 180 micrometers or less, for example.

The through hole conductor 10 is electrically connected to the bump 3 and the terminal 6 via the via conductor 13 and the pad 14 described later. The plurality of through hole conductors 10 include a plurality of power supply through hole conductors 10P electrically connected to the power supply terminal 6P, and a plurality of ground through hole conductors 10G electrically connected to the ground terminal 6G. ) And a plurality of signal through hole conductors (not shown) electrically connected to the signal terminals.

On the other hand, a pair of buildup layers 8 are formed on both sides of the core substrate 7 as described above. The buildup layer 8 functions as a multilayer wiring layer for drawing wirings while increasing the wiring density. The build-up layer 8 is laminated on the substrate 9 and has an insulating layer 11 having via holes penetrating in the thickness direction, and a conductive layer 12 formed on the substrate 9 or on the insulating layer 11. ), A via conductor 13 filled in the via hole and electrically connected to the conductive layer 12, and a bump disposed on the uppermost insulating layer 11 and electrically connected to the via conductor 13. The pad 14 to which 3 is connected is included. In the present embodiment, one build-up layer 8 includes three insulating layers 11.

For convenience, the one arranged on the electronic component 2 side of the pair of build up layers 8 is referred to as the first buildup layer 8a, and the one arranged on the motherboard side is referred to as the second buildup layer 8b.

The insulating layer 11 functions not only as a supporting member for supporting the conductive layer 12 but also as an insulating member for preventing short circuits between the conductive layers 12. The insulating layer 11 contains resin, such as an epoxy resin in which the silica filler etc. were disperse | distributed. The thickness of the insulating layer 11 is set smaller than that of the base 9, and as a result, the rigidity of the wiring board 4 can be increased by the base 9 while densifying the wiring in the buildup layer 8. have. The thickness of the insulating layer 11 is set to 20 micrometers or more and 40 micrometers or less, for example.

For convenience, the first insulating layer 11a, the second insulating layer 11b, and the third insulating layer of the three insulating layers 11 included in the first build-up layer 8a are sequentially placed from the base 9 side. It is set as 11c (topmost layer).

The conductive layer 12 functions by wiring and is formed of metal materials, such as copper, silver, gold, aluminum, nickel, or chromium, for example. Among these, it is preferable to use copper from a viewpoint of electroconductivity. The thickness of this conductive layer 12 is set to 10 micrometers or more and 25 micrometers or less, for example.

For convenience, the names of the layers on which the conductive layer 12 is formed are named FC1, FC2, and FC3 from the upper surface of the base 9 to the upper surface of the wiring board 4, and the wiring board ( It is set as BC1, BC2, and BC3 toward the lower surface of 4).

The conductive layer 12 includes a plurality of power conductive layers 12P electrically connected to the power supply terminal 6P, a plurality of ground conductive layers 12G electrically connected to the ground terminal 6G, and a signal terminal. A plurality of signal conductive layers (not shown) electrically connected to the circuit board are included. The power supply conductive layer 12P and the ground conductive layer 12G include a solid layer formed in a solid shape. The solid layer of the power supply conductive layer 12P and the solid layer of the ground conductive layer 12G are alternately arranged. In the first build-up layer 8a, as shown in FIGS. 2, 4A, and 4B, the solid layer FC1 of the conductive layer 12G for ground and the power supply are formed from the upper surface of the base 9. It is formed in order of the solid layer FC2 of the conductive layer 12P and the solid layer FC3 of the conductive layer 12G for ground. In the second build-up layer 8b, as shown in FIGS. 2 and 4 (c), the solid layer BC1 of the power supply conductive layer 12P and the ground conductive layer 12G are formed from the lower surface of the base 9. It is formed in the order of the solid layer BC2 and the solid layer BC3 of the power supply conductive layer 12P.

The via conductors 13 mutually connect the conductive layers 12 spaced apart from each other in the thickness direction, and are formed of a metal material such as copper, silver, gold, aluminum, nickel, or chromium. Among these, it is preferable to use copper from a viewpoint of electroconductivity. The via conductor 13 is formed in a tapered shape in which the upper and lower surfaces are circular and the diameter becomes smaller toward the core substrate 7.

