JP6632995B2 - Ceramic body and method of manufacturing the same - Google Patents

Description

  The present invention relates to a ceramic base, and more particularly to a ceramic base suitable for use in a ceramic package or a high-frequency circuit board in which elements such as a vibrator are mounted, and a method of manufacturing the same.

Conventional ceramic bodies, for example, ceramic bodies described in Japanese Patent No. 2883787, Japanese Patent No. 3176815 and Japanese Patent No. 4717960 as ceramic bases mainly containing alumina (Al ₂ O ₃ ) and zirconia (ZrO ₂ ) are known. Are known.

  Japanese Patent No. 2883787 discloses that a main component contains 70 to 90% by mass of alumina and 10 to 30% by mass of zirconia, and 0.5 to 2.0% by mass of yttrium (Y) and calcium (Ca) as additives. A ceramic base containing 0.5 to 2.0% by mass, magnesium (Mg) 0.5 to 2.0% by mass, and cerium (Ce) 0.5 to 2.0% by mass is described.

  Japanese Patent No. 3176815 contains 82 to 97% by mass of alumina and 2.5 to 17.5% by mass of zirconia as main components, and 0.1 to 2.0% by mass of yttrium (Y) as an additive. A ceramic body containing 0.02 to 0.5% by mass of calcium (Ca) and 0.02 to 0.4% by mass of magnesium (Mg) is described.

  Japanese Patent No. 4717960 describes a ceramic body composed of alumina as a main component, partially stabilized zirconia as a subcomponent, and magnesia. In this ceramic body, the content of the partially stabilized zirconia is in the range of 1 to 30% by weight based on the total weight of the powder material, and the content of magnesia is 0.1% based on the total weight of the powder material. The molar fraction of yttria in the partially stabilized zirconia is in the range of 0.015 to 0.035.

  Generally, the Young's modulus of a ceramic body increases as the bending strength increases. When the Young's modulus is high, it is difficult to deform and becomes brittle, so that cracks are liable to occur, and chipping at the time of chip division is liable to occur.

  In package applications in which a vibrator or the like is mounted, a ceramic base on which an electrode layer and a wiring layer are formed can be obtained by simultaneously firing a ceramic molded body and a metal film. In such a case, if the Young's modulus of the ceramic base material is increased, cracks are likely to be generated due to bending stress in small and low-profile package applications mounted on wearable devices, IC cards, and the like.

  However, in the above-mentioned Japanese Patent No. 2883787, Japanese Patent No. 3176815 and Japanese Patent No. 4717960, there is a description about bending strength, but no consideration is given to Young's modulus.

  The present invention has been made in consideration of such problems, and is suitable for a high-frequency circuit board, and has a high bending strength, a low Young's modulus, and a product using a ceramic substrate (a ceramic package, a high-frequency It is an object of the present invention to provide a ceramic body capable of realizing miniaturization of a circuit board for use at low cost and a method of manufacturing the same.

[1] The ceramic body according to the first aspect of the present invention has a crystal phase whose main crystal phase is Al ₂ O ₃ and ZrO ₂ , and further includes Mn ₃ Al ₂ (SiO ₄ ) ₃ or MgAl ₂ O ₄ , bending strength 650M P a higher Young's modulus is equal to or less than 300 GPa.

[2] In the first aspect of the present invention, the bending strength is preferably 650 MPa to 1100 MPa, and the Young's modulus is preferably 240 GPa to 300 GPa.

[3] In the first aspect of the present invention, it is preferable that the dielectric loss tangent at 1 MHz is 200 × 10 ⁻⁴ or less and the relative dielectric constant is 10 to 15.

[4] In the first invention, it is preferable that the sintering is performed at a temperature of 1250 to 1500 ° C.

[5] In the first aspect of the present invention, from 70.0 to 90.0 wt% of Al in terms of Al ₂ O _3, 10.0 to 30.0 wt% of Zr in terms of ZrO _2, Al ₂ O ₃ and ZrO Assuming that the total of ₂ is 100% by mass, Mn is 2.0 to 7.0% by mass in terms of MnO, Si is 2.0 to 7.0% by mass in terms of SiO ₂ , and Ba is 0.5 to 0.5% in terms of BaO. ２．０2.0 mass%, and preferably 0-2.0 mass% of Mg in terms of MgO. For Mn, Ba, and Mg, carbonates can also be used.

[6] In the second method for producing a ceramic body according to the present invention, Al is 70.0 to 90.0% by mass in terms of Al ₂ O ₃ , and Zr is 10.0 to 30.0% by mass in terms of ZrO _2. , when the sum of the _Al 2 _{O 3} and ZrO ₂ is 100 mass%, 2.0 to 7.0 mass% of Mn in Mn O conversion calculation, 2.0 to 7.0 wt% of Si in terms of SiO ₂ A compact forming step of preparing a compact containing 0.5 to 2.0% by mass of Ba as BaO and 0 to 2.0% by mass of Mg as MgO; And a firing step of firing.

[7] In the second aspect of the present invention, the method further includes a step of forming a conductor layer containing a metal on the molded body after the molded body production step, and in the firing step, the molded body on which the conductor layer is formed. May be fired.

[8] In the second aspect of the present invention, the firing step may be performed in a forming gas of hydrogen and nitrogen containing 5% or more of hydrogen.

