JP3898489B2 - Manufacturing method of multilayer wiring board - Google Patents

Description

【００６１】
表１から明らかなように、ガラスセラミックグリーンシートおよび拘束用グリーンシートに同一の着色剤を含有させた試料Ｎｏ．１〜３、５〜１０では、ガラスセラミック配線基板の表層の厚みが１８０±５μｍとなり表層厚みを設計値に近づけることができた。
【００６２】
これに対して、ガラスセラミックグリーンシートには着色剤を添加したものの、拘束用グリーンシートには着色剤を添加しなかった試料Ｎｏ．４、１１では、ガラスセラミック配線基板表層の着色剤が拘束用シート側へ拡散したためガラスセラミック基板表層の色調が白っぽくなり基板自体の本来の色調が現れるまで拘束用シートのセラミック粉末を完全に除去しようと基板表面を多く削ったところ基板表面の１層の厚みが設計値よりも大幅に薄くなった。
【００６３】
【発明の効果】
以上詳述したとおり、本発明によれば、ガラスセラミックグリーンシートおよび拘束用グリーンシート中に同一の着色剤を含有することにより、焼成後に、拘束用シートとガラスセラミック配線基板との界面近傍において着色剤の濃度分布による色調の分布がないことから、ガラスセラミック配線基板の表面から拘束用シートのセラミック粉末を除去する際に基板の色調の変動を気にすることなく拘束用シートの除去条件を決めることができ、このため拘束用シート除去による基板表面の１層の厚み変動を抑制できることから寸法精度の高い多層配線基板を得ることができる。
【図面の簡単な説明】
【図１】本発明の多層配線基板の製造方法を説明するための工程図である。
【図２】本発明の多層配線基板の製造に用いる転写シートを作製する工程図である。
【図３】本発明の多層配線基板の製造方法によって得られる多層配線基板の概略断面図である。
【符号の説明】
１ ガラスセラミックグリーンシート
３ 拘束用グリーンシート
７ 配線回路層
２１ 積層体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a multilayer wiring board suitable for a multilayer wiring board, a package for housing semiconductor elements, and the like.
[0002]
[Prior art]
Conventionally, a multilayer ceramic wiring board capable of relatively high density wiring is widely used as a wiring board, for example, a multilayer wiring board used for a package for housing a semiconductor element. This multilayer ceramic wiring board is composed of an insulating substrate such as alumina or glass ceramic and a wiring conductor made of metal such as W, Mo, Cu, or Ag formed on the surface thereof. A cavity is formed in the part, a semiconductor element is accommodated in the cavity, and the cavity is hermetically sealed by a lid.
[0003]
In recent years, in a wiring board applied to a package for housing a semiconductor element in which semiconductor elements such as IC and LSI, which have been highly integrated, are mounted, and a hybrid integrated circuit device in which various electronic components are mounted, the density and There is a demand for resistance and reduction in size and weight, and a low dielectric constant is obtained compared to alumina-based ceramic materials, and a low-resistance metal such as Cu can be used as a wiring circuit layer. The so-called glass-ceramic wiring board has attracted more attention.
[0004]
As a method of forming such a glass ceramic wiring substrate, a conductor paste mainly composed of a metal powder such as Cu, Ag, etc. is formed on a glass ceramic green sheet by a screen printing method or the like, and after laminating a plurality of sheets, A method of firing at a temperature below the melting point of the conductor is common.
[0005]
However, glass ceramic green sheets shrink about 10 to 20% in the X, Y, and Z directions during firing, respectively, and it is difficult to control the shrinkage rate. Usually fluctuates about ± 0.5%.
[0006]
As a technique for reducing the dimensional variation in the XY direction, the following methods are disclosed, for example, Japanese Patent Laid-Open Nos. 4-243978, 5-28867, 5-102666, and In Japanese Patent Laid-Open No. 10-200261, etc., a constraining green sheet that is not sintered at the firing temperature of the glass ceramic green sheet is laminated on the upper and lower surfaces of the laminate formed of the glass ceramic green sheet and fired. The sheet suppresses firing shrinkage in the XY direction. And the method of removing the green sheet for restraint by rubbing with a brush etc. after baking or ultrasonic cleaning is proposed.
