JP4780995B2 - Glass ceramic sintered body and wiring board using the same - Google Patents

Description

  The present invention relates to a glass-ceramic sintered body that is most suitable for, for example, a wiring board applied to an electrical element storage package, a multilayer wiring board, and the like, and a wiring board using the same.

  The rapid development of information communication technology in recent years has led to higher frequency of information communication equipment, and accordingly, in wiring boards that transmit high-frequency signals, especially to reduce transmission loss of high-frequency signals with a frequency of 100 MHz or higher. In addition, lower resistance of the wiring layer, lower dielectric constant of the insulating substrate, and lower dielectric loss are required. Therefore, it can be densified by firing at 1000 ° C. or lower, and can be simultaneously fired with a wiring layer mainly composed of a low resistance metal such as gold, silver, copper, etc. A wiring board having a low glass ceramic insulating layer has been proposed.

  In addition, with regard to semiconductor elements mainly composed of silicon, in recent years, miniaturization and high speed have been rapidly progressing. Conventionally, SiO2 has been used as an insulating film of a semiconductor element. However, it is well known that, for example, if the insulating film is made porous in order to further reduce its dielectric constant, its mechanical characteristics are significantly reduced. Yes.

  Therefore, when mounting a semiconductor element using such a low dielectric constant insulating film on a package for housing a semiconductor element (hereinafter referred to as primary mounting), it is necessary for curing an underfill agent (curing process). There is a concern that thermal stress is generated due to mismatch of thermal expansion coefficients between the element and the package due to heat treatment or heat generation / cooling of the element due to ON / OFF of the element, and the semiconductor element is destroyed. . Furthermore, since the thermal stress increases with an increase in the size of the device, the risk of the device breaking up increases.

  Therefore, in order to reduce the thermal stress related to the primary mounting, it is required to match the thermal expansion coefficient of the package with the thermal expansion coefficient of silicon (2 to 4 ppm / ° C .: 40 to 400 ° C.).

  For example, it is described that a multilayer ceramic circuit board having a low thermal expansion coefficient can be obtained by using a glass ceramic sintered body made of mullite, quartz glass, or borosilicate glass as an insulating material (see Patent Document 1).

For example, low resistance wiring is possible by combining a borosilicate glass made of SiO ₂ , B ₂ O ₃ , K ₂ O, and Al ₂ O ₃ with alumina, cordierite (agree with cordierite), and quartz glass. It is described that a glass ceramic substrate having a low dielectric constant can be obtained (see Patent Document 2).
Japanese Patent Publication No. 4-058198 JP-A-5-254923

However, in the above-mentioned Patent Documents 1 and 2, among the two or more types of glass, quartz glass and borosilicate glass, which are the raw materials used, quartz glass generally has a content of SiO 2 that is a network-forming oxide of 99. .5% by mass or more glass, which is amorphous, but typically, for example, monovalent metal elements such as alkali metal oxides, alkaline earth metal oxides, B ₂ O ₃ , It consists of a valent metal element and a trivalent metal element, contains almost no softening component that lowers the softening point of glass, and contains 99.5% by mass or more of SiO ₂ that is a non-softening component. The point is very high at 1600 degrees or more, and since it does not soften at a temperature of about 1000 ° C., quartz glass behaves as a filler although it is described as glass, and contributes to sintering. Never happen.

  For example, quartz glass that does not substantially contain such a softening component is difficult to manufacture, and therefore has a unit price that is twice or more that of general glass and is very expensive. In addition, the unit price is several tens of times higher than that of a general filler.

  That is, such a glass that does not substantially contain a softening component, such as quartz glass, does not have a function of improving sinterability and is expensive, and thus is difficult to manufacture and is very expensive. There is a problem of becoming a glass ceramic sintered body.

  In addition, the glass ceramic sintered body described in Patent Documents 1 and 2 using one or more kinds of glass containing a conventional softening component and quartz glass substantially not containing a softening component has low resistance. Because metal is used as a conductor and has a low dielectric constant, signal transmission at a relatively low frequency is possible.
Although excellent in reducing the transmission loss, there is still a problem that the dielectric loss at a high frequency of 100 MHz or more is large, and thus the transmission loss at a high frequency becomes large.

