JP2011154807A - Copper-metalized composition and glass ceramic wiring board using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a copper-metalized composition and a glass ceramic wiring board using the same which reduce plating film defects in a metalized wiring layer formed on the surface of a glass ceramic insulating board and improves an adhesive strength between the metalized wiring layer and the glass ceramic insulating board. <P>SOLUTION: A mixture of copper powder and palladium-coated glass powder is provided as the copper-metalized composition. Using this copper-metalized composition, a metalized wiring layer made of the copper and the palladium-coated glass powder is formed on the surface a glass ceramic insulating board to form the glass ceramic wiring board. Through this process, solder film defects in the metalized wiring layer are reduced, and the adhesive strength between the metalized wiring layer and the glass ceramic insulating board is enhanced. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to, for example, a copper metallized composition that can be fired simultaneously with a glass ceramic insulating substrate, and a glass ceramic wiring substrate comprising the same as a conductor layer.

  Conventionally, as an insulating substrate for various wiring boards such as a package for housing a semiconductor element for accommodating a semiconductor element such as an IC or LSI, and a hybrid integrated circuit device in which various electronic components are mounted in addition to the semiconductor element, Alumina ceramics have been frequently used because of their excellent chemical stability and other characteristics.

  In recent years, wiring boards on which semiconductor elements such as ICs and LSIs with higher frequency and higher density are mounted are required to have a lower dielectric constant and lower wiring resistance than insulating boards made of alumina ceramics. As such an insulating substrate, glass ceramics are used, and as a low-resistance conductor that can be fired simultaneously with glass ceramics, for example, copper (Cu), gold (Au), silver (Ag) Attention has been paid to forming a wiring layer.

  Insulating substrates made of glass ceramics are being developed as glass-ceramic wiring substrates combined with low-resistance conductors for wiring substrates used in the communications field where high frequency and high density are advancing. Ceramic wiring boards with a conductor layer have been intensively developed.

  A ceramic wiring board using glass ceramics as an insulating substrate is generally obtained by molding a slurry prepared using a glass ceramic raw material powder, an organic binder, and a solvent by a sheet molding method such as a doctor blade method. A ceramic green sheet is punched with through-holes, and the through-hole is filled with a copper paste containing a copper metallized composition, and then a predetermined conductor pattern is printed on the green sheet using a similar copper paste. A thick film technique such as a method is used for printing and laminating a plurality of sheets under pressure, heating the laminate to remove the binder, and then firing the laminate.

  In this case, in a ceramic wiring board using glass ceramics as an insulating substrate, the shrinkage of the copper metallized composition that is co-fired is lower than the shrinkage start temperature at the time of firing the glass ceramics that is the insulating substrate. Since the starting temperature is 600 to 700 ° C. and the firing shrinkage curves are completely different, the ceramic wiring board obtained after the simultaneous firing is likely to be greatly warped.

  For this reason, various inorganic components are added to the copper metallized composition so as to bring the shrinkage curve of the copper metallized composition closer to the shrinkage curve of the glass ceramic, thereby reducing the warpage of the ceramic wiring board. .

For example, as a copper metallized composition that can be fired at a low temperature of 1000 ° C. or lower, copper (Cu) as a main component is added to CuO, Cu ₂ O, Al ₂ O ₃ , Bi ₂ O ₃ , MoO ₃ , Cr ₂ O _3. A copper metallized composition to which various inorganic components such as the above are added has been proposed (for example, Patent Documents 1 to 3).

Japanese Patent Laid-Open No. 4-83781 See JP-A-5-4884 JP-A-10-95686

  However, if the shrinkage curve of the copper metallized composition is made closer to the shrinkage curve of the glass ceramic, the amount of the inorganic component added to the copper metallized composition must be increased. As a result, the surface of the metallized wiring layer is inorganic. Since the components are exposed, when a plating film to be formed later is formed on the surface of the metallized wiring layer, a portion where the plating film is not formed (generally referred to as a chip) is formed, and the appearance yield is increased. There was a problem that decreased.

  On the other hand, when the amount of the inorganic component added in the copper metallized composition is reduced, the chipping of the plating film can be reduced, but there is a problem that the adhesive strength between the metallized wiring layer and the glass ceramic insulating layer is lowered. It was.

  Therefore, the present invention can reduce the chipping of the plating film in the metallized wiring layer formed on the surface of the glass ceramic insulating substrate, and can increase the adhesive strength between the metalized wiring layer and the glass ceramic insulating substrate. It is an object to provide a composition and a ceramic wiring board using the composition.

