JP2005223225A - Composite multilayer substrate, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, although the exemplary composite multilayer substrate used in a conventional high-frequency semiconductor device is so constituted as to join the rear surface of a ceramic substrate to the composite resin material layer comprising an epoxy resin and an inorganic filler, since the ceramic substrate and the composite resin material layer are joined to each other via a resin material, the force whereby the ceramic substrate and the composite resin material layer are joined to each other has been so weak that the ceramic substrate and the composite resin material layer are stripped from each other by such an external force as the impact force generated when dropping them. <P>SOLUTION: A composite multilayer substrate 1 so has a ceramic multilayer substrate 2 and so has a resin layer 3 as to join the ceramic multilayer substrate 2 to the resin layer 3. The ceramic multilayer substrate 2 so has a circuit pattern 4 and the resin layer 3 so has via-hole conductors 6 and so has external terminal electrodes 7 that the circuit pattern 4 and the external terminal electrodes 7 are connected by the via-hole conductors 6. A junction reinforcing member 8 for reinforcing the force whereby the ceramic multilayer substrate 2 and the resin layer 3 are joined to each other is provided along the direction of both 2, 3 being laminated therein. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a composite multilayer substrate having a ceramic substrate and a resin layer, and a method for manufacturing the same, and more particularly to a highly reliable composite multilayer substrate that does not peel between the ceramic substrate and the resin layer and a method for manufacturing the same. .

  As a conventional composite multilayer substrate, for example, a composite multilayer substrate used in a high-frequency semiconductor device described in Patent Document 1 is known. In this high-frequency semiconductor device, a composite resin material layer made of an epoxy resin and an inorganic filler formed on the lower surface of a ceramic substrate is formed, and the lower portion of the composite resin material layer has a flat shape and is used for an external connection terminal Electrodes are formed inside the composite resin material layer, embedded with semiconductor elements and passive components connected to a ceramic substrate, and as a module package with an all-in-one structure for transmission and reception, miniaturization and high-density mounting Realized.

  As described above, the composite multilayer substrate used in the high-frequency semiconductor device includes a ceramic substrate and a composite resin material layer formed on the lower surface of the ceramic substrate, and the composite resin material layer is formed on the lower surface of the ceramic substrate. It is joined to.

JP 2003-124435 A

  However, the composite multilayer substrate used in the high-frequency semiconductor device described in Patent Document 1 is configured by bonding a composite resin material layer made of an epoxy resin and an inorganic filler to the lower surface of the ceramic substrate. And the composite resin material layer are bonded via the resin material, so the adhesion between the ceramic substrate and the composite resin material layer is inferior, and the bonding force between the two is weak, so external forces such as impact force when falling When acting on the composite multilayer substrate, there is a possibility that the ceramic substrate and the composite resin material layer are peeled off, and there is a problem that the reliability is poor.

  When the ceramic multilayer substrate and the resin layer are joined, the conductor multilayer 1 of the ceramic multilayer substrate 1 and the conductive resin layer 2A of the resin layer 2 are aligned as shown in FIG. The resin layer 2 is joined to the conductive layer 2A. If there is a poorly filled portion 2C of the conductive resin in a part of the conductive resin layer 2A, the conductor pattern 1A can be obtained even if the resin layer 2 is joined to the ceramic multilayer substrate 1. There is a problem that poor connection occurs between the conductive resin layer 2 having the poorly filled portion 2C and the conductor pattern 1A. Even if the conductive resin layer 2A is not filled poorly, if there are irregularities such as undulations 1B on a part of the joint surface of the ceramic multilayer substrate 1 as shown in FIG. 10, the conductive pattern 1A and the conductive resin layer are also formed. There was a problem that poor connection with 2A occurred.

  The present invention has been made to solve the above problems, and has a strong bonding force between the ceramic substrate and the resin layer, and prevents peeling between the ceramic layer and the resin layer even when an external force such as an impact force is applied. It is an object of the present invention to provide a highly reliable composite multilayer substrate and a method for manufacturing the same. It is another object of the present invention to provide a composite multilayer substrate and a method of manufacturing the same that can electrically connect both of the ceramic substrate and the resin layer, even if there are some defects.

  A composite multilayer substrate according to claim 1 of the present invention is a ceramic substrate having a first main surface and a second main surface opposite to the first main surface, and a first main surface and a second main surface opposite to the first main surface. And a second main surface of the ceramic substrate and the first main surface of the resin layer are bonded to each other, the ceramic substrate has a circuit pattern, and the resin layer includes a via-hole conductor and a second hole. A composite multi-layer substrate having an external terminal electrode formed on the main surface of the substrate, wherein the circuit pattern and the external terminal electrode are connected via the via-hole conductor, and bonding the ceramic substrate and the resin layer At least one joint reinforcing member that reinforces the force is provided in the stacking direction of both of them.