  For example, instead of the quartz glass used in Patent Documents 1 and 2, even if a glass containing a softening component that softens at a temperature of 1000 ° C. or lower is used, the two types of glass are softened and flowed together during the firing process. Therefore, two or more kinds of glass phases having different compositions do not remain in the glass ceramic sintered body, and only one glass phase remains in the glass ceramic sintered body.

  That is, a glass ceramic sintered body containing two or more kinds of glass phases substantially containing a softening component and crystals has not been reported yet.

  Such a glass ceramic sintered body containing two or more glass phases substantially containing a softening component and crystals has an unprecedented structure, and thus has an unprecedented excellent characteristic. It is expected to be a ceramic sintered body.

Accordingly, the present invention is a glass ceramic that contains two or more glass phases containing 1% by mass or more of the total amount of the softening component in terms of oxide and crystals, and has a low dielectric constant, low dielectric loss, and low thermal expansion coefficient. It aims at providing a sintered compact and a wiring board using the same.

The glass-ceramic sintered body of the present invention contains cordierite and SiO ₂ in an amount of 80 to 95% by mass , and at least one selected from the group consisting of B ₂ O ₃ , Al ₂ O ₃ , Mg ₂ O, CaO and BaO. a glass phase α1 containing 1-5 wt% or more species in a total amount, and a glass phase α2 of different composition with the glass phase, dielectric loss at 2GHz is 20 × ^{10 -4} or less, a dielectric constant of 7 or less And a thermal expansion coefficient at 40 to 400 ° C. is 5 × 10 ⁻⁶ / ° C. or less.

  The wiring board of the present invention comprises the insulating substrate made of the glass ceramic sintered body described above, and a wiring layer mainly composed of any one of gold, silver, and copper on at least the surface thereof.

According to the present invention, a glass ceramic sintered body having a low dielectric constant, a low dielectric loss, and a low thermal expansion coefficient, and a wiring board using the same can be obtained.

As shown in FIG. 1, the glass ceramic sintered body of the present invention has a glass phase α and a crystal phase β, and contains two or more phases (α1 and α2 in the figure) having different compositions as the glass phase. , and the a cordierite with containing SiO ₂ 80 to 95 _{wt%, B 2 O 3, Al} 2 O 3, Mg O, at least one selected from CaO and BaO group of a total of 1 It has a glass phase α1 containing ˜5% by mass and a glass phase α2 having a composition different from that of the glass phase . Here, B ₂ O ₃ , Al ₂ O ₃ , MgO, CaO, and BaO are metal oxides of a softening component that can lower the softening point of the glass phase.

  The total amount of the softening component in terms of oxide is the composition analysis means such as XRF (fluorescence X-ray analysis), ICP (inductively coupled plasma) emission analysis, atomic absorption spectrophotometry, etc., and TEM (transmission electron microscope). ) And an XMA (X-ray microanalyzer) attached thereto.

  Specifically, the content of each element can be measured by specifying a glass phase using TEM and performing composition analysis of the glass phase using XMA attached to the TEM.

  However, in XMA, it is impossible to measure a light element having an atomic number smaller than N (nitrogen). Therefore, when such a light element is contained, each of the light elements can be directly measured by using TEM-XMA. It is impossible to measure the content of the components.

  Therefore, in that case, the content of each component is calculated by the following method. First, the component contained in the glass ceramic is identified by XRF, ICP, or atomic absorption spectrophotometry. Thereafter, the content of each element is measured using TEM-XMA in the same manner as described above.

  Then, oxygen is allocated to elements other than light elements so as to have a stoichiometric composition. For example, 2 mol% of oxygen is allocated to 1 mol% of Si, and 3 mol of oxygen is allocated to 2 mol of Al. After assigning oxygen to all the elements in this way, a light element corresponding to the number of moles of remaining oxygen is assigned, and the assigned number of moles is calculated as the content of the light element.

In the conventional glass ceramic sintered body, if the SiO ₂ content of the glass component is increased, the softening point of the glass becomes too high, so the content of SiO ₂ of the glass component with respect to sinterability at 1050 ° C. or lower. Naturally there was a limit to increasing it. Further, when quartz glass is used as the filler, there is a problem that the cost increases.