The via conductor 13 includes a plurality of power supply via conductors 13P electrically connected to the power supply terminal 6P, a plurality of ground via conductors 13G electrically connected to the ground terminal 6G, A plurality of signal via conductors (not shown) are electrically connected to the signal terminals.

The pad 14 functions as a terminal for electrically connecting the electronic component 2, and is formed of, for example, a metal material such as copper, silver, gold, aluminum, nickel, or chromium. Among these, it is preferable to use copper from a viewpoint of electroconductivity. This pad 14 is formed in disk shape, for example. The thickness of this pad 14 is set to 10 micrometers or more and 25 micrometers or less, for example.

The pad 14 is electrically connected to a plurality of power supply pads 14P electrically connected to a power supply terminal 6P, a plurality of grounding pads 14G electrically connected to a grounding terminal 6G, and a signal terminal. A plurality of signal pads (not shown) to be connected are included. These pads 14 are arranged similarly to the terminals 6 to be connected, respectively.

In the wiring board 4 described above, the plurality of power supply through-hole conductors 10P, the plurality of power supply conductive layers 12P, the plurality of power supply via conductors 13P, and the plurality of power supply pads 14P are electrically connected to each other. This constitutes one set of power supply wirings, and only one set of power supply wirings is formed on the wiring board 4. In this power supply wiring, a plurality of power supply through-hole conductors 6P or a plurality of power supply via conductors 13P are electrically connected to each other by a solid layer of the power supply conductive layer 12P.

Similarly, the plurality of ground through-hole conductors 10G, the plurality of ground conductive layers 12G, the plurality of ground via conductors 13G, and the plurality of ground pads 14G are electrically connected to each other in one set. Ground wiring, and only one set of ground wiring is formed on the wiring board 4. In the ground wiring, a plurality of ground through-hole conductors 6G or a plurality of ground via conductors 13G are electrically connected to each other by a solid layer of the ground conductive layer 12G.

In addition, the signal through hole conductor, the signal conductive layer of each layer, the signal via conductor of each layer, and the signal pad are electrically connected to each other one by one to constitute a set of signal wirings on the wiring board 4, In the wiring board 4, a plurality of sets of signal wirings are formed.

By the way, the thickness of the base body 9 in the core substrate 7 is larger than the thickness of the insulating layer 11 of the buildup layer 8. Therefore, the impedance and inductance in the through-hole conductor 10P for power supply which penetrates the base body 9 in the thickness direction are the impedance and inductance in the via conductor 13P for power supply which penetrates the insulating layer 11 in the thickness direction. Easier to grow

In this embodiment, as shown in FIG. 2, the power supply through-hole conductor 10P in one set of power supply pads 14P and the power supply through-hole conductor 10P, that is, one set of power supply wiring. Is larger than the number of the pads 14P for power supply. As a result, by increasing the number of through-hole conductors 10P for power supply, the path through which current for power flows in the core substrate 7 is increased in parallel, so that the through-hole conductor 10P for power supply in the core substrate 7 is increased. Impedance and inductance can be reduced. Therefore, the voltage in the power supply wiring can be stabilized and the electronic component 2 can be operated with high reliability. In addition, the number of through-hole conductors 10P for power supply is set to 2 times or more and 4 times or less of the number of the pads 14P for power, for example.

In the one set of power supply pads 14P, the via via conductor 13P and the through-hole conductor 10P for power supply, that is, the set of power supply through-hole conductors 10P, the number of through-hole conductors 10P for power supply is on the uppermost layer. There is more than the number of via conductors 13P for power supply which penetrate the 3rd insulating layer 11c located. As a result, the voltage in the power supply wiring can be effectively stabilized by reducing the impedance and inductance in the power supply through-hole conductor 10P penetrating the substrate 9 having a larger thickness than the third insulating layer 11c in the thickness direction. Can be.

In the present embodiment, the number of power supply via conductors 13P penetrating through the third resin layer 11c is the same as the number of power supply pads 14P, and the power supply via conductors 13P penetrating through the third resin layer 11c. Are respectively connected to the power pad 14P.