  The composite multilayer substrate according to claim 2 of the present invention is the composite multilayer substrate according to claim 1, wherein the ceramic substrate is formed of a ceramic multilayer substrate formed by laminating a plurality of ceramic layers. It is what.

  The composite multilayer substrate according to claim 3 of the present invention is characterized in that, in the invention according to claim 1 or 2, the joining reinforcing member bites into the resin layer side from the ceramic substrate. It is what.

  According to a fourth aspect of the present invention, in the composite multilayer substrate according to any one of the first to third aspects, the joining reinforcing member is electrically connected to a circuit pattern of the ceramic substrate. It is characterized by being independent.

  Moreover, the composite multilayer substrate according to claim 5 of the present invention is the invention according to any one of claims 1 to 3, wherein the bonding reinforcing member is a via-hole conductor provided on the ceramic substrate. It is characterized by being formed.

  According to a sixth aspect of the present invention, there is provided the composite multilayer substrate according to the fifth aspect, wherein the joint reinforcing member constitutes a part of a circuit pattern of the ceramic substrate. is there.

  A composite multilayer substrate according to claim 7 of the present invention is characterized in that, in the invention according to claim 5 or 6, it is bitten into the via-hole conductor of the resin layer.

  Moreover, the composite multilayer substrate according to claim 8 of the present invention is the invention according to any one of claims 5 to 7, wherein the cross-section of the via-hole conductor of the resin layer is the via-hole conductor of the ceramic substrate. It is characterized in that it is formed to be larger than the cross section.

  According to a ninth aspect of the present invention, there is provided the composite multilayer substrate according to any one of the first to eighth aspects, wherein the front end of the joint reinforcing member is the first and second ends of the resin layer. It is characterized by being located 5 μm or more from each of the two main surfaces.

Moreover, the composite multilayer substrate according to claim 10 of the present invention is the invention according to any one of claims 1 to 9, wherein the cross-sectional area of the joint reinforcing member is 0.01 to 0.9 mm. It is characterized by being ^two .

  Further, in the composite multilayer substrate according to claim 11 of the present invention, in the invention according to any one of claims 1 to 10, the external terminal electrode is formed of a metal foil. It is what.

  The composite multilayer substrate according to claim 12 of the present invention is the composite multilayer substrate according to any one of claims 2 to 11, wherein the ceramic multilayer substrate contains Ag or Cu as a main component. It has a circuit pattern.

  According to a thirteenth aspect of the present invention, there is provided the composite multilayer substrate according to any one of the first to twelfth aspects, wherein the resin layer contains a chip component. It is.

  According to a fourteenth aspect of the present invention, there is provided a method for producing a composite multilayer substrate comprising: a step of providing at least one through hole in a resin sheet; a step of filling an inorganic paste in the through hole of the resin sheet; Integrating the resin sheet filled with the paste and the ceramic green sheet, firing the ceramic green sheet and the resin sheet to obtain a ceramic substrate and a joining reinforcing member protruding from the ceramic substrate, and the ceramic And a step of bonding the substrate and the resin layer having the external terminal electrode via the bonding reinforcing member.

  According to a fifteenth aspect of the present invention, there is provided a method for producing a composite multilayer substrate according to the fourteenth aspect, wherein a conductive paste is used as the inorganic paste.

  According to claim 16 of the present invention, in the method for manufacturing a composite multilayer substrate according to claim 14, in the step of providing at least one through hole in the resin sheet, a plurality of the through holes are provided, and It is characterized in that at least a part thereof is provided corresponding to the conductive resin layer formed on the resin layer.

  According to a seventeenth aspect of the present invention, in the method for manufacturing a composite multilayer substrate according to the sixteenth aspect, the cross-sectional area of the through hole is formed smaller than the cross-sectional area of the conductive resin layer. It is a feature.

  According to the first to seventeenth aspects of the present invention, the bonding force between the ceramic substrate and the resin layer is strong, and even when an external force such as an impact force is applied, the separation between the ceramic layer and the resin layer is performed. It is possible to provide a highly reliable composite multilayer substrate and a method for manufacturing the same. Also, it is possible to provide a composite multilayer substrate and a method for manufacturing the same that can electrically connect both of the ceramic substrate and the resin layer to each other even if there are some defects.

  Hereinafter, the present invention will be described based on the embodiment shown in FIGS. 1 is a sectional view showing an embodiment of the composite multilayer substrate of the present invention, FIG. 2 is a sectional view showing another embodiment of the composite multilayer substrate of the present invention, and FIGS. FIG. 6 to FIG. 8 are cross-sectional views showing the manufacturing process of the composite multilayer substrate shown in FIG. 2, respectively.