On the other hand, according to the glass ceramic sintered body of the present invention, a glass ceramic sintered body containing a glass phase containing a large amount of SiO ₂ is realized while maintaining sinterability at 1050 ° C. or lower. Thus, a low dielectric constant, a low dielectric loss, and a low thermal expansion coefficient can be realized.

Here, in the glass-ceramic sintered body of the present invention, the glass phase contains 80 to 95% by mass or more of SiO ₂ , which is effective in reducing the dielectric loss at low dielectric constant and high frequency.

Furthermore, the ratio of the glass phase containing 80 to 95% by mass of SiO ₂ may be two or more, and is preferably 20% or more, more preferably 30% or more in the total glass phase.

Furthermore, the glass phase containing 80 to 95% by mass of SiO ₂ contains 1 to 5% by mass of at least one selected from the group consisting of ZnO, CaO and BaO. Thereby, low dielectric loss can be realized.

  Since at least one selected from the group of ZnO, CaO and BaO is a component that increases the dielectric constant and dielectric loss of the glass phase, when the content is larger than the above range, the dielectric constant and the dielectric loss In particular, the dielectric loss at high frequencies may increase.

In addition, the sintered glass ceramic of the present invention has a dielectric loss of 2 × 10 ⁻⁴ or less and a dielectric constant of 7 or less at 2 GHz, and further a dielectric loss of 15 × 10 ⁻⁴ or less, optimally 10 ×. It can be 10 ⁻⁴ or less, the dielectric constant is 6.5 or less, and optimally 6.0 or less.

The glass ceramic sintered body of the present invention is at least _SiO 2: twenty to fifty-three _{wt%, B} 2 O 3: _{2~14 wt%, Al} 2 O 3: _20~61 wt%, MgO: 2 to 24 mass And at least one selected from the group consisting of ZnO, CaO, SrO and BaO in a total amount of 1 to 5% by mass.

  When the components constituting the glass-ceramic sintered body are in the above range, it is easy to fire simultaneously with low resistance wiring such as gold, silver and copper, and has a lower dielectric constant and lower dielectric loss than alumina. A ceramic sintered body is obtained.

Particularly desirable ranges of the composition of the glass ceramic sintered body are SiO ₂ : 25 to 48 mass%, B ₂ O ₃ : 3 to 11 mass%, Al ₂ O ₃ : 28 to 55 mass%, MgO: 4 to 18 The total amount of at least one selected from the group of mass%, ZnO, CaO, SrO and BaO is 1 to 5 mass%.

  Further, the glass ceramic sintered body of the present invention has a Pb, Cd, As content of 0.01% by mass or less in terms of oxide, particularly in order to suppress adverse effects on the human body and the environment as much as possible. It is desirable that it is 0.005 mass% or less.

  Furthermore, the glass-ceramic sintered body of the present invention may contain at least one selected from the group consisting of alumina, garnite, spinel, mullite, forsterite, enstatite, anorthite, slusonite, serdian and zirconia as a crystalline phase. desirable. By arbitrarily combining these crystal phases, the characteristics of the glass ceramic sintered body, for example, characteristics such as dielectric constant, dielectric loss, thermal expansion coefficient, and bending strength can be adjusted according to the application.

  These crystal phases may be precipitated from the glass powder or may be added as a ceramic powder, and the formation method is not limited.

Moreover, by setting the glass ceramic sintered body of the present invention as such a configuration, the thermal expansion coefficient at 40 to 400 ° C. can be made 5.0 × 10 ⁻⁶ / ° C. or less, and further 4.5 × 10 6 It is also possible to set it to ⁻⁶ / ° C. or less, optimally 4.0 × 10 ⁻⁶ / ° C. or less.

  Below, the manufacturing method of a glass ceramic sintered compact is demonstrated.

  The method for producing a glass ceramic sintered body comprises a step of mixing and forming glass powder and cordierite powder and firing at a temperature of 1000 ° C. or less, and separating the glass powder in the firing step. It is characterized by making it.

