JP6574646B2 - Insulator and wiring board - Google Patents

Description

  The present invention relates to an insulator used for a substrate for a wiring substrate and the like, and a wiring substrate including the insulator.

  An insulator is known that includes a ceramic component such as aluminum oxide and a glass component, and the ceramic component is sintered through the glass component. Such an insulator is used as a member for a wiring board on which electronic components such as a semiconductor element and a surface acoustic wave element are mounted.

  The wiring board has an insulator molded in a predetermined shape such as a flat plate shape, and a wiring conductor provided on the surface of the insulator. An electronic component is mounted on the main surface of the flat insulating base, and an electrode of the electronic component is electrically connected to the wiring conductor. A wiring board on which electronic components are mounted is mounted and used as a component in an electronic device such as a computer, a mobile phone, or various sensors.

JP 2001-52526 A JP-A-6-224042

  However, in the above-described prior art insulator and wiring board, since the insulator contains a ceramic component, mechanical breakdown such as chipping and cracking due to the progress of microcracks caused by impact due to dropping, etc. is caused by the insulator. There was a problem that it was easy to occur.

  In particular, when an insulator is used in a wiring board for mounting electronic components, the wiring board has been significantly downsized in response to the downsizing of electronic equipment in recent years. There is a high possibility of causing trouble. Further, it is difficult to further improve the reliability as a wiring board for electronic equipment.

An insulator according to one aspect of the present invention includes a first phase containing glass and silica containing a siloxane bond as main components, and a second phase containing a crosslinked resin material as a main component. It has a sea-island structure in which the phase is the sea and the second phase is the island, the silica is granular, the granular silica is dispersed in the glass, and the granular silica has an average particle size It consists of a mixture of first fine particles and second fine particles having different diameters, wherein the first fine particles are crystalline silica and the second fine particles are non-crystalline silica. The average particle size is larger than the average particle size of the second fine particles .

  A wiring board according to one aspect of the present invention includes a board including the insulator having the above structure and a wiring conductor provided on a surface of the board.

According to the insulator of one aspect of the present invention, since it contains the first phase mainly composed of glass containing silica and silica and silica, it is sufficient when used for a substrate for a wiring board, for example. Has good mechanical strength. In addition, since the second phase containing a crosslinked resin material having a lower elastic modulus than that of the first phase is contained, even if breakage such as microcracks starts to occur in the first phase, the progress of the microcracks It can be suppressed in the second phase. That is, since the insulator of the above aspect has a sea-island structure in which the first phase is the sea and the second phase is the island, the progress of microcracks in the first phase is hindered by the second phase. Therefore, mechanical destruction that causes a part of the insulator to be chipped or cracked is effectively suppressed. A structure in which the second fine particles having a relatively small average particle size enter the gap between the first fine particles having a relatively large average particle size is obtained, and the mechanical strength as silica particles is improved. Further, the mechanical strength as individual silica particles is improved by the first fine particles, and the stress acting on the silica particles is more effectively absorbed by the deformation of the second fine particles, so that the silica particles Mechanical destruction of itself is suppressed more effectively. Therefore, it is possible to provide an insulator effective for suppressing mechanical breakage such as chipping and cracking.

  According to the wiring board of one aspect of the present invention, since the insulator having the above-described configuration is provided, mechanical destruction such as chipping and cracking in the insulator is effectively suppressed, and the reliability is high. A wiring board can be provided.

It is sectional drawing which shows typically a part of cross section in the insulator of embodiment of this invention. (A) It is a top view which shows the wiring board of embodiment of this invention, (b) is sectional drawing in the AA of (a), (c) is a bottom view. It is sectional drawing which expands and shows an example of the principal part of FIG. 1 typically. It is sectional drawing which expands and shows a part of silica shown in FIG.

  An insulator and a wiring board according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is an enlarged cross-sectional view schematically showing a part of a cross section of an insulator according to an embodiment of the present invention. 2A is a top view showing a wiring board according to an embodiment of the present invention, FIG. 2B is a cross-sectional view taken along the line AA in FIG. 2A, and FIG. FIG. 3 is a cross-sectional view schematically showing an example of an essential part of FIG.