[0007]
Further, among the above publications, JP-A-5-28867 and JP-A-10-200221 remove the constraining sheet after firing by adding a colorant to either the glass ceramic green sheet or the constraining green sheet. The method by which the standard of this can be judged visually is described.
[0008]
[Problems to be solved by the invention]
However, in the method for producing a multilayer wiring board disclosed in the above publication, for example, when a colorant is contained in a glass ceramic green sheet, Al used for a restraining sheet is used.₂O_ThreeAnd ZrO₂White ceramic powder adheres to the surface of the fired glass-ceramic wiring board, and the colorant component dissolved in the glass in the glass-ceramic material diffuses to the restraining sheet side to restrain the glass-ceramic wiring board. In the vicinity of the interface with the sheet, a color tone distribution due to the concentration distribution of the colorant component occurs. For this reason, if it is attempted to completely remove the ceramic powder of the restraining sheet until the original color tone of the glass ceramic wiring board itself appears, it is necessary to scrape the substrate surface, and the thickness of one layer of the substrate surface tends to fluctuate in a thin direction. Become.
[0009]
On the other hand, even when a colorant is included in the restraint sheet, the colorant diffuses from the restraint sheet side to the glass-ceramic wiring board side exhibiting a white system, and the vicinity of the substrate surface is colored. As with the case where a colorant is included on the wiring board side, it is necessary to cut the substrate surface until the original color tone of the glass ceramic material appears, so the thickness of one layer on the substrate surface tends to fluctuate in the thinner direction. In some cases, the thickness of the outermost wiring circuit layer becomes thin and the sheet resistance changes.
[0010]
Therefore, an object of this invention is to provide the manufacturing method of the multilayer wiring board which can suppress the thickness fluctuation of a surface layer even after removing the sheet | seat for restraint.
[0011]
[Means for Solving the Problems]
  In the method for producing a multilayer wiring board of the present invention, a conductive wiring circuit layer is formed on the surface of a glass ceramic green sheet containing glass powder, an inorganic filler powder, and an organic binder, and then a plurality of the glass ceramic green sheets are laminated. Forming a laminate, and laminating and laminating constraining green sheets that can maintain porosity at the firing temperature of the glass ceramic green sheet on the upper and lower surfaces of the laminate,conductorIn a method for manufacturing a multilayer wiring board that is fired while suppressing shrinkage in a planar direction at a temperature equal to or lower than the melting point of the wiring circuit layer, the restraining green sheet contains ceramic powder and glass powder.BothIn addition, the glass ceramic green sheet and the restraining green sheet contain the same colorant.TetanariThe glass ceramic green sheet is chromium oxide (Cr) as the colorant with respect to a total of 100% by mass of the glass powder and the inorganic filler powder.₂O_Three )0.3 qualityContaining amount%As well asThe restraining green sheet is the ceramic powder and the glass powder.Sum ofFor 100% by mass, chromium oxide (Cr₂O_Three )Contains 0.1-0.6% by massOr the glass ceramic green sheet contains 0.4% by mass of cobalt oxide (CoO) as the colorant with respect to a total of 100% by mass of the glass powder and the inorganic filler powder, and the constraint green The sheet contains 0.5% by mass of cobalt oxide (CoO) as the colorant with respect to 100% by mass in total of the ceramic powder and the glass powder.It is characterized by that.
[0012]
According to such a configuration, since there is no color tone distribution due to the concentration distribution of the colorant in the vicinity of the interface between the restraining sheet and the glass ceramic wiring board after firing, the ceramic of the restraining sheet from the surface of the glass ceramic wiring board. The removal condition of the restraining sheet can be determined without worrying about the fluctuation of the color tone of the substrate when removing the powder, and therefore, the thickness fluctuation of one layer on the substrate surface due to the removal of the restraining sheet can be suppressed.
[0013]
  In the method for manufacturing a multilayer wiring board, the constraining green sheet may contain glass powder.is important. By including glass powder in the constraining green sheet, sintering of the constraining sheet can proceed even at a temperature at which the glass ceramic wiring board is fired.