  The copper metallized composition of the present invention is characterized by comprising a mixture of copper powder and glass powder coated with palladium.

  The copper metallized composition preferably contains 95 to 98% by mass of the copper and 2 to 5% by mass of the glass powder coated with the palladium.

  Moreover, in the said copper metallization composition, it is desirable that the softening point of glass powder is 890-950 degreeC.

  Furthermore, in the copper metallized composition, it is desirable that the amount of palladium in the glass powder coated with palladium is 10 to 300 ppm by mass.

  The glass ceramic wiring board of the present invention is a glass ceramic wiring board comprising a glass ceramic insulating substrate and a metallized wiring layer formed on the surface of the glass ceramic insulating substrate, wherein the metallized wiring layer comprises copper and palladium. Are formed from coated glass particles.

  In the glass-ceramic wiring board, the metallized wiring layer preferably contains 95 to 98% by mass of the copper and 2 to 5% by mass of glass particles coated with the palladium.

  According to the copper metallized composition of the present invention, it can be used as a composition of a metallized wiring layer formed on the surface of a glass ceramic insulating substrate, thereby reducing chipping of a plating film formed thereon and a metallized wiring layer. And the glass ceramic insulating substrate can be increased in adhesive strength.

In addition, according to the glass ceramic wiring board of the present invention, chipping of the plating film in the metallized wiring layer is suppressed, and the adhesive strength between the metallized wiring layer and the glass ceramic insulating substrate is increased. It can be.

It is a schematic sectional drawing of one Embodiment of the glass-ceramic wiring board of this invention. It is an expanded sectional view of the metallized wiring layer of the surface layer which is the principal part of the glass ceramic wiring board of the present invention.

  The copper metallized composition of the present invention comprises a mixture of copper powder and glass powder coated with palladium.

  When a conductor pattern is formed using a copper metallized composition containing glass powder coated with palladium, the coated palladium is an active metal, so the conductor pattern using the copper metallized composition is sintered. When plating the surface of the metallized wiring layer to be formed, a plating film having excellent adhesion can be formed on the glass powder.

  The copper powder desirably has a purity of 99% by mass or more. When the purity of the copper powder is 99% by mass or more, precipitation and floating of impurities can be reduced on the surface of the copper metallized wiring layer, and thus appearance defects such as chipping of the plating film on the surface of the metallized wiring layer can be prevented.

  The average particle size of the copper powder is desirably 2 to 5 μm. When the average particle diameter of the copper powder is 2 to 5 μm, the shrinkage curve of the conductor pattern containing the copper powder becomes close to the shrinkage curve of the glass ceramic, and the metallized wiring layer and the glass ceramic insulating substrate formed after the co-firing It becomes possible to suppress the curvature of the glass-ceramic wiring board formed from this.

The glass powder constituting the copper metallized composition must be appropriately selected according to the composition of the glass component forming the glass ceramic insulating substrate, but the copper metallized composition is the glass component forming the glass ceramic insulating substrate. As a metal oxide, SiO ₂ , Al ₂ O ₃ , CaO, and the like are used in terms of preventing early sintering due to infiltration and strengthening the adhesive strength at the interface between the glass ceramic insulating substrate and the metallized wiring layer. It is desirable to use a glass having a high melting point containing SrO and BaO as components. As specific glass composition, for example, SiO ₂ is 40 to 60% by mass, Al ₂ O ₃ is 5 to 20% by mass, CaO is 10 to 20% by mass, SrO is 1 to 5% by mass, and BaO is 15%. What is -25 mass% can be used. Moreover, it is desirable to use a glass having a softening point of 890 ° C. to 950 ° C. as the glass having the above composition. When glass is composed of SiO ₂ , Al ₂ O ₃ , CaO, SrO and BaO and has a high softening point, the glass powder shape must be maintained in the metallized wiring layer even after firing. In addition, since the glass powder exists while maintaining its shape, palladium can be present on the surface of the glass powder even in the metallized wiring layer. As a result, it becomes possible to make active palladium exist on the surface of the glass powder that is raised on the surface of the metallized wiring layer. Further, it is possible to prevent appearance defects such as chipping of the plating film on the surface of the copper metallized wiring layer. In addition, the softening point of the glass powder coated with palladium in the present invention is determined by measurement using differential thermal analysis (DTA). In this case, it is an exothermic peak seen between the glass transition point and the crystallization temperature.