  The insulator 1 has a sea-island structure in which the first phase 2 is the sea and the second phase 3 is the island. Further, the wiring conductor 12 is provided on the surface of the substrate 11 including the insulator 1, and the wiring substrate 10 is basically formed. The wiring board 10 is used for mounting the electronic component 21, for example. An electronic component 21 is mounted on the wiring board 10, and the electronic component 21 and the wiring conductor 12 are connected by a conductive connecting material 22 such as a bonding wire to form an electronic device 20 that is mounted as a component on various electronic devices. The These contents will be described in detail below.

  For example, as in the example shown in FIG. 1, the insulator 1 has a first phase 2 mainly composed of glass 2a and silica 2b containing a siloxane bond, and a second phase 3 mainly composed of a crosslinked resin material. doing. The insulator 1 has a sea-island structure in which the first phase 2 is the sea and the second phase 3 is the island. Since the first phase 2 contains glass 2a containing siloxane bonds and silica 2b as main components, mechanical strength such as bending strength is relatively high. That is, the glass 2a containing a siloxane bond is, for example, a polysiloxane having a three-dimensional structure, and further includes silica 2b having a high mechanical strength, so that the first phase 2 has a high mechanical strength. Moreover, since the 2nd phase 3 has a crosslinked resin material as a main component, its elasticity modulus is comparatively small. Therefore, the insulator 1 can be regarded as having a structure in which particles having a relatively low elastic modulus are microscopically dispersed in a matrix member having a relatively high mechanical strength.

  According to such an insulator 1, since it contains the first phase 2 having the above-described configuration, it has sufficient mechanical strength when used for the substrate 11 for the wiring substrate 10, for example. . In addition, since the second phase 3 having the above-described configuration is included, even if the first phase 2 begins to break down such as microcracks, the progress of the microcracks can be suppressed in the second phase 3. . The first phase 2 has functions such as maintaining the shape of the insulator 1 and ensuring mechanical strength, and the second phase 3 has a function of improving reliability such as suppressing chipping of the insulator 1. Yes.

That is, since the insulator 1 of the embodiment has a sea-island structure in which the first phase 2 is the sea and the second phase 3 is the island, the progress of microcracks in the first phase 2 is the second phase 3. Disturbed by. Therefore, the mechanical destruction that a part of the insulator 1 is chipped or cracked is effectively suppressed. Therefore, it is possible to provide the insulator 1 effective for suppressing mechanical breakage such as chipping and cracking.

  The first phase 2 contains glass (hereinafter also simply referred to as glass) 2a containing siloxane bonds and silica 2b as main components. The glass 2a, which is one of the main components of the first phase 2, is a main structural part that forms the first phase 2 and the insulator 1 as a whole. This glass 2a contains a siloxane bond as described above. In other words, polysiloxane formed by bonding silicon to each other through a siloxane bond forms a predetermined shape as the glass 2 a and is contained as a main component of the first phase 2. Silica 2b, which is another main component of the first phase 2, is bonded to the glass 2a by a siloxane bond and has a function of improving the mechanical strength of the glass 2a. In this case, since the glass 2 a includes a siloxane bond, the bond between the glass 2 a and the silica 2 b becomes strong, and the glass 2 a and the silica 2 b can be integrated as the first phase 2.

In addition, the 1st phase 2 may contain fillers, such as an alumina, a calcia, and magnesia, in addition to a main component. The content ratio of the glass 2a including the siloxane bond as the main component in the first phase 2 and the silica 2b may be set to about 50 to 100% by mass with respect to the entire first phase 2, for example. The mechanical strength as the first phase 2 (insulator 1) can be sufficiently secured.

  The glass 2a having a silanol bond of the first phase 2 is obtained by, for example, hydrolyzing an alkoxyl group or the like into an silanol group and vitrifying the silanol group by condensing the silanol groups. That is, it has a structure in which the alkoxyl group is removed from the organopolysiloxane and the silanol groups are bonded to each other by a siloxane bond.

  Examples of the organosiloxane include methoxysiloxane, ethoxysiloxane, butoxysiloxane, proxysiloxane, and phenoxysiloxane.

