JP2009158641A - Method of producing module with built-in component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of producing a module with built-in components for forming a hollow cavity which houses circuit components without being contacted with a resin layer while reducing the thickness of the resin layer. <P>SOLUTION: This production method includes: laminating an uncured first resin layer 10 having a penetrating opening part 11 on a cured second resin layer 20; mounting a first circuit component 5 on a wiring pattern 2a on a module substrate 1; confronting the uncured first resin layer 10 with the module substrate 1; and pressure-bonding the first resin layer 10 to the module substrate 1 and curing it so that the first circuit component 5 is housed in the opening part 11 in non-contact. Since the second resin layer 20 is not deformed, the first circuit component 5 is arranged within the hollow cavity in non-contact. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a method for manufacturing a component built-in module. The component built-in module in the present invention means a module having at least one component built-in layer in which a component is built in a resin layer, and has a plurality of component built-in layers or thin layers (components This includes modules with built-in layers that are not built in.

2. Description of the Related Art Conventionally, a component built-in module including a component built-in layer in which a circuit component is embedded in a resin layer is used in wireless devices such as mobile phones and automobile phones and other various communication devices. As a method of manufacturing this type of component built-in module, Patent Document 1 discloses that a circuit component is mounted on a substrate on which a wiring pattern is formed, and an uncured resin layer is pressure-bonded onto the circuit component and the substrate. A method has been proposed in which a circuit layer is embedded therein, the resin layer is cured, and then the substrate is peeled off.

Circuit components embedded in the insulating substrate include not only integrated circuit elements such as semiconductor integrated circuits but also peripheral passive components such as filters and capacitors. However, characteristics of circuit components such as MEMS elements and surface acoustic wave elements change when they come into contact with the resin layer, and therefore such circuit components cannot be embedded in the resin layer. Therefore, Patent Documents 2 and 3 propose a component built-in module in which a hollow cavity is formed inside a resin layer and a circuit component is arranged in the hollow cavity.

FIG. 4 shows a method of manufacturing the component built-in module disclosed in Patent Document 2. An uncured resin layer 30 having openings 31 and vias 32 is prepared, while a transfer film 33 on which a wiring pattern 34 is formed is prepared, and a circuit component 35 is mounted on the wiring pattern 34. Next, the uncured resin layer 30 is pressure-bonded to the transfer film 33 on which the circuit component 35 is mounted so that the opening 31 corresponds to the circuit component 35, and the wiring pattern 34 and the via 34 of the resin layer 30 are connected. Connect. Further, the transfer film 33 is peeled from the uncured resin layer 30. Thereafter, the uncured resin layers 36 and 37 are pressed on and under the resin layer 30, and the three resin layers 30, 36, and 37 are thermally cured at the same time, so that the circuit component 35 is accommodated in the opening 31. Get a built-in module.

In the case of this method, it is necessary to strongly press the upper and lower resin layers 36 and 37 against the central resin layer 30 in order to ensure airtightness between the central resin layer 30 and the upper and lower resin layers 36 and 37. is there. Therefore, the resin layer is distorted as shown in FIG. 5, and in particular, the lower resin layer 37 may be deformed toward the opening 31, and the resin layer 37 may contact the circuit component 35. If the thickness of the central resin layer 20 is sufficiently increased, there is no risk of contact, but this has the disadvantage that the thickness of the component built-in module is increased. In addition, since the circuit component 35 is supported only by the wiring pattern 34 at the stage of FIG. 4B, the support strength is very low, and when the resin parts 36 and 37 are bonded to each other in FIG. There is a risk that the wiring pattern 34 is disconnected.

FIG. 6 shows a method of manufacturing the component built-in module disclosed in Patent Document 3. In this method, wiring patterns 41 and 42 are first formed on the front and back surfaces of the cured substrate 40, and a circuit component 43 is mounted on the wiring pattern 41 on the front surface. Next, a sealing material 44 is formed on the bump portion of the circuit component 43, and uncured resin layers 45 and 46 are pressure bonded to the front and back surfaces of the substrate 40. A recess 45a is formed in advance in the resin layer 45 to be pressure-bonded to the surface of the substrate 40, and the circuit component 43 is accommodated in the recess 45a.