In addition, in this embodiment, the number of via conductors 13P for power supply penetrating the 1st resin layer 11a is equal to the number of through-hole conductors 10P for power supply, and penetrates the 1st resin layer 11a. The via via conductor 13P for power supply is connected to the through-hole conductor 10P for power supply, respectively. In the conductive layer 12 (FC2) on the first resin layer 11a, the via via conductor 13P for power passing through the first resin layer 11a is electrically connected to each other in the solid layer of the power conductive layer 12P. Connected. A power supply via conductor 13P is connected to the solid layer of the power supply conductive layer 12P, which penetrates the second resin layer 1lb. The number of power supply via conductors 13P penetrating the second resin layer 1lb is smaller than the number of power supply via conductors 13P penetrating the first resin layer 11a, and the third resin layer 11c is provided. It is equal to the number of via conductors 13P for the power supply passing through. The power supply via conductor 13P penetrating the second resin layer 1lb is connected to the power supply via conductor 13P penetrating the third resin layer 11c. In addition, you may change suitably the number of via conductors 13P for power supply in each layer.

In addition, in this embodiment, the power supply through hole conductor 10P is filled in the through hole for power supply which penetrated the base 9P in the thickness direction. As a result, the impedance and inductance in one through-hole conductor 10P for power supply can be reduced.

In the present embodiment, the number of ground through-hole conductors 10G in one set of ground pads 14G and ground through-hole conductors 10G that are electrically connected to each other is that of the ground pads. More than the number of (14G). As a result, the voltage can be stabilized in the ground wiring as well as the power supply wiring, and the electronic component 2 can be operated with high reliability.

Ground through-hole conductor 10G in one set of ground pads 14G, ground via conductor 13G and ground through-hole conductor 10G that are electrically connected, that is, in one set of grounding wiring. Is larger than the number of ground via conductors 13G penetrating through the third insulating layer 11c positioned on the uppermost layer. As a result, the voltage in the ground wiring is effectively reduced by reducing the impedance and inductance in the through-hole conductor 10G for ground which penetrates the base body 9 having a larger thickness than the third insulating layer 11c in the thickness direction. It can stabilize.

In the present embodiment, the number of ground via conductors 13G penetrating through the third resin layer 11c is equal to the number of pads 14G for ground, and the ground penetrating through the third resin layer 11c is used. The via conductor 13G is connected to the ground pad 14G, respectively.

In the present embodiment, the ground through-hole conductor 10G is electrically connected to each other in the solid layer of the ground conductive layer 12G in the conductive layer 12 (FC1) on the substrate 9. And the ground via conductor 13G which penetrates the 1st resin layer 11a is connected to the solid layer of the ground conductive layer 12G. The number of ground via conductors 13G penetrating through the first resin layer 11a is smaller than the number of ground through-hole conductors 10G, and the ground via conductors 13G penetrate the second resin layer 1lb. ), The number of ground via conductors 13G penetrating through the third resin layer 11c, and the number of ground pads 14G. The number of ground via conductors 13G in each layer may be appropriately changed.

On the other hand, the number of signal through hole conductors in one set of signal pads and signal through hole conductors electrically connected, that is, in one set of signal wirings, is equal to the number of signal pads. As a result, the signal pad and the signal through hole conductor can be connected one-to-one, and the signal can be transmitted well in the signal wiring.

In this way, the mounting structure 1 described above exhibits a desired function by driving or controlling the electronic component 2 based on a power source or a signal supplied through the wiring board 4.

Next, the manufacturing method of the mounting structure 1 mentioned above is demonstrated based on drawing.

(1) As shown in FIG. 5, a core substrate 6 is produced. Specifically, it is performed as follows.

The copper clad laminated board which consists of the base body 9 which hardens an uncured resin sheet, and the copper foil arrange | positioned above and below the said base body 9 is prepared. Subsequently, through holes are formed in the copper-clad laminate 5x by sandblasting. Subsequently, the through-hole conductor 10 is formed by filling a conductive material in the through hole by, for example, an electroless plating method, an electrolytic plating method, a vapor deposition method, a CVD method, or a sputtering method. Next, the copper foil on the base 9 is patterned by conventionally well-known photolithography technique, an etching, etc., and the conductive layer 12 is formed. In this manner, the core substrate 7 can be produced.

