JP2009289802A - Module having electronic part built-in and production method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a module with a built-in electronic part for forming a via hole conductor in a narrow pitch even when the module includes a built-in electronic part having a relative large height. <P>SOLUTION: This module includes: an insulating layer 120 in which electronic parts 131, 132 and an intermediary substrate 140 are embedded and a via hole conductor 182 electrically connected to the intermediary substrate 140 is formed; a wiring layer 161 formed in one side from the insulating layer 120 and electrically-connected to at least electronic parts 131, 132; and a wiring layer 163 formed in another side from the insulating layer 120, wherein the electronic part 131 and the wiring layer 163 are electrically connected via the intermediary substrate 140 and the via hole conductor 182. Since the wiring layers 161, 163 are connected via the intermediary substrate 140, the depth of the via hole conductor 182 is reduced. Thus, the opening diameter of the via hole is reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic component built-in module and a manufacturing method thereof, and more particularly to a high-functional electronic component built-in module mounted on a motherboard and a manufacturing method thereof.

  For electronic devices such as personal computers, digital cameras, and mobile phones, a motherboard on which electronic components such as semiconductor ICs and capacitors are mounted is used. In addition to directly mounting these electronic components, a motherboard on which electronic components or the like are mounted in advance may be mounted on the motherboard.

Such a module is generally composed of a module substrate having a multilayer wiring structure and an electronic component mounted on the surface of the module substrate. However, in recent years, due to the demand for higher functionality, a technique has been proposed in which an electronic component is not only mounted on the surface of the module substrate but also embedded in the module substrate (see Patent Document 1). According to this, since the surface of the module substrate can be used more effectively, a highly functional module can be configured.
JP 2003-197849 A

  However, among electronic components embedded in the module substrate, there are relatively high components. In such a case, since the thickness of the insulating layer in which the electronic component is embedded is increased to some extent, it is necessary to form a deep via hole penetrating the insulating layer in order to establish conduction above and below the insulating layer.

  As a method for forming a via hole, a method using a drill or a method using laser irradiation is known. However, the method using a drill has a problem that it is difficult to form a large number of via holes at a narrow pitch. On the other hand, according to the laser irradiation method, it is possible to form via holes with a narrower pitch than the method using a drill, but the via holes formed by laser irradiation have a tapered cross section. For this reason, when the depth of the via hole increases, the opening diameter on the laser irradiation side inevitably increases, and there is a problem that the formation pitch of the via hole is limited.

  As described above, when an electronic component having a relatively high height is built in the module substrate, it is difficult to reduce the formation pitch of the via-hole conductors, which hinders downsizing of the module.

  Therefore, an object of the present invention is to provide an electronic component built-in module capable of forming via-hole conductors at a narrow pitch even when a relatively high electronic component is built in and a method for manufacturing the same. is there.

  An electronic component built-in module according to the present invention includes an insulating layer in which an electronic component and a relay substrate are embedded, and a first wiring layer formed on one side as viewed from the insulating layer and electrically connected to the electronic component and the relay substrate. And a second wiring layer formed on the other side when viewed from the insulating layer, and a via-hole conductor that electrically connects the second wiring layer and the relay substrate, the first wiring layer and the second wiring layer The wiring layer is electrically connected through a relay substrate and a via-hole conductor.

  According to the present invention, since the wiring layers formed above and below the insulating layer are connected via the relay substrate, the depth of the via-hole conductor can be reduced. Thereby, even when the via hole is formed by laser irradiation, the opening diameter on the laser irradiation side can be kept small, and the formation pitch of the via hole conductor can be reduced.

  The electronic component built-in module according to the present invention further includes a first core substrate disposed on one side as viewed from the insulating layer, and the electronic component and the relay substrate are preferably mounted on the first core substrate. According to this, after the electronic component and the relay substrate are mounted on the core substrate having high strength, these can be embedded in the insulating layer, and thus the manufacture is facilitated. In addition, since the mechanical strength of the entire module is increased by the core substrate, it is possible to improve reliability.