The glass powder coated with palladium is in a state where palladium is coated on the surface of the glass powder, and most of the palladium is present near the surface of the glass powder. In this case, the amount of palladium in the glass powder coated with palladium is desirably 5 to 300 ppm by mass ratio. When the amount of palladium is 5 to 300 ppm by mass, almost the entire surface of the glass powder can be covered with palladium. Therefore, when plating is performed on the surface of the glass powder coated with palladium, the surface of the glass powder can be activated, and it becomes easy to form a plating film on the surface of the glass powder.

The glass powder is coated with palladium by immersing the glass powder in an aqueous solution of palladium chloride. The amount of palladium to be coated is adjusted depending on the immersion time. In order to strengthen the adhesion of palladium attached to the surface of the glass powder, the surface of the glass powder to be used should have fine irregularities. In this case, minute irregularities are formed by etching the surface of the glass powder. Various etching solutions can be used as the etching solution as long as the solution can selectively dissolve any of the components constituting the glass powder. The more preferable etching solution is a main component of the glass powder. It is desirable to use an aqueous ammonium fluoride solution in that SiO ₂ can be selectively dissolved.

  The shape of the glass powder may be either spherical or indeterminate, but it is spherical in that palladium can be more uniformly dispersed on the surface of the glass powder, and it has excellent dispersibility when mixed with copper powder. Or a thing close to a sphere is good.

  The copper metallized composition preferably contains 95 to 98% by mass of copper and 2 to 5% by mass of glass powder coated with palladium. When the copper of the copper metallized composition is 95 to 98% by mass and the glass powder coated with palladium is 2 to 5% by mass, the proportion of copper is large, and active metal is also present on the surface of the glass powder. Therefore, it becomes easy to form a plating film. In addition, because the glass powder contained in the copper metallized composition has both palladium (metal component) and glass powder (ceramic component), at the interface between the copper metallized wiring layer and the glass ceramic insulating substrate, The glass powder coated with palladium is firmly bonded to both the copper constituting the metallized wiring layer and the glass ceramics constituting the glass ceramic insulating substrate. Thus, it is possible to increase the adhesive strength of the metallized wiring layer on the glass ceramic insulating substrate.

  Further, when the copper metallized composition contains 95 to 98% by mass of copper and 2 to 5% by mass of glass powder coated with palladium, the sintering behavior of the conductor pattern using the copper metallized composition As a result, it becomes possible to obtain a glass-ceramic wiring board with very little warpage or undulation.

  The copper metallized composition of the present invention is composed of a mixture of copper powder and glass powder coated with palladium as an inorganic component, and this copper powder is mixed with glass powder coated with palladium. It can be used as a copper metallized paste containing an organic vehicle.

  The copper metallized composition of the present invention can be applied to a glass ceramic wiring board provided with a copper metallized wiring layer.

  First, a slurry is prepared using a predetermined glass ceramic powder to form a glass ceramic green sheet, and then a copper metallized paste using the copper metallized composition of the present invention is printed on the main surface of the glass ceramic green sheet. To form a desired conductor pattern. In addition, a via hole is formed in the glass ceramic green sheet, and before the conductor pattern is formed by printing the copper metallized paste on the main surface of the glass ceramic green sheet, or at the same time as forming the conductor pattern, the conductor paste is formed in the via hole. It is also possible to form via-hole conductors by filling them.

  Next, a plurality of glass ceramic green sheets on which conductor patterns are formed are laminated to form a laminated body, which is fired under a predetermined temperature condition to form an element body of the glass ceramic wiring board. Thereafter, a plating layer of Cu, Au, Ni, Sn, solder, or the like is formed on the surface of the metallized wiring layer of the body of the glass ceramic wiring substrate by an electrolytic plating method or an electroless plating method. Can be completed.

  When firing, in order to decompose and disperse the organic binder from the glass ceramic green sheet and the copper metallized paste, the binder is heated up to the binder removal temperature, the binder is removed, and then the temperature is raised to a predetermined temperature. In addition, since the copper metallized paste is used, it is preferable to degrease the glass ceramic green sheet in a non-oxidizing atmosphere such as a nitrogen atmosphere. Moreover, it is desirable that the maximum temperature for firing is lower than the softening point of the glass powder contained in the copper metallized composition. When the maximum temperature of firing is a temperature lower than the softening point of the glass powder contained in the copper metallized composition, the glass powder in the metallized wiring layer exists in a state of retaining the shape even after firing. This is because palladium can be maintained on the surface. As a result, the metallized wiring layer obtained even after firing can be held in a shape with small thinning and deformation, and thereby the dimensional accuracy of the metallized wiring layer can be increased.