[0014]
In the manufacturing method of the multilayer wiring board, it is desirable that the colorant content in the constraining green sheet is the same as or greater than the colorant content in the glass ceramic green sheet.
[0015]
By making the amount of the colorant on the restraining sheet side that hardly sinters when firing to the glass ceramic wiring board the same or larger, it is possible to reduce the color tone difference with the glass ceramic wiring board that becomes darker when sintered. .
[0016]
In the manufacturing method of the said multilayer wiring board, it is desirable that colorant content is 0.2-5.0 mass% in the inorganic component in the green sheet for restraint. By setting the colorant content in such a range, the restraint sheet can be colored, and the sinterability of the restraint sheet and the firing shrinkage of the glass ceramic wiring board in the XY direction can be suppressed.
[0017]
  In the method for manufacturing a multilayer wiring board, the colorant is chromium oxide.OrCobalt oxideInThere isis important. If the colorant is the above metal oxide, chromium oxide can be green and cobalt oxide can be clearly colored blue, and the sinterability and restraint of the restraint sheet and the sinterability of the glass ceramic wiring board And the effects on mechanical and electrical characteristics can be reduced.
[0018]
In the manufacturing method of the multilayer wiring board, if the firing shrinkage of the restraining green sheet is 0.05 to 0.5%, the restraining sheet itself can be increased in strength and air permeability can be secured. Can be prevented and good binder removal property can be maintained.
[0019]
In the method for manufacturing a multilayer wiring board, the wiring circuit layer is preferably a copper foil. By using copper foil as the wiring circuit layer, fine and highly conductive wiring can be easily formed even in simultaneous firing with glass ceramic.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the manufacturing method of the glass ceramic wiring board which is one of the multilayer wiring boards of this invention is demonstrated.
[0021]
In the method for producing a glass ceramic wiring board of the present invention, first, as a starting material, glass powder having an average particle diameter of 0.5 to 10 μm, particularly 1 to 5 μm, and an average particle diameter of 0.5 to 10 μm, particularly an average particle diameter of 1 to A 5 μm inorganic filler powder and a colorant powder having an average particle size of 0.1 to 2 μm, particularly an average particle size of 0.2 to 1 μm are prepared.
[0022]
The glass powder used is at least SiO as a glass component.₂Including Al₂O_Three, B₂O_Three, ZnO, PbO, alkaline earth metal oxides, alkali metal oxides containing at least one kind, for example, SiO₂-B₂O_ThreeSystem, SiO₂-B₂O_Three-Al₂O_ThreeExamples thereof include borosilicate glass such as -MO type (where M represents Ca, Sr, Mg, Ba or Zn), alkali silicate glass, Ba type glass, Pb type glass, Bi type glass and the like.
[0023]
These glasses are amorphous glass by firing treatment, and by firing treatment, alkali metal silicate, quartz, cristobalite, cordierite, mullite, enstatite, anorsite, serdian, spinel, garnite, diopside , Ilmenite, willemite, dolomite, petalite and crystals of substituted derivatives thereof which precipitate at least one kind are used.
[0024]
In addition, as inorganic filler powder, quartz, cristobalite and other SiO₂Al₂O_Three, ZrO₂, Mullite, forsterite, enstatite, spinel, magnesia and ZnO are preferably used.
[0025]
In particular, the glass powder and the inorganic filler powder are mixed in a proportion of 10 to 90% by mass, particularly 40 to 80% by mass, and 10 to 90% by mass, particularly 20 to 60% by mass, of the ceramic filler component. Considering the binder removal property and sintering property of the glass ceramic green sheet, the amount of the glass component is preferably 40 to 80% by mass.
