JP2006156482A - Circuit module and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce size, by improving the mounting efficiency by building into a multilayer structure and to increase the reliability by having a functional element body operate stably. <P>SOLUTION: The functional element body 5 is sealed in the layer of the multilayered structure of a module board 2 and a wiring board 4 which are stacked via a prepreg 3, in such a manner that a functional surface 5a formed with a movable portion 5b may face a concave portion 6. The functional element body 5 is built in and shielded, between the first shield pattern 12 of the module board 2 and the second shield pattern 18 of the wiring board 4, which are interlayer-connected by a grounding via 19 extending through the prepreg 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a circuit module body in which a functional element body having a movable portion provided on a functional surface is sealed in a functional element body housing space formed in an inner layer of a mounting substrate, and a method for manufacturing the circuit module body.

  In recent years, various mobile electronic devices such as personal computers, mobile phones, video devices, audio devices, and the like have been reduced in size and weight, increased in functionality, increased in functionality, and increased in speed. In mobile electronic devices and the like, a mounting substrate having a wiring layer having a fine wiring pattern formed in multiple layers for high density wiring is used for this purpose, and the mounting substrate is small and multifunctional. A circuit module body in which the integrated circuit component, the electronic component, or various semiconductor device components are mounted by a surface mounting method such as a flip chip mounting method is provided.

  For example, in mobile phones and the like, in order to cope with further miniaturization, cost reduction, and multi-functionality, for example, SiGe bipolar CMOS technology suitable for high-frequency analog circuits, a low IF method, a direct conversion method, etc. are studied. It is being advanced. In the low IF method, the IF frequency (intermediate frequency) is set to 100 kHz to 150 kHz, which is lower than the conventional 100 M to 200 MHz, and the IF filter is integrated as a band pass filter to provide an external surface acoustic wave filter element (SAW: Surface Acoustic). The Wave Device) filter is unnecessary, and it aims to realize one chip.

  In the low IF method, for example, an RF circuit module 100 showing only a reception system is provided in FIG. The RF circuit module 100 includes an RF filter 102 that passes an RF signal in a predetermined frequency band received by the antenna 101, an LNA (low noise amplifier) 103, an RF mixer 104, a 90 ° phase shifter 105, a VCO (local oscillator) 106, An IF filter 107, an IF mixer 108, a VGA (gain conversion amplifier) 109, an anti-aliasing filter 110, an AD converter 111, a demodulated signal processing circuit 112, and the like are main components. In the RF circuit module 100, the IF filter 106 is mainly composed of a SAW filter.

  Further, the direct conversion method omits the conversion of the RF signal into the IF frequency and directly converts it into the baseband signal, thereby making it possible to reduce components such as channel selection IF filters and IF mixers. In the direct conversion method, as in the RF circuit module 120 showing only the reception system in FIG. 11, the RF signal received by the antenna 121 is directly supplied to the LNA 122 and controlled by the 90 ° phase shifter 124 and the VCO (local oscillator) 125. The RF signal that has passed through the RF mixer 123 is supplied to the demodulated signal processing circuit 130 via the low-pass filter 126, the VGA 127, the anti-aliasing filter 128, and the AD converter 129.

  By the way, as a circuit module body, for example, a semiconductor device is mounted on a mounting substrate by directly mounting a so-called bare chip in a non-package state from a mounting method through a terminal piece protruding from a resin mold or a ceramic package. An implementation method that aims to make it easier is also adopted. In the circuit module body, connectors such as solder bumps are provided in advance on a large number of element mounting electrodes formed on the mounting substrate, and the combined bare chip is mounted on the mounting substrate.

  The circuit module body enables high-density mounting of electronic components and semiconductor devices by reducing the mounting area and increasing the number of pins by making the mounting area of the mounting substrate approximately the same as the chip size. . In addition, the circuit module body realizes high-speed signal transmission and high frequency by shortening the wiring length with less loss. In a circuit module body, a bare chip mounted on a mounting substrate is sealed with an insulating resin so that insulation and mechanical protection from other mounting components can be achieved.

  Various high-frequency circuit module bodies including the above-mentioned low-IF and direct conversion circuit modules incorporate various passive elements, and electronic components, semiconductor circuit components, or various functional element bodies are mounted on the module substrate. . For example, filter elements such as the SAW filter element and bulk acoustic wave device (BAW) described above, micro electro mechanical systems (MEMS), and piezoelectric thin film resonant elements (FBAR). Are provided with a vibrator and a movable element on the functional surface.