  The silica 2b of the first phase 2 is included in the glass 2a as particles as shown in FIG. 1, for example, and is integrated with the glass 2a by a siloxane bond. In this case, for example, as shown in FIG. 3, silanol groups on the surface of the particulate silica 2b are condensed with the silanol groups of the glass 2a to form siloxane bonds.

  As described above, in the first phase 2, the glass 2a as the main component defines the overall shape as the first phase 2, and this is reinforced by the silica 2b to have a certain shape and mechanical strength. A matrix member (base material) is formed.

The second phase 3 is for suppressing the progress of microcracks in the first phase 2 as described above. Therefore, it is preferable that the second phase 3 has a lower elastic modulus, considering only the suppression of the progress of microcracks. In this regard, for example, the second phase 3 preferably has a flexural modulus at −25 ° C. to 125 ° C. of 300 GPa or less, and more preferably 10 GPa or less. However, the second phase 3 also affects the mechanical strength of the insulator 1. Therefore, in consideration of this point as well, the second phase 3 has a flexural modulus of, for example, −25 ° C. to 125 ° C. of 50.
The thing of -300GPa is more preferable.

As the crosslinked resin material forming the second phase 3, a crosslinked resin material such as a crosslinked acrylic resin and a crosslinked urethane resin can be used. Cross-linked resin materials such as cross-linked acrylic resins and cross-linked urethane resins may be used as emulsions finely dispersed in water. Examples of other crosslinked resin materials include epoxy resins, bismaleimide-triazine resins, polyimide resins, thermosetting polyphenylene ether resins, phenol resins, melamine resins, xylene resins, guanamine resins, diallyl phthalate resins, vinyl ester resins, Examples thereof include those obtained by crosslinking at least one of thermosetting resins such as saturated polyester resin, furan resin, polyurethane resin, maleic acid resin and urea resin by thermal reaction. In addition, these cross-linked resin materials may be those that have been preliminarily heat-crosslinked and pulverized.

  In addition, when the crosslinked resin material is at least one of a crosslinked acrylic resin and a crosslinked urethane resin, it is more advantageous in the following points. That is, it is easy to increase the crosslinking density by increasing the ratio of the crosslinking agent. Therefore, the thermal decomposition temperature as the second phase 3 can be further increased. Note that a temperature of about 5% decrease in thermal weight in nitrogen is defined as the thermal decomposition temperature of resin. The thermal decomposition temperature of these crosslinked resin materials is set to about 200 to 350 ° C. in consideration of, for example, the heat resistance of the second phase 3 and the productivity and economy as the insulator 1. The thermal decomposition temperature can be measured by a measuring method such as thermogravimetry / thermobalance (TG-DTA).

  The second phase 3 may contain a resin material such as a thermosetting rubber in addition to the crosslinked resin material such as a thermosetting resin. Moreover, you may further contain additives, such as plasticizers, such as polyethyleneglycol, and an azo pigment agent. In this case, the content rate of the crosslinked resin material as the main component of the second phase 3 is set to about 80 to 98% by mass, for example. In this case, the progress of the crack in the second phase 3 can be more effectively suppressed. Further, the bonding strength of the second phase 3 to the first phase 2 can be further increased.

  Moreover, about the shape of the 2nd phase 3 as an island, the thing of an indefinite shape is mentioned like the example shown in FIG. 1, for example. In this case, it is advantageous with respect to increasing the surface area of the second phase 3 as an island (that is, the area of the bonding interface with the second phase 3). Therefore, it is more effective for improving the bonding strength between the first phase 2 and the second phase 3.

  The shape of the second phase 3 may be a shape other than an indefinite shape such as a spherical shape or an elliptical spherical shape. For example, if the second phase 3 is formed by thermal curing of an uncured thermosetting resin, the second phase can be used if the thermosetting resin before curing is rounded by surface tension. 3 is easier to form, which is more advantageous in terms of productivity and economy as the insulator 1. Further, the second phase 3 may have a wavy surface whose surface is wavy so as to increase the surface area (bonding area with the first phase 2).

