JP2004022732A - Circuit board and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit board, capable of realizing stable operations of a semiconductor device or the like at a high frequency region at a low cost, and to provide a manufacturing method thereof. <P>SOLUTION: The circuit board includes a support board 10; a plurality of insulation layers 12a to 12f, 26a to 26f stacked on the support board; and a capacitive component 14 embedded in one insulation layer 12b, being any one of a plurality of the insulation layers, and the height of the upper face of which is nearly equal to the height of the upper face of the insulation layer above. Since the capacitive component is embedded in any one of a plurality of the insulation layers stacked on the support board, the semiconductor device or the like and the capacitive component can be connected at a very short distance, without the need for much wiring around. Thus, power supply voltage variation can be suppressed effectively, and high-frequency noises from a power supply can effectively be eliminated. Thus, a circuit board can be provided contributing to a stable operation of the semiconductor device or the like at a high-frequency region. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a circuit board and a method for manufacturing the same, and more particularly, to a circuit board capable of realizing stable operation in a high-frequency region of a semiconductor device or the like and a method for manufacturing the same.
[0002]
[Prior art]
2. Description of the Related Art Recently, high-speed operation and low power consumption have been achieved in digital LSIs (Large Scale Integrated circuits) such as microprocessors.
[0003]
In order to operate the LSI stably in the high frequency region of the GHz band and at a low voltage, the power supply voltage fluctuation caused by the sudden fluctuation of the load impedance of the LSI is suppressed and the high frequency noise of the power supply is removed. It is extremely important to do so.
[0004]
Conventionally, a decoupling capacitor has been mounted in the vicinity of an LSI or the like mounted on a circuit wiring board, thereby suppressing power supply voltage fluctuation and removing high-frequency noise. The decoupling capacitor is configured using a substrate separate from the circuit wiring substrate, and is appropriately mounted on the circuit wiring substrate.
[0005]
However, when a decoupling capacitor is mounted near an LSI mounted on a circuit wiring board, the LSI and the decoupling capacitor are electrically connected via wiring formed on the circuit wiring board. There is a large inductance due to wiring routing. If a large inductance exists between the LSI and the decoupling capacitor, power supply voltage fluctuation cannot be sufficiently suppressed, and high-frequency noise cannot be sufficiently removed. In order to sufficiently suppress power supply voltage fluctuation and sufficiently remove high-frequency noise, an equivalent series resistance (ESR, equivalent series resistance) and an equivalent series inductance (ESL, equivalent series inductance) between the LSI and the decoupling capacitor are required. Needs to be reduced.
[0006]
Therefore, Japanese Patent Application Laid-Open Nos. 4-2191191 and 7-176453 propose a technique of inserting an interposer type decoupling capacitor between a circuit wiring board and an LSI. If an interposer type decoupling capacitor is inserted between the circuit wiring board and the LSI, the wiring between the LSI and the decoupling capacitor can be shortened, thereby suppressing power supply voltage fluctuation and removing high frequency noise. Can be planned.
[0007]
[Problems to be solved by the invention]
However, in order to manufacture an interposer type decoupling capacitor, it is necessary to form a through-hole in the support substrate and bury a via in the through-hole. In addition, an insulating film must be formed in the through-hole in order to ensure insulation between the via and the support substrate. As described above, the interposer type decoupling capacitor is expensive because the manufacturing process is complicated and the manufacturing requires a long time. In order to effectively suppress power supply voltage fluctuations and remove high-frequency noise, it is desirable to use a high dielectric film or a ferroelectric film as a dielectric film of a capacitor. When a body film is used, a high-temperature heat treatment is required to improve the film quality. For this reason, in the interposer type decoupling capacitor, a material that can withstand high-temperature heat treatment must be used as a material of the supporting substrate. For this reason, an inexpensive organic resin substrate cannot be used. In addition, the above-described proposed technique requires an interposer-type decoupling capacitor separately from the circuit wiring board, so that the overall cost is high.
[0008]
An object of the present invention is to provide a circuit board capable of realizing stable operation in a high frequency region of a semiconductor device or the like at low cost, and a method of manufacturing the same.
[0009]
[Means for Solving the Problems]
The object is to provide a support substrate, a plurality of insulating layers stacked on the support substrate, and one of the plurality of insulating layers embedded in one of the insulating layers, and a height of an upper surface of the one insulating layer. And a capacitor component substantially equal to the height of the upper surface of the circuit board.
[0010]
Further, the above object is a method for manufacturing a circuit board in which a plurality of insulating layers are stacked on a supporting substrate, wherein a step of forming an insulating layer on the supporting substrate, and a step of forming an opening in the insulating layer. Embedding a capacitor component in the opening.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
A circuit board according to a first embodiment of the present invention and a method for fabricating the same will be described with reference to FIGS. FIG. 1 is a sectional view of the circuit board according to the present embodiment. FIG. 1A is a cross-sectional view illustrating the entire configuration of the circuit board according to the present embodiment, and FIG. 1B is a cross-sectional view illustrating a capacitor component used in the present embodiment.
[0012]
(Circuit board)
As shown in FIG. 1A, the circuit board according to the present embodiment has a configuration in which a capacitor component 14 is embedded in one of a plurality of insulating layers 12 stacked on a support substrate 10.