  When such a functional element is mounted on a module substrate in a bare chip state and sealed with a resin, the vibrator or the like is fixed and becomes inoperable. In addition, such a functional element may change in characteristics due to the influence of a temperature change or an etching solution applied to a fine vibrator or the like during a packaging process or a circuit module manufacturing process. Further, such a functional element has a problem in that the vibrator and the like are affected by the external environment, or the electrical characteristics and functional characteristics change due to charging by static electricity or the like, and the life is deteriorated due to oxidation. Therefore, in such a functional element, a special configuration is employed in which the chip element is sealed in a package having a hollow structure and the hollow portion is maintained in a vacuum or an inert gas atmosphere. Such a functional element is mounted on a mounting substrate via a resin package, thereby reducing mounting efficiency.

  The applicant previously provided a semiconductor device in which a bare chip filter chip having no resin package is mounted on a carrier substrate according to Patent Document 1. The prior application semiconductor device mounts the filter chip so as to straddle the recessed portion formed on the main surface of the carrier substrate, and forms a wiring layer that seals the outer periphery of the filter chip. Is sealed with a metal plate.

  Further, in Patent Document 2, an insulating resin frame and a connection bump that surround an active surface of a chip to form an adhesive layer are provided, and the chip is face-down mounted on a mounting substrate (surface) with the active surface as an opposing surface. A micro package structure to be mounted) is disclosed. In such a micro package structure, a hollow portion surrounded by an insulating resin frame is formed between the active surface of the chip and the main surface of the mounting substrate. According to such a micro package structure, a chip having an active surface with respect to a mounting substrate can be face-down mounted in the same manner as other electronic components and bare chips. Therefore, according to such a micro package structure, the module is made thinner and the efficiency of the mounting process is improved.

JP 2000-114413 A Japanese Patent No. 3514349

  By the way, the semiconductor device disclosed in Patent Document 1 described above mainly aims to improve characteristics and reliability by reducing the parasitic inductor of the filter chip mounted on the carrier substrate and easily performing heat dissipation and grounding. Objective. The purpose of the semiconductor device is not to encapsulate the functional element body in the inner layer and to make the above-described RF circuit module or the like into one module by multilayering.

  Further, in the micropackage disclosed in Patent Document 2, it is effective in reducing the thickness, but the chip itself is large because a chip is provided with a region for forming connection bumps and a region for forming a frame-shaped insulating resin layer. Turn into. In the micro package, it is possible to mount the chip in the area almost the same as the external dimensions with respect to the mounting board. However, due to the increase in size of this chip, it cannot contribute much to the miniaturization of the entire module. . In addition, in the micro package, since the chip is mounted in an open state, there is a problem that reliability is lowered due to the influence of moisture and oxidation.

  On the other hand, in the above-described RF circuit module, a comparatively large component such as a VCO, a component around an antenna, an LNA or a mixer made into one chip, or other chip components or electronic components are mounted, and a passive element such as a resistor or a capacitor is mounted. Therefore, it is essential to increase the number of layers and to reduce the number of mounted parts on the surface. Furthermore, in the RF circuit module, a shield structure that does not increase the size of the chip components mounted in the wiring layer and avoids the influence on the internal lines and the circuit section by a simple configuration and blocks external noise. Is also essential.

  SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a circuit module body and a method for manufacturing the circuit module body that improve the mounting efficiency by multilayering, reduce the size, and improve the reliability by the stable operation of the functional element body. .

  A circuit module body according to the present invention that achieves the above-described object includes a multilayer wiring board, a functional element body, a prepreg, and a wiring board. In the multilayer wiring board, wiring patterns are formed in multiple layers via an insulating layer, a recessed portion exposing the first shield pattern formed in the inner layer at the bottom on the first main surface, and a region surrounding the recessed portion A wiring pattern having a large number of element mounting electrodes arranged in an array is formed. The functional element body is, for example, a SAW filter element, a BAW filter element, a MEMS element, or an FBAR element. A movable portion and input / output electrodes are provided on the functional surface, and the functional surface is a mounting surface on the first main surface of the multilayer wiring board. The input / output electrodes are connected to the opposing device mounting electrodes and mounted. The prepreg has a thickness substantially equal to the thickness of the functional element body and an opening substantially equal to the outer shape of the functional element body. The prepreg is formed on the first main surface of the multilayer wiring board so as to accommodate the functional element body in the opening. Be joined. The wiring board has a second shield pattern formed in a portion facing the functional element body, and seals the functional element body by closing the opening and combining the prepreg and the multilayer wiring board via the prepreg. Integrated. In the circuit module body, the first shield pattern of the multilayer wiring board and the second shield pattern of the wiring board are interlayer-connected by an earth via formed so as to penetrate the prepreg, and the functional element body includes the first shield pattern and the second shield. It is sealed and shielded by an inner layer sandwiched between patterns.