  For example, as shown in FIG. 1, the composite multilayer substrate 1 of the present embodiment has a first main surface (upper surface) and a second main surface (lower surface) opposite to the first main surface (multiple ceramic layers 2A). And a resin layer 3 having a first main surface (upper surface) and a second main surface (lower surface) opposite to the first main surface (upper surface). The lower surface and the upper surface of the resin layer 3 are firmly bonded. The composite multilayer substrate 1 of the present embodiment is manufactured by firing a ceramic green sheet laminate to prepare a ceramic multilayer substrate 2 and then bonding the resin layer 2 to the lower surface of the ceramic multilayer substrate 2 as described later. can do. The composite multilayer substrate 1 is used as a mounting component that is electrically connected to a ground electrode (not shown) of a mother board such as a printed wiring board by soldering, for example.

  The ceramic multilayer substrate 2 has a circuit pattern 4 as shown in FIG. The circuit pattern 4 includes a conductor pattern 4A formed on the upper surface of each ceramic layer 2A using a printing technique such as screen printing, and via-hole conductors 4B that connect the upper and lower conductor patterns 4A and 4A to each other. . The circuit pattern 4 is formed of a metal sintered body obtained by co-firing a conductive paste with a ceramic green sheet. Further, an electrode 5 formed by the same method as that of the conductor pattern 4A is interposed at the interface between the ceramic multilayer substrate 2 and the resin layer 3, and this electrode 5 is formed integrally with the lowermost ceramic layer 2A.

  As will be described later, the electrode 5 is preferably formed in a range that occupies 3 to 80% of the area of the lower surface of the ceramic multilayer substrate 2 by, for example, a sintered metal. The ceramic multilayer substrate 2 is usually formed of glass ceramics, and since the glass ceramics has a surface roughness Rmax (several μm) comparable to that of the copper foil, the bonding force with the resin layer 3 is weak. Therefore, in the present embodiment, the electrode 5 is interposed between the ceramic multilayer substrate 2 and the resin layer 3, and the sintered metal has a surface roughness Rmax of several tens of μm, which is smaller than the surface roughness of the copper foil of several μm. Since the order of magnitude is higher, the bonding strength with the resin layer 3 can be increased by the anchor effect of the sintered metal. The difference in surface roughness is that the copper foil is formed by plating or rolling a copper plate, whereas the sintered metal contains a conductive paste containing 10 to 40% by volume of a resin called varnish. Since it is formed by baking, the resin component is burned away, leaving voids inside and on the surface and increasing the surface roughness. The electrode 5 may be formed as a part of the circuit pattern 4 of the ceramic multilayer substrate 2, or may be formed as a dummy electrode independent of the circuit pattern 4.

  The electrode 5 can be formed as a ground electrode. By providing a ground electrode at the interface between the ceramic multilayer substrate 2 and the resin layer 3, it is possible to electrically shield between the ceramic multilayer substrate 2 and a mother board (not shown) such as a printed wiring board. Further, by configuring the electrode 5 as the ground electrode of the ceramic multilayer substrate 2, the connection distance to the ground electrode of the motherboard can be shortened, and the parasitic inductance value can be reduced. Good high frequency characteristics can be obtained when used as a high frequency component. The electrode 5 is ideally formed on the lower surface of the resin layer 3. However, when other wiring is arranged on the mother board side in high-density mounting, a measurement hole after mounting (probe insertion) May be vacant, and it is difficult to provide substantially on the lower surface of the resin layer 3, so that it is interposed at the interface between the ceramic multilayer substrate 2 and the resin layer 3.

  As shown in FIG. 1, the resin layer 3 has a via-hole conductor 6 connected to the circuit pattern 4 of the ceramic multilayer substrate 2 and an external terminal electrode 7 formed on the lower surface. The circuit pattern 4 of the multilayer substrate 2 is electrically connected via the via-hole conductor 6. Unlike the via hole conductor 5 of the ceramic multilayer substrate 2, the via hole conductor 6 is formed of a conductive resin containing conductive metal powder. Therefore, as shown in FIG. 1, by forming the via-hole conductor 6 to have a larger cross-sectional area than the via-hole conductor 4B of the ceramic multilayer substrate 2, the resistance of the via-hole conductor 4B is brought close to and the reliability of the junction with the via-hole conductor 4B is increased. Increases sex. The external terminal electrode 7 is preferably formed of a metal foil such as a copper foil. By using a metal foil as the external terminal electrode 7, the external terminal electrode 7 can be formed with low resistance and low cost. The external terminal electrode 7 is not a thick film electrode but a copper foil because it is on the resin layer 3 side and cannot be fired, and a combination of copper foil and resin can be used to produce a printed wiring board. It is.