[0013]
Here, a build-up substrate in which a large number of insulating layers 12 and wirings 16 are stacked on a support substrate 10 will be described as an example, but the present invention is applicable not only to a build-up substrate but also to any other circuit boards. It is possible to apply.
[0014]
First, prior to describing the circuit board according to the present embodiment, the capacitor component 14 used in the present embodiment will be described with reference to FIG.
[0015]
As shown in FIG. 1B, a lower electrode 102 is formed on a component support substrate 100 made of, for example, Si. The lower electrode 102 is configured by, for example, sequentially stacking a 100-nm-thick TiN film, a 50-nm-thick Ti film, and a 200-nm-thick Pt film.
[0016]
On the lower electrode 102, for example, a BST ((Ba, Sr) TiO ₃ ) Is formed.
[0017]
On the dielectric film 104, an upper electrode 106 made of, for example, Pt having a thickness of 200 nm is formed.
[0018]
The lower electrode 102, the dielectric film 104, and the upper electrode 106 constitute a capacitor element 108.
[0019]
On the component support substrate 100 on which the capacitor element 108 is formed, a protective film 110 made of, for example, polyimide having a thickness of 2 μm is formed.
[0020]
A contact hole 112 reaching the lower electrode 102 and a contact hole 114 reaching the upper electrode 106 are formed in the protective film 110, respectively.
[0021]
Conductive plugs 116a and 116b made of Cu are buried in the contact holes 112 and 114.
[0022]
The overall thickness of the capacitor component 14 is slightly smaller than the thickness of the insulating layer 12b (see FIG. 1A) in which the capacitor component 14 is embedded. The overall thickness of the capacitor component 14 is slightly smaller than the thickness of the insulating layer 12b in which the capacitor component 14 is embedded because the thickness of the wiring 16b (see FIG. 1B) to which the capacitor component 14 is fixed is reduced. This is because the thickness of the adhesive used when bonding the capacitor component 14 to the wiring 16b is taken into consideration. That is, the thickness of the capacitor component 14 is set such that the height of the upper surface of the capacitor component 14 and the height of the upper surface of the insulating layer 12b are substantially equal when the capacitor component 14 is embedded in the insulating layer 12b.
[0023]
Thus, the capacitor component 14 used in the present embodiment is configured.
[0024]
Next, the circuit board according to the present embodiment will be explained with reference to FIG.
[0025]
As shown in FIG. 1A, a via hole 18 is formed in a supporting substrate 10 which is a core substrate. The support substrate 10 is configured by embedding glass fibers (not shown) in, for example, BT resin.
[0026]
A conductive film 20 made of, for example, Cu is formed on the inner surface of the via hole 18. The resin 22 is filled in the via hole 18 in which the conductive film 20 is formed on the inner surface. Lands 24 made of, for example, Cu are respectively formed above and below the via hole 18 in which the resin 22 is embedded.
[0027]
On the support substrate 10, an insulating layer 12a made of, for example, an organic resin is formed. As a material of the insulating layer 12a, for example, an epoxy resin sheet is used.
[0028]
Wirings 16a to 16c made of, for example, Cu are formed on the insulating layer 12a. The wirings 16a to 16c are connected to the lands 24 via contact holes formed in the insulating layer 12a.
[0029]
An insulating layer 12b is formed on the insulating layer 12a on which the wirings 16a to 16c are formed. As the material of the insulating layer 12b, the same material as that of the insulating layer 12a is used.
[0030]
The above-described capacitor component 14 is embedded in the insulating layer 12b. The component supporting substrate 100 of the capacitor component 14 (see FIG. 1B) is bonded to the wiring 16b using a conductive adhesive (not shown). The height of the upper surface of the capacitor component 14 is substantially equal to the height of the upper surface of the insulating layer 12b. The reason why the height of the upper surface of the capacitor component 14 is substantially equal to the height of the upper surface of the insulating layer 12b is to ensure the flatness of the entire circuit board.
[0031]
Wirings 16d to 16f are formed on the insulating layer 12b in which the capacitor components 14 are embedded.
[0032]
The wiring 16e is electrically connected to, for example, the lower electrode 102 (see FIG. 1B) via the conductor plug 116a of the capacitor component 14 (see FIG. 1B).
[0033]
The wiring 16c is electrically connected to, for example, the upper electrode 106 (see FIG. 1B) via the conductor plug 116b of the capacitor component 14 (see FIG. 1B).
[0034]
On the insulating layer 12b on which the wirings 16d to 16f are formed, the insulating layers 12c to 12f and the wiring 16 are further sequentially laminated.
[0035]
The wirings 16, 16a to 16f are appropriately connected to other wirings 16, 16a to 16f and the like via contact holes formed in the insulating layers 12c to 12f. The number of layers of the wirings 16 and 16a to 16f is, for example, five.
[0036]
The insulating layers 26 a to 26 f and the wiring 28 are sequentially stacked on the lower surface side of the support substrate 10. The wiring 28 is appropriately connected to other wirings 26a to 26f through contact holes formed in the insulating layers 26a to 26f. The number of layers of the wiring 28 is, for example, five.