  In the circuit module body, the built-in functional element body can operate the movable part provided on the functional surface facing the recessed part formed in the multilayer wiring board and be kept airtight. In order to eliminate the influence of the external environment and perform stable operation. In the circuit module body, the functional element body that is sandwiched between the first shield pattern and the second shield pattern that are interlayer-connected through the earth via avoids the influence on the internal line, the circuit unit, and the like. At the same time, it is shielded from external noise. In the circuit module body, since the functional element body is built in, a mounting space is secured on the main surface of the multilayer wiring board or the wiring board, and electronic parts, chip parts, and the like are mounted.

  In addition, the circuit module body manufacturing method according to the present invention that achieves the above-described object includes a multilayer wiring board manufacturing process, a functional element body mounting process, a prepreg lamination process, a wiring board manufacturing process, and a wiring board bonding process. And a ground via forming step to manufacture a circuit module body. In the multilayer wiring board manufacturing process, a multilayer wiring board technology is used to form wiring patterns in multiple layers through an insulating layer using an organic insulating substrate as a base material, and a first shield formed on an inner layer at the bottom on the first main surface. A multilayer wiring board is produced in which a recessed portion exposing the pattern and a wiring pattern having a large number of element mounting electrodes arranged in a region surrounding the recessed portion are manufactured. The functional element assembly mounting process is performed by combining the first main surface of the multilayer wiring board with the functional surface as the mounting surface so as to cover the recessed portion, and connecting the input / output electrodes to the opposing element mounting electrodes. Mount the element body. In the prepreg laminating step, a prepreg having an opening substantially equal to the outer shape of the functional element body is laminated on the first main surface of the multilayer wiring board so that the functional element body is accommodated in the opening. In the wiring substrate manufacturing process, the first wiring pattern having the second shield pattern on the first main surface is formed by using the organic insulating substrate as a base material by the wiring substrate technology, and the second wiring pattern is formed on the second main surface. Fabricate the wiring board. In the wiring board bonding step, the wiring board is cured by applying a heat pressing process after closing the opening on the prepreg so that the second shield pattern faces the functional element body accommodated in the opening. And integrated with the multilayer wiring board through the prepreg. In the earth via forming step, an earth via for connecting the first shield pattern of the multilayer wiring board and the second shield pattern of the wiring board to each other is formed.

  In the method of manufacturing a circuit module body, a circuit module body in which a functional element body is sealed in an inner layer between a first shield pattern that is interlayer-connected by an earth via formed through a prepreg and a second shield pattern of a wiring board. To manufacture. In the method of manufacturing a circuit module body, the built-in functional element body can operate the movable part provided on the functional surface facing the recessed part formed in the multilayer wiring board, and maintains an airtight state. As a result, a circuit module body that eliminates the influence of the external environment and performs stable operation is manufactured. In the method of manufacturing a circuit module body, the functional element body sandwiched between the first shield pattern and the second shield pattern avoids the influence on the internal line, the circuit part, etc. and also from external noise. A circuit module body that is cut off and improved in reliability is manufactured. In the method of manufacturing a circuit module body, a circuit that can be miniaturized and multi-functionalized by mounting electronic components and chip components on the main surface of a wiring board that has a mounting space secured by incorporating a functional element body. A module body is manufactured.

  According to the present invention, a multilayer wiring board and a wiring board are laminated via a prepreg, and the interlayer shield is formed between the first shield pattern and the second shield pattern of the wiring board, which are connected by an earth via formed through the prepreg. A circuit module body is configured in which a functional element body is sealed in a layer in a bare chip state with a functional surface provided with a movable portion facing a recessed portion formed on a multilayer wiring board and kept in an airtight state. Therefore, according to the present invention, the functional element body eliminates the influence of the external environment, avoids the influence on the internal line, the circuit unit, etc., and is also cut off from the external noise to perform a stable operation and improve the reliability. And longer life. According to the present invention, the functional element body is reduced in space and mounted on the inner layer, and the component mounting space is secured on the main surface of the multilayer wiring board or the wiring board, so that downsizing and multi-functionalization can be achieved.