  The ratio of the presence of the second phase 3 in the insulator 1 may be set in a range of, for example, a total volume ratio of about the first phase 2: the second phase 3 = 95: 3 to 60:40. In this case, it is possible to obtain a higher effect with respect to chipping prevention while ensuring the mechanical strength as the insulator 1.

  Regarding the form of dispersion of the second phase 3 into the first phase 2, the second phase 3 may be dispersed substantially uniformly in the first phase 2. In this case, the progress of microcracks that are randomly generated in the insulator 1 can be suppressed without deviation in the insulator 1. In addition, the second phase 3 may be dispersed more near the surface of the insulator 1 than inside. In this case, the progress of the microcrack generated from the outer surface of the insulator 1 can be suppressed more effectively.

  In the insulator 1 of the embodiment, for example, as shown in FIG. 3, a silane compound may be interposed at the interface between the first phase 2 and the second phase 3. In this case, the first phase 2 and the second phase 3 are more strongly bonded to each other through the silane compound. Therefore, in this case, the mechanical strength as the insulator 1 can be further increased.

In the example of FIG. 3, the silane compound is a silanol having a group A capable of chemical bonding with the second phase 3, and is a so-called silane coupling agent. The chemical bond with the second phase 3 of the silane compound is, for example, crosslinking with the thermosetting resin of the second phase 3. In this case, oxygen of the silanol group is bonded to the glass 2a or silica 2b of the first phase 2 through a siloxane bond. The silanol group is a siloxane bond with the glass 2a or silica 2b of the first phase 2 by removing some or all of the hydrogen (H) or alkyl group (R) except for the portion where the group A is bonded. It does not matter if they are connected.

  Examples of the group A capable of chemical bonding with the second phase 3 include an epoxy group, an amino group, and a vinyl group. These groups A are bonded to each other by the addition reaction, radical reaction or dehydration condensation reaction with the thermosetting resin of the second phase 3.

  Examples of the silane compound include organosilane and polyalkylsilanol other than the above.

  The silica 2b of the first phase 2 is silicon dioxide, has high electrical insulation, and has a low dielectric loss tangent as an insulating material. Therefore, it is suitable for the wiring board 10 through which a high frequency signal is transmitted. That is, the silica 2 b can function effectively as a component for adjusting the electrical characteristics of the first phase 2. For the first phase 2, for example, when it is preferable to keep the dielectric loss tangent low, the content of silica 2b may be increased.

  The silica 2b is dispersed in the glass 2a as particles, for example, and is combined with the glass 2a by a siloxane bond as described above. Examples of such particles of silica 2b include those having an elliptical shape or a spherical shape (such as an elliptical shape or a circular shape in cross section) as in the example shown in FIG. In the case where the first phase 2 is efficiently filled with silica 2b, spherical silica (spherical silica 2b particles) is preferable. Further, when the silica 2b is a particle, it may have an indefinite shape. In the case where the silica 2b is an irregularly shaped particle, the surface of the silica 2b particle can be provided with a large number of irregularities to increase the area of the bond between the silica 2b and the glass 2a.

  Regarding the glass 2a and the silica 2b which are the main components of the first phase 2, the respective proportions in the main components are the use of the insulator 1, the electrical or mechanical properties required in the use, the productivity and the economy. What is necessary is just to set suitably according to conditions, such as sex. For example, when the insulator 1 is used as the substrate 11 of the wiring board 10 to be described later, in the main component composed of the glass 2a and the silica 2b, the ratio (mass content) of the glass 2a is about 10 to 80% by mass. And the ratio of silica 2b may be set to about 20 to 90% by mass.

  The granular silica 2b may be composed of a mixture of first fine particles 2ba and second fine particles 2bb having different average particle diameters, for example, as shown in FIG. FIG. 4 is a cross-sectional view showing a part of the silica 2b shown in FIG. 4, parts similar to those in FIGS. 1 to 3 are denoted by the same reference numerals.

  In the example shown in FIG. 4, the average particle size of the first fine particles 2ba is larger than the average particle size of the second fine particles 2bb. In each of the following examples including the first fine particles 2ba and the second fine particles 2bb having different average particle sizes, the average particle size of the first fine particles 2ba is larger than the average particle size of the second fine particles 2bb. It will be described as large.