[0037]
Electrodes 30 are formed on the upper surface side of the insulating layer 12f and the lower surface side of the insulating layer 26f, respectively. The electrode 30 is connected to the wirings 16 and 28 via contact holes formed in the insulating layers 12f and 26f, respectively.
[0038]
A solder resist film 32 is formed on each of the upper surface of the insulating layer 12f on which the electrode 30 is formed and the lower surface of the insulating layer 26f.
[0039]
Openings 34 reaching the electrodes 30 are respectively formed in the solder resist film 32.
[0040]
Solder bumps 36 are formed on the electrodes 30 in the openings 34, respectively.
[0041]
Thus, the circuit board 11 according to the present embodiment is configured.
[0042]
A semiconductor element (not shown) such as an LSI (not shown) is mounted on the circuit board 11 thus configured.
[0043]
As described above, according to the present embodiment, since the capacitor component 14 is embedded in any one of the plurality of insulating layers 12a to 12f stacked on the support substrate 10, the LSI and the capacitor can be connected without wiring. Can be connected over a very short distance. Therefore, according to the present embodiment, the equivalent series inductance and the equivalent series resistance between the LSI and the like and the capacitor can be extremely reduced. For this reason, according to the present embodiment, power supply voltage fluctuation can be effectively suppressed, and high frequency noise of the power supply can be effectively removed. Therefore, according to the present embodiment, it is possible to provide a circuit board that can contribute to a stable operation in a high-frequency region of a semiconductor device or the like.
[0044]
In addition, according to the present embodiment, since the capacitor component 14 formed separately from the support substrate 10 is mounted on the support substrate 10, the dielectric film 104 of the capacitor element 108 has a high dielectric constant or a high dielectric film. A dielectric film can be used. That is, since a high-dielectric film or a ferroelectric film requires a high-temperature heat treatment to improve the film quality, the high-dielectric film or the ferroelectric film is formed on an organic resin substrate that cannot withstand the high-temperature heat treatment. However, in the present embodiment, since the capacitor component 14 formed separately from the support substrate 10 is mounted on the support substrate 10, an organic resin or the like that cannot withstand high-temperature heat treatment is used as the material of the support substrate 10. Even in such a case, a high dielectric film or a ferroelectric film can be used as the dielectric film of the capacitor. According to the present embodiment, since a capacitor having a large capacitance can be connected, power supply voltage fluctuation can be effectively suppressed, and high-frequency noise of the power supply can be effectively removed.
[0045]
The support substrate 10 made of an organic resin is inexpensive and can easily form a via hole or the like using a drill or the like. According to this embodiment, since the material of the support substrate 10 can be inexpensive and can be easily processed, the circuit board 11 having the built-in capacitor can be provided at low cost.
[0046]
Further, according to the present embodiment, it is not necessary to provide an interposer type capacitor separately from the circuit board 11, so that the configuration can be simplified and the cost can be reduced as a whole.
[0047]
(Circuit board manufacturing method)
Next, the method for fabricating the circuit board according to the present embodiment will be explained with reference to FIGS.
[0048]
Prior to describing the method of manufacturing the circuit board according to the present embodiment, the method of manufacturing the capacitor component used in the present embodiment will be described with reference to FIGS. 2 and 3 are process cross-sectional views illustrating a method for manufacturing a capacitor component used in the present embodiment.
[0049]
As shown in FIG. 2A, first, a component support substrate 100 made of, for example, 0.3 mm thick Si is prepared.
[0050]
Next, a 100-nm-thick TiN film, a 50-nm-thick Ti film, and a 200-nm-thick Pt film are sequentially stacked on the entire surface by, for example, a sputtering method. The substrate temperature when forming the Pt film is, for example, 550 ° C. Thus, as shown in FIG. 2B, a lower electrode 102 made of a laminated film is formed.
[0051]
Next, as shown in FIG. 2C, a dielectric film 104 made of BST having a thickness of 120 nm is formed on the entire surface by, for example, a sputtering method. The film forming conditions are, for example, as follows. The substrate temperature is, for example, 650 ° C. Ar gas and O during film formation ₂ The flow ratio with the gas is, for example, 30: 4. The degree of vacuum is, for example, 10 mTorr. The RF applied power is, for example, 100 W. When the film is formed under such film forming conditions and is subjected to a heat treatment described later, a dielectric film 104 having a relative dielectric constant of, for example, 500 is obtained. Since Pt used for the lower electrode 102 is a material that is easily self-oriented to (111), a dielectric film 104 having a uniform crystal orientation is formed on the lower electrode 102.
[0052]
Next, as shown in FIG. 2D, an opening 118 is formed in the dielectric film 104 by using a photolithography technique.
[0053]
Next, as shown in FIG. 2E, an upper electrode 106 made of, for example, a 200-nm-thick Pt film is formed on the entire surface by, for example, a sputtering method. The substrate temperature when forming the upper electrode 106 is, eg, 300 ° C.
[0054]
Next, as shown in FIG. 2F, the upper electrode 106, the dielectric film 104, and the lower electrode 102 are patterned using a photolithography technique. In patterning, for example, argon ion milling is used. The incident angle of the argon ions is, for example, 20 degrees with respect to the component supporting substrate 100.