  Hereinafter, a circuit module body 1 shown as an embodiment of the present invention and a manufacturing method thereof will be described in detail with reference to the drawings. The circuit module body 1 is a high-frequency circuit module body mounted on a mounting board provided in, for example, a mobile phone or a personal computer. The circuit module body 1 has a module substrate 2 and a prepreg 3 interposed between the module substrate 2 and the module substrate 2 as shown in FIG. A multilayer wiring board body is constituted by the wiring board 4 laminated in this manner, and a so-called bare chip functional element body 5 not sealed with an insulating resin material is sealed in the layer of the multilayer wiring board body.

  In the circuit module body 1, the module substrate 2 is a substrate material excellent in heat resistance, chemical resistance or processability, such as liquid crystal polymer, glass epoxy, polyimide, polyphenylene ether, bismaletotriazine, polytetrafluoroethylene, or high frequency. An organic insulating substrate such as a butadiene resin is used as a base material, and a multilayer wiring substrate in which wiring patterns are formed in multiple layers via an insulating layer by a conventionally known multilayer wiring substrate technique. Although not described in detail, the module substrate 2 is formed with multilayers of appropriate wiring layers constituting a high-frequency transmission / reception circuit section, a power supply circuit section, a matching circuit section of the functional element body 5 and the like on the inner layer.

  As shown in FIGS. 1 and 2, the module substrate 2 is formed with a recessed portion 6 having an opening dimension smaller than the outer dimension of the functional element body 5 and a predetermined depth on the first main surface 2 a. On the module substrate 2, a first wiring pattern 8 having a large number of functional element mounting electrodes 7 arranged so as to surround the recessed portions 6 is formed on the first main surface 2 a. In the module substrate 2, the first wiring pattern 8 has lands 8 b and the like that are connected to the ground pattern 8 a and the wiring substrate 4 side together with the functional element body mounting electrodes 7. In the module substrate 2, a region surrounding the recessed portion 6 of the first main surface 2a is configured as a functional element body mounting region 9, and the functional element body 5 is mounted on the functional element body mounting region 9 as described later. It is connected to the electrode 7 for mounting.

  The recessed portion 6 is filled with a vacuum or an inert gas by performing a functional element body mounting process, a prepreg bonding process, or a wiring board lamination process, which will be described in detail later, in a vacuum or an inert gas atmosphere. The recessed portion 6 allows the functional element body 5 mounted on the functional element body mounting area 9 to have its functional surface 5a facing the internal space, thereby enabling a predetermined operation and suppressing the influence of the external environment and oxidation. So that stable operation and long life can be achieved.

  The module substrate 2 has a large number of external connection electrodes on the second main surface 2b side through which electrical signals are input and output through electrical connection with electrodes on the mounting board (not shown) on which the circuit module body 1 is mounted. A second wiring pattern 10 having 10a and a ground pattern 10b is formed. A first shield pattern 12 is formed on the inner layer of the module substrate 2. The first shield pattern 12 is formed so as to face the entire area of the functional element body mounting region 9, and a part of the first shield pattern 12 is exposed at the bottom of the recessed portion 6 and faces outward as shown in FIG. 2. In the module substrate 2, the first shield pattern 12 is connected to the ground pattern 8 a of the first wiring pattern 8 of the outer layer and the ground pattern 10 b of the second wiring pattern 10 through the via 11.

  By forming the first shield pattern 12, the ground pattern 8a, or the ground pattern 10b, the module substrate 2 configures a line pattern formed at a portion facing these forming portions via an insulating layer as a microstrip line. . Although details are omitted for the module substrate 2, the first wiring pattern 8, the second wiring pattern 10, or the inner layer pattern are appropriately interlayer-connected by vias (not shown).

  As shown in FIG. 3, the circuit module body 1 includes a SAW element (surface acoustic wave element) having a fine vibrator 5 b on a functional surface 5 a as a functional element body 5. The circuit module body 1 includes not only a SAW element but also a movable part on a functional surface such as a BAW element (bulk elastic wave element), a MEMS chip (microelectronic mechanical component chip), an FBAR element (piezoelectric thin film resonant element), etc. You may make it incorporate the functional element body which has. Further, the circuit module body 1 may be configured such that a plurality of functional element bodies 5 are sealed in a layer with the same configuration.

  The functional element body 5 has an outer dimension larger than the opening dimension of the recessed portion 6 formed on the module substrate 2 side as described above, and the functional surface along the outer peripheral edge over the opening edge of the recessed portion 6. A large number of input / output electrodes 13 are provided on 5a so as to face each functional element body mounting electrode 7 respectively. The functional element body 5 is provided with gold bumps 14 formed on each input / output electrode 13 by, for example, a ball bump forming method using a gold wire, an additive method such as a plating method or a printing method.