According to the ceramic body and the method of manufacturing the same according to the present invention, the following effects can be obtained.
(A) High bending strength and low Young's modulus.
(B) It is also suitable for high frequency circuit boards.
(C) The chipping occurrence rate at the time of chip division is also small.
(D) Breakage due to bending stress when mounted as a package component or the like is difficult.
(E) Cracks are less likely to occur during brazing.
(F) The yield can be improved, and miniaturization of a product (ceramic package, high-frequency circuit board, etc.) using a ceramic base can be realized at low cost.

FIG. 2 is a cross-sectional view showing a first configuration example (first package) using a ceramic body according to the present embodiment. FIG. 4 is a process block diagram illustrating a method for manufacturing a ceramic body according to the present embodiment, together with a method for manufacturing a first package. FIG. 9 is a cross-sectional view illustrating a second configuration example (second package) using the ceramic base according to the present embodiment. It is a process block diagram which shows the manufacturing method of the ceramic body based on this Embodiment with the manufacturing method of a 2nd package.

  Hereinafter, embodiments of a ceramic body and a method of manufacturing the same according to the present invention will be described with reference to FIGS. In this specification, “to” indicating a numerical range is used as a meaning including numerical values described before and after the numerical range as a lower limit and an upper limit.

In the ceramic body according to the present embodiment, the crystal phase has Al ₂ O ₃ and ZrO ₂ as main crystal phases, and further includes Mn ₃ Al ₂ (SiO ₄ ) ₃ or MgAl ₂ O ₄ .

Specifically, 70.0 to 90.0 wt% of Al in terms of Al ₂ O _3, 10.0 to 30.0 wt% of Zr in terms of ZrO _2, the total of Al ₂ O ₃ and ZrO ₂ 100 If the mass%, 2.0 to 7.0 mass% of Mn in terms of MnO, 2.0 to 7.0 wt% of Si in terms of SiO _2, 0.5 to 2.0 mass Ba in terms of BaO %, Mg is preferably 0 to 2.0% by mass in terms of MgO. Thus, a low Young's modulus can be achieved while improving the bending strength.

The ceramic green body, for example, Al ₂ O ₃ powder 70.0 to 90.0 wt%, a ZrO ₂ powder 10.0 to 30.0 wt%, 2.0 to 7.0 wt% of MnO powder, Si After preparing a molded body containing 2.0 to 7.0% by mass in terms of SiO ₂ , 0.5 to 2.0% by mass of BaO powder, and 0 to 2.0% by mass of MgO powder, It is produced by firing at 1250 to 1500 ° C.

In this case, as shown in Table 1 below, for Al ₂ O ₃ , the average particle size of the raw material (Al ₂ O ₃ powder) is 0.3 to 2.5 μm, and the The crystal grain size of ₂ O ₃ is preferably 0.7 to 3.0 μm. Further, as for ZrO ₂ , the average particle size of the raw material (ZrO ₂ powder) is 0.05 to 1.0 μm, and the crystal particle size of ZrO ₂ when formed into a sintered body is 0.05 to 1.0 μm. It is preferred that

  In addition, the average particle size of the raw material is calculated based on the volume-based particle size distribution obtained by measuring with a laser diffraction scattering type particle size distribution measuring method (manufactured by HORIBA, LA-920). ) 50% particle size.

  The crystal grain size of the sintered body was determined as follows. That is, when the surface of the sintered body was imaged with a scanning electron microscope, the magnification of the scanning electron microscope was adjusted so that about 500 to 1000 crystal grains were captured in the entire image. Then, in the captured image, arbitrary 100 or more crystal grains were calculated by the average of the particle diameters converted into perfect circles using image processing software.

The MnO powder and the SiO ₂ powder are added as sintering aids as main components, and also to form a glass phase to lower the sintering temperature. BaO powder is added in order to suppress generation of MnAl ₂ O ₄ that increases hardness. MgO powder is added to produce a spinel crystal phase having characteristics such as resistance to chemical corrosion and low electrical loss, that is, MgAl ₂ O ₄ . As the electrical characteristics, the dielectric loss tangent is preferably 200 × 10 ⁻⁴ or less at 1 MHz. More preferably, it is 20 × 10 ⁻⁴ or less. Thereby, the ceramic base can be applied to the high-frequency circuit board, which is preferable. Further, the relative dielectric constant is preferably from 10 to 15.

  If necessary, Mo (molybdenum) oxide, W (tungsten) oxide, or Cr (chromium) oxide may be contained as a coloring agent in an amount of 1.0% by mass or less.

  Thereby, sintering can be performed at a low temperature of 1250 to 1500 ° C., and a ceramic body having a bending strength of 650 MPa or more and a Young's modulus of 300 GPa or less can be realized. Specifically, a ceramic base material having a bending strength of 650 MPa to 1100 MPa and a Young's modulus of 240 GPa to 300 GPa can be realized.

  Generally, the Young's modulus of a ceramic body increases as the bending strength increases. When the Young's modulus is high, it is difficult to deform and becomes brittle, so that cracks are liable to occur, and chipping at the time of chip division is liable to occur.

  However, the ceramic substrate according to the present embodiment is also suitable for a high-frequency circuit board, and has a low Young's modulus of 300 GPa or less even when the bending strength is 650 MPa or more. The ratio is small, it is difficult to break due to bending stress when mounted as a package part, etc., it is hard to generate cracks when brazing, it can improve the yield, and products using ceramic base (ceramic package, high frequency Circuit board, etc.) can be realized at low cost.