[0026]
Furthermore, chromium oxide (Cr₂O_Three), Cobalt oxide (Co_ThreeO_Four, CoO) is preferably added in an amount of 0.2 to 5.0% by mass with respect to a total of 100% by mass of the glass powder and the inorganic filler powder (inorganic component). Chromium oxide has the effect of coloring green and cobalt oxide is colored blue, and the recognition of the conductor pattern by an automatic machine can be enhanced. Iron oxide, manganese dioxide, and the like are effective as a colorant, but chromium oxide and cobalt oxide are preferable because the dielectric loss tangent of the glass ceramic material is hardly changed by the addition of the colorant. The addition amount is particularly preferably 0.3 to 1.0% by mass because the increase in dielectric loss tangent is small.
[0027]
The restraining sheet is composed of a hardly sinterable ceramic that does not substantially shrink even when fired in order to enhance the restraining property of the glass ceramic green sheet, but the restraining green sheet preferably also contains glass powder. The glass powder preferably has the same composition as the glass powder used for the glass ceramic green sheet. About glass content, although it depends on the composition of the glass ceramic material and the composition of the restraint sheet, it is a glass content with a firing shrinkage of 0.05 to 0.5% when fired with the restraint green sheet alone. Desirably, if the firing shrinkage rate is within this range, the shrinkage rate in the XY direction of the glass ceramic wiring board can be controlled with high accuracy.
[0028]
And, if the firing shrinkage rate is less than 0.05%, the restraint sheet itself is low in strength, so that the restraint sheet is easily peeled off locally when firing on a large substrate, and ceramic powder or glass powder during handling after firing. On the other hand, when the firing shrinkage ratio is larger than 0.5%, the sintering of the restraining sheet is excessively advanced, so that the effect of increasing the dimensional accuracy is poor and the air permeability is lowered, and the binder is removed. It becomes difficult to remove the restraining sheet after firing. From such a point, it is more desirable that the appropriate amount of glass powder contained in the constraining green sheet is such that the firing shrinkage of the constraining sheet is 0.1 to 0.3%.
[0029]
As described above, since the restraining sheet hardly shrinks during firing, even if the colorant content is the same as that of the glass ceramic green sheet, the color tone tends to be lighter than that of the glass ceramic material after firing. Therefore, when the amount of the colorant in the constraining green sheet is small, the same color tone distribution as when no colorant is added is likely to occur. Therefore, the content of the colorant in the constraining green sheet is desirably larger than the content in the glass ceramic green sheet.
[0030]
Next, the manufacturing method of the glass ceramic wiring board of this invention is demonstrated based on the process drawing of FIG.
[0031]
First, as shown to Fig.1 (a), said glass ceramic green sheet 1 adds an organic binder, a plasticizer, etc. with respect to the composition for the above-mentioned glass ceramic, Doctor blade method, rolling method, It is formed into a sheet having a thickness of about 50 to 500 μm by a forming method such as a press method. On the other hand, although not shown, the constraining green sheet is also formed using the same molding method as the glass ceramic green sheet.
[0032]
As the organic binder, it is desirable to use a methacrylic resin from the viewpoint of binder removal, and specific examples include i-BMA (isobutyl methacrylate), n-BMA (normal butyl methacrylate), MMA (methyl methacrylate) and the like. Of these, i-BMA is the most desirable.
[0033]
Next, as shown in FIG. 1B, a through-hole having a diameter of 50 to 200 μm is formed in the glass ceramic green sheet 1 by using a processing method such as laser, micro drill, punching, etc., and the inside is filled with a conductive paste. Thus, the via-hole conductor 5 is formed.
[0034]
The conductive paste is formed by mixing a metal component such as Cu or Ag with an organic binder such as an organic binder made of acrylic resin or terpineol. In addition, you may add a glass component etc. in this conductor paste.
[0035]
Next, as shown in FIGS. 1C and 1D, the wiring circuit layer 7 is formed on the surface of the glass ceramic green sheet 1. The wiring circuit layer 7 can also be formed by a printing method or the like using a conductive paste containing the metal conductor powder for forming the via-hole conductor 5 described above, and in particular, the width of the wiring circuit layer 7 is 75 μm or less. In particular, it is desirable to use a metal foil in order to make a fine wiring of 50 μm or less and the wiring circuit layer 7 pitch of 100 μm or less, particularly 75 μm or less. The metal foil should be made of at least one high-purity metal selected from the group consisting of Cu, Ag, Al, Au, Ni, Pt, and Pd, particularly with a purity of 99.5% by mass or more in consideration of low resistance. However, Cu foil is particularly preferable in terms of resistance and cost. In order to prevent delamination between the substrate layers after firing, the thickness of the metal foil is desirably 30 μm or less. In order to improve the adhesion to the glass ceramic green sheet, the surface roughness of at least one of the metal foils is most preferably 0.6 μm or more, particularly 2 μm or more in terms of Rz.