In this case, since the circuit component 43 is mounted on the wiring pattern 41 of the cured substrate 40, the supporting strength thereof does not decrease. However, when the uncured resin layer 45 is pressure-bonded to the substrate 40, the bottom of the recess 45a may be bent and contact the circuit component 43 as shown in FIG. If the depth of the recess 45a is sufficiently deep, the possibility of contact is reduced, but there is a disadvantage that the thickness of the resin layer 45 is increased accordingly.
Japanese Patent Laid-Open No. 11-220262 Japanese Patent Laid-Open No. 11-45955 JP 2004-31651 A

Accordingly, an object of the present invention is to provide a method of manufacturing a component built-in module that can form a hollow cavity that can accommodate a circuit component without contacting the resin layer while reducing the thickness of the resin layer.

The method for manufacturing a component built-in module according to the present invention includes a first step of preparing an uncured first resin layer having a penetrating opening and a second step of preparing a cured second resin layer. And a third step of laminating the uncured first resin layer and the cured second resin layer, and a substrate having a wiring pattern formed on the top surface, A fourth step of mounting circuit components, and a step of pressing the uncured first resin layer and the cured second resin layer laminated in the third step onto the substrate, A fifth step of pressure-bonding the uncured first resin layer so as to face the substrate and storing the first circuit component in the opening in a non-contact manner; and And a sixth step of curing the first resin layer.

An uncured first resin layer having a penetrating opening is prepared, and the first resin layer is pressure-bonded to the cured second resin layer and laminated. During the lamination, the first resin layer may be heated and pressurized at a temperature at which the first resin layer is not cured. In the laminating stage, the first resin layer remains uncured. The uncured state is preferably, for example, a B-stage state or a softer state. Next, a substrate having a wiring pattern formed on the upper surface is prepared, and a first circuit component is mounted on the wiring pattern. As the substrate, a printed wiring board having a wiring pattern formed on the surface can be used. The wiring pattern includes mounting lands for mounting circuit components, via lands, wiring for connecting lands to each other, and the like. The first circuit component is a component whose characteristics change when it comes into contact with the resin layer. In this manner, the first resin layer and the second resin layer that are stacked are bonded to the substrate on which the first circuit component is mounted with the uncured first resin layer facing the substrate. At this time, the first resin layer is in close contact with the wiring pattern of the substrate, and the first circuit component is accommodated in the opening without contact. The first resin layer is crimped and distorted, but the bottom of the opening is composed of a cured second resin layer, so the bottom of the opening does not deform toward the circuit component, Contact with circuit components can be avoided. After the pressure bonding, when the first resin layer is cured, the first circuit component is enclosed in the hollow cavity of the cured resin layer.

Since the second resin layer is a cured resin plate, the second resin layer 20 is not deformed when the first resin layer is pressed. Therefore, if the compression margin of the first resin layer is managed so that the distance between the substrate and the second resin layer is not less than the height of the first circuit component, the second resin layer and the first circuit are controlled. Contact with parts can be reliably prevented. In addition, since the bottom wall of the opening does not bend when the first resin layer is crimped, the thickness of the first resin layer may be a minimum thickness for forming the hollow cavity, and the component built-in module is made thin. it can. Moreover, since the cured second resin layer has a role of supporting the back surface of the uncured first resin layer, the hollow cavity can be prevented from being deformed due to the flow of the first resin layer, and the first resin layer can be suppressed. And contact with the first circuit component can also be prevented.

Prior to the fifth step of pressure bonding the uncured first resin layer on the substrate, the second circuit component different from the first circuit component is mounted on the wiring pattern formed on the substrate, When the uncured first resin layer is pressure-bonded onto the substrate, the second circuit component may be embedded in the uncured first resin layer. Unlike the first circuit component, the second circuit component is a component whose characteristics do not change or hardly change even when it comes into contact with a resin such as a chip capacitor or chip resistor. When the second circuit component is embedded in the first resin layer, the resin flows excessively by the volume of the second circuit component, and the opening is easily deformed. This is particularly noticeable when the second circuit component is disposed adjacent to the first circuit component. However, in the present invention, since the first resin layer is lined with the cured second resin layer, deformation of the opening can be suppressed, and contact between the resin and the first circuit component can be prevented.