  By the way, in this embodiment, the adhesion strength between the ceramic multilayer substrate 2 and the resin layer 3 is increased by the electrode 5 made of sintered metal. When a strong external force such as an impact force is applied, there is a possibility that the two and 3 are separated. Therefore, in the present embodiment, as shown in FIG. 1, at least one bonding reinforcing member 8 for reinforcing the bonding force between the ceramic multilayer substrate 2 and the resin layer 3 is provided in the stacking direction of the two and three. It has been. If at least one bonding reinforcing member 8 is provided, the bonding force between the ceramic multilayer substrate 2 and the resin layer 3 can be increased. In this embodiment, the bonding reinforcing member 8 is provided at a plurality of locations to further strengthen the bonding force.

  The joint reinforcing member 8 is formed of, for example, a sintered metal co-fired with the ceramic multilayer substrate 2 in the same manner as the via-hole conductor 4B, and is pierced into the resin layer 3 from the ceramic multilayer substrate 2. The tip of the joint reinforcing member 8 may be pointed or swelled. When it is sharp, it is easy to pierce the resin layer 3, and when it is swollen, it is difficult to come out of the resin layer 3.

It is preferable that the tip of the joint reinforcing member 8 is pierced into the resin layer 3 to a depth of 5 μm or more, and is further pierced from the non-joint surface of the resin sheet 13, that is, at a depth that leaves a remaining margin of 5 μm or more. If the depth is less than 5 μm, the effect of the present invention is not substantially obtained, and if the remaining allowance is less than 5 μm, the joining reinforcing member 8 may be exposed to the outside due to an unexpected cause. The cross-sectional area of the bonding reinforcing member 8 is preferably in the range of 0.01 to 0.90 mm ² . If the cross-sectional area is less than 0.01 mm ^{2, the} cross-sectional area may be too thin and breakage may occur. If the cross-sectional area exceeds 0.90 mm ² , the via paste layer may not be substantially filled.

  As shown in FIG. 1, the joint reinforcement member 8 includes a first joint reinforcement member 8 </ b> A constituting a part of the circuit pattern 4 and a second joint reinforcement formed electrically independent from the circuit pattern 4. It consists of two types of members 8B. The first and second bonding reinforcing members 8A and 8B are preferably arranged so as to form a surface rather than those arranged on the lower surface of the ceramic multilayer substrate 2 in a straight line. In the present embodiment, the joint reinforcing member 8 is composed of the first and second joint reinforcing members 8A and 8B, but the second joint reinforcing member 8B formed electrically independent of the circuit pattern 4 is used. Needless to say, it may be configured only from the above. The first and second bonding reinforcing members 8A and 8B are both pierced into the resin layer 3.

Thus, in the present embodiment, the ceramic multilayer substrate 2 is preferably formed of, for example, a low-temperature sintered ceramic material. A low-temperature sintered ceramic material refers to a ceramic material that can be fired at a temperature of 1000 ° C. or lower. Examples of the low-temperature sintered ceramic material include ceramic powders such as alumina, forsterite, and cordierite, glass composite materials obtained by mixing borosilicate glass with these ceramic powders, and ZnO-MgO-Al ₂ O ₃ -SiO _2. Crystallized glass-based material using BaO-based crystallized glass, BaO—Al ₂ O ₃ —SiO ₂ ceramic powder, Al ₂ O ₃ —CaO—SiO ₂ —MgO—B ₂ O ₃ ceramic powder, etc. Non-glass-based materials can be exemplified. By using a low temperature sintered ceramic material for the ceramic multilayer substrate 2, a low melting point metal having a low resistance and a low melting point such as Ag or Cu can be used for the circuit pattern 4. Co-firing can be performed at a low temperature of ℃ or less.

  FIG. 2 shows another embodiment of the composite multilayer substrate of the present invention. The composite multilayer substrate of the present embodiment is configured in the same manner as in the above embodiment except that the arrangement form of the bonding reinforcing member is different. Therefore, the same reference numerals are given to the same or corresponding parts as in the above embodiment. The features of the embodiment will be described.

  The joint reinforcing member 8 in the present embodiment is composed of two types of first and second joint reinforcing members 8A and 8B as in the composite multilayer substrate 1 shown in FIG. The first bonding reinforcing member 8A also serves as the via-hole conductor 4B of the ceramic multilayer substrate 2 and penetrates the via-hole conductor 6 of the resin layer 3 so as to have the same potential as the external terminal electrode 7. Further, since the via-hole conductor 6 is formed of a conductive resin layer containing metal powder, the first bonding reinforcing member 8A is more firmly connected to the via-hole conductor 6 than when the first bonding reinforcing member 8A is pierced into the resin layer 3. ing.