Here, the formation method of the through hole using the sand blasting process is demonstrated in detail.

First, resists with openings are formed on both sides of the copper-clad laminate to form through holes. This resist can be formed by exposure and development of the photosensitive resin, for example. Subsequently, a part of the through hole (non-penetrating) is formed through the opening of the resist by injecting the fine particles from the nozzle of the sand blasting apparatus to one main surface of the copper clad laminate. Next, through-holes penetrating the substrate 9 are formed by injecting the fine particles onto the other peripheral surface of the copper-clad laminate. In addition, the through hole which penetrates the base 9 may be formed by spraying microparticles only to the one main surface of a copper clad laminated board. The resist is then removed, for example, with 1 to 3 wt% sodium hydroxide solution. Subsequently, the inner wall of the through hole is washed with high pressure to remove the remaining fine particles and processing chips of the through hole. As described above, the through hole can be formed by sandblasting.

Thus, when the sand blasting method is used, since through holes are formed by the injection of fine particles, the stress and heat applied to the boundary between the glass cloth and the resin can be reduced as compared with the drilling process. Moreover, compared with laser processing, the heat applied to the boundary of glass cloth and resin can be reduced. Therefore, when sandblasting method is used, peeling of glass cloth and resin can be reduced compared with drill processing and laser processing. Therefore, the space | interval can be narrowed, reducing the short circuit of adjacent through-hole conductors 10, and can narrow the through-hole conductor 10. FIG. As a result, as described above, the power supply through hole conductor 10P can be narrowed as compared with the power supply pad 14P, and the number of the power supply through hole conductors 10P can be larger than the number of the power supply pads 14P. In addition, as in the power supply through hole conductor 10P, the number of ground through hole conductors 10G can be made larger than the number of ground pads 14G.

Since sand blasting is performed using a resist, a plurality of through holes can be processed at the same time by spraying fine particles in a wide range, so that the through holes can be efficiently formed as compared with drill processing or laser processing. Therefore, even if the number of through holes is increased, an increase in machining time and the like can be suppressed.

When the sand blasting process is used, when the content of the silica filler in the base 9 is increased, the drill is not worn like the drill process and the through hole can be formed more easily than the laser machining.

Since through holes are formed by sand blasting as described above, sand blasting can be performed under the following conditions.

First, sand blasting is performed by dry blasting. As a result, since the resistance to microparticles | fine-particles is small compared with a wet blast, it is possible to improve the cutting property of a through hole, to reduce the residue of the processing waste at the time of cutting, and to reduce the cutting inhibition by the said processing waste.

As microparticles | fine-particles sprayed from a sand blast, the crushed microparticles | fine-particles (crushed particle) which consist of an inorganic insulating material whose hardness is higher than glass can be used. As a result, the glass cloth exposed to the inner wall of the through hole can be efficiently cut by the sharp end of the crushed particles harder than the glass cloth, so that the through hole can be efficiently formed while reducing the stress applied between the glass cloth and the resin. have. As the inorganic insulating material having a higher hardness than glass in this manner, for example, alumina, silicon carbide, zirconia, or the like can be used. Among these, it is preferable to use alumina. As the hardness, Vickers hardness can be used.

The microparticles | fine-particles are set to 3 micrometers or more and 40 micrometers or less in the largest diameter of a crushed particle. As a result, by making the maximum diameter 3 micrometers or more, the cutting property by a crushed particle can be improved and a through hole can be formed easily. Further, by setting the maximum diameter to 40 μm or less, the crushed particles can form through holes without blocking the holes.

It is preferable that the pressure which injects microparticles | fine-particles is set to 0.15 MPa or more and 0.22 MPa or less. As a result, the glass cloth in a through hole can be cut efficiently by setting pressure to 0.15 MPa or more. Furthermore, by setting the pressure to 0.22 MPa or less, the crushed particles can be processed so that the resin of the through-hole inner wall is not cut excessively.