[0055]
Next, for example, at 450 ° C. ₂ Heat treatment is performed in an atmosphere for 15 minutes. Thereby, the film quality of the dielectric film 104 is improved. Thus, a capacitor 108 including the lower electrode 102, the dielectric film 104, and the upper electrode 106 is formed.
[0056]
Next, as shown in FIG. 3A, a protective film 110 of, eg, a 2 μm-thick polyimide film is formed on the entire surface by, eg, spin coating.
[0057]
Next, a contact hole 112 reaching the lower electrode 102 and a contact hole 114 reaching the upper electrode 106 are formed in the protective film 110 by photolithography.
[0058]
Next, a seed layer (not shown) made of Cu with a thickness of 50 nm is formed on the entire surface by, for example, a sputtering method.
[0059]
Next, a photoresist film 120 is formed on the protective film 110. Thereafter, as shown in FIG. 3B, the photoresist film 120 is patterned by a photolithography technique.
[0060]
Next, as shown in FIG. 3C, conductive plugs 116a and 116b made of Cu are buried in the contact holes 112 and 114 by, for example, electrolytic plating.
[0061]
Next, as shown in FIG. 3D, the photoresist film 120 is removed. Thereafter, the seed layer (not shown) is removed by etching.
[0062]
Next, the back side of the component supporting substrate 100 is polished to make the component supporting substrate 100 thinner.
[0063]
Thus, the capacitor component 14 used in the present embodiment is manufactured.
[0064]
Next, the method for fabricating the circuit board according to the present embodiment will be explained with reference to FIGS. 4 to 9 are process sectional views showing the method for manufacturing the circuit board according to the present embodiment.
[0065]
First, as shown in FIG. 4A, a support substrate 10 is prepared by forming a copper foil (not shown) on both sides of a core substrate made of, for example, a BT resin having a thickness of 0.6 mm.
[0066]
Next, a via hole 18 is formed in the support substrate 10. The via hole 18 can be formed using, for example, a drill. Further, a wiring (not shown) made of copper foil is formed by, for example, a subtractive method.
[0067]
Next, a 20 μm-thick conductive film 20 made of Cu is formed on the inner surface of the via hole 18 by, for example, electrolytic plating.
[0068]
Next, the resin 22 is filled in the via hole 18 in which the conductive film 20 is formed on the inner surface.
[0069]
Next, lands 24 made of Cu having a film thickness of 20 μm are formed above and below the via holes 18 by, for example, electrolytic plating.
[0070]
Next, as shown in FIG. 4B, an epoxy resin sheet having a thickness of, for example, 50 μm is attached to the upper and lower surfaces of the support substrate 10 by, for example, a laminating method. Thus, the insulating layers 12a and 12b made of the epoxy resin sheet are formed.
[0071]
Next, as shown in FIG. 4C, a contact hole 38 reaching the land 14 is formed in the insulating layers 12a and 12b using, for example, a UV-YAG laser.
[0072]
Next, as shown in FIG. 4D, a seed layer 40 made of Cu having a thickness of 0.5 μm is formed on the entire surface by, for example, electroless plating.
[0073]
Next, as shown in FIG. 5A, a dry film resist film 42 is attached to the upper surface side and the lower surface side of the support substrate 10 by, for example, a lamination method. Thereafter, the dry film resist film 42 is patterned using a photolithography technique. As a result, an opening 44 for forming the wirings 16 a to 16 c and 28 is formed in the dry film resist film 42.
[0074]
Next, as shown in FIG. 5B, wirings 16a to 16c and 28 made of, for example, Cu are formed in the opening 44 by electrolytic plating.
[0075]
Next, as shown in FIG. 5C, the dry film resist film 42 is removed.
[0076]
Next, as shown in FIG. 6A, the seed layer 40 is removed by etching. 6A to 9B, illustration of the seed layer 40 is omitted.
[0077]
Next, as shown in FIG. 6B, an epoxy resin sheet having a thickness of, for example, 30 μm is attached to the upper surface of the insulating layer 12a and the lower surface of the insulating layer 26a by, for example, a lamination method. Thus, the insulating layers 12b and 26b made of the epoxy resin sheet are formed.
[0078]
Next, as shown in FIG. 6C, a contact hole 46 reaching the wirings 16a and 16c is formed in the insulating layer 12b by using, for example, a UV-YAG laser, and an opening reaching the wiring 16b is formed in the insulating layer 12b. 48 are formed. The opening 48 is for embedding the capacitor component 14. Similarly, a contact hole 46 reaching the wiring 28 is formed in the insulating layer 26b. Thereafter, a desmear process is performed.
[0079]
Next, as shown in FIG. 7A, the capacitor component 14 is embedded in the opening 48. Specifically, the lower surface side of the component support substrate 100 of the capacitor component 14 is bonded to the wiring 16c using an adhesive. As the adhesive, for example, a copper paste can be used. In this embodiment, since the capacitor component 14 is fixed using the adhesive, the capacitor component 14 can be easily fixed without performing soldering.
[0080]
Next, as shown in FIG. 7B, wirings 16d to 16f and 28 are formed. The wirings 16d to 16f and 28 can be formed in the same manner as described above. The wiring 16d is electrically connected to, for example, the upper electrode 106 via the conductor plug 116b of the capacitor component 14, for example. The wiring 16e is electrically connected to the lower electrode 102 via the conductor plug 116a of the capacitor component 14, for example.