The first joint reinforcing member 8A preferably has a cross-sectional area larger than 0.01 mm ^{2 and an} area of 90% or less of the cross-sectional area of the via-hole conductor 6 on the resin layer 3 side. If the cross-sectional area of the first bonding reinforcing member 8A is less than 0.01, there is a risk of breakage. If it exceeds 90% of the cross-sectional area of the via-hole conductor 6 on the resin layer 3 side, it is difficult to pierce the via-hole conductor 6. It is not preferable. The second joint reinforcing member 8B is directly pierced into the resin layer 3 as in the case shown in FIG. 1, and the cross-sectional area thereof is the same as that of the first joint reinforcing member 8A. The first and second joint reinforcing members 8A and 8B may have different cross-sectional areas.

  Although not shown in FIGS. 1 and 2, when active chip components such as semiconductor elements and passive chip components such as capacitors and inductors are mounted on the circuit pattern on the lower surface of the ceramic multilayer substrate 2. The resin layer 3 has a function of embedding and sealing these chip components.

  Next, the manufacturing method of the composite multilayer board | substrate of this invention is demonstrated concretely based on the following Example. The method of the present invention is characterized in that the ceramic multilayer substrate 2 and the joint reinforcing member 8 are formed simultaneously.

In this embodiment, the composite multilayer substrate shown in FIG. 1 is manufactured by the following procedure.
(1) Preparation of Ceramic Green Sheet and Resin Sheet In this example, 55 parts by weight of alumina particles having a center particle diameter of 1.0 μm and 45 parts by weight of borosilicate glass having a center particle diameter of 1.0 μm and a softening point of 600 ° C. The mixture was dispersed in a vinyl alcohol binder to prepare a slurry, and this slurry was applied on a carrier film made of a polyethylene terephthalate resin. As shown in FIG. A ceramic green sheet 12A for low-temperature sintering of 50 μm was produced. Separately, after preparing a slurry by dispersing polypropylene powder in a vinyl alcohol binder, this slurry was applied on a carrier film made of polyethylene terephthalate resin, and a resin sheet having a thickness of 30 μm as shown in FIG. 20 was produced. The ceramic green sheet 12A and the resin sheet 20 were formed having the same area.

Next, through holes (via holes) were formed in each of the ceramic green sheets 12A and the resin sheet 20 by mechanical punching using a mold or thermal punching using light rays, and arranged in a predetermined pattern. At this time, the ceramic green sheet 12 </ b> A corresponding to the lowermost ceramic layer 2 </ b> A of the ceramic multilayer substrate 2 is a first joint that also serves as a via hole for the via hole conductor 4 </ b> B constituting the circuit pattern 4 and a via hole conductor constituting the circuit pattern 4. A via hole for the reinforcing member 8A and a via hole for the second bonding reinforcing member 8B were formed. In addition, via holes were formed in the resin sheet 20 in the same pattern as the first and second bonding reinforcing members 8A and 8B. The via holes corresponding to the first and second joint reinforcing members 8A and 8B both have a cross-sectional area in the range of 0.01 to 0.90 mm ² .

  Thereafter, a conductive paste containing Ag powder or Cu powder is used in a state in which a ceramic green sheet 12A having via hole conductor holes formed at predetermined locations by laser processing or punching is in close contact with a smooth support base. Using a squeegee from the film side, it is pushed into the via hole conductor hole in the ceramic green sheet 12A, and at the same time, the excess conductive paste is scraped to remove the via paste layer 14B for the via hole conductor and the first and second joint reinforcing members. Via paste layers 18A and 18B (see FIG. 3) were formed. At this time, the conductive paste can be surely filled into the via hole by attaching a suction mechanism to the support base and making the via hole have a negative pressure. In addition, dirt on the ceramic green sheet 12A can be prevented by sandwiching a breathable film between the support base and the ceramic green sheet 12A. Similarly, the conductive paste was filled in the via holes of the resin sheet 20 to form via paste layers 18A and 18B (see FIG. 3) for the first and second bonding reinforcing members.

  Then, as shown in FIG. 3, a conductive paste layer 14 </ b> A that becomes a conductive pattern 4 </ b> A such as an in-plane wiring or an electrode was formed by screen printing a conductive paste on each ceramic green sheet 12 </ b> A. A conductive paste layer 15 for the electrode 5 of the ceramic multilayer substrate 2 was formed on the resin sheet 20.