  The functional element body 5 is mounted on the functional element body mounting area 9 of the module substrate 2 so as to cover the recessed portion 6 by a functional element body mounting process described later. As shown in FIG. 1, the functional element body 5 is combined with the functional surface 5 a facing the recessed portion 6, and each functional element body mounting electrode to which each input / output electrode 13 faces by being subjected to a heat pressing process. 7 and gold bumps 14 are connected by a flip chip mounting method. As shown in FIG. 1, the functional element body 5 can perform a predetermined vibration operation when the vibrator 5 b provided on the functional surface 5 a faces the recessed portion 6. By mounting the functional element body 5 on the first main surface 2a of the module substrate 2, the vibrator 5b and the first shield pattern 12 exposed at the bottom of the recessed portion 6 are maintained at a predetermined interval. The parasitic capacitance is reduced and stable operation is performed.

  The functional element body 5 may be improved in mechanical strength by filling and fixing an underfill material to each joint portion between the input / output electrode 13 and the functional element body mounting electrode 7. In addition, the functional element body 5 may be mounted on the module substrate 2 by, for example, reflow soldering by joining solder balls to the input / output electrodes 13.

  As is well known, the prepreg 3 is an insulating adhesive sheet that is used in the multilayer wiring board technology when a plurality of wiring boards are laminated together or an insulating layer is formed on the wiring layer. The prepreg 3 is made of, for example, a semi-curable sheet material obtained by impregnating a glass cloth of a reinforcing material with a thermosetting resin, has a thickness substantially equal to the thickness of the functional element body 5 and has an opening as shown in FIG. 15 is formed. The opening 15 is formed so as to penetrate the prepreg 3 in the thickness direction with an opening dimension substantially equal to the outer dimension of the functional element body 5.

  The prepreg 3 is appropriately formed with vias that are connected to the lands 8 b on the module substrate 2 side by being subjected to a via formation step in a state where the prepreg 3 is bonded to the module substrate 2. The prepreg 3 makes electrical connection between the wiring substrate 4 and the module substrate 2 stacked through each via.

  As shown in FIG. 5, the wiring board 4 has a first wiring pattern 16 and a second wiring pattern 17 formed on a first main surface 4a and a second main surface 4b. In the wiring board 4, the first wiring pattern 16 and the second wiring pattern 17 are appropriately connected through vias (not shown) at appropriate positions. Since the wiring substrate 4 is integrated with the module substrate 2 via the prepreg 3 in a wiring substrate stacking step described later, an organic insulating substrate having the same thermal expansion coefficient as that of the module substrate 2 is used.

  In the wiring substrate 4, the first wiring pattern 16 formed on the first main surface 4 a constituting the laminated surface with respect to the module substrate 2 is connected to the second shield pattern 18 and the first wiring pattern 8 on the module substrate 2 side. It has a terminal part. The second shield pattern 18 is formed over the entire surface in a region facing the entire functional element body mounting region 9. The second shield pattern 18 is in pressure contact with the bottom surface 5 c facing the functional surface 5 a of the functional element body 5.

  In the wiring board 4, the second main surface 4 b constitutes a mounting surface on which electronic components such as an amplifier and a mixer (not shown) or chip components are mounted. In the wiring board 4, the second wiring pattern 17 formed on the second main surface 4b has a mounting land 17a and a ground pattern 17b for connecting mounting parts, or a line pattern for connecting each pattern. By mounting the functional element body 5 in the layer, the wiring board 4 secures a mounting space for components and the like on the second main surface 4b and improves the mounting efficiency. Although the wiring board 4 is shown as a double-sided board, it may be configured by a multilayer wiring board in which wiring layers are formed in multiple layers on the inner layer by the multilayer wiring board technology as in the module board 2 described above. Of course.

  In the circuit module body 1, a functional element body 5 is mounted on a module substrate 2, and a wiring board 4 is laminated on the module substrate 2 through a prepreg 3 to form a ground via, which will be described later. The process is performed, and the first shield pattern 12 and the second shield pattern 18 on the module substrate 2 side are interlayer-connected by the ground via 19. As shown in FIG. 1, the ground via 19 connects the ground pattern 17 b formed on the second wiring pattern 17 of the wiring substrate 4 and the ground pattern 8 a formed on the first wiring pattern 8 of the module substrate 2.