[0081]
Thereafter, the wirings 16 and 28 and the insulating layers 12c to 12f and 26c to 26f are sequentially laminated in the same manner as described above (see FIGS. 7B and 8A).
[0082]
Next, as shown in FIG. 8A, electrodes 30 connected to the wirings 16 and 28 via contact holes are formed on the upper surface of the insulating layer 12f and the lower surface of the insulating layer 26f.
[0083]
Next, as shown in FIG. 8B, a solder resist film 32 is formed on the upper surface of the insulating layer 12f and the lower surface of the insulating layer 26f.
[0084]
Next, as shown in FIG. 9A, an opening 34 reaching the electrode 30 is formed in the solder resist film 32.
[0085]
Next, as shown in FIG. 9B, solder bumps 36 are formed on the upper surface and the lower surface of the electrode 30, respectively.
[0086]
Thus, the circuit board 11 according to the present embodiment is manufactured.
[0087]
[Second embodiment]
A circuit board and a method of manufacturing the same according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 10 is a sectional view of the circuit board according to the present embodiment. FIG. 10A is a cross-sectional view illustrating the overall configuration of the circuit board according to the present embodiment. FIG. 10B is a cross-sectional view illustrating a capacitor component used in the present embodiment. The same components as those of the circuit board and the method of manufacturing the same according to the first embodiment shown in FIGS. 1 to 9 are denoted by the same reference numerals, and description thereof will be omitted or simplified.
[0088]
(Circuit board)
The circuit board according to the present embodiment uses a conductive support substrate as a support substrate for the capacitor component, and the lower electrode and the wiring are electrically connected via the conductive support substrate. Has the main features.
[0089]
First, prior to describing the circuit board according to the present embodiment, the capacitor component 14a used in the present embodiment will be described with reference to FIG.
[0090]
As shown in FIG. 10B, in the present embodiment, a component supporting substrate 100a having conductivity is used for the capacitor component 14a. As the component supporting substrate 100a having conductivity, for example, a supporting substrate made of Si into which impurities are introduced can be used. The specific resistance of the component support substrate 100a is, for example, 10 Ω · cm or less.
[0091]
On the component supporting substrate 100a, a capacitor element 108 including a lower electrode 102, a dielectric film 104, and an upper electrode 106 is formed.
[0092]
A protective film 110 is formed on the component support substrate 100a on which the capacitor element 108 is formed. In the protective film 110, a contact hole 114a reaching the upper electrode 106 is formed. A conductor plug 116c is embedded in the contact hole 114a.
[0093]
In the capacitor component 14a used in the present embodiment, since the component supporting substrate 100a having conductivity is used, the lower electrode 102 and the wiring 16b (see FIG. 10A) are connected via the component supporting substrate 100a. Can be electrically connected.
[0094]
Thus, the capacitor component 14a used in the present embodiment is configured.
[0095]
Next, the circuit board according to the present embodiment will be explained with reference to FIG.
[0096]
As shown in FIG. 10, a capacitor component 14b is embedded in the insulating layer 12b. The component supporting substrate 100a of the capacitor component 14b is bonded to the wiring 16b with a conductive adhesive (not shown). Thus, the lower electrode 102 of the capacitor component 14a is electrically connected to the wiring 16b via the component support substrate 100a. For example, a copper paste can be used as the conductive adhesive.
[0097]
The wiring 16e is formed on the insulating layer 12b in which the capacitor 14a is embedded. The wiring 16e is electrically connected to the upper electrode 106 via the conductor plug 116c of the capacitor component 14a.
[0098]
Thus, the circuit board 11a according to the present embodiment is configured.
[0099]
As described above, the component supporting substrate 100a having conductivity may be used for the capacitor component 14a.
[0100]
As described above, according to the present embodiment, since the component supporting substrate 100a having conductivity is used for the capacitor component 14a, the lower electrode 102 is electrically connected to the wiring 16b via the component supporting substrate 100a. be able to. For this reason, according to the present embodiment, the degree of freedom in design can be improved.
[0101]
(Circuit board manufacturing method)
Next, the method for fabricating the circuit board according to the present embodiment will be explained with reference to FIGS.
[0102]
Prior to describing the method of manufacturing the circuit board according to the present embodiment, the method of manufacturing the capacitor used in the present embodiment will be described with reference to FIGS. 11 and 12 are process cross-sectional views illustrating a method for manufacturing a capacitor component used in the present embodiment.
[0103]
As shown in FIG. 11, first, a component supporting substrate 100a having conductivity is prepared. As the component supporting substrate 100a having conductivity, for example, a supporting substrate made of Si into which impurities are introduced can be used. The thickness of the component support substrate 100a is, for example, 0.3 mm, and the specific resistance of the component support substrate 100a is, for example, 10 Ω · cm or less.
[0104]
The subsequent method of manufacturing the capacitor shown in FIGS. 11B and 11C is similar to the method of manufacturing the capacitor described above with reference to FIGS. I do.