  By producing a glass-ceramic sintered body by such a production method, a glass phase having a low dielectric constant and low dielectric loss can be generated by phase separation. As a result, simultaneous with a low-resistance metal such as gold, silver, or copper. It is possible to obtain a sintered glass ceramic that can be fired and has both a low dielectric constant and a low dielectric loss.

  Here, in the method for producing a glass ceramic sintered body, the glass powder is preferably crystallized glass in which at least one kind of precipitated crystal phase is precipitated during firing.

  As a result, the composition of the glass powder is changed by crystallization, and the phase separation of the residual glass is promoted. As a result, the dielectric constant and dielectric loss can be further reduced.

  Here, by depositing a cordierite crystal phase having the characteristics of a low dielectric constant, a low dielectric loss and a low thermal expansion coefficient as a precipitated crystal phase, it has a lower dielectric constant and lower dielectric loss than alumina, and Makes it possible to easily achieve a low thermal expansion coefficient similar to that of a silicon chip.

  This is because cordierite powder, which is the same crystal as the precipitated crystal phase, acts as a nucleating agent that promotes crystallization, thereby further promoting the phase separation of the residual glass phase, further reducing dielectric loss. It is because it can plan.

In the manufacturing method of a glass ceramic sintered body, as the glass powder, at least _{SiO 2, Al 2 O 3,} MgO, a borosilicate glass powder containing B 2 _{O 3} from 60 to 99.5 wt%, Kodie 0.5 to 20% by mass of light powder, and at least selected from the group consisting of alumina, garnite, spinel, mullite, forsterite, enstatite, anorthite, slusonite, serdian, zirconia, CaZrO ₃ and CaSiO ₃ It is desirable to add 0 to 35 mass% of one kind of metal oxide powder.

  As described above, the combination of the glass powder, cordierite powder, and metal oxide allows the fillers to be efficiently aligned by the softening flow of the glass. As a result, the pores are reduced at a lower temperature and in a shorter time. A dense sintered body can be obtained. The particle size of the borosilicate glass powder and cordierite powder is 0.5 to 10 μm, preferably 0.8 to 7 μm, and most preferably 1 to 5 μm.

  The reason why the amount of the borosilicate glass powder is limited to the above range is that when the amount of the glass powder is less than 60% by weight, the sintered body cannot be densified at a low temperature of 1000 ° C. or less. On the other hand, if the amount is more than 99.5% by weight, the sintered body cannot maintain its original shape due to the flow of glass during firing. A more desirable range of the borosilicate glass powder is 65 to 88.5% by mass.

Here, SiO ₂ , Al ₂ O ₃ , and MgO are effective for precipitating the cordierite crystal phase from the glass to obtain a lower thermal expansion coefficient and dielectric constant, and B ₂ O ₃ is used for softening the glass. It is a softening component that has a particularly high effect of lowering the point.

  On the other hand, cordierite powder has a low dielectric constant, low dielectric loss, and low thermal expansion coefficient as described above, and more cordierite crystal phases are precipitated from the glass powder with cordierite powder as the core. Therefore, the phase separation of the glass can be promoted, and a lower dielectric constant, a lower dielectric loss, and a lower thermal expansion coefficient can be realized.

  Here, by making the amount of cordierite powder 0.5% by mass or more, it becomes easy to lower the thermal expansion coefficient of the sintered body to a value approximated to silicon, and 20% by mass or less. By doing so, it becomes possible to densify the sintered body at a low temperature of 1000 ° C. or lower.

  Furthermore, it is desirable that the amount of the metal oxide powder is within the above range. By making the amount of the metal oxide powder 35% by mass or less, the sintered body is densified at a low temperature of 1000 ° C. or less. It is because it becomes easy to do. The more preferable range of the cordierite powder is 1.5 to 15% by mass, and the more preferable range of the metal oxide powder is 10 to 30% by mass.