In the first step, the opening can be formed by irradiating a laser to the uncured first resin layer. There are various methods such as drilling and punching as a method for forming the opening in the first resin layer. When a hole is formed by laser irradiation, an opening that penetrates accurately and easily can be formed. In this case, if the uncured first resin layer is formed on the carrier film, the opening can be formed together with the carrier film by laser irradiation.

After the sixth step, it is preferable to further include a step of forming vias having the wiring pattern as a bottom surface in the first resin layer and the second resin layer. Vias enable three-dimensional wiring. Vias can be easily formed by laser processing. Since both the first resin layer and the second resin layer are cured, the desmear process after via processing is simplified.

The first resin layer and the second resin layer may be made of different materials. However, if they are made of the same kind of material, the thermal expansion coefficient is the same, warpage and cracking hardly occur, and parts with stable characteristics. Built-in module can be configured.

As described above, according to the method for manufacturing a component built-in module according to the present invention, the uncured first resin layer having the opening and the cured second resin layer are laminated, and this laminate is formed into a circuit. Since the hollow cavity is formed around the circuit component by press-bonding to the substrate on which the component is mounted, the deformation of the opening can be suppressed by the cured second resin layer. In particular, since the bottom of the hollow cavity is composed of the hard second resin layer, the bottom of the hollow cavity is not deformed when the first resin layer is crimped, and the circuit component and the resin layer are in contact with each other. Can be prevented. As described above, since the deformation of the first resin layer can be suppressed by the second resin layer, it is not necessary to increase the thickness of the first resin layer more than necessary, and a thin component built-in module can be configured.

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

FIG. 1 shows a first embodiment of a component built-in module according to the present invention. The component built-in module A includes a module substrate 1 made of an insulating substrate such as a resin substrate or a ceramic substrate. Here, a printed wiring board made of a resin substrate having a single-layer structure is used as the module substrate 1, but a multilayer wiring substrate may be used. Wiring patterns 2 a and 2 b are formed on a part of the upper surface of the module substrate 1. Among them, a mounting land 2a for mounting the first circuit component 5 is formed at the center of the module substrate 1, and the second circuit component 6 is mounted around the mounting land 2a adjacent to the mounting land 2a. A mounting land 2b for this purpose is formed. The lands 2a and 2b are connected to the wiring electrodes 4a and 4b on the lower surface of the module substrate 1 through via conductors 3a and 3b, respectively. In the present embodiment, the wiring electrodes 4a and 4b also serve as terminal electrodes of the component built-in module A. A first circuit component 5 whose characteristics change when it comes into contact with a resin layer such as a MEMS element or a surface acoustic wave element is mounted on the mounting land 2a of the module substrate 1, and the mounting land 2b A second circuit component 6 is mounted that does not change its characteristics even when it comes into contact with the resin layer, such as a chip component. The mounting method may be any method such as soldering, mounting using a conductive adhesive, flip chip mounting using bumps, or precoat mounting.

Two resin layers 10 and 20 are laminated on the module substrate 1 and fixed together. These resin layers 10 and 20 are made of, for example, a thermosetting resin, a mixture of a thermosetting resin and an inorganic filler, a resin composition in which a glass fiber is impregnated with a thermosetting resin, or the like. The resin layers 10 and 20 are preferably made of the same material as each other, and more preferably made of the same material as the module substrate 1 or a material having a thermal expansion coefficient close to that of the module substrate 1. An opening 11 is formed in the first resin layer 10, and a hollow cavity 21 is formed by the opening 11 and the second resin layer 20 constituting the upper bottom surface thereof, and the first circuit component is formed in the hollow cavity 21. 5 is accommodated in a non-contact state with the resin layers 10 and 20. The gap δ between the top surface of the first circuit component 5 and the resin layer 20 is 0.02 to 0.03 mm. On the other hand, the second circuit component 6 is embedded in the first resin layer 10. The second resin layer 20 is formed of a flat plate having a flat surface. In FIG. 1, the thickness of the second resin layer 20 is set to be equal to the thickness of the first resin layer 10, but may be thinner than the first resin layer 10. By reducing the thickness of the second resin layer 20, the overall height of the component built-in module A can be reduced.