[0036]
For the wiring circuit layer 7 made of such a metal foil, a method of forming a desired circuit by a known photo-etching method or the like after the metal foil is bonded to the surface of the glass ceramic green sheet 1 is known. In such a method, the glass ceramic green sheet 1 is altered by the etching solution, so that it is desirable to form the glass ceramic green sheet 1 by a transfer method.
[0037]
As shown in FIG. 2, the wiring circuit layer 7 used in the transfer method has a resist 15 on the surface of the metal foil 13 after bonding a high-purity metal conductor, particularly the metal foil 13, onto a transfer film 11 made of a polymer material. Is formed by performing an etching process and removing the resist 15.
[0038]
Then, as shown in FIG. 1C, the transfer film 11 on which the wiring circuit layer 7 is formed is aligned with the surface of the glass ceramic green sheet 1 on which the via-hole conductor 5 is formed, and is laminated and pressure-bonded. 1 unit green sheet 1a as shown in FIG. 1 (d) having wiring circuit layer 7 connected to via-hole conductor 5 can be formed.
[0039]
Thereafter, as shown in FIG. 1 (e), a plurality of green sheets 1a to 1d obtained in the same manner are laminated and pressure-bonded to form a laminate. For the lamination of the green sheets 1a to 1d, a method of applying heat and pressure to the stacked green sheets 1a to 1d and thermocompression bonding, an adhesive composed of an organic binder, a plasticizer, a solvent, and the like is provided between the green sheets 1a to 1d. It is possible to adopt a method such as applying to thermocompression bonding.
[0040]
Next, as shown in FIG. 1 (f), in order to suppress the shrinkage in the planar direction, for restraint mainly composed of a ceramic material that is hardly sinterable at the firing temperature of the laminate 21 composed of the green sheets 1a to 1d. The green sheet 3 is pressure laminated on both sides of the laminate 21. In this case, the green sheets 1a to 1d and the constraining green sheet 3 can be laminated simultaneously.
[0041]
Here, the thickness of the restraining green sheet 3 laminated on the laminate of the green sheets 1a to 1d increases the restraining force of the laminate 21, facilitates the volatilization of organic components, and is formed after firing. In view of the removability of the restraining sheet from the sheet, it is preferably 10 to 200% with respect to the thickness of the laminated body 21 of the green sheets 1a to 1d. In particular, 20 to 100% is desirable because it can be suppressed. The thickness of the constraining green sheet 3 refers to the thickness of the constraining green sheet 3 laminated on the surface on one side.
[0042]
Next, as shown in FIG.1 (g), the glass-ceramic green sheet 1 is carried out by heat-processing the laminated body 21 pinched with the said restraining green sheet 3 at 100-850 degreeC, especially 400-750 degreeC. The organic component contained in the constraining green sheet 3 and the conductor paste embedded in the through hole is decomposed and removed, and then the laminate 21 and the laminate 21 are formed at a temperature of 800 to 1100 ° C., particularly 800 to 1000 ° C. By simultaneously firing the holding green sheet 3 for holding, a glass ceramic wiring board 23 that is fired and shrunk in the Z direction but suppressed in the XY direction is produced. At this time, restraint sheets 25 formed by firing are bonded to the upper and lower surfaces of the glass ceramic wiring board 23.