  In addition, a conductor pattern is formed using a copper metallized composition containing a glass powder having a softening point of 890 ° C. to 950 ° C., and is fired at a temperature lower than the softening point of the glass powder, whereby a metallized wiring having a rectangular cross section Since the layers can be easily formed, it is possible to easily form a high-density metallized wiring layer with a narrow width and interval between the wiring layers.

  When glass powder coated with palladium is used for the copper metallized composition that constitutes the copper metallized paste as described above, the glass powder is formed on the surface and inside of the metallized wiring layer even if co-fired with the glass ceramic green sheet. Exists in a state of being coated with palladium, so even when plating is performed on the surface of the metallized wiring layer, the surface of the glass powder is activated with palladium, and also on the surface of the glass powder. A plating film is sufficiently formed. Therefore, appearance defects such as chipping of the plating film on the surface of the copper metallized wiring layer can be prevented.

As a low-temperature fired glass ceramic material for forming a glass ceramic green sheet, SiO ₂ —B ₂ O ₃ —RO system (R is an alkaline earth metal), SiO ₂ —BaO—Al
_At least one glass selected from the group of ₂ O ₃ —RO, SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —RO, and SiO ₂ —Al ₂ O ₃ —RO is preferable. As the ceramic filler, a composition in which Al ₂ O ₃ or SiO ₂ (quartz, cristobalite) is added and ZnO, PbO, Pb, ZrO ₂ , TiO ₂ or the like is further blended can be used. In this case, it is desirable that the ceramic filler is mixed at a rate of 20 to 80% by mass and the glass is mixed at a rate of 20 to 80% by mass in order to achieve both the characteristics of the material and the sinterability at low temperature firing. Preferred compositions of the _glass, SiO 2: 35 to 45 wt%, MgO: 15-25 wt%, BaO: 15-25 _{wt%, Al} 2 O 3: _{6~10 wt%, B 2} O 3: _5~ 10 wt%, CaO: 2 to 3 wt%, SrO: 0.5 to 2 _wt%, ZrO 2: is preferable made of 0.5-2 wt%.

  Hereinafter, the glass ceramic wiring board obtained using the copper metallized composition of the present invention will be described with reference to the drawings. In addition, here, what constitutes the copper metallized composition is glass powder, and when the metallized wiring layer in the glass ceramic wiring substrate is constituted, it is glass particles.

  FIG. 1 is a cross-sectional view of a glass ceramic wiring board according to an embodiment of the present invention, which is a multilayer wiring board composed of a plurality of glass ceramic insulating layers. FIG. 2 is an enlarged cross-sectional view of the metallized wiring layer in the surface layer region of the glass ceramic wiring board.

  As shown in FIG. 1, the glass ceramic wiring board has a glass ceramic insulating board 2 formed by laminating a plurality of glass ceramic insulating layers 1, and a metallized wiring layer 3 formed on the surface and inside thereof. ing. Further, in the glass ceramic insulating substrate 2, via hole conductors 5 penetrating the glass ceramic insulating layers 1 in the thickness direction are formed, and the metallized wiring layers 3 formed on the surface and inside are electrically connected to each other. It is supposed to be.

  Here, among the metallized wiring layers 3 formed on the glass ceramic wiring substrate, the metallized wiring layer 3 provided for mounting the semiconductor element on the upper surface side of the glass ceramic insulating substrate 2 is a surface layer wiring layer 3a. Further, the metallized wiring layer 3 provided on the lower surface side of the glass ceramic wiring board forms the connection pad 3b.

  The glass ceramic wiring board of the present invention has a metallized wiring layer 3 (here, the surface wiring layer 3a and the connection pad 3b) provided on the upper surface side and the lower surface side of the glass ceramic insulating substrate 2, copper 3ba, and palladium 3bb. It is comprised from the covered glass particle 3bc. Thus, when plating is performed on the surface of the metallized wiring layer 3 provided on the upper surface side and the lower surface side of the glass ceramic insulating substrate 2, a plating film is easily formed on the surface of the glass particles 3bc covered with palladium 3bb. It is possible to reduce appearance defects such as chipping of the plating film, and to increase the adhesive strength between the metallized wiring layer 3 and the glass ceramic insulating substrate 2.