Furthermore, in the manufacturing method of a glass ceramic sintered body, borosilicate glass powder is at least _SiO 2: 30 to 55 _{wt%, Al} 2 O 3: _15~40 wt%, MgO: 3 to 25 wt%, _{B 2} O ₃ : 2 to 15% by mass, BaO: 10 to 40% by mass, and further containing at least one selected from the group consisting of ZnO, CaO, SrO and BaO in a total amount of 0 to 10% by mass It is desirable to use

The reason why the component of the borosilicate glass is within the above-mentioned range is that optimum softening characteristics for obtaining a dense sintered body can be obtained and phase separation can be effectively promoted. Conversely, if the composition of the borosilicate glass powder deviates from the above range, it becomes difficult to obtain a glass ceramic sintered body having desirable ceramic characteristics at a firing temperature of 1000 ° C. or less.

  In addition, ZnO, CaO, and BaO can control porcelain characteristics by precipitating garnite crystal phase, anorthite crystal phase, sulsonite crystal phase, Serdian crystal phase, etc. from the glass while controlling the softening behavior of borosilicate glass. It becomes possible. Furthermore, CaO is effective for improving the chemical resistance of the glass ceramic sintered body.

More desirable ranges of the components of the borosilicate glass are SiO ₂ : 35 to 50% by weight, Al ₂ O ₃ : 20 to 35% by weight, MgO: 5 to 20% by weight, B ₂ O ₃ : 4 to 12% by weight. %, BaO: 10 to 40% by mass, and at least one selected from the group consisting of ZnO, CaO and BaO is 0 to 10% by mass in total.

In the method for producing a glass ceramic sintered body, the metal oxide powder is selected from the group consisting of alumina, garnite, spinel, mullite, forsterite, enstatite, anorthite, slausonite, serdian, zirconia, CaZrO ₃ and CaSiO _3. It is desirable to contain at least one kind.

In the method for producing a glass ceramic sintered body, at least one of these metal oxides selected from the group consisting of alumina, garnite, spinel, mullite, forsterite, enstatite, anorthite, slausonite, serdian, zirconia, CaZrO ₃ and CaSiO ₃ By arbitrarily combining the powders, characteristics such as dielectric constant, dielectric loss, thermal expansion coefficient, and bending strength of the glass ceramic sintered body can be adjusted according to the application. In particular, it is effective to select alumina for increasing the bending strength and zirconia and CaZrO3 for improving chemical resistance.

  In the present invention, for example, a glass phase having a low dielectric constant can be realized without using quartz glass. However, this does not deny the use of quartz glass as a filler, and it is appropriately used as necessary. Needless to say.

  FIG. 2 shows a wiring board of the present invention using the glass ceramic sintered body described above as an insulating layer.

  As shown in FIG. 2, the wiring board 3 of the present invention comprises an insulating substrate 1 and a wiring layer 5 mainly composed of gold, silver, or copper on at least the surface thereof. The glass-ceramic sintered body 1 of the present invention is used.

  The wiring substrate 3 of the present invention can control important characteristics of the insulating substrate 1 such as dielectric constant and strength by configuring the insulating substrate 1 with the glass ceramic sintered body 1 of the present invention. it can. In particular, with respect to dielectric constant and dielectric loss, very excellent characteristics can be achieved, and in particular, it can be suitably used for high frequency applications such as MPU.

  Below, the manufacturing method of the wiring board 3 of this invention is demonstrated.

First, for example, at least SiO ₂ : 20 to 53% by mass, B ₂ O ₃ : 2 to 14% by mass, Al ₂ O ₃ : 20 to 61% by mass, MgO: 2 to 24% by mass, A suitable amount of a glass powder containing 0 to 10% by mass of at least one selected from the group of ZnO, CaO, SrO, and BaO and cordierite powder is weighed, and an appropriate organic resin binder, solvent, etc. After adding and mixing, it is molded into an arbitrary shape by a desired molding means such as a die press, cold isostatic pressing, injection molding, extrusion molding, doctor blade method, calendar roll method, rolling method and the like. In particular, a doctor blade method is suitable for producing a green sheet.

  Next, a through hole for forming a via hole conductor is formed in the ceramic green sheet by punching or laser processing, and at least one selected from the group of Cu, Ag, Au is contained as a main component in the through hole. Filling the containing conductive paste, and transferring the conductive paste to a printing method such as a screen printing method or a gravure printing method or a transfer film formed with a metal foil of a predetermined wiring pattern formed on the surface to the green sheet surface The pattern of the internal wiring layer and the connection electrode is formed by, for example. Then, if necessary, a green sheet on which a metallized wiring layer and a via-hole conductor are formed is laminated in the same manner as described above.