  In the circuit module body 1, the functional element body 5 mounted in the functional element body mounting region 9 of the module substrate 2 includes a first shield pattern 12 formed on the module substrate 2 side and a second shield pattern formed on the wiring substrate 4 side. 18 is sealed to the inner layer. In the circuit module body 1, the functional element body 5 is prevented from mutual electromagnetic influences with the internal line, the circuit unit, and the like by such a configuration, and is generated by blocking from external electromagnetic noise (EMI) or electrostatic charging. The occurrence of sticking of the vibrator 5b or the like is prevented, and a stable operation is performed, thereby improving the reliability. In the circuit module body 1, the first shield pattern 12 and the second shield pattern 18 that cover the functional element body 5 also have a moisture-proof function of the recessed portion 6.

  The circuit module body 1 described above is manufactured through a module board manufacturing process, a functional element body mounting process, a prepreg bonding process, a wiring board bonding process, and an earth via forming process. The module substrate manufacturing process uses a double-sided substrate with copper foil attached to both sides of the organic insulating base material described above, and forms a resist layer on the copper foil and overlays a mask having a predetermined pattern on it. The layer is subjected to a photosensitive process, and the copper foil is subjected to an etching process in a state where unnecessary resist is removed to form a wiring pattern. In the module substrate manufacturing process, after a prepreg is bonded to the surface of the double-sided substrate or an insulating layer is formed, a metal thin film layer is formed by sputtering or the like, and the above-described patterning process is performed on the metal thin film layer.

  In the module substrate manufacturing process, vias for connecting the wiring patterns of the respective layers are also formed, and the first wiring pattern 8 formed on the first main surface 2a and the second wiring pattern 10 formed on the second main surface 2b. Alternatively, the module substrate 2 made of a multilayer wiring substrate having the first shield pattern 12 and the like formed in the inner layer is manufactured. In the module substrate manufacturing process, laser processing or router processing is performed on the first main surface 2a of the module substrate 2 to form the recessed portion 6 having a predetermined opening size and depth. In the module substrate manufacturing process, a part of the first shield pattern 12 formed in the inner layer is exposed at the bottom of the recessed portion 6. In the module substrate manufacturing process, via formation for appropriately connecting the wiring patterns of the respective layers to each other is performed.

  In the module substrate manufacturing process, the inexpensive module substrate 2 is efficiently manufactured by the multilayer wiring substrate technology using relatively inexpensive materials and simple equipment. The module substrate manufacturing process is not limited to the above-described process, and the module substrate 2 may be manufactured by an appropriate multilayer wiring board technique that has been conventionally performed. In the module substrate manufacturing process, for example, an uppermost prepreg is bonded onto the formation layer of the first shield pattern 12, and an opening that forms the recessed portion 6 is formed in advance in the prepreg by laser processing or a mold. It may be.

  In the functional element body mounting process, the functional element body 5 is mounted on the functional element body mounting region 9 of the mounting surface and the first main surface 2a with respect to the first main surface 2a of the module substrate 2. In the functional element body mounting process, the functional element body 5 forms bumps 14 on the respective input / output electrodes 13 as shown in FIG. And are combined on the functional element body mounting area 9. In the functional element body mounting step, the functional element body 5 covers the recessed portion 6 so that the vibrator 5b faces the internal space and is held at a predetermined facing distance from the first shield pattern 12.

  In the functional element body mounting step, for example, the functional element body mounting electrodes 7 opposed to the input / output electrodes 13 are bumped 14 by performing a heating / pressing operation of the functional element body 5 on the module substrate 2 with a heating and pressing device. Connect electrically and mechanically. In the functional element body mounting step, it is possible to perform strong bonding at a low temperature by using, for example, an operation of applying ultrasonic waves to the bonding sites. In the functional element body mounting step, an underfill filling step of filling a liquid epoxy resin material containing filler, for example, with a dispenser may be performed on the joint portion as necessary.

  In the functional element body mounting step, the method is not limited to the method of joining the input / output electrode 13 and the functional element body mounting electrode 7 by the above-described gold crimping method. In the functional element body mounting step, for example, solder bumps are formed on each input / output electrode 13 by a printing method or the like, and the functional element body 5 is placed on the module substrate 2 and subjected to reflow soldering processing. The body 5 may be flip-chip mounted.

  In the prepreg joining step, as shown in FIG. 7, the module substrate 2 is formed by fitting the semi-cured prepreg 3 formed with the opening 15 corresponding to the functional element body 5 into the opening 15. The first main surface 2a is laminated. In the prepreg joining step, by using the prepreg 3 having a thickness substantially equal to the thickness of the functional element body 5, the functional element body 5 accommodates the bottom surface 5 c so as to constitute substantially the same surface as the opening surface of the opening 15.