It is preferable that the injection amount of microparticles | fine-particles is set to 30 g / min or more and 200 g / min or less. As a result, the glass cloth in a through hole can be cut efficiently by making injection amount into 30 g / min or more. In addition, by setting the injection amount to 200 g / min or less, the crushed particles can be processed so as to prevent the resin of the through-hole inner wall from being excessively cut.

The number of times (the number of scans) of injecting the fine particles into one through hole is set to, for example, 4 times or more and 20 times or less when the thickness of the core substrate 7 is 40 µm or more and 200 µm or less.

As for the gas 9 which injects microparticles | fine-particles, the content rate of a silica filler is set to 40 volume% or more and 75 volume% or less. As a result, the cutting property of the resin layer 15 by sandblasting can be improved by making content rate of a silica filler into 40 volume% or more. In addition, when the content ratio of the silica filler is 75 vol% or less, when the through hole is formed, the detachment of the silica filler from the through hole inner wall is reduced, and bubbles remain in the pit resulting from the detachment, so that the through hole inner wall and the conductive layer It can reduce that the adhesive strength of (12) falls. In addition, the content rate of a silica filler is obtained by calculating the ratio of the volume of a silica filler with respect to the sum total of the volume of resin and a silica filler in the area which does not contain the glass cloth of the base 9.

Here, it is preferable that the inner wall of the through hole formed by sandblasting processing does not perform a desmear process. When through-holes are formed by sand blasting, heat applied to the inner wall of the through-holes can be reduced in comparison with drill processing or laser processing to reduce the residue of carbonized resin. In addition, since the bond between molecules is physically broken, the reaction activity of the surface of the resin exposed on the through-hole inner wall can be enhanced. By not performing a desmear process in this way, only resin can be etched selectively and the exposure of the side surface of a glass cloth is largely exposed, and peeling of resin and glass cloth can be reduced.

(2) As shown in FIG. 6, the wiring board 4 is produced by forming a pair of buildup layers 8 on both sides of the core substrate 7. Specifically, it is performed as follows.

First, the uncured resin is disposed on the conductive layer 12, and the insulating layer 11 is formed on the conductive layer 12 by heating the resin while heating and fluidly contacting the resin, and curing the resin. Next, via holes are formed by laser processing, and at least a portion of the conductive layer 12 is exposed in the via holes. Thus, by forming the via hole by laser processing, damage to the conductive layer 12 exposed in the via hole can be reduced as compared with sand blasting. Subsequently, the via conductor 13 is formed in the via hole by, for example, a semiadditive method, a subtractive method, or a full additive method, and the conductive layer 12 is formed on the upper surface of the insulating layer 11. . By repeating the above process, the buildup layer 8 can be formed. In addition, the pad 14 can be formed on the upper surface of the insulating layer 11 of the uppermost layer similarly to the conductive layer 12.

The wiring board 4 can be produced as mentioned above. In addition, by repeating this process, the insulating layer 11 and the conductive layer 12 in the buildup layer 8 can be made more multilayered.

(3) A bump 3 is formed on the upper surface of the pad 14, and the electronic component 2 is flip-chip mounted on the wiring board 4 through the bump 3.

As described above, the mounting structure 1 shown in Fig. 1A can be produced.

This invention is not limited to embodiment mentioned above, A various change, improvement, a combination, etc. are possible in the range which does not deviate from the summary of this invention.

For example, in the above-described embodiment, the configuration in which the buildup layer includes three insulating layers has been described as an example, but the buildup layer may include any number of insulating layers.

In the above-described embodiment, the configuration in which the through hole conductor is filled in the through hole has been described as an example. However, the through hole conductor may be disposed in the through hole and may cover the inner wall of the through hole in a cylindrical shape.

In the above-described embodiment, the configuration in which the via conductor is filled in the via hole has been described as an example. However, the via conductor may be disposed in the via hole, and the inner wall of the via hole may be covered in a cylindrical shape.

In the above-described embodiment, the plurality of via conductors form a stacked structure in which the plurality of via conductors are stacked, but may not be a stacked structure, and may be a spiral structure, for example.

In embodiment mentioned above, although the structure using copper foil was demonstrated at the process of (1) as an example, you may use the metal foil which consists of metal materials, such as iron nickel alloy or iron nickel cobalt alloy, instead of copper foil.