  Next, when the above-mentioned molded body is fired, first, the binder component blended for molding is removed. The removal of the binder is performed in an air atmosphere around 500 ° C. when using Ag, Au as the conductor material, and in a nitrogen atmosphere containing water vapor around 700 ° C. when using Cu as the conductor material. Done.

  The glass powder is phase-separated by baking for 0.2 to 10 hours, particularly 0.5 to 5 hours in an oxidizing or non-oxidizing atmosphere at 700 to 1000 ° C. α2 is formed.

  In addition, about the said baking, when co-firing with conductor materials, such as Cu, it calcinates in non-oxidizing atmospheres, such as nitrogen, nitrogen / water vapor | steam mixing, nitrogen / hydrogen mixing atmosphere, where a conductor material is not oxidized. As a result, the wiring substrate 3 having connection electrodes, internal wiring layers, and via-hole conductors can be obtained.

  At this time, if the firing temperature is lower than 700 ° C. or the firing time is shorter than 0.2 hours, the phase separation may be insufficient, and the effect of reducing the dielectric constant and dielectric loss may be insufficient. If the firing temperature exceeds 1000 ° C. or the firing time is longer than 10 hours, the voids in the sintered body may increase or the shape of the sintered body may collapse.

  An electrical element such as a semiconductor element is mounted on the surface of the wiring board 3 and connected to the connection electrode through the internal wiring layer and via-hole conductor so that signals can be transmitted. As the connection method, flip-chip mounting using solder shown in the drawing, wire bonding, and further a mode of directly mounting on the wiring layer and connecting are preferable.

  Note that the electric element is not limited to a semiconductor element, and a plurality of electronic components such as various capacitors and filters can be mounted.

  Furthermore, an underfill agent is filled in the gap between the electric element and the wiring board 3 and cured, or a potting resin is coated on the electric element and cured, or the same kind of insulating material as the insulating substrate 3 or other insulating materials Alternatively, the wiring board 3 on which the electric element is mounted can be manufactured by bonding a lid made of a metal or the like having good heat dissipation properties with an adhesive such as glass, resin, or brazing material.

  Further, a solder ball made of high melting point solder is connected to the lower surface of the wiring board 3 by solder made of low melting point solder. When this wiring board is mounted on a printed board, the solder balls of the package are placed on the connection electrodes of the printed wiring board via solder on the surface of the printed board, and solder reflow processing is performed. The wiring board 3 can be secondarily mounted on the printed board.

  In order to confirm the effect of the wiring board of the present invention, a multilayer wiring board for evaluation was produced as follows. First, a glass having the composition shown in Table 1 was prepared. The average particle size was 2 μm.

  These glass powders were mixed according to the composition of Table 2 using filler powders shown in Table 2 having an average particle diameter of 1 to 2 μm.

  Then, an organic binder, a plasticizer, and toluene were added to this mixture to prepare a slurry, and then a green sheet having a thickness of 300 μm was produced using this slurry by a doctor blade method. Further, a plurality of the green sheets were laminated so as to have a desired thickness, and thermocompression bonded by applying a pressure of 10 MPa at a temperature of 60 ° C.

  The obtained laminate was treated to remove the binder at 750 ° C. in a nitrogen atmosphere, then heated at 200 ° C./hour, and fired in the air under the conditions shown in Table 2 to sinter the glass ceramic for evaluation of the insulating substrate. Got the body.

  About the obtained sintered compact, the presence or absence of phase separation and the content of SiO2 in the glass phase were measured using TEM (transmission electron microscope) and XMA (X-ray microanalyzer) attached to TEM. At this time, for the phase-separated one, the one having a larger SiO2 content was α1, and for the one without the phase-separated, the whole glass phase was regarded as α1 and measured.

  Moreover, it processed to 50 mm □ and thickness 1.0mm, and measured the dielectric constant and dielectric loss in 2 GHz with the cavity resonator method.