[0043]
When using an easily oxidizable conductor such as a Cu conductor as the wiring circuit layer 7, the firing atmosphere must be performed in an atmosphere such as nitrogen containing water vapor, and when using a hardly oxidizable conductor such as an Ag conductor as the wiring circuit layer 7. The firing atmosphere can be performed in an oxidizing atmosphere such as in the air. If the cooling rate after firing in this firing is too fast, cracks are generated due to the temperature difference and thermal expansion difference between the glass ceramic wiring board 23, the wiring circuit layer 7, and the restraining sheet 25, so the cooling rate is 400 ° C. / Hr or less is desirable. Further, a load may be applied by placing a weight on the upper surface of the laminate in order to prevent warping during firing. The load at that time is suitably 50 Pa to 1 MPa.
[0044]
Thereafter, the restraining sheet 25 bonded to the upper and lower surfaces of the glass ceramic wiring board 23 is removed by ultrasonic cleaning, polishing, water jet, chemical blasting, sand blasting, wet blasting, drive blasting or the like. According to the method for producing a multilayer wiring board of the present invention, since the same colorant is contained in both the glass ceramic wiring board 23 and the restraining sheet 25, even if both layers are co-fired and bonded, the interface Variation in color tone in the vicinity is suppressed.
[0045]
For this reason, as compared with the conventional multilayer wiring board manufacturing method in which only one of the glass ceramic wiring board 23 and the restraining sheet 25 contains a colorant so that the vicinity of the interface can be easily determined visually, Since the diffusion of the colorant from the glass ceramic wiring board 23 or the restraining sheet 25 is suppressed, the color tone of the glass ceramic wiring board 23 is removed when the ceramic powder of the restraining sheet 25 is removed from the surface of the glass ceramic wiring board 23. The removal condition of the restraining sheet 25 can be determined without worrying about the fluctuation, and therefore, the thickness fluctuation of one layer on the substrate surface due to the removal of the restraining sheet 23 can be suppressed.
[0046]
In the glass ceramic wiring board 23 obtained by the above method, the firing shrinkage occurs almost only in the thickness direction due to the action of the restraining sheet 25. Therefore, the shrinkage in the surface of the laminated body 21 is caused by, for example, the laminated body 21 having a rectangular shape. In this case, the shrinkage rate of the length of one side can be suppressed to 1% or less, and the glass ceramic wiring board 23 is uniformly and reliably bonded to the entire surface by the restraining sheet 25. It is possible to prevent warping or deformation due to partial peeling of 25 or the like.
[0047]
FIG. 3 shows a schematic cross-sectional view of an example of the glass ceramic wiring board 23 produced by the method for producing a multilayer wiring board obtained by the above method.
[0048]
The glass ceramic wiring substrate 23 shown in FIG. 3 is composed of an insulating substrate 33 formed by laminating a plurality of insulating layers 31a to 31d having a thickness of 50 to 250 μm, and between the insulating layers 31a to 31d and on the surface of the insulating substrate 33. A wiring circuit layer 35 made of high-purity metal foil having a thickness of about 9 to 18 μm is deposited.
[0049]
Furthermore, a via-hole conductor 37 having a diameter of 50 to 200 μm formed so as to penetrate the thickness direction of each of the insulating layers 31a to 31d is formed, whereby a circuit for connecting the wiring circuit layers 35 and achieving a predetermined circuit is formed. A net is formed. A semiconductor element or an electronic component is mounted on the surface of the wiring circuit layer 35.
[0050]
In the present invention, the glass ceramic wiring board 23 has a thermal expansion coefficient of 8 × for reducing the average thermal expansion coefficient difference with an external circuit board such as a printed circuit board to increase mounting reliability. 10^-6/ ° C or higher, especially 9 × 10^-6/ ° C. or higher is desirable.
[0051]
【Example】
A glass ceramic wiring board, which is one of the multilayer wiring boards, was produced as follows.
[0052]
First, SiO₂-BaO-B₂O_Three-Al₂O_ThreeAmorphous glass powder with an average particle size of 5 μm, quartz powder with an average particle size of 5 μm, chromium oxide (Cr₂O_Three) Glass ceramic composition A and SiO having a ratio of 50% by mass: 50% by mass: 0.3% by mass, respectively,₂-Al₂O_Three-MgO-B₂O_Three-ZnO-based crystalline glass powder with an average particle size of 3 μm, SiO with an average particle size of 1 μm₂Glass powder, ZnO powder having an average particle diameter of 1 μm, cobalt oxide (Co_ThreeO_Four) A glass-ceramic composition B having a powder ratio of 75% by mass: 15% by mass: 10% by mass: 0.4% by mass was prepared.