  The electronic component built-in module according to the present invention preferably further includes a second core substrate disposed on the other side as viewed from the insulating layer. This further increases the mechanical strength of the entire module. In addition, since the core substrate is located on both sides of the insulating layer, module warpage due to temperature change is less likely to occur. Further, since the second wiring layer can be formed on the second core substrate, the wiring layer is directly formed on the surface of the insulating layer even when the adhesion between the wiring layer and the insulating layer is low. There is no need.

  In the present invention, it is preferable that a semiconductor IC is embedded in the relay substrate. According to this, it becomes possible to make the module more functional. Further, the semiconductor IC can be mounted not only inside the relay substrate but also on the surface of the module.

  In addition, the method of manufacturing the electronic component built-in module according to the present invention includes a step of mounting the electronic component and the relay substrate on the first core substrate, and forming an insulating layer on the first core substrate, A step of embedding the relay substrate in the insulating layer; and a step of forming a via-hole conductor electrically connected to the relay substrate in the insulating layer from the side opposite to the first core substrate.

  According to the present invention, since the depth of the via hole conductor is sufficiently smaller than the thickness of the insulating layer, the formation pitch of the via hole conductor can be reduced.

  In the present invention, the via hole conductor is preferably formed by forming a via hole in the insulating layer by laser irradiation and then forming a conductor in the via hole. As described above, even when a via hole is formed by laser irradiation, the opening diameter on the laser irradiation side can be kept small, so that the formation pitch of the via hole conductor can be reduced.

  The manufacturing method of the electronic component built-in module according to the present invention preferably further includes a step of forming the second core substrate on the side opposite to the first core substrate when viewed from the insulating layer. According to this, it becomes possible to produce a module with higher mechanical strength.

  As described above, according to the present invention, it is possible to form the via-hole conductors at a narrow pitch even when a relatively high electronic component is built in the module. Thereby, it is possible to realize high functionality while downsizing the module.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic cross-sectional view showing the structure of an electronic component built-in module 100 according to a preferred first embodiment of the present invention.

  As shown in FIG. 1, the electronic component built-in module 100 according to the present embodiment includes a core substrate 110, an insulating layer 120 provided on one surface 110 a side of the core substrate 110, and an electronic component embedded in the insulating layer 120. 131 and 132, the relay substrate 140, and the semiconductor IC 150 provided on the other surface 110b side of the core substrate 110.

  The core substrate 110 is made of a glass cloth, a resin cloth such as a Kevlar or liquid crystal polymer, a non-woven cloth such as an aramid or an aromatic polyester, a core material made of a porous sheet such as a fluororesin, a thermosetting resin or a thermoplastic resin. It has an impregnated structure. For this reason, the core substrate 110 has a relatively high mechanical strength. The thickness of the core substrate 110 is not particularly limited, but is preferably set to 100 μm or less.

  A wiring layer 161 is formed on one surface 110 a of the core substrate 110, and a portion where the wiring layer 161 is not formed is covered with a resist 171. A wiring layer 162 is formed on the other surface 110 b of the core substrate 110. Some of these wiring layers 161 and 162 are electrically connected by a via-hole conductor 181 provided so as to penetrate the core substrate 110.

  As shown in FIG. 1, the electronic components 131 and 132 and the relay substrate 140 are connected to a wiring layer 161 provided on the core substrate 110. The type of electronic component to be embedded is not particularly limited, and may be a passive element such as a chip capacitor, a chip capacitor, or a resistor, or an active element such as a transistor or a diode, or a semiconductor IC. It doesn't matter. Further, the number of embedded electronic components is not particularly limited.

  The relay substrate 140 is a multi-layer substrate with a built-in semiconductor IC 141, and is a separately manufactured circuit component. In other words, the relay board 140 is a submodule that performs a predetermined function by itself. A terminal electrode 142 is provided on one surface 140 a of the relay substrate 140 and is connected to the wiring layer 161. Although not particularly limited, it is preferable to use solder bumps as the terminal electrodes 142. A terminal electrode 143 is provided on the other surface 140 b of the relay substrate 140.