  Furthermore, the sintered body was processed to 2 mm □ and 18 mm in length, and the dimensional change was measured with a laser rangefinder while firing at a rate of 10 ° C./min. It was measured.

In addition, the sintered bodies were pulverized, the crystal phases were identified from the X-ray diffraction measurement, and arranged in descending order of main peak intensity. The above measurement results are shown in Table 2.

As is clear from the results in Tables 1 and 2, the sample No. 1 was obtained by separating the glass phase based on the present invention. 1, 2, 4, 6, 8 to 18, the dielectric constant at 2 GHz is 7 or less, the dielectric loss is 20 × 10 ⁻⁴ or less, and the thermal expansion coefficient at 40 to 400 ° C. is also 5 × 10 ⁻⁶ / ° C. or less. And showed good values.

  On the other hand, sample no. In 3, 5, 7, and 19-22, the dielectric loss became large.

  Sample No. 1 of Example 1 An acrylic binder, a plasticizer, and toluene were added to and mixed with the raw material powders of 1, 2, 4, 6, 8 to 18, and a green sheet having a thickness of 300 μm was produced by a doctor blade method. Next, via holes were formed at predetermined positions on the green sheet and filled with a conductor paste mainly composed of copper, and then a wiring layer was formed on the surface of the green sheet using the conductor paste by a screen printing method.

  Then, four green sheets on which the wiring layer was formed were stacked and thermocompression bonded while being aligned. This laminate was fired in steam-containing nitrogen under the firing conditions shown in Table 2 to produce a multilayer wiring board having a wiring layer mainly composed of copper.

  With respect to the obtained wiring board, the continuity of the wiring layer and the transmission characteristics at 2 GHz were confirmed. As a result, there was no disconnection or the like, and a low resistance and good continuity characteristics and good transmission characteristics were shown.

Further, a conductive paste mainly composed of copper is formed on the surface of the green sheet by a screen printing method, and a flip chip pad is formed on the surface of the package A with 0.12 mmφ pads arranged in a matrix. A ball pad having 1 mmφ pads arranged in a matrix was formed. The green sheets were laminated and cut so that the shape after firing was 30 mm □ and the thickness was 1.5 mm, and then fired under the conditions shown in Table 2. After performing Ni-Au plating on the obtained wiring board, printing a eutectic solder paste on the pad, aligning and placing a 1.2 mmφ high-temperature solder ball, and performing a reflow process, A wiring board A on which high-temperature solder balls were mounted was produced.

  Next, the semiconductor element 5 mainly composed of silicon and having a thermal expansion coefficient of 3 × 10 −6 / ° C. is placed on the surface of the package A with solder balls aligned and subjected to a reflow process, and then an epoxy resin. A semiconductor element was flip-chip mounted by injecting an underfill agent consisting of the above into the gap between the semiconductor element and the package A and curing it.

  The sample subjected to the primary mounting was subjected to a temperature cycle test in the temperature range of 0 to 100 ° C. for 2000 cycles. As a result, none of the samples showed disconnection or destruction of the semiconductor element until 2000 cycles, and showed good long-term reliability of the connection part.

It is sectional drawing which shows the structure | tissue of the glass ceramic sintered compact of this invention. It is sectional drawing which shows an example of the wiring board which uses the glass ceramic sintered compact of this invention as an insulating substrate.

α1 Glass phase α2 Glass phase β Crystal phase 1 Insulating substrate 3 Wiring substrate 5 Wiring layer

Claims (2)

And cordierite, as well as containing SiO ₂ 80 to 95 _{wt%, B 2 O 3, Al} 2 O 3, Mg O, 1~5 wt in total amount of at least one or more selected from CaO and BaO group of % Glass phase α1 and glass phase α2 having a composition different from that of the glass phase , the dielectric loss at 2 GHz is 20 × 10 ⁻⁴ or less, the dielectric constant is 7 or less, and the heat at 40 to 400 ° C. A glass-ceramic sintered body having an expansion coefficient of 5 × 10 ⁻⁶ / ° C. or less.   A wiring substrate comprising the insulating substrate made of the glass ceramic sintered body according to claim 1 and a wiring layer mainly composed of gold, silver, or copper on at least a surface thereof.

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