[0105]
Next, as shown in FIG. 11D, an upper electrode 106 made of a Pt film having a thickness of, for example, 200 nm is formed on the entire surface by, for example, a sputtering method. Thereafter, heat treatment for improving the film quality of the dielectric film 104 is performed in the same manner as described above. Thereafter, the upper electrode 106, the dielectric film 104, and the lower electrode 102 are patterned in the same manner as described above. Thus, a capacitor element 108 including the lower electrode 102, the dielectric film 104, and the upper electrode 106 is formed.
[0106]
Next, as shown in FIG. 11E, a protective film 110 made of, for example, a 2 μm-thick polyimide film is formed on the entire surface by, eg, spin coating.
[0107]
Next, a contact hole 114a reaching the upper electrode 106 is formed in the protective film 110 by using a photolithography technique.
[0108]
Next, a seed layer (not shown) made of Cu, for example, having a thickness of 50 nm is formed on the entire surface in the same manner as described above.
[0109]
Next, as shown in FIG. 11F, a photoresist film 120a is formed on the protective film 110. Thereafter, the photoresist film 120a is patterned by photolithography.
[0110]
Next, as shown in FIG. 12A, a conductor plug 116c made of Cu is embedded in the contact hole 114a by, for example, an electrolytic plating method.
[0111]
Next, as shown in FIG. 12B, the photoresist film 120a is removed. Thereafter, the seed layer (not shown) is removed by etching.
[0112]
Next, in the same manner as described above, the back side of the component support substrate 100a is polished to make the component support substrate 100a thin.
[0113]
Thus, the capacitor component 14a used in the present embodiment is manufactured.
[0114]
Next, the method for fabricating the circuit board according to the present embodiment will be explained with reference to FIGS. 13 to 15 are process sectional views showing the method for manufacturing the circuit board according to the present embodiment.
[0115]
First, up to the step of forming the contact hole 46 and the opening 48 reaching the wirings 16a, 16c, 28 in the insulating layers 12b, 26b, the method of manufacturing the circuit board shown in FIGS. The description is omitted because it is similar.
[0116]
Next, as shown in FIG. 13A, the capacitor component 14a is embedded in the opening 48. Specifically, the lower surface side of the component support substrate 100a of the capacitor component 14a is bonded to the wiring 16b using a conductive adhesive (not shown). For example, a copper paste can be used as the conductive adhesive. As a result, the lower electrode 102 of the capacitor component 14a is electrically connected to the wiring 16b via the component support substrate 100a.
[0117]
Next, as shown in FIG. 13B, wirings 16d to 16f are formed on the insulating layer 12b. Wiring 16e is electrically connected to upper electrode 106 via conductor plug 116c of capacitor component 14a.
[0118]
The subsequent method of manufacturing the circuit board shown in FIGS. 13C to 15B is the same as the method of manufacturing the circuit board shown in FIGS. 7C to 9B, and thus the description is omitted. .
[0119]
Thus, the circuit board 11a according to the present embodiment is manufactured.
[0120]
[Modified embodiment]
The present invention is not limited to the above embodiment, and various modifications are possible.
[0121]
For example, in the above embodiment, BST was used as the material of the dielectric film 104, but the material of the dielectric film 104 is not limited to BST, and any other high-dielectric film or ferroelectric film may be used. You may. For example, a high-dielectric film or a ferroelectric film made of a composite oxide containing at least one of Sr, Ba, Pb, Zr, Bi, Ta, Ti, Mg, and Nb can be used as appropriate. Specifically, for example, (Ba, Sr) TiO ₃ , Pb (Zr, Ti) O ₃ , SrBi ₂ Ta ₂ O ₉ , Pb (Mg, Nb) O ₃ , Ta ₂ O ₅ Etc. can be used as appropriate. The dielectric film 104 is not limited to a high dielectric film or a ferroelectric film, and any other dielectric film may be used as appropriate. However, the use of a high dielectric film or a ferroelectric film is advantageous because a large-capacity and small-sized capacitor component can be formed.
[0122]
In the above embodiment, the copper paste is used as the conductive adhesive. However, the conductive adhesive is not limited to the copper paste, and any other conductive adhesive can be used as appropriate. For example, a conductive adhesive containing Ag, Cu, Au, Pd, or the like may be used.
[0123]
Further, in the above embodiment, Pt or the like is used for the lower electrode 102 and the upper electrode 106, but the material of the lower electrode 102 and the upper electrode 106 is not limited to Pt, and any other electrode material may be appropriately used. Can be. For example, Au, Cu, Pd, Ru, Ru oxide, Ir, Ir oxide, Cr, or the like may be used as a material of the lower electrode 102 and the upper electrode 106.
[0124]
Further, in the above embodiment, the capacitor component is embedded in only one location, but the capacitor component may be embedded in a plurality of locations as appropriate. That is, it is sufficient to appropriately embed a capacitor component in a place where suppression of power supply voltage fluctuation, removal of high-frequency noise, and the like are required.
[0125]
Further, in the second embodiment, the lower electrode 102, the dielectric film 104, and the upper electrode 106 are sequentially formed on the conductive component supporting substrate 100a, but the lower electrode is formed on the conductive component supporting substrate 100a. Instead, the dielectric film 102 and the upper electrode 104 may be formed sequentially. That is, the conductive support substrate 102 may be configured to also serve as the lower electrode.