Note that by a 70.0 to 90.0 mass% Al content in terms of Al ₂ O _3, the amount of Al ₂ O ₃ which is generated becomes optimum, the firing temperature is also increased, Al ₂ It is possible to suppress an increase in the crystal grain size of O ₃ , thereby easily improving the bending strength.

By setting the content of Zr to 10.0 to 30.0% by mass in terms of ZrO ₂ , the bending strength can be easily improved, the Young's modulus can be prevented from increasing, and the dielectric constant can be increased. And a decrease in thermal conductivity can be suppressed.

  By setting the content of Mn to 2.0 to 7.0% by mass in terms of MnO, it is possible to suppress a decrease in the amount of the generated glass phase, and it is easy to achieve densification at 1250 to 1500 ° C. Further, it is possible to suppress a decrease in the softening temperature and an increase in the porosity of the produced glass. Further, a decrease in bending strength can be suppressed.

By setting the content of Si to 2.0 to 7.0% by mass in terms of SiO ₂ , a decrease in the amount of the generated glass phase can be suppressed, and densification at 1250 to 1500 ° C. can be easily achieved. In addition, it is possible to suppress a decrease in the softening temperature of the produced glass and an increase in the porosity. Further, a decrease in bending strength can be suppressed.

By setting the content of Ba to 0.5 to 2.0% by mass in terms of BaO, generation of MnAl ₂ O ₄ can be easily suppressed, and a decrease in strength can be suppressed. Further, by suppressing the sintering temperature from increasing, grain growth of alumina and zirconia can be suppressed, and a decrease in strength can be suppressed.

  By setting the content of Mg to 0 to 2.0% by mass in terms of MgO, it is possible to suppress an increase in the sintering temperature, suppress the grain growth of alumina and zirconia, and suppress a decrease in strength. .

Therefore, by including Al, Zr, Mn, Si, Ba, and Mg in the above-described ratio, the firing temperature of the porcelain can be optimized, and the strength of the generated glass phase can be increased. As a result, the bending strength , And conversely, the Young's modulus is reduced, and the miniaturization of a product (ceramic package or the like) using the ceramic base can be promoted. Moreover, it can be manufactured at a low firing temperature, which is advantageous for reducing costs. Furthermore, for example, the chipping occurrence rate in chip division by the pressing roller can be reduced, and the productivity can be improved. Electrical characteristics (dielectric loss tangent) can also be kept low. In addition, (i) adding MgO, or (ii) that there is no Mn ₃ Al ₂ (SiO ₄ ) _{3 in the} crystal phase and MgAl ₂ O ₄ exists, or if ( i ) and (ii) above, It has a low dielectric loss tangent and is preferably used, for example, for a high-frequency circuit board.

  Here, two configuration examples of the ceramic package using the ceramic body according to the present embodiment will be described with reference to FIGS.

  As shown in FIG. 1, a ceramic package according to a first configuration example (hereinafter, referred to as a first package 10A) includes a laminated substrate 12 formed of a ceramic base according to the present embodiment, and a ceramic package according to the present embodiment. And a lid 14 made of a ceramic base according to the embodiment.

  The laminated substrate 12 is configured by laminating at least a plate-shaped first substrate 16a, a plate-shaped second substrate 16b, and a frame 18 in this order. The laminated substrate 12 includes an upper electrode 20 formed on the upper surface of the second substrate 16b, a lower electrode 22 formed on the lower surface of the first substrate 16a, an inner electrode 24 formed inside, It has a first via hole 26a for electrically connecting the electrode 24 and the lower electrode 22, and a second via hole 26b for electrically connecting the inner layer electrode 24 and the upper electrode 20.

  In the first package 10A, a quartz oscillator 30 is electrically connected to an upper electrode 20 via a conductor layer 32 in an accommodation space 28 surrounded by the upper surface of the second substrate 16b and the frame 18. I have. Further, in order to protect the quartz oscillator 30, the lid 14 is hermetically sealed on the upper surface of the frame 18 via a glass layer 34.

In the first package 10A described above, an example is shown in which the crystal unit 30 is mounted in the accommodation space 28. However, even if at least one or more of a resistor, a filter, a capacitor, and a semiconductor element are mounted, Good. In the present embodiment, the dielectric loss tangent at 1 MHz is 200 × 10 ⁻⁴ or less, preferably 20 × 10 ⁻⁴ or less, and thus is suitable as a high-frequency circuit board.

  And since the laminated substrate 12 and the lid 14 constituting the first package 10A are composed of the ceramic base material according to the present embodiment, the bending strength is 650 MPa or more and the Young's modulus is 300 GPa or less. When the flexural strength is 650 MPa or less and the Young's modulus is greater than 300 GPa, as described above, it is difficult to deform and becomes brittle, so that chipping at the time of chip division is likely to occur. Further, there is a possibility that thermal stress is applied when the lid 14 is sealed or during secondary mounting, and the lid 14 is broken. Alternatively, there is a possibility that the package may be destroyed during handling or as a package component due to an impact after being mounted.