  The internal wiring 144 included in the relay substrate 140 includes one that connects the semiconductor IC 141 and the terminal electrodes 142 and 143, and one that connects the terminal electrode 142 and the terminal electrodes 143. That is, the relay substrate 140 performs a predetermined operation by the built-in semiconductor IC 141 and plays a role as a circuit substrate for short-circuiting the terminal electrode 142 and the terminal electrode 143.

  As described above, the insulating layer 120 is a layer in which the electronic components 131 and 132 and the relay substrate 140 are embedded, and a thermosetting resin or a thermoplastic resin can be used. Specifically, epoxy resin, bismaleimide-triazine resin (BT resin), phenol resin, vinyl benzyl resin, polyphenylene ether (polyphenylene ether oxide) resin (PPE, PPO), cyanate resin, benzoxazine resin, polyimide resin, aromatic A group polyester resin, polyphenylene sulfide resin, polyetherimide resin, polyarylate resin, polyetheretherketone resin, and the like can be selected. Moreover, you may use the material which made the said resin contain the filler.

  The thickness of the insulating layer 120 is set to be thicker than the height of the electronic components 131 and 132 and the relay substrate 140 so that the electronic components 131 and 132 and the relay substrate 140 are completely embedded. Therefore, it is necessary to increase the thickness of the insulating layer 120 as the heights of the electronic components 131 and 132 to be embedded and the relay substrate 140 are higher.

  As shown in FIG. 1, a wiring layer 163 is provided on the surface 120 a of the insulating layer 120, and a part of the wiring layer 163 is connected to the terminal electrode 143 of the relay substrate 140 via the via-hole conductor 182. Thereby, a part of the wiring layer 163 is connected to the semiconductor IC 141 built in the relay substrate 140, and the other part is connected to the wiring layer 161 via the relay substrate 140. As described above, since the electronic components 131 and 132 are connected to the wiring layer 161, the wiring layer 162 and the electronic components 131 and 132 are electrically connected via the via-hole conductor 182, the relay substrate 140, and the wiring layer 161. Will be connected. The surface 120 b of the insulating layer 120 is in contact with the core substrate 110.

  The semiconductor IC 150 is mounted on the core substrate 110 via the conductive paste 151. The pad electrode 152 of the semiconductor IC 150 is connected to the wiring layer 162 via the bonding wire 153. The bonding wire 153 is protected by the sealing resin 154. In the example shown in FIG. 1, the main surface of the semiconductor IC 150 is not covered with the sealing resin 154, but the entire main surface may be covered with the sealing resin 154. That is, when using a semiconductor IC that needs to expose the light receiving surface such as a PDIC (Photo Diode IC), the main surface may be exposed as shown in FIG. In the case of using, the entire surface may be covered with the sealing resin 154.

  The above is the configuration of the electronic component built-in module 100 according to the present embodiment. As described above, the electronic component built-in module 100 according to the present embodiment includes the insulating layer 120 having a relatively large thickness, but no via-hole conductor penetrating the insulating layer 120 is provided, and both sides of the insulating layer 120 are provided. The wiring layer 161 and the wiring layer 163 located at are electrically connected via the relay substrate 140. For this reason, since the depth of the via-hole conductor 182 to be formed in the insulating layer 120 becomes shallow, the formation pitch of the via-hole conductor 182 can be reduced. In particular, if the thickness of the relay substrate 140 is set to be more than half of the thickness of the insulating layer 120, the depth of the via-hole conductor 182 can be sufficiently reduced, so that the via-hole conductor 182 is formed at a narrower pitch. Is possible.

  In addition, in the present embodiment, the function of the module 100 and the connection relationship between the wiring layer 161 and the wiring layer 163 can be changed depending on the circuit configuration of the relay substrate 140. Therefore, by appropriately selecting the relay board 140 having various circuit configurations, it is possible to configure a module having a desired function without changing the design of other parts of the module 100. For example, it is possible to change the function of the module 100 by preparing a plurality of relay boards 140 of different types of built-in semiconductor ICs 141, selecting the necessary relay boards 140 from these, and embedding them in the insulating layer 120. It becomes. Therefore, the design cost of the module 100 can be reduced.

