JP2010027363A - Ceramic component, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ceramic component which has a ceramic substrate with an excellent mechanical strength and few deformation and a conductor of low resistance and suitable shape, with an excellent adhesion strength and simultaneous sintering with the ceramic substrate. <P>SOLUTION: The ceramic wiring substrate 10 has conductors 18, 19, 23, 27, 28 formed on a ceramic substrate 11 made of mainly ceramic which is sintered at a temperature higher than the melting point of copper. The conductors 18, 19, 23, 27, 28 are composed of a mixed phase of an inorganic compound filler and copper. The filler is mainly made of at least two kinds of inorganic compounds selected from an titanium-aluminum based metal compound, a titanium oxide and an aluminum oxide. It is preferable that the titanium oxide and the aluminum oxide in the filler are produced by thermal decomposition and oxidization of the titanium-aluminum based metal compound. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ceramic component and a method for manufacturing the same, and more particularly to a ceramic component characterized by the composition of a conductor and a method for manufacturing the same.

  In recent years, semiconductor integrated circuit elements (IC chips) used as computer microprocessor units (MPUs) have become increasingly faster and more functional, with an accompanying increase in the number of terminals and the pitch between terminals. Tend to be narrower. In general, a large number of terminals are densely arranged on the bottom surface of an IC chip, and such a terminal group is connected to a terminal group on the motherboard side in the form of a flip chip. However, it is difficult to connect the IC chip directly on the mother board because there is a large difference in the pitch between the terminals on the IC chip side terminal group and the mother board side terminal group. For this reason, a method is generally employed in which a package is prepared by mounting an IC chip on an IC chip mounting wiring board, and the package is mounted on a motherboard.

  Various insulating materials can be used for the IC chip mounting wiring board constituting this type of package, and examples of which use ceramics are well known. This type of package, called a ceramic package, is mainly made of a ceramic material mainly composed of alumina for the insulator part and tungsten, which is a refractory metal that can be fired simultaneously with alumina, for the conductor part. Yes. The ceramic package made of the above material has advantages such as excellent mechanical properties due to its high strength and high sealing performance, but has a disadvantage that the wiring resistance of the conductor portion is higher than that of the copper wiring. ing.

  Here, as a combination of materials that may obtain a ceramic part having excellent mechanical characteristics despite the low wiring resistance of the conductor portion, for example, a ceramic material mainly composed of alumina in an insulator portion is used. It has been proposed to use a mixture of tungsten and copper for the conductor portion (see, for example, Patent Document 1).

  However, when manufacturing a ceramic package having a conductor made of copper-tungsten as in the prior art, assuming that the firing temperature is set to a low temperature according to low melting point copper (1083 ° C.), simultaneous firing is performed. The sintering of alumina becomes insufficient and the desired strength cannot be achieved.

Thus, in the case of a ceramic component using a low-resistance metal material for the conductor portion, it is difficult to perform firing at a temperature higher than the melting point of copper. Therefore, in recent years, ceramic parts using a low-temperature fired material such as glass ceramic for the insulator portion and a mixture of copper and an inorganic component (metal oxide such as alumina or zirconia) for the conductor portion have been proposed (for example, , See Patent Document 2). And, according to such a combination of materials, it is possible to effectively prevent deformation of the insulator part such as warpage and undulation, improve the adhesive strength at the interface between the conductor part and the insulator part, and achieve stable adhesive strength. It is believed that you can get.
JP 05-144316 A JP-A-10-95686

  However, in the case of the ceramic parts of the above prior art, since the firing shrinkage curves of the insulator part and the conductor part are completely different, if the proportion of the inorganic component in the conductor part is small, the deformation of the insulator part or the conductor part There arises a problem such as peeling between the insulating portion and the insulating portion. Therefore, in order to avoid such a problem, it is necessary to add a large amount of an inorganic component to the conductor portion. However, metal oxides such as alumina and zirconia basically have poor wettability with copper. Therefore, when a large amount of a metal oxide is added to the material and fired, the metal oxide is segregated in the conductor portion, resulting in an increase in the resistance of the conductor portion. Therefore, the superiority of containing low resistance copper in the conductor portion is impaired.

  Further, when the firing temperature is set in accordance with the ceramic portion whose sintering temperature is higher than the melting point of copper and co-firing is performed, copper having a low melting point melts, and the flow and volatilization of copper occurs with the melting. As a result, there arise problems that the shape of the conductor portion cannot be maintained, or that copper aggregates on the surface of the conductor portion.