Next, an example of a manufacturing method of the component built-in module A having the above configuration will be described with reference to FIG. Here, the manufacturing method of the component built-in module A in the sub-board state will be described, but in actuality, it is manufactured in a collective board state in which a plurality of sub-boards are assembled and then divided into the sub-boards.

As shown in FIG. 2A, first, an uncured first resin layer 10 having an opening 11 penetrating in the front and back direction and a cured flat plate-like second resin layer 20 are prepared. The opening 11 can be easily formed by irradiating the first resin layer 10 with a laser. The method of forming the opening 11 is not limited to laser processing, and various methods such as cutting using a drill and molding by punching are conceivable. Here, the opening 11 has a tapered through hole whose diameter increases upward, but a straight through hole may be used. Next, as shown in FIG. 2B, the uncured first resin layer 10 is pressure-bonded and fixed to the cured second resin layer 20. At this time, you may heat in the temperature range in which the 1st resin layer 10 does not harden | cure. Thus, although the laminated body of the 1st resin layer 10 and the 2nd resin layer 20 is obtained, the 1st resin layer 10 still remains uncured.

Next, as shown in FIG. 2C, the module substrate 1 is prepared, and a laminated body in which the first resin layer 10 and the second resin layer 20 are laminated is disposed thereon. Circuit components 5 and 6 are mounted on the lands 2a and 2b of the module substrate 1, respectively. Next, as shown in FIG. 2D, the opening 11 and the circuit component 5 are aligned, and the uncured first resin layer 10 is pressure-bonded toward the module substrate 1. At this time, if heating and pressurizing at a temperature higher than the temperature at which the first resin layer 10 is cured, pressure bonding and curing can be performed in one step. The first resin layer 10 is brought into close contact with the wiring pattern on the upper surface of the module substrate 1 by pressure bonding, and the first circuit component 5 is accommodated in the opening portion 11 in a non-contact manner. Embedded in the resin layer 10. The first resin layer 10 is compressed and distorted, and the resin flows by the volume of the second circuit component 6, so that the opening 11 is easily deformed, but the upper bottom surface of the opening 11 has been cured. Therefore, the upper bottom surface of the opening 11 remains a flat surface and is not deformed, and contact with the first circuit component 5 can be avoided. When the first resin layer 10 is thermally cured, the first circuit component 5 is enclosed in the hollow cavity 21 of the resin layers 10 and 20 in a non-contact manner, and the component built-in module A shown in FIG. 1 is obtained. Therefore, the characteristics of the first circuit component 5 do not deteriorate.

Since the second resin layer 20 is a cured resin plate, the second resin layer 20 does not deform during thermocompression bonding. Therefore, if the compression margin of the first resin layer 10 is managed so that the distance L between the module substrate 1 and the second resin layer 20 is not less than the height H of the first circuit component 5, the second Contact between the resin layer 20 and the first circuit component 5 can be reliably prevented. When a resin layer having an opening portion having an uncured bottom surface is pressure-bonded as in the conventional case, the bottom portion of the opening portion may come into contact with the circuit component. For safety, the depth of the opening portion (the thickness of the resin layer) However, in the present invention, since the bottom surface of the opening is not deformed as described above, dimensional management in the crimping process is facilitated.

In the case where a tapered through hole is formed as the opening 11 as in the present embodiment, the first resin layer 10 and the second resin layer 20 are in contact with each other in a direction in which the diameter of the through hole is small. The second resin layer 20 is preferably laminated. As described above, the bottom wall of the opening 11 facing the second resin layer 20 is less likely to be deformed. That is, it is easier to prevent contact between the first resin layer 10 and the first circuit component 5 by increasing the diameter of the opening 11 on the side opposite to the second resin layer 20 which is likely to be deformed. Become.