  Moreover, as for the glass ceramic wiring board of this invention, it is desirable that the metallized wiring layer 3 of a surface layer contains 2-5 mass% of glass particles 3bc by which 95-98 mass% of copper 3ba and palladium 3bb are coat | covered. When the surface metallized wiring layer 3 contains 95 to 98% by mass of copper 3ba and 2 to 5% by mass of glass particles 3bc coated with palladium, the proportion of copper 3ba is large, and the glass particles 3bc Since active palladium is also present on the surface, it is easy to form a plating film. Moreover, since the glass powder contained in the copper metallized wiring layer 3 has both palladium (metal component) and glass particles (ceramics component), the metallized wiring layer 3 of copper 3ba and the glass ceramic insulating layer 1 In order to firmly bond the glass particles 3bc coated with palladium 3bb to both the copper 3ba constituting the metallized wiring layer 3 and the glass ceramics constituting the glass ceramic insulating layer 1, It becomes possible to increase the adhesive strength of the metallized wiring layer 3 on the ceramic insulating layer 1.

  Further, when the copper metallized wiring layer 3 contains 95 to 98% by mass of copper and 2 to 5% by mass of the glass powder coated with palladium, the conductor pattern using the copper metallized wiring layer 3 is baked. Since the binding behavior can be made close to the sintering behavior of glass ceramics, as a result, it is possible to obtain a glass-ceramic wiring board with extremely little warpage or undulation.

In order to determine the content of glass particles 3bc coated with copper 3ba and palladium 3bb from the copper metallized wiring layer 3 formed on the obtained glass ceramic wiring substrate, the cross section of the metallized wiring layer 3 in the glass ceramic wiring substrate is obtained. Polishing to produce a polished surface, this cross section is subjected to an electron microscope apparatus (WDS (wavelength dispersive X-ray spectroscopic analysis), SEM-EDS (scanning electron microscope-energy dispersive X-ray spectroscopic analysis) equipped with an analyzer, Composition analysis is performed using TEM-EDS (transmission electron microscope-energy dispersive X-ray spectroscopic analysis). At this time, the presence of palladium 3bb and glass particles 3bc in the metallized wiring layer 3 can also be confirmed by this method.

When the glass ceramic wiring board is mounted on an external circuit board such as a mother board, first, the glass ceramic wiring board is removed from the external circuit board, and an ion cross-section polishing apparatus (CP: cross section polisher) or the like is used. Then, the solder used for mounting is removed, and then quantitative analysis is performed by ICP. Here, the glass ceramic wiring board to be analyzed is pre-processed before the ICP analysis. As a pretreatment method, the glass ceramic insulating layer 1 exposed on the surface of the glass ceramic wiring substrate is masked with a resin or the like, and then only the metallized portion is dissolved or the glass ceramic insulating layer 1 is masked with a resin or the like. The composition can be determined by irradiating the part with laser using laser ablation and introducing evaporated fine particles into the ICP. Incidentally, in the case of obtaining the ratio of the glass particles 3bc palladium 3bb contained in metallized wiring layer is coated, the copper 3bb (density: 8.9g / ^cm 3), glass particles 3bc (Density: 3 g / cm ³ ) To obtain the density from the area ratio.

  Hereinafter, the copper metallized composition of the present invention and the glass ceramic wiring board using the same are evaluated based on one example.

First, the glass-ceramic green _sheets, SiO 2: 35 to 45 wt%, MgO: 15-25 wt%, BaO: 15-25 _{wt%, Al} 2 O 3: _{6~10 wt%,} B _{2 O} 3: 5 10% by mass, CaO: 2-3% by mass, SrO: 0.5-2% by mass, ZrO ₂ : 0.5-2% by mass, and quartz (SiO ₂ ) as a ceramic filler. As a raw material powder, a mixed powder was prepared by mixing 60% by mass of glass powder and 40% by mass of quartz. Next, 12% by mass of an organic binder (isobutyl methacrylate (i-BMA)), 5% by mass of a plasticizer (dibutyl phthalate (DBP)), and 50% by mass of toluene as a solvent with respect to 100% by mass of the mixed powder. Add 0.1% by mass of alkoxysilane as a silane compound and mix for 20 hours with a ball mill to prepare a slurry. The slurry is formed to a thickness of 0.1 mm by the doctor blade method to produce a glass ceramic green sheet. did.