[0126]
(Supplementary Note 1)
A plurality of insulating layers stacked on the support substrate,
A capacitor component embedded in one of the plurality of insulating layers, the height of the upper surface being substantially equal to the height of the upper surface of the one insulating layer;
A circuit board comprising:
[0127]
(Supplementary Note 2) In the circuit board according to Supplementary Note 1,
The support substrate is made of an organic resin,
The insulating layer is made of an organic resin
A circuit board, characterized in that:
[0128]
(Supplementary Note 3) In the circuit board according to Supplementary Note 1 or 2,
A first wiring and a second wiring formed on the one insulating layer;
The capacitor component includes a component support substrate, a lower electrode formed on the component support substrate, a dielectric film formed on the lower electrode, and an upper electrode formed on the dielectric film. Has,
The first wiring is electrically connected to the lower electrode,
The second wiring is electrically connected to the upper electrode
A circuit board, characterized in that:
[0129]
(Supplementary Note 4) In the circuit board according to Supplementary Note 1 or 2,
A first wiring formed under the one insulating layer;
And a second wiring formed on the one insulating layer,
The capacitor component includes a component support substrate having conductivity, a lower electrode formed on the component support substrate, a dielectric film formed on the lower electrode, and formed on the dielectric film. And an upper electrode,
The first wiring is electrically connected to the lower electrode via the component support substrate,
The second wiring is electrically connected to the upper electrode
A circuit board, characterized in that:
[0130]
(Supplementary Note 5) In the circuit board according to Supplementary Note 4,
The component support substrate also serves as the lower electrode of the capacitor element.
A circuit board, characterized in that:
[0131]
(Supplementary note 6) In the circuit board according to Supplementary note 4 or 5,
The specific resistance of the component supporting substrate is 10 Ω · cm or less.
A circuit board, characterized in that:
[0132]
(Supplementary Note 7) In the circuit board according to any one of Supplementary Notes 4 to 6,
The component support substrate is fixed to the first wiring using a conductive adhesive.
A circuit board, characterized in that:
[0133]
(Supplementary Note 8) In the circuit board according to Supplementary Note 7,
The conductive adhesive contains Ag, Cu, Au or Pd
A circuit board, characterized in that:
[0134]
(Supplementary Note 9) In the circuit board according to any one of Supplementary Notes 3 to 8,
The dielectric film is made of a composite oxide containing at least one of Sr, Ba, Pb, Zr, Bi, Ta, Ti, Mg, and Nb.
A circuit board, characterized in that:
[0135]
(Supplementary Note 10) In the circuit board according to any one of Supplementary Notes 3 to 9,
At least one of the lower electrode and the upper electrode is made of Pt, Au, Cu, Pd, Ru, Ru oxide, Ir, Ir oxide, or Cr.
A circuit board, characterized in that:
[0136]
(Supplementary Note 11) A method of manufacturing a circuit board in which a plurality of insulating layers are stacked on a support substrate,
Forming an insulating layer on the supporting substrate;
Forming an opening in the insulating layer;
Embedding a capacitor component in the opening;
A method for manufacturing a circuit board, comprising:
[0137]
(Supplementary Note 12) In the method for manufacturing a circuit board according to supplementary note 11,
Further comprising a step of forming a wiring before the step of forming the insulating layer,
The capacitor component includes a component support substrate having conductivity, a lower electrode formed on the component support substrate, a dielectric film formed on the lower electrode, and formed on the dielectric film. And an upper electrode,
In the step of embedding the capacitor, the lower electrode and the first wiring are connected via the component supporting substrate by bonding the component supporting substrate to the first wiring using a conductive adhesive. Connect electrically
A method for manufacturing a circuit board, comprising:
[0138]
【The invention's effect】
As described above, according to the present invention, since the capacitor component is embedded in any of the plurality of insulating layers stacked on the support substrate, the LSI and the capacitor can be connected over a very short distance without routing the wiring. Can be connected. Therefore, according to the present invention, the equivalent series inductance and the equivalent series resistance between the LSI and the like and the capacitor can be extremely reduced. Therefore, according to the present invention, power supply voltage fluctuation can be effectively suppressed, and high-frequency noise of the power supply can be effectively removed. Therefore, according to the present invention, it is possible to provide a circuit board that can contribute to a stable operation in a high-frequency region of a semiconductor device or the like.
[0139]
Further, according to the present invention, in order to mount a capacitor component formed separately from the support substrate on the support substrate, even when an organic resin or the like that cannot withstand high-temperature heat treatment is used as the material of the support substrate, A high dielectric film or a ferroelectric film can be used as the dielectric film of the capacitor. According to the present invention, since a capacitor having a large capacitance can be connected, power supply voltage fluctuation can be effectively suppressed, and high-frequency noise of the power supply can be effectively removed.
[0140]
Further, according to the present invention, since a material such as an organic resin which can be processed at low cost and can be easily processed can be used as the material of the support substrate, a circuit board having a built-in capacitor can be provided at low cost.
[0141]
Further, according to the present invention, since it is not necessary to provide an interposer type capacitor separately from the circuit board, the configuration can be simplified and the cost can be reduced as a whole.