  If the bending strength is 650 MPa or more and the Young's modulus is 300 GPa or less, such a risk of destruction can be avoided. Even if the ceramic substrate is used as the laminated substrate 12 and the lid 14 of the first package 10A without polishing the surface, it is possible to prevent destruction when the lid 14 is hermetically sealed. The manufacturing cost and reliability of 10A can be improved. The “bending strength” refers to a four-point bending strength, which is a value measured at room temperature based on JISR1601 (bending test method for fine ceramics).

  Then, since the ceramic body according to the present embodiment has the above-described composition, it can be sintered at a low temperature of 1250 to 1500 ° C. Therefore, the precursor of the ceramic base (the molded body before firing), and the electrodes (upper electrode 20, lower electrode 22, inner layer electrode 24) and via hole 26 (first via hole 26a, second via hole 26b) are simultaneously fired. Thus, the laminated substrate 12 can be manufactured, and the manufacturing process can be simplified.

  Next, a method of manufacturing the ceramic base will be described with reference to FIG. 2 along a method of manufacturing the first package 10A, for example.

First, 2.0 to 7.0 mass in step S1a in Fig. 2, Al ₂ O ₃ powder 70.0 to 90.0 wt%, a ZrO ₂ powder 10.0 to 30.0 wt%, a MnO powder %, A mixed powder containing 2.0 to 7.0% by mass of Si in terms of SiO ₂ , 0.5 to 2.0% by mass of BaO powder, and 0 to 2.0% by mass of MgO powder. In S1b, an organic component (binder) is prepared, and in step S1c, a solvent is prepared.

The average particle size of the Al ₂ O ₃ powder is preferably from 0.3 to 2.5 μm. The average particle size of the ZrO ₂ powder is preferably 0.05 to 1.0 μm. This range is suitable for obtaining uniform porcelain, and can improve strength by densification and sinterability of Al ₂ O ₃ and ZrO ₂ themselves.

The average particle size of the MnO powder is preferably from 0.5 to 4.0 μm. The average particle size of the SiO ₂ powder is preferably from 0.1 to 2.5 μm. The average particle size of the BaO powder is preferably 0.5 to 4.0 µm. The average particle size of the MgO powder is preferably from 0.1 to 1.0 μm.

In these MnO powders, SiO ₂ powders, BaO powders, and MgO powders, in a preferable range, the dispersibility of the particles can be improved, the composition can be made uniform, and the strength can be improved.

  Examples of the organic component (binder) prepared in step S1b include a resin, a surfactant, and a plasticizer. Examples of the resin include polyvinyl butyral, examples of the surfactant include tertiary amines, and examples of the plasticizer include phthalic acid esters (eg, diisononyl phthalate: DINP).

  Examples of the solvent prepared in step S1c include an alcohol-based solvent and an aromatic-based solvent. Examples of the alcohol-based solvent include IPA (isopropyl alcohol), and examples of the aromatic-based solvent include toluene.

  Then, in the next step S2, after mixing and dispersing the organic component and the solvent in the above-mentioned mixed powder, in step S3, by a known molding method such as a pressing method, a doctor blade method, a rolling method, and an injection method, A ceramic molded body (also referred to as a ceramic tape) which is a precursor of a ceramic base is produced. For example, after a slurry is prepared by adding an organic component or a solvent to the mixed powder, a ceramic tape having a predetermined thickness is produced by a doctor blade method. Alternatively, an organic component is added to the mixed powder, and a ceramic tape having a predetermined thickness is produced by press molding, rolling molding, or the like.

  In step S4, the ceramic tape is cut and processed into a desired shape, a first tape having a large area for the first substrate, a second tape having a large area for the second substrate, and a third tape for the frame body. Then, a fourth tape for the lid is produced, and a through hole for forming the first via hole 26a and the second via hole 26b is formed by punching using a mold, microdrilling, laser processing, or the like.

  Next, in step S5, a conductor paste for forming the upper surface electrode 20, the lower surface electrode 22, and the inner layer electrode 24 is screen-printed, gravure-printed, or the like on the first tape and the second tape manufactured as described above. Printing and coating are performed by a method, and if necessary, a conductive paste is filled in the through holes.

The conductor paste uses, as a conductor component, at least one of refractory metals such as W (tungsten) and Mo (molybdenum), which is equivalent to Al ₂ O ₃ powder, SiO ₂ powder, or ceramic base. It is preferable that the powder is added, for example, at a ratio of 1 to 20% by mass, particularly 8% by mass or less. Thereby, the adhesion between the alumina sintered body and the conductor layer can be increased while the conduction resistance of the conductor layer is kept low, and the occurrence of defects such as chipping of the plating can be prevented.

  Then, in step S6, the first tape and the second tape on which the conductor paste is applied by printing and the third tape for the frame are aligned and laminated and pressed to produce a laminate.

  After that, in step S7, dividing grooves for chip division are formed on both surfaces of the laminate by, for example, knife cutting.

In the next step S8, the laminated body and the fourth tape are subjected to a forming gas atmosphere of hydrogen and nitrogen containing 5% or more of hydrogen, for example, a forming gas atmosphere of H ₂ / N ₂ = 30% / 70% (wetter temperature of 25 to 70%). (47 ° C.) in a temperature range of 1250 to 1500 ° C. As a result, a laminated original plate (multi-piece substrate) in which the laminate and the conductive paste are simultaneously fired is produced. As a result of this firing, as described above, the crystal phase has a main crystal phase of Al ₂ O ₃ and ZrO ₂ and, in addition, a ceramic base containing Mn ₃ Al ₂ (SiO ₄ ) ₃ or MgAl ₂ O ₄ , An individual substrate can be manufactured.