Claims (9)

A core substrate and a build-up layer disposed on the core substrate and mounted on an upper surface thereof,
The core substrate has a base and a plurality of power supply through-hole conductors that penetrate the base in a thickness direction,
The build-up layer includes an insulating layer having a smaller thickness than the base, a plurality of power pads electrically connected to the power terminal of the electronic component and the through-hole conductor for the power supply, and formed on the insulating layer, and the insulating layer in a thickness direction. And a plurality of power supply via conductors for penetrating through and electrically connecting the power supply through hole conductor and the power supply pad,
The wiring board according to claim 1, wherein the number of the power supply through hole conductors in the set of electrically connected pads and the power supply through hole conductors is larger than the number of the power supply pads. The method of claim 1,
The insulating layer has a multilayer structure,
In the set of electrically connected pads for power supply, the via via conductor and the through hole conductor for power supply, the number of the through hole conductors for power is greater than the number of via vias for power passing through the uppermost layer of the layers constituting the insulating layer. A wiring board, characterized in that. The method of claim 1,
The power supply through hole conductor is filled in a power supply through hole that penetrates the base in a thickness direction. The method of claim 1,
The core substrate further has a plurality of ground through hole conductors that penetrate the substrate in the thickness direction,
The build-up layer is electrically connected to the ground terminal of the electronic component and the ground through-hole conductor and formed on the insulating layer, and the ground pad penetrates the insulating layer in a thickness direction and passes through the ground layer. Further having a plurality of ground via conductors for electrically connecting the hole conductor and the ground pad,
The wiring board according to claim 1, wherein the number of ground through-hole conductors in the set of ground pads and the ground-through conductors that are electrically connected is larger than the number of the ground pads. The method of claim 1,
The core substrate further has a plurality of signal through hole conductors that penetrate the substrate in the thickness direction,
The build-up layer is electrically connected to the signal terminal of the electronic component and the signal through hole conductor and is formed on the insulating layer, and a plurality of signal pads formed through the insulating layer, the insulating layer penetrating in the thickness direction, and the signal through hole conductor and the It further has a some signal via conductor which electrically connects a signal pad,
The wiring board according to claim 1, wherein the number of signal through hole conductors in the set of electrically connected signal pads and the signal through hole conductor is equal to the number of the signal pads. The wiring board of Claim 1, and the electronic component mounted on the buildup layer of the said wiring board, and the electronic component in which the terminal for power supply was electrically connected to the power pad, The mounting structure characterized by the above-mentioned. Preparing the gas,
Forming a core substrate by forming a plurality of power supply through hole conductors having penetrated the substrate in the thickness direction by using sand blasting, and forming a plurality of power supply through hole conductors in the plurality of power supply through holes;
The electronic component is mounted by forming an insulating layer having a smaller thickness than the base on the core substrate, and forming a plurality of power pads electrically connected to the power terminal of the electronic component and the through hole conductor for the power component on the insulating layer. Forming a buildup layer to be formed on the core substrate;
The number of said power supply through-hole conductors in said one set of said power supply pads and said power supply through-hole conductor which are electrically connected is larger than the number of said power supply pads. The method of claim 7, wherein
The insulating layer has a multilayer structure, and in the step of forming the build-up layer on the core substrate, a plurality of power supply via holes penetrating the insulating layer in a thickness direction using laser processing are formed, and the plurality of power sources After the plurality of power supply via conductors are formed in the via holes, the plurality of power supply pads electrically connected to the plurality of power supply through hole conductors are formed through the plurality of power supply via conductors,
In the set of electrically connected pads for power supply, the via via conductor and the through hole conductor for power supply, the number of the through hole conductors for power is greater than the number of via vias for power passing through the uppermost layer of the layers constituting the insulating layer. The manufacturing method of the wiring board characterized by the above-mentioned. A process for mounting an electronic component on a buildup layer by electrically connecting a power supply terminal of an electronic component to a power supply pad of a wiring board manufactured by the method for manufacturing a wiring board according to claim 7, wherein the mounting structure is provided. Manufacturing method.

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