  In the first fine particles 2ba and the second fine particles 2bb, the hydroxyl groups at the interfaces are chemically bonded to each other in the form of a siloxane bond or the like via a silane compound. As a result, a large number of first fine particles 2ba and second fine particles 2bb are gathered into particles to form granular silica 2b (silica 2b particles) in the first phase 2.

In this case, the second fine particles 2bb having a relatively small average particle diameter enter the gap between the first fine particles 2ba having a relatively large average particle diameter, and the machine as a particle of silica 2b. Strength is improved. As a result, the mechanical strength of the insulator 1 is also improved. Therefore, for example, an effective insulator 1 can be provided by improving the mechanical strength of the substrate 11 for the wiring substrate 10 or the like. In addition, the wiring board 10 including the board 11 having higher mechanical strength can be provided.

  The improvement in the mechanical strength of the silica 2b when the silica 2b is a mixture of the first fine particles 2ba and the second fine particles 2bb having different average particle diameters can be obtained between the larger first fine particles 2ba. This is considered to be due to the fact that the small second fine particles 2bb enter the gap and the gap that becomes the starting point of mechanical destruction is reduced.

  The mechanical strength of the insulator 1 can be measured by the bending strength. Moreover, the bending strength of the insulator 1 can be measured by, for example, a general three-point bending test.

  The average particle size of the first fine particles 2ba and the second fine particles 2bb can be measured by, for example, microtrack (laser diffraction scattering method) by dispersing them in water or an organic solvent.

  The ratio of the average particle diameter of the first fine particles 2ba and the second fine particles 2bb is set, for example, in a range of about 2 times or more and about 6 times or less. In this case, the average particle size of the first fine particles 2ba is, for example, about 4 to 6 μm, and the average particle size of the second fine particles 2bb is, for example, about 1 to 2 μm.

  In the example shown in FIG. 4, the first fine particles 2ba may be crystalline silica, and the second fine particles 2bb may be amorphous silica. That is, the first fine particles 2ba are crystalline silica, the second fine particles 2bb are non-crystalline silica, and the average particle size of the first fine particles 2ba is larger than the average particle size of the second fine particles 2bb It may be.

  In this case, mechanical destruction of the silica 2b particles themselves is more effectively suppressed. This is because the mechanical strength of the first fine particles 2ba made of crystalline silica is high, and the elastic modulus of the second fine particles 2bb made of amorphous silica is the elasticity of the first fine particles 2ba (crystalline silica). By smaller than rate. That is, the mechanical strength of the individual silica 2b particles is improved by the first fine particles 2ba, and stress acting on the silica 2b particles is more effectively absorbed by the deformation of the second fine particles 2bb. The

  When the first fine particles 2ba are crystalline silica and the second fine particles 2bb are non-crystalline silica, the second fine particles 2bb can be easily penetrated into the gaps between the first fine particles 2ba. It is also easy to reduce the average particle size of. That is, it is easier to manufacture the insulator 1 in a form including the silica 2b in which the average particle size of the first fine particles 2ba is larger than the average particle size of the second fine particles 2bb.

  The first fine particles 2ba made of crystalline silica are produced, for example, by pulverizing a silicon dioxide crystal material (coarse particles or block shape larger than the first fine particles 2ba) by a method such as mechanical pulverization. can do. The individual first fine particles 2ba produced by pulverization are each formed of crystalline silica. The second fine particles 2bb made of amorphous silica can be produced by spraying and drying liquid silica obtained by a gas phase method, for example. By pulverizing by spraying, second fine particles 2bb each made of amorphous silica are produced.

Further, for example, as in the example shown in FIG. 4, the first fine particles 2ba may be crushed and the second fine particles 2bb may be spherical. In other words, the first fine particles 2ba may be formed of crushed crystalline silica, and the second fine particles 2bb may be formed of spherical amorphous silica. The crushed shape is a shape of fine particles produced by crushing a larger crystal material as described above. For example, an indefinite shape having a plurality of corners and a plane, a polygonal column shape, or a spherical shape having a plurality of protrusions. Alternatively, it has an elliptical spherical shape. The first fine particles 2ba that are crushed may be those containing the above-mentioned shapes and different shapes (so-called irregular shapes).