[0053]
With respect to 100% by mass of the above composition A and composition B, isobutyl methacrylate having an average mass molecular weight of 400,000 as an organic binder is 12% by mass, and DBP (dibutyl phthalate) as a plasticizer is in a ratio of 5% by mass. Toluene was mixed as a solvent, and glass ceramic green sheets A1 and B1 having a thickness of 300 μm were prepared by a doctor blade method using the prepared slurry. The glass ceramic green sheet was designed to shrink to a thickness of 180 μm by restraint firing.
[0054]
On the other hand, a Cu foil having a purity of 99.5% or more was adhered to the polymer film, and a wiring circuit layer was formed by etching to produce a transfer sheet. The wiring width was 50 μm and the wiring circuit layer pitch was 100 μm. And after apply | coating the adhesive agent containing the organic substance component used for the said green sheet formation to the wiring circuit layer formation surface of the said transfer sheet by screen printing, a transfer sheet is laminated | stacked on glass ceramic green sheet A1, B1, 50 Thermocompression bonding was performed at 5 ° C. at 5 ° C. Thereafter, the transfer sheet was peeled off to form a unit wiring circuit layer having a wiring circuit layer. Further, five of these arbitrary one unit green sheets were laminated to form laminates A10 and B10.
[0055]
Regarding the composition of the constraining green sheet, for laminate A10, forsterite powder having an average particle diameter of 2 μm and SiO having an average particle diameter of 5 μm are used.₂-BaO-B₂O_Three-Al₂O_ThreeSystem amorphous glass powder and chromium oxide powder having an average particle size of 0.5 μm are mixed in the ratio shown in Table 1, and the thickness is determined using the same organic binder, plasticizer, and solvent as used in the production of the glass ceramic green sheet A1. A 300 μm constraining green sheet A2 was produced.
[0056]
For the laminate B10, an alumina powder having an average particle diameter of 2 μm is mixed with SiO powder having an average particle diameter of 3 μm.₂-Al₂O_Three-MgO-B₂O_Three-ZnO-based crystalline glass powder and cobalt oxide powder having an average particle size of 0.9 μm are mixed in the ratio shown in Table 1, and thick using the same organic binder, plasticizer, and solvent as in the production of the glass ceramic green sheet B1. A constraining green sheet B2 having a thickness of 300 μm was produced.
[0057]
Next, the restraining green sheet A1 was pressure laminated at 50 ° C. and 5 MPa on both upper and lower surfaces of the laminate A10, and the laminate A20 composed of a plurality of green sheets was sandwiched between the restraining green sheets A2. Similarly, the laminate B20 made of the glass ceramic green sheet B1 was sandwiched by the constraining green sheet B2.
[0058]
Next, in order to disassemble and remove organic components such as organic binder by placing the laminates A20 and B20 sandwiched between the constraining green sheets A2 and B2 on a porous setter, a nitrogen atmosphere containing water vapor The mixture was heated to 750 ° C. and baked at 950 ° C. for 1 hour in the same atmosphere. After firing, the restraint sheet adhered to the upper and lower surfaces of the glass ceramic wiring board was observed for peeling. The firing shrinkage rate in the XY direction of the restraining sheet was evaluated by firing the restraining green sheet alone.
[0059]
Next, the restraining sheets bonded to the upper and lower surfaces of the glass ceramic wiring board were removed by blasting. The blasting conditions were such that the constraining sheet component was completely eliminated from the surface copper foil conductor. However, when the colorant is not contained in both the restraining sheet and the insulating layer made of glass ceramic, or the content of the colorant on the restraining sheet side is less than the content of the insulating layer made of glass ceramic. Since the color tone of the surface of the insulating layer made of glass ceramic was different from the original color tone under the blasting conditions, blasting was added until the original color tone of the insulating layer porcelain appeared. Then, the cross section of the produced glass ceramic wiring board was observed, and the thickness of the substrate surface layer was measured. Table 1 also shows the evaluation results of the shrinkage rate of the restraint sheet, the peeling of the restraint sheet after firing, and the substrate surface layer thickness after blasting.