  The electronic component built-in module 100 having the above configuration can be mounted on a motherboard of an electronic device such as a personal computer, a digital camera, or a mobile phone.

  Next, the manufacturing method of the electronic component built-in module 100 according to the present embodiment will be described.

  2 to 6 are process diagrams for explaining the method of manufacturing the electronic component built-in module 100 according to the present embodiment.

  As shown in FIG. 2, the core substrate 110 is prepared first. As described above, the core substrate 110 is a high-strength substrate in which a core material is impregnated with a resin, and wiring layers 161 and 162 are formed on both surfaces thereof. The formation method of the wiring layers 161 and 162 is not particularly limited, and may be formed by etching the conductor foil or may be formed by plating. A part of the wiring layers 161 and 162 is electrically connected by a via-hole conductor 181.

  Next, as shown in FIG. 3, the electronic components 131 and 132 and the relay substrate 140 are mounted on the core substrate 110. The electronic components 131 and 132 are mounted using the solder 133, and the relay substrate 140 is mounted using the solder bumps that constitute the terminal electrodes 142. That is, after supplying solder to the wiring layer 161 provided on the core substrate 110, the electronic components 131 and 132 and the relay substrate 140 are placed at predetermined positions, and batch reflow is performed. Thereby, the electronic components 131 and 132 and the relay substrate 140 are electrically and mechanically connected to the core substrate 110.

  Next, as shown in FIG. 4, after embedding the electronic components 131 and 132 and the relay substrate 140 using a thermosetting resin in a B-stage state (semi-cured state) or a thermoplastic resin that can be heated and melted, The insulating layer 120 is formed by curing this. The insulating layer 120 may have a single layer structure, or the electronic components 131 and 132 and the relay substrate 140 may be embedded using a plurality of resins. For example, the insulating layer 120 can be formed by filling a step generated by the electronic components 131 and 132 and the relay substrate 140 with a spacer and then pouring another resin into the gap.

  Next, as shown in FIG. 5, via holes 182a are formed in the insulating layer 120 by performing laser irradiation from the surface 120a side of the insulating layer 120, that is, from the side opposite to the core substrate 110. The via hole 182a is formed so that the terminal electrode 143 of the relay substrate 140 is exposed at the bottom. As already described, the via hole formed by laser irradiation has a tapered cross section, and the opening diameter on the laser irradiation side is larger than the opening diameter at the bottom. For this reason, if the depth of the via hole is deep, the opening diameter on the laser irradiation side is correspondingly increased, thereby limiting the formation pitch of the via hole. However, in this embodiment, since the depth of the via hole 182a is sufficient to reach the relay substrate 140, the opening diameter can be reduced as compared with the case where the via hole penetrating the insulating layer 120 is formed. . For this reason, even when the formation pitch of the terminal electrodes 143 is narrow, the via holes 182a can be correctly opened.

  Next, as shown in FIG. 6, the via hole conductor 182 is formed inside the via hole 182 a, and the wiring layer 163 is formed on the surface 120 a of the insulating layer 120. The method for forming the via-hole conductor 182 and the wiring layer 163 is not particularly limited. As a result, the wiring layer 163 is electrically connected to the electronic components 131 and 132 via the via-hole conductor 182, the relay substrate 140, and the wiring layer 161.

  Thereafter, as shown in FIG. 1, the semiconductor IC 150 is mounted on the core substrate 110, and the connection using the bonding wires 153 and the resin sealing are performed, whereby the electronic component built-in module 100 according to the present embodiment is completed.

  As described above, according to the manufacturing method according to the present embodiment, it is not necessary to form a via hole penetrating through the insulating layer 120 even though the insulating layer 120 is thick. As a result, the via hole formation pitch can be reduced.