(2) Production of Raw Ceramic Laminate First, the ceramic green sheet 12A forming the uppermost ceramic layer 2A shown in FIG. 1 is mounted on a fixing jig with the carrier film removed. As the fixing jig, a frame-shaped mold having substantially the same size as the ceramic green sheet 12A, a pin-shaped jig that passes through a fixing through-hole formed in the ceramic green sheet 12A in advance, or the like can be used. Next, the ceramic green sheet 12A to be laminated is laminated on the ceramic green sheet 12A previously placed with the carrier film removed. At this time, the ceramic green sheets 12A and 12A may be pressure-bonded by applying a predetermined pressure. Thereafter, the ceramic green sheets 12A were sequentially laminated in a predetermined order, and finally the lowermost ceramic green sheet 12A was laminated to obtain a laminate 12 of the ceramic green sheets 12A shown in FIG. Further, after laminating the resin sheet 20 on the laminate 12 as shown in FIG. 3, a predetermined pressure is applied from the upper surface of the resin sheet 20 to press the laminate of the ceramic green sheet 12A and the resin sheet 20, A raw ceramic laminate in which the laminate 12 of the ceramic green sheet 12A and the resin sheet 20 were integrated was produced.

(3) Production of Ceramic Multilayer Substrate After a cut line is formed on the raw ceramic laminate for dividing it into product-sized sub-substrates after firing, the raw ceramic laminate is fired at 920 ° C. During firing, the organic components and the resin sheet 20 in the ceramic green sheet 12A are burned away, and the ceramic multilayer substrate 2 and the circuit pattern 4 are sintered. At this time, as shown in FIG. 4, the via paste layers 18A and 18B of the resin sheet 20 become the first and second joining reinforcing members 8A and 8B protruding from the ceramic multilayer substrate 2 by a height of 15 to 25 μm, and the conductor paste The layer 15 becomes an electrode 5 such as a ground electrode of the ceramic multilayer substrate 2. The first and second joint reinforcing members 8A and 8B are dense sintered metal like the circuit pattern 4 in the ceramic multilayer substrate 2 and have a strong structure coupled to the ceramic multilayer substrate 2. Moreover, since the electrode 5 is formed of a sintered metal, it is roughened as compared with a metal foil or the like. Moreover, the ceramic multilayer substrate 2 is completed by performing surface treatment such as plating as necessary.

(4) Preparation of resin layer for composite multilayer substrate A metal foil having a thickness of about 10 to 40 μm is pasted on a support, a photoresist is applied to the surface of the metal foil, and light is irradiated through a photomask. The photoresist is developed to remove unnecessary portions and expose the metal foil. Next, after removing the exposed portion of the metal foil by etching, the photoresist film was peeled off to form the external terminal electrode 7 having a predetermined shape. Thereafter, a thermosetting resin such as an epoxy resin, a phenol resin, or a cyanate resin is mixed with an inorganic fillate such as Al ₂ O ₃ , SiO ₂ , or TiO ₂ , and this mixed resin is laminated on the electrode (heating and pressing). The resin sheet 13 shown in FIG. 5 was produced. A via hole is formed in the resin sheet 13 by irradiating a light beam such as a laser from the side of the resin sheet 13 where the external terminal electrode 7 is not provided. In general, this type of light is easily absorbed by the resin and reflected by the metal, so that a via hole can be formed through only the resin sheet 13 without making a hole in the external terminal electrode 7. Then, the via hole conductor 6 of the resin layer 2 of the composite multilayer substrate 1 was formed by filling the via hole with a conductive resin. As the conductive resin for forming the via-hole conductor 6, for example, a resin made of a mixture of metal particles such as Au, Ag, Cu, and Ni and the same thermosetting resin as the resin sheet 13 was used.

(5) Production of Composite Multilayer Substrate After the resin sheet 13 was peeled from the support, the resin sheet 13 was laminated to the ceramic multilayer substrate 2 as shown in FIG. At this time, the support may be peeled after laminating the resin sheet 13 on the ceramic multilayer substrate 2. When the resin sheet 13 is laminated on the ceramic multilayer substrate 2, the protrusions of the first and second joining reinforcing members 18 </ b> A and 18 </ b> B of the ceramic multilayer substrate 2 are pierced into the resin sheet 13. The protrusions dig into the resin sheet 13 at a depth of 5 μm or more, and are pierced from the non-joint surface of the resin sheet 13 inside, that is, with a remaining margin of 5 μm or more. Sectional area of the bonding reinforcing member 8 is in the range of 0.01mm ² ~0.90mm ^2. After laminating the resin sheet 13 on the ceramic multilayer substrate 2, the resin sheet 13 was thermally cured and integrated with the ceramic multilayer substrate 2 as the resin layer 3 to obtain the composite multilayer substrate 1 shown in FIG. 1.