  In the wiring board manufacturing process, for example, a double-sided board having an organic insulating substrate as a base material and copper foil attached to both sides is used, and the wiring board 4 is manufactured by a general wiring board technique. In the wiring board manufacturing process, a resist layer is formed on the copper foil of the double-sided board and a mask having an opening with a predetermined pattern is superimposed to perform a photosensitive treatment of the resist layer, and the unnecessary resist is removed to form a copper foil. By performing the etching process, the first wiring pattern 16 having the second shield pattern 18 is formed on the first main surface 4a, and the wiring substrate 4 having the second wiring pattern 17 formed on the second main surface 4b is manufactured.

  In the wiring board manufacturing process, the first wiring pattern 16 having terminal portions connected to the second shield pattern 18 and the first wiring pattern 8 on the module board 2 side is formed on the first main surface 4a. In the wiring board manufacturing process, the second wiring pattern 17 having a mounting land 17a, a ground pattern 17b, or a line pattern connecting each pattern is formed on the second main surface 4b. In the wiring board manufacturing process, a via for appropriately connecting the first wiring pattern 16 and the second wiring pattern 17 is formed.

  In the wiring board manufacturing process, as described above, an organic insulating substrate having the same thermal expansion coefficient as that of the module substrate 2 is used as a base material. However, the present invention is not limited to such an organic insulating substrate. In the wiring board manufacturing process, it is preferable to manufacture the wiring board 4 using a base material that has no significant difference in coefficient of thermal expansion from the module board 2. Further, in the wiring board manufacturing process, it is needless to say that the wiring board 4 may be manufactured using a multilayer wiring board in the same manner as the module board 2 described above.

  In the wiring board bonding step, as shown in FIG. 8, the wiring board 4 is laminated on the prepreg 3, the opening 15 is closed and combined, and the prepreg 3 is cured by applying a heat pressing process, so that the wiring board 4 is modularized. Integrate with the substrate 2. In the wiring board bonding step, the wiring board 4 is laminated on the prepreg 3 with the first main surface 4a as a mounting surface. In the wiring board bonding step, the prepreg 3 pressed through the wiring board 4 enters the non-formation portion of the first wiring pattern 8 on the first main surface 2a of the module board 2, and the first side on the wiring board 4 side. Even on the first main surface 4a, the first wiring pattern 16 is not formed. In the wiring board bonding step, the second shield pattern 18 formed on the first main surface 4 a of the wiring board 4 is in close contact with the bottom surface 5 c of the functional element body 5.

  In the wiring board bonding step, the heated prepreg 3 is bonded to the module board 2 and the wiring board 4 by curing the impregnated thermosetting adhesive resin, whereby the module board 2 and the wiring board 4 are bonded. Are integrated to form a laminated wiring board body 20 shown in FIG. The laminated wiring board body 20 holds the functional element body 5 firmly in the layer when the prepreg 3 is in close contact with the outer peripheral portion of the functional element body 5 excluding the functional surface 5a. In the layered wiring board body 20, the functional element body 5 encloses the vibrator 5b provided on the functional surface 5a so as to be able to perform a vibration operation by facing the recessed portion 6 in the layer. In the multilayer wiring board body 20, the functional element body 5 shields the functional surface 5 a by the first shield pattern 12 of the module substrate 2 and shields the bottom surface 5 c by the second shield pattern 18 of the wiring substrate 4.

  In the ground via formation step, the ground via 19 that connects the first shield pattern 12 and the second shield pattern 18 is formed in the multilayer wiring board body 20. As shown in FIG. 9, the ground via forming step penetrates the prepreg 3 from the ground pattern 17 b of the second wiring pattern 17 formed on the second main surface 4 b of the wiring substrate 4, and the first wiring layer 8 of the module substrate 2. A via hole 21 reaching the ground pattern 8a formed in (1) is formed. In the earth via formation step, the via hole 21 is formed by, for example, laser irradiation, plasma irradiation, or so-called dry etching processing or drill processing in which these are simultaneously irradiated.

  In the ground via formation step, the via hole 21 is subjected to, for example, through-hole plating by copper plating to form the ground via 19 that conducts the ground pattern 8a and the ground pattern 17b. In the ground via forming step, as described above, the module substrate 2 is connected to the ground pattern 8a of the first wiring pattern 8 and the first shield pattern 12 through the via 11 in the layer, and the ground pattern is formed on the wiring substrate 4 as well. 17b is connected to the second shield pattern 18 through a via, thereby forming an earth 19 for connecting the first shield pattern 12 and the second shield pattern 18.