  By performing the firing atmosphere in the above-described forming gas atmosphere, oxidation of the metal in the conductor paste can be prevented. The firing temperature is preferably in the above-mentioned temperature range. Densification can be promoted, and bending strength can be improved. In addition, it is possible to reduce the variation in the shrinkage ratio of the first tape, the second tape, and the third tape that constitute the laminate, thereby improving the dimensional accuracy and the yield. Since there is no need to raise the firing temperature, there is no need to increase the cost of the equipment.

The crystal grain size of Al ₂ O ₃ when formed into a sintered body is preferably 0.7 to 3.0 μm, and the crystal grain size of ZrO ₂ when formed into a sintered body is 0.05 to 1 μm. 0.0 μm is preferable. This range is suitable for obtaining uniform porcelain, and can improve strength by densification and sinterability of Al ₂ O ₃ and ZrO ₂ themselves.

  Next, in step S9, the above-described multi-piece substrate is subjected to a plating treatment, and the conductor layer formed on the surface of the multi-piece substrate is made of Ni, Co, Cr, Au, Pd, and Cu. At least one type of plating layer is formed, and a number of upper electrodes 20 and a number of lower electrodes 22 are formed on the surface of the multi-piece substrate.

  Thereafter, in step S10, the multi-piece substrate is pressed by a pressing roller or the like to be divided into a plurality of pieces (chip division), and a plurality of laminated substrates 12 having the accommodation space 28 are manufactured. In step S11, a quartz oscillator 30 is mounted on each of the accommodation spaces 28 of the plurality of laminated substrates 12 on the upper surface electrode 20 via the conductor layer 32.

  In step S12, the upper surface of each laminated substrate 12 is hermetically sealed (lid joint) with the ceramic lid 14 on which the sealing glass layer 34 is formed, so that the quartz oscillator 30 is internally formed. Are completed, and a plurality of first packages 10A on which are mounted are completed.

In the method of manufacturing the first package 10A (the method of manufacturing the ceramic body), as described above, the crystal phase is Al ₂ O ₃ and ZrO ₂ as the main crystal phase, and the other is Mn ₃ Al ₂ (SiO ₄ ). It is also suitable for a high frequency circuit board containing ₃ or MgAl ₂ O ₄ , and can produce a ceramic base material having a bending strength of 650 MPa or more and a Young's modulus of 300 GPa or less. In addition, the chipping rate at the time of chip division is low, the yield can be improved, and the ceramic substrate (ceramic package, high-frequency circuit board, etc.) using a ceramic substrate can be miniaturized at low cost. Can be produced at a low firing temperature.

  Next, a ceramic package (hereinafter, referred to as a second package 10B) according to a second configuration example will be described with reference to FIGS.

  As shown in FIG. 3, the second package 10B has substantially the same configuration as the above-described first package 10A, but differs in the following points.

  That is, the metal lid 40 is hermetically sealed on the frame 18 of the laminated substrate 12 by using a high-temperature sealing material 42 such as silver solder.

  In addition, a bonding layer 44 is interposed between the upper surface of the frame 18 of the laminated substrate 12 and the high-temperature sealing material 42. The bonding layer 44 includes a metallized layer 46 formed of the same material as the upper surface electrode 20 on the upper surface of the frame 18, an electrolytic plating layer 48 of nickel (Ni) formed on the metallized layer 46, An electroless plating layer 50 of, for example, gold (Au) is formed on the Ni electroplating layer 48.

  The metal lid 40 is formed in a flat plate shape having a thickness of 0.05 to 0.20 mm, and is made of an iron-nickel alloy plate or an iron-nickel-cobalt alloy plate. A brazing material such as a silver-copper eutectic brazing material, which is a high-temperature sealing material 42, is formed on the lower surface (the entire surface or a portion corresponding to the frame body 18) of the metal lid 40. The thickness is about 5 to 20 μm.

  Specifically, the metal cover 40 is formed by punching a composite plate formed by rolling a brazing material foil such as silver-copper brazing on the lower surface of an iron-nickel alloy plate or an iron-nickel-cobalt alloy plate. It is manufactured by punching into a predetermined shape with a mold.

  As the high-temperature sealing material 42, brazing material 1 (85Ag-15Cu), brazing material 2 (72Ag-28Cu), brazing material 3 (67Ag-29Cu-4Sn) shown in Table 2 below can be used.

  The Ni electrolytic plating layer 48 and the Au electroless plating layer 50 function as layers for improving the wettability of the high-temperature sealing material 42 with respect to the metallized layer 46.

  Next, a method for manufacturing the second package 10B will be described with reference to FIG. Note that the description of the steps overlapping with FIG. 2 will be omitted.

  First, in step S101 in FIG. 4, a mixed powder, an organic component, and a solvent for preparing a ceramic tape are prepared. The prepared mixed powder, organic component, and solvent are the same as those in Steps S1a, S1b, and S1c described above, and thus redundant description will be omitted.

  Then, in step S102, the organic component and the solvent are mixed and dispersed in the above-mentioned mixed powder, and in step S103, the ceramic substrate is formed by a known molding method such as a pressing method, a doctor blade method, a rolling method, and an injection method. To produce a ceramic molded body (ceramic tape) which is a precursor of the above.