  When the first fine particles 2ba are crushed and the second fine particles 2bb are spherical, the spherical second fine particles 2bb have a higher density in the gaps between the crushed first fine particles 2ba. Since it enters, the mechanical strength of the silica 2b is further improved. As a result, the mechanical strength of the insulator 1 is further improved.

  In addition, when the silica 2b is a mixture of the first fine particles 2ba and the second fine particles 2bb, either one of the first fine particles 2ba and the second fine particles 2bb is at an extremely large ratio compared to the other. The effect of increasing the mechanical strength of the silica 2b is greater when it is not contained. In other words, it is advantageous in terms of improving the mechanical strength of the silica 2b that the first fine particles 2ba and the second fine particles 2bb are contained in the silica 2b in the same proportion (mass%). is there.

  If the first fine particles 2ba and the second fine particles 2bb are contained in the silica 2b at the same ratio (mass%), the second fineness is such that the gap between the first fine particles 2ba is filled and reinforced. It is easy to ensure the amount of fine particles 2bb. Further, since the ratio of the second fine particles 2bb having a relatively small average particle size is suppressed to be relatively small, the area of the interface between the particles such as the first and second fine particles 2ba and 2bb can be further suppressed. Such an interface tends to be a starting point for mechanical destruction of the silica 2b itself, but since the interface is relatively few, mechanical destruction of the silica 2b itself is more effectively suppressed.

  The insulator 1 of the embodiment can be manufactured as follows, for example.

  That is, first, organosiloxane such as methoxysiloxane and silica powder are prepared as raw materials for the first phase 2. In addition, an emulsion of a resin material such as a cross-linked acrylic resin is prepared as a raw material for the second phase 3. The crosslinked resin material may be thermally crosslinked after mixing. Furthermore, the above silica powder may be prepared by treating a mixture of crystalline silica and amorphous silica with an alkali (aqueous solution) such as potassium hydroxide and then mixing with organosiloxane. This reaction proceeds at room temperature, and a dense insulator 1 is obtained. That is, the productivity and characteristics as the insulator 1 are further improved. The pH during the alkali treatment is preferably in the range of 10-13.

  Next, a slurry prepared by mixing and kneading the raw materials such as powders and granules of these materials with each other is formed into a sheet to produce a green sheet. Examples of a method for forming the slurry into a sheet include a sheet forming technique such as a doctor blade method, a lip coater method, or a calendar roll method. When forming into a sheet, an aqueous solution, a plasticizer or dispersant, a pigment, or the like may be added.

  The insulator 1 is formed by filling the mold with the raw material of the first phase 2 and the raw material of the second phase 3 and molding the compact simultaneously with pressurization and heating described later. Can also be produced.

Next, this green sheet or laminate thereof, or the above-mentioned molded body is heated to cause a condensation reaction in the organosiloxane to bond each other, and a part of the organosiloxane and silica powder are bonded to each other through a siloxane bond. Let At this time, for example, the green sheet may be subjected to punching or the like to be molded into a predetermined shape and size, and a laminate may be produced by stacking a plurality of sheets as necessary.

  Through the above steps, the insulator 1 having a sea-island structure in which the first phase 2 is the sea and the second phase 3 is the island can be manufactured. If the silane compound such as silanol described above is also added to the raw material at the time of manufacturing the insulator 1, the silane compound is interposed between the first phase 2 and the second phase 3, so that the first phase 2 And the second phase 3 can be further strengthened. Therefore, it is possible to produce the insulator 1 that is further excellent in mechanical strength and the like.

  As described above, the wiring substrate 10 is basically formed by the substrate 11 including the insulator 1 having the above-described configuration and the wiring conductor 12 provided on the surface of the substrate 11. The wiring substrate 10 is used as an electronic component mounting substrate, for example, and the electronic component 21 is mounted on the upper surface of the substrate 11 to produce the electronic device 20. The electronic component 21 and the wiring conductor 12 are electrically connected to each other by a conductive connecting material 22 such as a bonding wire.