  In the earth via forming step, for example, a metal plating layer may be formed in the via hole 21 and then filled with a resin material, and the lid of the resin layer may be closed by metal plating. The earth via 19 may be formed by an appropriate via forming method implemented in the wiring board technology. In the earth via forming step, the via formation is performed after the wiring substrate 4 is joined. For example, after the prepreg 3 is laminated, the via is formed simultaneously with the formation of the via for connecting the wiring pattern applied to the prepreg 3. Of course, it is also good.

It is sectional drawing of the circuit module body shown as embodiment. It is sectional drawing of a module board | substrate. It is a side view of a functional element body. It is sectional drawing of a prepreg. It is sectional drawing of a wiring board. It is sectional drawing which shows the mounting process of the functional element body with respect to a module board. It is sectional drawing which shows the lamination process of a prepreg. It is sectional drawing which shows the joining process of a wiring board. It is sectional drawing of the laminated wiring board body in which the via hole was formed. It is a block diagram of a low IF system RF circuit module. It is a block diagram of a direct conversion RF circuit module.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circuit module body 2 Module board 3 Prepreg 4 Wiring board 5 Functional element body 6 Recessed part 7 Functional element body mounting electrode 8 First wiring pattern 9 Functional element body mounting area 10 Second wiring Pattern, 11 Via, 12 First shield pattern, 13 Input / output electrode, 14 Bump, 15 Opening, 16 First wiring pattern, 17 Second wiring pattern, 18 Second shield pattern, 19 Earth via, 20 Multilayer wiring board body, 21 Beer Hall

Claims (4)

The wiring pattern is formed in multiple layers via the insulating layer, and the first main surface has a recessed portion that exposes the first shield pattern formed in the inner layer at the bottom, and a large number arranged in a region surrounding the recessed portion. A multilayer wiring board on which a wiring pattern having a plurality of element mounting electrodes is formed;
The multilayer wiring board is combined on the first main surface of the multilayer wiring board so that the concave portion is covered with the functional surface as a mounting surface, and the input / output electrodes are connected to the opposing element mounting electrodes. Functional element body mounted on
An opening having a thickness substantially equal to the thickness of the functional element body and substantially the same as the outer shape of the functional element body is formed, and the functional element body is accommodated in the opening so as to accommodate the multilayer wiring board. A prepreg joined to the first main surface;
A second shield pattern is formed at a portion facing the functional element body, the opening is closed, and the functional element body is sealed by being combined on the prepreg, and the multilayer wiring board is interposed through the prepreg. It is composed of an integrated wiring board,
The functional element body is sealed in an inner layer between a first shield pattern of the multilayer wiring board and a second shield pattern of the wiring board which are interlayer-connected by an earth via formed through the prepreg. Circuit module body to be used.   2. The circuit module body according to claim 1, wherein the functional element body is a surface acoustic wave filter element or a bulk acoustic wave filter element having a vibrator on a functional surface.   The circuit module body according to claim 1, wherein the first wiring board and the second wiring board are formed using an organic insulating substrate as a base material. A wiring pattern is formed in multiple layers through an insulating layer using an organic insulating substrate as a base material, and a concave portion exposing the first shield pattern formed in the inner layer at the bottom is formed on the first main surface, and the concave portion A multilayer wiring board manufacturing process for manufacturing a multilayer wiring board on which a wiring pattern having a plurality of element mounting electrodes arranged in a surrounding region is formed;
The functional element body is mounted on the first main surface of the multilayer wiring board by combining the functional surface as a mounting surface so as to cover the concave portion and connecting the input / output electrodes to the opposing element mounting electrodes. A functional element assembly mounting process,
A prepreg laminating step of laminating a prepreg having an opening substantially equal to the outer shape of the functional element body on the first main surface of the multilayer wiring board so as to accommodate the functional element body in the opening;
Forming a first wiring pattern having a second shield pattern on a first main surface using an organic insulating substrate as a base material, and manufacturing a wiring substrate having a second wiring pattern formed on a second main surface;
The wiring board is combined with the first main surface as a mounting surface, the second shield pattern facing the functional element body accommodated in the opening portion, the opening portion being closed on the prepreg, and heating. A wiring board bonding step for integrating with the multilayer wiring board via the prepreg that is cured by being subjected to a pressing treatment;
An earth via forming step for forming an earth via for interlayer connection between the first shield pattern of the multilayer wiring board and the second shield pattern of the wiring board;
A method of manufacturing a circuit module body, wherein a circuit module body in which the functional element body is sealed in an inner layer between the first shield pattern and the second shield pattern is manufactured.

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