  In step S104, the ceramic tape is cut and processed into a desired shape, and a first tape having a large area for the first substrate 16a, a second tape having a large area for the second substrate 16b, and a tape for the frame 18 are formed. A third tape is manufactured, and a through hole for forming the first via hole 26a and the second via hole 26b is formed by microdrilling, laser processing, or the like.

On the other hand, in step S105, a raw material powder for the conductive paste, an organic component, and a solvent are prepared. The raw material powder to be prepared is, as described above, at least one of metal powders such as W (tungsten), Mo (molybdenum), nickel (Ni), and, optionally, Al ₂ O ₃ powder or SiO ₂ powder, Alternatively, a mixed powder to which a powder equivalent to that of the ceramic base is added, for example, at a ratio of 1 to 20% by mass, particularly 8% by mass or less may be mentioned. The organic component to be prepared includes a resin (for example, ethyl cellulose), a surfactant and the like. The prepared solvent includes terpineol and the like.

  Then, in step S106, an organic component and a solvent are mixed and dispersed in the above-mentioned mixed powder to prepare a conductor paste.

  Next, in step S107, the first to third tapes manufactured as described above are printed and applied with a conductive paste by a method such as screen printing or gravure printing.

  After that, in step S108, the first to third tapes on which the conductor paste is applied by printing are aligned, laminated and pressed to produce a laminate.

  Thereafter, in step S109, division grooves for chip division are formed on both surfaces of the laminate by, for example, knife cutting.

In the next step S110, the laminate is fired in a forming gas atmosphere of H ₂ / N ₂ = 30% / 70% (wetter temperature 25 to 47 ° C.) in a temperature range of 1250 to 1500 ° C. As a result, a laminated original plate (multi-piece substrate) in which the laminate and the conductive paste are simultaneously fired is produced. This multi-cavity substrate has a shape in which the shapes of many frame bodies 18 are arranged integrally. In addition, by this firing, the conductive paste becomes an electrode (such as the upper surface electrode 20) or the metallized layer 46.

  In the next step S111, at least the surface of the metallized layer 46 is washed with an alkali, an acid or the like (pretreatment). That is, acid cleaning is performed after alkali cleaning. In the pretreatment, the alkali and the acid may be used after being diluted to an appropriate concentration. In addition, the pretreatment is performed at a temperature of about 20 ° C. to 70 ° C. and for several minutes to tens of minutes.

  In step S112, Ni plating or electroless plating is performed to form a Ni plating layer 48 (film thickness: 1.0 to 5.0 μm) on the metallized layer 46.

  In step S113, an electrolytic or electroless Au plating layer 50 (thickness: 0.05 to 0.3 μm) is formed on the Ni plating layer 48.

  Then, in step S114, the multi-piece substrate is divided into a plurality of chips (chip division) by pressing with a pressing roller or the like, and a plurality of laminated substrates 12 each having the accommodation space 28 is manufactured. Thereafter, in step S115, the crystal oscillator 30 is mounted on each of the accommodation spaces 28 of the plurality of laminated substrates 12 on the upper surface electrode 20 via the conductor layer 32.

Then, in step S116, the metal lid 40 having the high-temperature sealing material 42 formed on the back surface is placed on the frame 18 with the high-temperature sealing material 42 and the upper surface (bonding layer 44) of the frame 18 facing each other. Cover. Thereafter, a pair of roller electrodes of the seam welding machine are rolled while being brought into contact with the opposed outer peripheral edges of the metal lid 40, and a part of the high-temperature sealing material 42 is made to flow by applying a current between the roller electrodes. The metal lid 40 is hermetically sealed on the frame 18 by melting. The atmosphere at the time of sealing is performed in N ₂ gas or vacuum. Thereby, a plurality of second packages 10B in which the crystal unit 30 is mounted are completed.

For Examples 1-12, Comparative Examples 1 and 2, Al ₂ O ₃ and ZrO ₂ non crystal phase of the ceramic matrix, the mechanical properties (flexural strength (bending strength) and Young's modulus), electrical properties (dielectric constant and Dielectric tangent) was confirmed.

(Example 1)
Raw material powder was prepared. The raw material powders were Al ₂ O ₃ powder having an average particle size of 1.70 μm, ZrO ₂ powder having an average particle size of 0.50 μm, MnO powder having an average particle size of 1.0 μm, SiO ₂ powder having an average particle size of 1.0 μm, and It is a BaO powder having a particle size of 1.0 μm.

The raw material powders are shown in Table 3 below (Al ₂ O ₃ powder: 78.60% by mass, ZrO ₂ powder: 21.40% by mass, MnO powder: 3.04% by mass, SiO ₂ powder: 2.78% by mass) , BaO powder: 0.77% by mass to obtain a mixed powder, and the obtained mixed powder was mixed with polyvinyl butyral, a tertiary amine, and a phthalic ester (diisononyl phthalate: DINP) as organic components. A slurry was prepared by mixing and diffusing IPA (isopropyl alcohol) and toluene as a solvent, and then preparing a ceramic tape having a thickness of 60 to 270 μm by a doctor blade method. (The maximum temperature) was 1440 ° C., and the mixture was fired in a forming gas atmosphere of H ₂ + N ₂ to produce a ceramic body according to Example 1. The conductors were fired simultaneously. The first ceramic body for confirming the crystal phase, the second ceramic body for confirming the bending strength, the third ceramic body for confirming the Young's modulus, and the electrical characteristics ( A fourth ceramic body for measuring the relative dielectric constant and the dielectric loss tangent was prepared. The same applies to Examples 2 to 12 and Comparative Examples 1 and 2 described below.