  As described above, according to the present embodiment, the resin sheet 20 is provided with a plurality of via holes, and after filling the via holes with the conductive paste, the resin sheet 20 and the laminated body 12 of the ceramic green sheets 12A are pressure bonded. And then laminating the laminate 12 to obtain the ceramic multilayer substrate 2 and the first and second joint reinforcing members 8A and 8B at the same time, and then the resin layer having the ceramic multilayer substrate 2 and the external terminal electrode 7 13 is joined via the first and second joining reinforcing members 8A and 8B to produce the composite multilayer substrate 1, the first and second joints are formed at the joint between the ceramic multilayer substrate 2 and the resin layer 3. Reinforcing members 8A and 8B (joining reinforcing member 8) can be provided, and the ceramic multilayer substrate 2 and the resin layer 3 are firmly joined by these joining reinforcing members 8, and the impact force at the time of dropping, etc. The separation of the ceramic multilayer substrate 2 and the resin layer 3 can be reliably prevented.

In this embodiment, the composite multilayer substrate shown in FIG. 2 is produced.
That is, in this embodiment, the first joint reinforcing member 8A that also serves as the via hole conductor of the joint reinforcing member 8 pierces into the via hole conductor 6 on the resin layer 3 side, and the outside of the circuit pattern 4 and the resin layer 3 of the ceramic multilayer substrate 2 The terminal electrode 7 is electrically connected (see FIG. 2). When the composite multilayer substrate 1 of this embodiment is manufactured, when forming via holes corresponding to the first and second bonding reinforcing members 8A and 8B in the ceramic green sheet 12A and the resin sheet 20, as shown in FIG. Thus, the via hole for the first joint reinforcing member 8A was provided corresponding to the via hole conductor 6 on the resin layer 3 side, and the via hole corresponding to the second joint reinforcing member 8B was formed. The via holes corresponding to the first and second bonding reinforcing members 8A and 8B were formed to have a cross-sectional area of 0.01 mm ² or more and 90% or less of the cross-sectional area of the via-hole conductor 6 of the resin layer 3.

  Next, as shown in FIG. 6, a resin sheet 20 is pressure-bonded to the laminate 12 of the ceramic green sheets 12A to produce a raw ceramic laminate, and then the raw ceramic laminate is fired to produce the ceramic shown in FIG. A multilayer substrate 2 was obtained. As shown in FIGS. 7 and 8, the first joint reinforcing member 8 </ b> A protrudes from the ceramic multilayer substrate 2 so as to pierce the via-hole conductor 6 of the resin layer 3, and the second joint reinforcing member 8 </ b> B is formed of the resin layer 3. It protrudes from the ceramic multilayer substrate 2 so as to pierce the resin part. When this ceramic multilayer substrate 2 is laminated with a resin sheet 13 having via-hole conductors 6 and external terminal electrodes 7 as shown in FIG. 8 and thermally cured, the composite multilayer substrate 1 shown in FIG. The reinforcing member 8 </ b> A pierces the via-hole conductor 6 of the resin layer 3, and the first bonding reinforcing member 8 </ b> B pierces the resin portion of the resin layer 3.

  By the way, when laminating the resin layer 3 on the ceramic multilayer substrate 2, the via hole conductor of the ceramic multilayer substrate 2 is formed even when the conductive resin filling of the via hole conductor 6 of the resin layer 3 is insufficient as shown in FIG. 9. It can be reliably and electrically connected to the via-hole conductor 6 of the resin layer 3 via the first bonding reinforcing member 8A that also serves as the swell, etc., on the bonding surface of the ceramic multilayer substrate 2 as shown in FIG. Even if it is not flat, it can be surely electrically connected to the via-hole conductor 6 of the resin layer 3 via the first joint reinforcing member 8A that also serves as the via-hole conductor of the ceramic multilayer substrate 2 as in the case of FIG. can do.

  In addition, this invention is not restrict | limited to the said embodiment at all. In the above embodiment, the case where the joining reinforcing member is formed of a conductive paste has been described. However, a non-conductive paste may be used as long as it is an inorganic paste that can be formed integrally with a ceramic substrate. The joining reinforcing member is not particularly limited as long as it is formed protruding from the ceramic substrate. For example, a surface mount component may be mounted on the circuit pattern on the upper surface of the ceramic multilayer substrate opposite to the resin layer, that is, the first main surface, and the surface mount component may be covered with a case or thermoset. A resin layer may be formed by coating a resin. Further, the resin layer may be cured after the surface-mounted component is mounted, or the curing and the mounting may be performed simultaneously by one reflow.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used for a composite multilayer board that is mounted as a high-frequency component or the like on a mother board such as a printed wiring board and a manufacturing method thereof.