  In addition to the insulator 1, the substrate 11 may include a coating layer (not shown) that covers a part of the wiring conductor 12, for example. The material for forming the coating layer may be, for example, a cross-linked resin material forming the second phase 3 or another resin material.

  As the electronic component 21, for example, a semiconductor element including a semiconductor integrated circuit element, an imaging element and a light emitting element, a piezoelectric element such as a crystal vibration element and a surface acoustic wave element, a capacitive element (ceramic chip capacitor, etc.), a resistor, a pressure sensor Examples include various sensor elements such as elements, and electromechanical system elements having a fine electromechanical system (so-called MEMS elements).

  The substrate 11 functions as a base for mounting and fixing the electronic component 21 on an exposed surface such as an upper surface. In the example of FIG. 3, the substrate 11 has a rectangular plate shape, and has a concave portion (no symbol) on the upper surface. The substrate 11 having a recess is formed, for example, by providing an opening corresponding to the recess in a part of the green sheet for the substrate 11. The substrate 11 is not limited to this shape, and may be a flat plate shape having no recess, a circular shape, an elliptical shape, or a shape obtained by combining these shapes. Further, the substrate 11 has the above-described shape, and may have a shape having irregularities on a part of the outer periphery in a plan view (viewed from the upper surface side), or may be an indefinite shape.

  The wiring conductor 12 functions as a conductive path for electrically connecting the electronic component 21 to an external electric circuit (not shown). The wiring conductor 12 is provided on an exposed surface such as at least the upper surface of the substrate 11 for electrical connection with the electronic component 21 or the like. Note that the wiring conductor 12 may include those provided inside the substrate 11.

  The wiring conductor 12 is made of a metal material such as copper, silver, lead, zinc, indium, or bismuth. These metal materials are formed in the form of, for example, a coated and heated metal paste, metal foil, plating layer, or thin film layer of the substrate 11.

  If the wiring conductor 12 is made of, for example, copper, a metal paste prepared by kneading copper, a thermosetting resin, solder, and the like with an organic solvent is printed on the surface of the substrate 11 in a predetermined pattern and heated. It can be formed on the substrate 11 by a method such as thermosetting.

For the wiring conductor 12, a metal foil produced using a metal material such as copper or silver is attached to the surface of the substrate 11 (insulator 1), and the metal foil is formed into a predetermined pattern by a pattern forming method such as photolithography. By doing so, you may make it form. The metal foil may be formed into a predetermined pattern before being attached to the substrate 11. Further, a plating layer (not shown) such as copper or silver is deposited on the surface of such a metal foil such as copper or silver so as to increase the thickness (electric conductivity) as the wiring conductor 12. Also good.

  Further, the wiring conductor 12 can be formed on the substrate 11 by a thin film forming method such as a sputtering method and a vapor deposition method. Also in this case, the above plating method may be used in combination.

  In this case, when the wiring conductor 12 is made of a metal material containing at least one of copper and silver as a main component, it is advantageous in the following points. That is, since the electrical resistivity of copper and silver is small, it is easy to suppress the conduction resistance of the wiring conductor 12 formed using these as main components. Since the conduction resistance of the wiring conductor 12 is low, there is little transmission loss, which is advantageous for a high-frequency characteristic substrate (formation of the wiring substrate 10 suitable for transmitting a high-frequency signal).

  The wiring conductor 12 may include a portion provided inside the substrate 11 as described above. In addition to the wiring conductor 12, a through conductor that penetrates at least a part of the substrate 11 in the thickness direction may be provided. In FIG. 2, the through conductor is schematically illustrated using a broken line. The through conductor is disposed inside the insulator 1 and has an end connected to the wiring conductor 12.

  In this example, the upper and lower two through conductors are electrically connected to each other via a wiring conductor 12 (indicated by a broken line connected to the through conductor) provided inside the substrate 11. For example, the wiring conductor 12 on the upper surface of the substrate 11 and the wiring conductor 12 on the lower surface of the substrate 11 are electrically connected to each other through this through conductor or the like.