[0060]
[Table 1]

[0061]
As is apparent from Table 1, sample No. 1 in which the same colorant was contained in the glass ceramic green sheet and the constraining green sheet. In 1-3, 5-10, the thickness of the surface layer of the glass ceramic wiring board was 180 ± 5 μm, and the surface layer thickness could be brought close to the design value.
[0062]
On the other hand, Sample No. No. in which a colorant was added to the glass ceramic green sheet but no colorant was added to the constraining green sheet. In Nos. 4 and 11, the colorant on the surface layer of the glass ceramic wiring board diffuses to the restraint sheet side, so that the color tone of the surface layer of the glass ceramic substrate becomes whitish and the ceramic powder on the restraint sheet is completely removed until the original color tone of the substrate itself appears. When a large amount of the substrate surface was shaved, the thickness of one layer on the substrate surface was significantly thinner than the designed value.
[0063]
【The invention's effect】
As described above in detail, according to the present invention, the same colorant is contained in the glass ceramic green sheet and the constraining green sheet, so that coloring is performed in the vicinity of the interface between the constraining sheet and the glass ceramic wiring board after firing. Because there is no color tone distribution due to the concentration distribution of the agent, the removal conditions of the restraint sheet are determined without worrying about fluctuations in the color tone of the substrate when removing the ceramic powder of the restraint sheet from the surface of the glass ceramic wiring board. For this reason, the thickness fluctuation of one layer on the substrate surface due to the removal of the restraining sheet can be suppressed, so that a multilayer wiring board with high dimensional accuracy can be obtained.
[Brief description of the drawings]
FIG. 1 is a process diagram for explaining a method of manufacturing a multilayer wiring board according to the present invention.
FIG. 2 is a process diagram for producing a transfer sheet used in the production of the multilayer wiring board of the present invention.
FIG. 3 is a schematic cross-sectional view of a multilayer wiring board obtained by the method for manufacturing a multilayer wiring board of the present invention.
[Explanation of symbols]
1 Glass ceramic green sheet
3 Green sheet for restraint
7 Wiring circuit layer
21 Laminate

Claims (3)

After forming a conductor wiring circuit layer on the surface of the glass ceramic green sheet containing glass powder, inorganic filler powder and organic binder, a plurality of the glass ceramic green sheets are laminated to form a laminate, and the upper and lower surfaces of the laminate A constraining green sheet that can maintain porosity at the firing temperature of the glass ceramic green sheet is laminated and laminated, and the laminate is suppressed from shrinking in the plane direction at a temperature lower than the melting point of the conductor wiring circuit layer. In the manufacturing method of the multilayer wiring board formed by firing,
To together when the constraining green sheet containing ceramic powder and glass powder, becomes the glass ceramic green sheets and the constraining green sheet containing the same colorant,
The glass ceramic green sheet contains chromium oxide (Cr ₂ O ₃ ) as a coloring agent in an amount of 0.1% with respect to a total of 100% by mass of the glass powder and the inorganic filler powder. 3 with containing mass%, per 100 wt% of the constraining green sheet is the ceramic powder and the glass powder, the chromium oxide as a coloring agent (Cr ₂ O ₃₎ 0.1~0.6 The glass ceramic green sheet contains 0.4% by mass of cobalt oxide (CoO) as the colorant with respect to a total of 100% by mass of the glass powder and the inorganic filler powder. The method for producing a multilayer wiring board, wherein the constraining green sheet contains 0.5% by mass of cobalt oxide (CoO) as the colorant with respect to a total of 100% by mass of the ceramic powder and the glass powder. . The method for producing a multilayer wiring board according to claim 1 , wherein a firing shrinkage rate of the constraining green sheet is 0.05 to 0.5%. Method for manufacturing a multilayer wiring board according to claim 1 or 2, wherein the conductive wiring circuit layers is a copper foil.

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