FIG. 3 shows a first embodiment of a component built-in module according to the present invention. Since the basic structure of the component built-in module B is the same as that of the component built-in module A of the first embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted. In the component built-in module B of this embodiment, as shown in FIG. 3A, via lands 7 are formed on a part of the module substrate 1, and the lands 7 are wiring electrodes on the lower surface via via conductors 3c. 4c. After the circuit components 5 and 6 are mounted on the module substrate 1, a laminate having the uncured first resin layer 10 and the cured second resin layer 20 is disposed on the module substrate 1.

Next, as shown in FIG. 3B, the uncured first resin layer 10 is thermocompression bonded toward the module substrate 1 to cure the first resin layer 10. In this state, the first circuit component 5 is sealed without contact in the hollow cavity 21, and the second circuit component 6 is embedded in the first resin layer 10. After the first resin layer 10 is cured, a laser is irradiated from above the second resin layer 20 to form a via hole 8a having the land 7 as a bottom surface. At this time, due to the reflection from the land 7, the via hole 8a becomes a tapered hole whose diameter is reduced downward. Smear generated during laser processing is removed by desmear treatment.

Thereafter, the via conductor 8 is formed by filling and curing the conductive paste in the via hole 8a. After the via conductor 8 is formed, the wiring electrode 9 is formed on the upper surface of the second resin layer 20 to electrically connect the via land 7 and the wiring electrode 9 on the upper surface of the second resin layer 20. Can do. The via land 7 need not be connected to the wiring electrode 4c on the lower surface, and may be connected to the other lands 2a and 2b.

The present invention is not limited to the above embodiment. In the said Example, although the 2nd resin layer 20 was comprised with the flat resin board which does not have a wiring pattern, the wiring board which has a wiring pattern in a main surface or an inside may be sufficient. The component built-in module of the present invention is not limited to the three-layer structure of the module substrate 1, the first resin layer 10, and the second resin layer 20, and another resin is provided on the second resin layer 20. A layer or a wiring board may be laminated, or another resin layer or a wiring board may be laminated on the lower side of the module substrate 1.

It is sectional drawing of 1st Example of the component built-in module which concerns on this invention. It is a manufacturing-process figure of the component built-in module shown in FIG. It is a manufacturing-process figure of 2nd Example of the component built-in module which concerns on this invention. It is a manufacturing process figure of an example of the conventional component built-in module. It is a figure which shows the deformation | transformation of the resin layer in the manufacturing process shown in FIG. It is a manufacturing process figure of the other example of the conventional component built-in module. It is a figure which shows the deformation | transformation of the resin layer in the manufacturing process shown in FIG.

Explanation of symbols

A, B Module with built-in components 1 Module board (board)
2a, 2b Mounting land (wiring pattern)
3a, 3b Via conductors 4a, 4b Wiring electrode 5 First circuit component 6 Second circuit component 10 First resin layer 11 Opening portion 20 Second resin layer 21 Hollow cavity

Claims (4)

A first step of preparing an uncured first resin layer having an opening therethrough;
A second step of preparing a cured second resin layer;
A third step of laminating the uncured first resin layer and the cured second resin layer;
A fourth step of preparing a substrate having a wiring pattern formed on the upper surface, and mounting a first circuit component on the wiring pattern;
A step of pressure-bonding the uncured first resin layer and the cured second resin layer laminated in the third step to the substrate, wherein the uncured first resin layer is A fifth step of crimping the first circuit component so as to face the substrate and be accommodated in the opening in a non-contact manner;
And a sixth step of curing the first resin layer after the fifth step. In parallel with the fourth step, a step of mounting a second circuit component on a wiring pattern formed on the substrate,
The method of manufacturing a component built-in module according to claim 1, wherein in the fifth step, the second circuit component is embedded in the uncured first resin layer. 3. The method of manufacturing a component built-in module according to claim 1, wherein in the first step, the opening is formed by irradiating a laser to the uncured first resin layer. 4. 4. The method according to claim 1, further comprising a step of forming a via having the wiring pattern as a bottom surface in the first resin layer and the second resin layer after the sixth step. 5. A method for producing the component built-in module according to the item.

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