Next, the copper metallized paste is first composed of SiO ₂ , Al ₂ O ₃ , CaO, SrO and BaO, 40 to 60% by mass of SiO ₂ , 5 to 20% by mass of Al ₂ O _{3 and} 10 to 20% of CaO. Glass powders having different softening points were prepared by changing the composition ratio within a range of 1% by mass, 1-5% by mass of SrO, and 15-25% by mass of BaO. At this time, the average particle diameter of the glass powder was 2 μm.

  Next, this glass powder was immersed in an aqueous ammonium fluoride solution and etched to form irregularities on the surface of the glass powder. Next, the glass powder with irregularities formed on the surface was immersed in an aqueous palladium chloride solution, and palladium was adhered to the surface of the glass powder to produce a glass powder coated with palladium. In this case, the amount of palladium relative to the glass powder coated with palladium was changed by changing the immersion time in the palladium chloride aqueous solution. The amount of palladium contained in the glass powder coated with palladium was confirmed by ICP. As a result of analysis, the amount of palladium contained in the produced glass powder coated with palladium was the value shown in Table 1.

Next, a copper powder having an average particle size of 3 μm is prepared, and glass powder coated with palladium is added so as to have the ratio shown in Table 1 with respect to 100% by mass of the copper powder. A copper metallized paste was prepared by adding dibutyl phthalate as a plasticizer and terpineol as a solvent.

  Separately, the same amount of glass powder not coated with palladium was added to prepare a conductor paste for a via-hole conductor.

  Next, a via hole was formed in the glass ceramic green sheet using a laser, and a via hole conductor paste was filled in the via hole by a printing method to form a via hole conductor. Next, a copper metallized paste for the surface layer was printed on the upper surface of the via-hole conductor to form a conductor pattern. The size of the conductor pattern was adjusted so that the diameter after firing was 0.86 mm and the thickness was about 15 μm.

  Next, after laminating 20 layers of glass ceramic green sheets without via-hole conductors and conductor patterns on the glass-ceramic green sheets with via-hole conductors and conductor patterns, heating in a nitrogen atmosphere and degreasing, And firing at 880 ° C. to obtain an element body of a glass ceramic wiring board.

  Next, the activated body of the produced glass ceramic wiring board was subjected to palladium activation treatment for about 30 seconds, and then the surface of the metallized wiring layer on the surface of the glass ceramic wiring board was subjected to nickel plating with a thickness of 1 μm. A glass ceramic wiring board having a metallized wiring layer in which a nickel plating film and a gold plating film are formed on the surface of the metallized wiring layer was prepared by performing gold plating with a thickness of 0.1 μm.

  Next, a flux is applied to the surface of the metallized wiring layer on which the nickel plating film and the gold plating film are formed, and a Sn / Pb eutectic solder ball having a diameter of 0.86 mm is further placed on the surface at 245 ° C. for 1 minute. It was held and solder balls were attached.

  Next, the following evaluation was performed on the produced ceramic wiring board to which the solder balls were attached.

  The adhesive strength of the metallized wiring layer was determined by pulling the solder ball in the vertical direction and measuring the tensile strength using a clamp pull strength measuring machine. The measurement evaluated 30 samples per condition, and Table 1 shows the minimum value among the samples. And the case where the minimum value of tensile strength exceeded 19.6 MPa was made into the quality product.

  Plating properties were evaluated using a scanning electron microscope (SEM) based on the presence or absence of plating defects and the spread of plating on the surface of the glass ceramic insulating substrate. The defect of the plating was judged as “defect” when the surface of the plating film formed on the surface of the observed metallized wiring layer had a pinhole larger than 5 μm as “defect”.

  In the remarks column of Table 1, when the spread of the plating film is larger than 20 μm, it is indicated as “plating spread”, and when a pinhole having a diameter of 5 μm or less is observed, it is indicated as “pinhole”.

The ratio of the glass particles coated with palladium contained in the metallized wiring layer formed on the produced glass ceramic wiring board is a polished surface by polishing the cross section of the metalized wiring layer of the produced glass ceramic wiring board, This cross section is obtained by analyzing an electron microscope apparatus (WDS (wavelength dispersive X-ray spectroscopic analysis), SEM-EDS (scanning electron microscope-energy dispersive X-ray spectroscopic analysis), TEM-EDS (transmission electron microscope-energy) equipped with an analyzer. Composition analysis was performed using dispersive X-ray spectroscopy)). At this time, the presence state of palladium or glass powder in the metallized wiring layer 3 was also confirmed by this method. In addition, when calculating | requiring the ratio of the glass powder coat | covered with the palladium contained in a metallized wiring layer, copper (density: 8.9 g / cm < ³ >)
) And the density of the glass particles (density: 3 g / cm ³ ).