  The wiring conductor 12 inside the substrate 11 can be formed by the following method, for example. That is, the substrate 11 is composed of a plurality of insulating layers (not shown), and a metal paste that becomes the wiring conductor 12 is applied between the layers (the lower surface of the upper insulating layer or the upper surface of the lower insulating layer). Can be formed. As described above, the substrate 11 including a plurality of insulating layers can be manufactured by stacking a plurality of green sheets to form a stack and heating the stack.

  The through conductor is preferably composed mainly of at least one of copper and silver. This is due to the following reason. In particular, since silver is not easily oxidized, it is not oxidized even in a high-temperature and high-humidity environmental test, and a decrease in conduction resistance is unlikely to occur.

  The through conductor can be formed by the following method, for example. That is, when the green sheet to be the insulator 1 (substrate 11) is punched as described above, a through hole is formed at a position where the through conductor is formed. The through-hole is filled with the above metal paste and heated. Through conductors can be formed by the above steps.

  When the wiring conductor 12 and the through conductor of the wiring board 10 are included and the wiring conductor 12 and the through conductor are made of the same metal material, the bonding strength at the interface between them is improved, and the productivity, etc. This is more preferable. Further, the wiring conductor 12 and the through conductor may be made of different metal materials. For example, considering the suppression of ion migration between the wiring conductors 12 inside the substrate 11 and the economics (cost), the silver content in the wiring conductors 12 and the through conductors inside the substrate 11 is set to The wiring conductor 12 exposed on the surface may be kept smaller than the silver content.

In the wiring substrate 10 of the embodiment, the insulator 1 includes the first phase 2 mainly composed of the glass 2a containing siloxane bonds and the silica 2b, and the second phase 3 mainly composed of the crosslinked resin material. In the high temperature and high humidity acceleration test, the first phase 2 becomes a barrier, for example, from the outside. The penetration of moisture into the two-phase 3 is suppressed. Therefore, the deterioration due to moisture of the crosslinked resin material contained in the second phase 3 is suppressed. Therefore, the wiring board 10 is also excellent in moisture resistance.

  In addition, this invention is not limited to the example of the above embodiment, A various change is possible if it is in the range of the summary of this invention.

  For example, the wiring conductor 12 of the wiring substrate 10 may be one in which a plating layer (not shown) such as nickel and gold is attached to the exposed surface. Further, a multi-cavity wiring board in which a plurality of regions (not shown) to be the wiring board 10 are arranged vertically and horizontally may be used.

DESCRIPTION OF SYMBOLS 1 ... Insulator 2 ... 1st phase 2a ... (The siloxane bond is included) Glass 2b ... Silica 2ba ... 1st fine grain 2bb ... 2nd fine grain 3 ... 1st Two phases
10 ... wiring board
11 ... Board
12 ... Wiring conductor
20 ... Electronic device
21 ... Electronic components
22 ... Conductive connecting material

Claims (7)

A first phase containing glass and silica containing siloxane bonds as main components;
A second phase containing a crosslinked resin material as a main component,
The first phase and the sea, has a sea-island structure that the island the second phase,
The silica is granular, the granular silica is dispersed in the glass,
The granular silica is composed of a mixture of first fine particles and second fine particles having different average particle diameters. The first fine particles are crystalline silica and the second fine particles are non-crystalline. An insulator which is silica and has an average particle size of the first fine particles larger than an average particle size of the second fine particles . The first fine particle is crushed insulator of claim 1, wherein the second fine particles is characterized in that it is spherical. Insulator of claim 1 or claim 2 interface silane compound of the second phase and the first phase is characterized by intervening. The insulator according to any one of claims 1 to 3 , wherein the crosslinked resin material contains at least one of a crosslinked acrylic resin and a crosslinked urethane resin as a main component. A substrate including the insulator according to claim 1;
A wiring board comprising: a wiring conductor provided on a surface of the board. The wiring board according to claim 5 , wherein the wiring conductor is made of a metal material containing at least one of copper and silver as a main component. 7. The semiconductor device according to claim 6 , further comprising a through conductor that has at least one of copper and silver as a main component, is disposed inside the insulator, and has an end connected to the wiring conductor. Wiring board.

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