  Next, a second preferred embodiment of the present invention will be described.

  FIG. 7 is a schematic cross-sectional view showing the structure of the electronic component built-in module 200 according to the second preferred embodiment of the present invention.

  As shown in FIG. 7, in the electronic component built-in module 200 according to the present embodiment, another core substrate 210 is provided on the surface 120 a of the insulating layer 120, and the via-hole conductor 182 penetrates the core substrate 210. The wiring layer 163 is provided not on the surface 120 a of the insulating layer 120 but on the surface of the core substrate 210. Since the other components are almost the same as those of the electronic component built-in module 100 shown in FIG. 1, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  Similar to the core substrate 110, the core substrate 210 is a high-strength substrate in which a core material is impregnated with a thermosetting resin, a thermoplastic resin, or the like. The material and thickness of the core substrate 210 may be the same as those of the core substrate 110. A wiring layer 163 is formed on one surface 210 a of the core substrate 210, and portions of the wiring layer 163 other than external terminals connected to a motherboard or the like are covered with a resist 172. The other surface 210 b of the core substrate 110 is in contact with the insulating layer 120.

  With this configuration, the electronic component built-in module 200 according to the present embodiment has higher mechanical strength of the entire module than the electronic component built-in module 100 shown in FIG. In addition, since the insulating layer 120 is sandwiched between the two core substrates 110 and 210, the module is less likely to warp due to a temperature change. Furthermore, since the wiring layer 163 is formed on the core substrate 210, it is necessary to form the wiring layer directly on the surface of the insulating layer 120 even when the adhesion between the wiring layer 163 and the insulating layer 120 is low. Disappear. For this reason, it becomes possible to improve the reliability of a product.

  Next, a method for manufacturing the electronic component built-in module 200 according to the present embodiment will be described.

  8 and 9 are process diagrams for explaining the method of manufacturing the electronic component built-in module 200 according to the present embodiment.

  First, after passing through the steps shown in FIGS. 2 to 4, as shown in FIG. 8, the core substrate 210 is attached to the surface 120 a of the insulating layer 120, and further, laser irradiation is performed from the core substrate 210 side, A via hole 182 a is formed in the core substrate 210 and the insulating layer 120. In this embodiment, since the via hole 182a needs to penetrate the core substrate 210, the depth of the via hole 182a is slightly deeper than that of the first embodiment. However, if the thickness of the core substrate 210 is set to 100 μm or less, the enlargement of the opening diameter on the laser irradiation side can be minimized.

  Next, as shown in FIG. 9, the via hole conductor 182 is formed inside the via hole 182 a, and the wiring layer 163 is formed on the surface 210 a of the core substrate 210. As a result, the wiring layer 163 is electrically connected to the electronic components 131 and 132 via the via-hole conductor 182, the relay substrate 140, and the wiring layer 161.

  After that, as shown in FIG. 7, the resist 172 is formed so that the external terminals connected to the motherboard etc. are exposed, and further, the semiconductor IC 150 is mounted, wire bonding, resin sealing, etc. are performed. The electronic component built-in module 200 according to the form is completed.

  Also in this embodiment, since it is not necessary to form via holes that penetrate the insulating layer 120, it is possible to reduce the formation pitch of the via holes. In addition, it is possible to obtain a module with higher strength compared to the first embodiment.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. Needless to say, it is included in the range.

  For example, in the present invention, it is not essential to incorporate a semiconductor IC in the relay substrate, and this may be omitted. Further, the number of relay boards incorporated in the insulating layer is not limited, and may be one as in the above embodiment, or may be two or more. When two or more relay boards are built in, these may be embedded in the same insulating layer, or may be embedded in different insulating layers. Further, when two or more relay boards are built in, they may be embedded in the thickness direction of the module. This is effective when the insulating layer is very thick.

  Further, the module according to the present invention may be used as a relay board by embedding the module according to the present invention in a higher-order module or a motherboard. In other words, it is possible to embed the relay board twice (or more).

  In the present invention, it is not essential to mount the semiconductor IC 150 on the surface of the module, and this may be omitted.