It is sectional drawing which shows one Embodiment of the composite multilayer substrate of this invention. It is sectional drawing which shows other embodiment of the composite multilayer substrate of this invention. FIG. 3 is a process diagram showing a main part of a process for manufacturing the composite multilayer substrate shown in FIG. 1, and a process diagram for producing a raw ceramic multilayer substrate. It is sectional drawing which shows the ceramic multilayer substrate obtained by baking the raw ceramic multilayer substrate produced at the process shown in FIG. It is process drawing which shows the state which laminates the resin layer on the ceramic multilayer substrate shown in FIG. FIG. 3 is a process diagram showing a main part of a process for manufacturing the composite multilayer substrate shown in FIG. 2, and a process diagram for producing a raw ceramic multilayer substrate. It is sectional drawing which shows the ceramic multilayer substrate obtained by baking the raw ceramic multilayer substrate produced at the process shown in FIG. It is process drawing which shows the state which laminates a resin layer on the ceramic multilayer substrate shown in FIG. It is process drawing which shows the principal part of the process of manufacturing the conventional composite multilayer substrate, and is process drawing which shows the state which laminates a resin layer on a ceramic multilayer substrate. It is process drawing equivalent to FIG. 9 which shows the principal part of the process of manufacturing the conventional composite multilayer substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite multilayer substrate 2 Ceramic multilayer layer 2A Ceramic layer 3 Resin layer 4 Circuit pattern 4B Via-hole conductor 6 Via-hole conductor 7 External terminal electrode 8 Joining reinforcement member 12A Ceramic green sheet 20 Resin sheet

Claims (17)

  A ceramic substrate having a first main surface and a second main surface facing the first main surface; and a resin layer having a first main surface and a second main surface facing the first main surface; And the ceramic substrate has a circuit pattern and the resin layer has a via-hole conductor and an external terminal electrode formed on the second main surface, A composite multilayer substrate in which the circuit pattern and the external terminal electrode are connected via the via-hole conductor, and a bonding reinforcing member that reinforces the bonding force between the ceramic substrate and the resin layer, A composite multilayer substrate, characterized in that at least one is provided toward the substrate.   2. The composite multilayer substrate according to claim 1, wherein the ceramic substrate is formed of a ceramic multilayer substrate formed by laminating a plurality of ceramic layers.   3. The composite multilayer substrate according to claim 1, wherein the bonding reinforcing member is cut into the resin layer side from the ceramic substrate.   The composite multilayer substrate according to any one of claims 1 to 3, wherein the joining reinforcing member is electrically independent from a circuit pattern of the ceramic substrate.   The composite multilayer substrate according to any one of claims 1 to 3, wherein the bonding reinforcing member is formed as a via-hole conductor provided in the ceramic substrate.   The composite multilayer substrate according to claim 5, wherein the bonding reinforcing member constitutes a part of a circuit pattern of the ceramic substrate.   The composite multilayer substrate according to claim 5 or 6, wherein the joint reinforcing member is bitten into a via-hole conductor of the resin layer.   8. The composite multilayer substrate according to claim 5, wherein a cross section of the via hole conductor of the resin layer is formed larger than a cross section of the via hole conductor of the ceramic substrate.   The composite multilayer according to any one of claims 1 to 8, wherein a distal end of the joint reinforcing member is located 5 μm or more inside from each of the first and second main surfaces of the resin layer. substrate. 10. The composite multilayer substrate according to claim 1, wherein a cross-sectional area of the joint reinforcing member is 0.01 to 0.9 mm ² .   11. The composite multilayer substrate according to claim 1, wherein the external terminal electrode is formed of a metal foil.   The composite multilayer substrate according to any one of claims 2 to 11, wherein the ceramic multilayer substrate has a circuit pattern mainly composed of Ag or Cu.   The composite multilayer substrate according to any one of claims 1 to 12, wherein the resin layer contains a chip component.   A step of providing at least one through hole in the resin sheet; a step of filling an inorganic paste in the through hole of the resin sheet; and a step of integrating the resin sheet filled with the inorganic paste and a ceramic green sheet. Firing the ceramic green sheet and the resin sheet to obtain a ceramic substrate and a joining reinforcing member protruding from the ceramic substrate, and joining the ceramic substrate and the resin layer having an external terminal electrode via the joining reinforcing member. A process for producing a composite multilayer substrate.   The method for producing a composite multilayer substrate according to claim 14, wherein a conductive paste is used as the inorganic paste.   The step of providing at least one through-hole in the resin sheet is characterized in that a plurality of the through-holes are provided, and at least a part thereof is provided corresponding to the conductive resin layer formed in the resin layer. 14. A method for producing a composite multilayer substrate according to 14.   The method of manufacturing a composite multilayer substrate according to claim 16, wherein a cross-sectional area of the through hole is smaller than a cross-sectional area of the conductive resin layer.

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