(Example 2)
Among the raw material powders, the above-described procedure was performed except that the MnO powder was 2.81% by mass, the SiO ₂ powder was 2.57% by mass, the BaO powder was 0.71% by mass, and the MgO powder was 0.54% by mass. A ceramic body according to Example 2 was produced in the same manner as in Example 1.

(Example 3)
A ceramic body according to Example 3 was produced in the same manner as in Example 2 except that the raw material powder was changed to 89.30% by mass of Al ₂ O ₃ powder and 10.70% by mass of ZrO ₂ powder. did.

(Example 4)
Among the raw material powders, the above-described procedure was performed except that the MnO powder was 3.34% by mass, the SiO ₂ powder was 2.04% by mass, the BaO powder was 0.71% by mass, and the MgO powder was 0.54% by mass. In the same manner as in Example 1, a ceramic substrate according to Example 4 was produced.

(Example 5)
Among the raw material powders, the above-described operation was performed except that the MnO powder was 2.27% by mass, the SiO ₂ powder was 3.11% by mass, the BaO powder was 0.71% by mass, and the MgO powder was 0.54% by mass. A ceramic body according to Example 5 was produced in the same manner as in Example 1.

(Example 6)
Among the raw material powders, the above-described process was performed except that the MnO powder was 2.44% by mass, the SiO ₂ powder was 2.23% by mass, the BaO powder was 1.42% by mass, and the MgO powder was 0.54% by mass. A ceramic body according to Example 6 was produced in the same manner as in Example 1.

(Example 7)
Among the raw material powders, 2.57% by mass of MnO powder, 2.35% by mass of SiO ₂ powder, 0.64% by mass of BaO powder, and 1.07% by mass of MgO powder, and the firing temperature (maximum temperature) ) Was changed to 1470 ° C., and a ceramic body according to Example 7 was produced in the same manner as in Example 1 described above.

(Example 8)
Of the raw material powders, 4.36% by mass of MnO powder, 4.00% by mass of SiO ₂ powder, 1.11% by mass of BaO powder, and 0.83% by mass of MgO powder, and the firing temperature (maximum temperature) ) Was changed to 1390 ° C., and a ceramic body according to Example 8 was produced in the same manner as in Example 1 described above.

(Example 9)
A ceramic body according to Example 9 was produced in the same manner as in Example 8 except that among the raw material powders, Al ₂ O ₃ powder was 70.00% by mass and ZrO ₂ powder was 30.00% by mass. did.

(Example 10)
Among the raw material powders, the ceramic substrate according to Example 10 was manufactured in the same manner as in Example 2 except that the average particle size of the Al ₂ O ₃ powder was 0.50 μm and the firing temperature (maximum temperature) was 1390 ° C. Was prepared.

(Example 11)
Of the raw material powders, 6.04% by mass of MnO powder, 5.53% by mass of SiO ₂ powder, 1.53% by mass of BaO powder, 1.15% by mass of MgO powder, and the firing temperature (maximum temperature) ) Was changed to 1310 ° C., except that the ceramic substrate of Example 11 was produced in the same manner as in Example 10 described above.

(Example 12)
A ceramic body according to Example 12 was prepared in the same manner as in Example 10 except that among the raw material powders, Al ₂ O ₃ powder was 70.00% by mass and ZrO ₂ powder was 30.00% by mass. did.

(Comparative Example 1)
Of the raw material powders, 75.80% by mass of Al ₂ O ₃ powder, 24.20% by mass of ZrO ₂ powder, 0.00% by mass of MnO powder (without addition), and 0.60% by mass of SiO ₂ powder In the same manner as in Example 1 except that the amount of BaO powder was 0.00% by mass (not added), the amount of MgO powder was 0.10% by mass, and the firing temperature (maximum temperature) was 1500 ° C. A ceramic body according to Comparative Example 1 was produced.

(Comparative Example 2)
Comparative Example 1 was the same as Comparative Example 1 except that the raw material powder was changed to 80.00% by mass of Al ₂ O ₃ powder and 20.00% by mass of ZrO ₂ powder and the firing temperature (maximum temperature) was 1580 ° C. Similarly, a ceramic body according to Comparative Example 2 was produced.

(Evaluation)
<Confirmation of crystal phase>
Each of the first ceramic bodies of Examples 1 to 12 and Comparative Examples 1 and 2 was identified by X-ray diffraction. As a criterion for determining whether or not a crystal phase was contained, the main peak intensity was 3% or more of the intensity of the main peak (104 plane) of alumina. That is, the crystal phase contained was confirmed based on the position (peak position) of the main peak intensity of 3% or more of the main peak intensity of alumina, the Miller index, the lattice constant, and the like.

<Bending strength>
Each second ceramic body of Examples 1 to 12 and Comparative Examples 1 and 2 was measured at room temperature based on a four-point bending strength test of JISR1601.