[0142]
Further, according to the present invention, since the component supporting substrate having conductivity is used for the capacitor component, the lower electrode can be electrically connected to the wiring via the component supporting substrate. For this reason, according to the present invention, the degree of freedom in design can be improved.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a circuit board according to a first embodiment of the present invention.
FIG. 2 is a process cross-sectional view (part 1) illustrating the method for manufacturing the capacitor component used in the first embodiment of the present invention.
FIG. 3 is a process sectional view (part 2) illustrating the method for manufacturing the capacitor component used in the first embodiment of the present invention.
FIG. 4 is a process cross-sectional view (part 1) illustrating the method for manufacturing a circuit board according to the first embodiment of the present invention;
FIG. 5 is a process sectional view (part 2) illustrating the method for manufacturing the circuit board according to the first embodiment of the present invention.
FIG. 6 is a process sectional view (part 3) illustrating the method for manufacturing the circuit board according to the first embodiment of the present invention.
FIG. 7 is a process sectional view (part 4) illustrating the method for manufacturing the circuit board according to the first embodiment of the present invention.
FIG. 8 is a process sectional view (part 5) illustrating the method for manufacturing the circuit board according to the first embodiment of the present invention.
FIG. 9 is a process sectional view (part 6) illustrating the method for manufacturing the circuit board according to the first embodiment of the present invention.
FIG. 10 is a sectional view showing a circuit board according to a second embodiment of the present invention.
FIG. 11 is a process cross-sectional view (part 1) illustrating the method for manufacturing the capacitor component used in the second embodiment of the present invention.
FIG. 12 is a process sectional view (part 2) illustrating the method for manufacturing the capacitor component used in the second embodiment of the present invention.
FIG. 13 is a process sectional view (part 1) illustrating the method for manufacturing the circuit board according to the second embodiment of the present invention.
FIG. 14 is a process sectional view (part 2) illustrating the method for manufacturing the circuit board according to the second embodiment of the present invention.
FIG. 15 is a process sectional view (part 3) illustrating the method for manufacturing the circuit board according to the second embodiment of the present invention.
[Explanation of symbols]
10 ... Support substrate
11, 11a ... circuit board
12a to 12f: insulating layer
14, 14a ... capacitor parts
16, 16a to 16f ... wiring
18 ... Beer hole
20 ... conductive film
22 ... resin
24 ... Land
26a to 26f ... insulating layer
28 ... Wiring
30 ... electrode
32 ... Solder resist film
34 ... Opening
36 ... Solder bump
38 ... Contact hole
40 ... Seed layer
42 ... Dry film resist film
44 ... Opening
46… Contact hole
48 ... Opening
100, 100a ... Support substrate for components
102 ... Lower electrode
104: Dielectric film
106: Upper electrode
108 ... Capacitor element
110 ... Protective film
112 ... Contact hole
114, 114a ... contact hole
116a, 116b, 116c ... conductor plug
118 ... opening
120, 120a ... photoresist film

Claims (9)

A support substrate;
A plurality of insulating layers stacked on the support substrate,
A circuit board, comprising: a capacitor component embedded in one of the plurality of insulating layers and having a height of an upper surface substantially equal to a height of an upper surface of the one insulating layer. The circuit board according to claim 1,
The support substrate is made of an organic resin,
The circuit board, wherein the insulating layer is made of an organic resin. The circuit board according to claim 1 or 2,
A first wiring and a second wiring formed on the one insulating layer;
The capacitor component includes a component support substrate, a lower electrode formed on the component support substrate, a dielectric film formed on the lower electrode, and an upper electrode formed on the dielectric film. Has,
The first wiring is electrically connected to the lower electrode,
The said 2nd wiring is electrically connected to the said upper electrode, The circuit board characterized by the above-mentioned. The circuit board according to claim 1 or 2,
A first wiring formed under the one insulating layer;
And a second wiring formed on the one insulating layer,
The capacitor component includes a component support substrate having conductivity, a lower electrode formed on the component support substrate, a dielectric film formed on the lower electrode, and formed on the dielectric film. And an upper electrode,
The first wiring is electrically connected to the lower electrode via the component support substrate,
The said 2nd wiring is electrically connected to the said upper electrode, The circuit board characterized by the above-mentioned. The circuit board according to claim 4,
The circuit board, wherein the component support substrate also serves as the lower electrode of the capacitor element. The circuit board according to claim 4 or 5,
A circuit board, wherein the specific resistance of the component support board is 10 Ω · cm or less. The circuit board according to any one of claims 4 to 6,
The circuit board, wherein the component support substrate is fixed to the first wiring using a conductive adhesive. A method for manufacturing a circuit board having a plurality of insulating layers laminated on a support substrate,
Forming an insulating layer on the supporting substrate;
Forming an opening in the insulating layer;
Embedding a capacitor component in the opening. The method for manufacturing a circuit board according to claim 8,
Further comprising a step of forming a wiring before the step of forming the insulating layer,
The capacitor component includes a component support substrate having conductivity, a lower electrode formed on the component support substrate, a dielectric film formed on the lower electrode, and formed on the dielectric film. And an upper electrode,
In the step of embedding the capacitor, the lower electrode and the first wiring are connected via the component supporting substrate by bonding the component supporting substrate to the first wiring using a conductive adhesive. A method for manufacturing a circuit board, comprising electrically connecting.

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