  When the glass ceramic wiring board is mounted on an external circuit board such as a mother board, first, the glass ceramic wiring board is removed from the external circuit board, and an ion cross-section polishing apparatus (CP: cross section polisher) or the like is used. The solder used for mounting was removed, and then quantitative analysis was performed by ICP. Here, a glass-ceramic wiring board to be analyzed was pretreated before ICP analysis. The pretreatment method consists of irradiating a portion of the glass ceramic insulating layer exposed on the surface of the glass ceramic wiring substrate with a resin or the like by irradiating the laser with laser ablation and introducing evaporated fine particles into the ICP. Asked. In the produced glass ceramic wiring substrate, it was confirmed that the ratio of the glass powder coated with palladium contained in the metallized wiring layer was the value shown in Table 1.

  As is clear from the results in Table 1, in the sample of the glass ceramic wiring board having the metallized wiring layer produced using the copper metallized composition of the present invention (sample Nos. 6 to 23), the plating property is good. And the adhesive strength of the metallized wiring layer was 19.6 MPa or more.

Moreover, the sample (sample No. 7-16) of the glass ceramic wiring board which has a metallized wiring layer whose copper is 95-98 mass% and the glass powder by which palladium is coated is 2-5 mass%
18-23), the plating property was good and the adhesive strength of the metallized wiring layer was 29.4 MPa or more, and peeling occurred at the interface between the glass ceramic insulating layer and the metallized wiring layer.

  Further, in the metallized wiring layer in which the copper is 95 to 98% by mass and the glass particles coated with palladium is 2 to 5% by mass, the softening point of the glass powder coated with palladium is 890 to 950 ° C. In the glass ceramic wiring board samples (sample Nos. 7 to 16, 18, 20, and 21) having the wiring layer, the plating property was good and the adhesive strength of the metallized wiring layer was 39.2 MPa or more.

  Furthermore, the glass powder coated with 95 to 98% by weight of copper and the glass powder coated with palladium is 2 to 5% by weight, and the softening point of the glass powder coated with palladium is 890 to 950 ° C., Further, samples of glass ceramic wiring boards having a metallized wiring layer in which the amount of palladium contained in the glass powder is 10 to 300 ppm by mass (Sample Nos. 7, 9, 10 to 12, 15, 16, 18, 20 and In 21), the surface of the metallized wiring layer had no pinhole with a diameter of 5 μm or less, the plating property was extremely good, and the adhesive strength of the metallized wiring layer was 39.2 MPa or more.

  On the other hand, in the sample (sample No. 1-5) of the glass ceramic wiring board which has the metallized wiring layer produced using the copper metallized composition using the glass powder which has not coat | covered palladium, of metallized wiring layer Chipping of the plating film was observed on the surface.

DESCRIPTION OF SYMBOLS 1 ... Glass ceramic insulating layer 2 ... Glass ceramic insulating substrate 3 ... Metallized wiring layer 3a ... Surface wiring layer 3b ... Connection pad 3ba ... Copper 3bb ... Palladium 3bc ... Glass particles 5 ... via hole conductor

Claims (6)

  A copper metallized composition comprising a mixture of copper powder and glass powder coated with palladium.   2. The copper metallized composition according to claim 1, comprising 95 to 98% by mass of the copper and 2 to 5% by mass of the glass powder coated with the palladium.   The copper metallized composition according to claim 2, wherein the softening point of the glass powder is 890 to 950 ° C.   4. The copper metallized composition according to claim 3, wherein the amount of palladium in the glass powder coated with palladium is 10 to 300 ppm by mass.   A glass ceramic wiring substrate comprising a glass ceramic insulating substrate and a metallized wiring layer formed on the surface of the glass ceramic insulating substrate, wherein the metallized wiring layer comprises glass particles coated with copper and palladium. A glass ceramic wiring board characterized by being formed.   6. The glass ceramic wiring board according to claim 5, wherein the metallized wiring layer contains 95 to 98 mass% of the copper and 2 to 5 mass% of glass particles coated with the palladium.

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