<Young's modulus>
The third ceramic bodies of Examples 1 to 12 and Comparative Examples 1 and 2 were measured at room temperature based on the static elastic modulus test method of JISR1602.

<Relative permittivity>
The fourth ceramic bodies of Examples 1 to 12 and Comparative Examples 1 and 2 were measured at a frequency of 1 MHz at room temperature by the capacitance method of JISC2138.

<Dielectric loss tangent>
The fourth ceramic bodies of Examples 1 to 12 and Comparative Examples 1 and 2 were measured at a frequency of 1 MHz at room temperature by the capacitance method of JISC2138.

  The details of Examples 1 to 12 and Comparative Examples 1 and 2 are shown in Table 3, and the evaluation results are shown in Table 4. In Table 4, the relative permittivity of the electrical characteristics is described as “εr”, and the dielectric loss tangent is described as “tan δ”.

In all of Examples 1 to 12, the bending strength (flexural strength) was 650 MPa or more, and the Young's modulus was 300 GPa or less. The crystal grain size of Al ₂ O ₃ of the sintered body was 0.7 to 3.0 μm, and the crystal grain size of ZrO ₂ was 0.05 to 1.0 μm.

In Example 1, except for Al ₂ O ₃ and ZrO ₂ as the crystal phase, only Mn ₃ Al ₂ (SiO ₄ ) ₃ was observed. In that regard, the electrical properties, particularly the dielectric loss tangent, were 170, which was worse than the other Examples 2 to 12. Regarding the mechanical properties, the bending strength was as high as 720 MPa and the Young's modulus was as low as 268 GPa, and good results were obtained.

  In Example 12, the bending strength of the mechanical properties was 1030 MPa, which was the best result among Examples 1 to 12. In Example 9, the Young's modulus of the mechanical properties was 249 GPa, which was the best result among Examples 1 to 12. In Examples 3 and 10, the dielectric loss tangent of the electrical characteristics was 17 and 15, which was the best result among Examples 1 to 12.

  In Examples 2, 4 to 8, and 11, the bending strength range of the mechanical properties was 700 to 910 MPa, and the Young's modulus range of the mechanical properties was 255 to 300 GPa, which was a good result. The range of the dielectric loss tangent of the electric characteristics was also 20 to 40, which was a good result.

In Example 6, MgAl ₂ O ₄ and BaAl ₂ Si ₂ O ₈ were observed except for the crystal phases other than Al ₂ O ₃ and ZrO ₂ .

On the other hand, in Comparative Examples 1 and 2, no crystal phases other than Al ₂ O ₃ and ZrO ₂ were observed. Regarding the mechanical properties, the flexural strength of Comparative Example 1 was 970 MPa, which was higher than that of Example 10, but the Young's modulus was as high as 336 GPa. Regarding Comparative Example 2, the Young's modulus was as high as 324 GPa even though the bending strength was 650 MPa, which was lower than that of Example 1.

  The ceramic substrate and the method for manufacturing the same according to the present invention are not limited to the above-described embodiment, but may employ various configurations without departing from the gist of the present invention.

Claims (7)

The crystal phase has Al ₂ O ₃ and ZrO ₂ as main crystal phases, and further includes Mn ₃ Al ₂ (SiO ₄ ) ₃ or MgAl ₂ O ₄ ,
A ceramic body having a bending strength of 650 MPa or more and a Young's modulus of 300 GPa or less. The ceramic body according to claim 1,
A ceramic body having a flexural strength of 650 MPa or more and 1100 MPa or less and a Young's modulus of 240 GPa or more and 300 GPa or less. The ceramic body according to claim 1,
A ceramic body having a dielectric loss tangent of 1 × 10 ⁻⁴ or less at 1 MHz and a relative dielectric constant of 10 to 15. The ceramic body according to claim 1,
70.0 to 90.0 wt% of Al in terms _{of Al} 2 _{O 3,} 10.0 to 30.0 wt% of Zr in terms of ZrO _2, when the sum of the _Al 2 _{O 3} and ZrO ₂ is 100 mass% , Mn is 2.0 to 7.0% by mass in terms of MnO, Si is 2.0 to 7.0% by mass in terms of SiO ₂ , Ba is 0.5 to 2.0% by mass in terms of BaO, and Mg is MgO. A ceramic body containing 0 to 2.0% by mass in conversion. 70.0 to 90.0 wt% of Al in terms _{of Al} 2 _{O 3,} 10.0 to 30.0 wt% of Zr in terms of ZrO _2, when the sum of the _Al 2 _{O 3} and ZrO ₂ is 100 mass% , Mn is 2.0 to 7.0% by mass in terms of MnO, Si is 2.0 to 7.0% by mass in terms of SiO ₂ , Ba is 0.5 to 2.0% by mass in terms of BaO, and Mg is MgO. A molded body producing step of producing a molded body containing 0 to 2.0% by mass in conversion;
And baking the molded body at 1250 to 1500 ° C. The method for producing a ceramic body according to claim 5 ,
After the molded body forming step, the molded body further includes a step of forming a conductor layer containing a metal,
In the firing step, a method for manufacturing a ceramic body includes firing the formed body on which the conductor layer is formed. The method for producing a ceramic body according to claim 5 ,
The method according to claim 1, wherein the firing step is performed in a forming gas of hydrogen and nitrogen containing 5% or more of hydrogen.

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