  Moreover, in the said embodiment, although the insulating layer 120 and the core board | substrate 110 have contact | connected directly, you may interpose another insulating layer and a core board | substrate between these. Similarly, in the second embodiment, the insulating layer 120 and the core substrate 210 are in direct contact, but another insulating layer or core substrate may be interposed therebetween. Furthermore, in the said embodiment, what impregnated the core material with the thermosetting resin, the thermoplastic resin, etc. is used as a core board | substrate, However, This invention is not limited to this. Further, the core substrate may be omitted.

  Furthermore, in the present invention, the method for forming a via hole in the insulating layer is not limited to laser irradiation, and other methods such as a sand blast method using a metal mask may be used. Since the via hole formed by the sandblast method has a tapered cross section, the effect of the present invention can be obtained.

1 is a schematic cross-sectional view showing the structure of an electronic component built-in module 100 according to a preferred first embodiment of the present invention. It is a schematic sectional drawing which shows one process (preparation of the core board | substrate 110) for manufacturing the electronic component built-in module 100. FIG. FIG. 6 is a schematic cross-sectional view showing one process (mounting of electronic components 131 and 132 and relay board 140) for manufacturing electronic component built-in module 100. It is a schematic sectional drawing which shows 1 process (formation of the insulating layer 120) for manufacturing the electronic component built-in module 100. FIG. It is a schematic sectional view showing one process (formation of via hole 182a) for manufacturing electronic component built-in module 100. FIG. 6 is a schematic cross-sectional view showing one process (formation of via-hole conductor 182 and wiring layer 163) for manufacturing electronic component built-in module 100. It is a schematic sectional drawing which shows the structure of the electronic component built-in module 200 by preferable 2nd Embodiment of this invention. It is a schematic sectional drawing which shows one process (formation of the via hole 182a) for manufacturing the electronic component built-in module 200. FIG. 11 is a schematic cross-sectional view showing one process (formation of via hole conductor 182 and wiring layer 163) for manufacturing electronic component built-in module 200.

Explanation of symbols

100, 200 Electronic component built-in module 110, 210 Core substrate 110a, 110b, 210a, 210b Core substrate surface 120 Insulating layer 120a, 120b Insulating layer surface 131, 132 Electronic component 133 Solder 140 Relay substrate 140a, 140b Surface of relay substrate 141 Semiconductor IC
142,143 Terminal electrode 144 Internal wiring 150 Semiconductor IC
151 Conductive paste 152 Pad electrode 153 Bonding wire 154 Sealing resin 161-163 Wiring layers 171, 172 Resist 181, 182 Via hole conductor 182a Via hole

Claims (6)

An insulating layer in which electronic components and a relay substrate are embedded;
A first wiring layer formed on one side as viewed from the insulating layer and electrically connected to the electronic component and the relay substrate;
A second wiring layer formed on the other side when viewed from the insulating layer;
A via-hole conductor that electrically connects the second wiring layer and the relay substrate,
The electronic component built-in module, wherein the first wiring layer and the second wiring layer are electrically connected through the relay substrate and the via-hole conductor.   2. The electronic device according to claim 1, further comprising a first core substrate disposed on the one side when viewed from the insulating layer, wherein the electronic component and the relay substrate are mounted on the first core substrate. The electronic component built-in module described in 1.   The electronic component built-in module according to claim 1, further comprising a second core substrate disposed on the other side when viewed from the insulating layer.   The electronic component built-in module according to claim 1, wherein a semiconductor IC is embedded in the relay substrate. Mounting an electronic component and a relay substrate on the first core substrate;
Embedding the electronic component and the relay substrate in the insulating layer by forming an insulating layer on the first core substrate;
Forming a via-hole conductor electrically connected to the relay substrate on the insulating layer from a side opposite to the first core substrate.   6. The method of manufacturing an electronic component built-in module according to claim 5, further comprising a step of forming a second core substrate on a side opposite to the first core substrate when viewed from the insulating layer.

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