  The present invention has been made in view of the above problems, and has an object of having a ceramic substrate that has excellent mechanical strength and little deformation, and has low adhesion strength and co-sinterability with the ceramic substrate. It is an object of the present invention to provide a ceramic component having a resistance and a conductor having a suitable shape, and a method for manufacturing the same.

  In order to solve the above-mentioned problems, the inventors of the present invention have conducted intensive research and sought a means for preventing the flow and volatilization of the molten copper by simultaneous firing. In order to keep it at a low level, a new finding was obtained that a filler mainly composed of a specific inorganic compound may be contained. It has also been newly found out that the adhesive strength and co-sinterability of the conductor can be improved by including a filler mainly composed of such a specific inorganic compound. The inventors of the present application have further developed these new findings and have come up with the following solution.

  That is, as means (means 1) for solving the above-mentioned problem, in a ceramic component in which a conductor is formed on a ceramic base mainly composed of ceramic sintered at a temperature higher than the melting point of copper, the conductor is made of titanium. There is a ceramic part characterized by comprising a mixed phase of copper and a filler mainly composed of at least two kinds of inorganic compounds selected from aluminum-based metal compounds, titanium oxides and aluminum oxides.

  Therefore, according to the means 1, since the conductor is formed including copper, the resistance is lower than that of a conductor formed using tungsten as a main component. In addition, since it is a conductor composed of a mixed phase of copper and a filler mainly composed of at least two inorganic compounds selected from titanium-aluminum metal compounds, titanium oxides and aluminum oxides, it is melted at the time of simultaneous firing. Copper flow and volatilization is prevented. As a result, copper in the conductor is held in that position, and voids in the conductor and protrusion of the conductor from the ceramic portion are prevented. As a result, a conductor having a relatively favorable shape can be obtained.

  Moreover, since a filler mainly composed of at least two kinds of inorganic compounds selected from titanium-aluminum-based metal compounds, titanium oxides and aluminum oxides is used, simultaneous sinterability is improved. Since the firing shrinkage ratios of these are also matched, simultaneous firing can be performed without causing warpage or peeling.

  From the above, according to the above means 1, a low resistance and suitable shape conductor having an excellent mechanical strength and having a ceramic substrate with little deformation, and having excellent adhesion strength and simultaneous sintering with the ceramic substrate. It is possible to provide a ceramic component having the same.

  Here, the ceramic component is not particularly limited as long as a conductor is formed on a ceramic base, and examples thereof include a ceramic wiring board, a ceramic capacitor, a ceramic inductor, and a ceramic sensor.

  As said ceramic wiring board, what is equipped with the inner layer conductor pattern and via conductor formed in the inside of the said ceramic base | substrate, and the mounting pad formed on the surface of the said ceramic base | substrate can be mentioned, for example. In addition, the ceramic capacitor has a plate shape having a main surface and a back surface, and a ceramic substrate in which a plurality of inner layer electrodes are stacked and disposed via a dielectric mainly composed of barium titanate; A plurality of via conductors formed in a plurality of via holes extending along the thickness direction and connected to the plurality of inner layer electrodes, and to be connected to at least the main surface side end portions of the plurality of via conductors And a plurality of external electrodes arranged in the via array type multilayer ceramic capacitor in which the plurality of via conductors are arranged in an array as a whole.

  The ceramic substrate constituting the ceramic component is mainly composed of a ceramic that is sintered at a temperature higher than the melting point of copper (1083 ° C.).

  The ceramic as the insulator material is not particularly limited, and specific examples thereof include sintered bodies of high-temperature fired ceramics such as alumina, aluminum nitride, boron nitride, silicon carbide, and silicon nitride. A sintered body of low-temperature fired ceramic such as glass ceramic obtained by adding an inorganic ceramic filler such as alumina to borosilicate glass or lead borosilicate glass is not used here because it is weak in strength. Usually, the ceramic substrate is plate-shaped and has, for example, a rectangular shape in plan view.

  The conductor which comprises a ceramic component consists of a mixed phase of a filler mainly composed of at least two kinds of inorganic compounds selected from titanium-aluminum metal compounds, titanium oxides and aluminum oxides, and copper.

The reason for choosing copper as one of the conductor forming materials is that copper is a metal with a low electrical resistivity (1.69 × 10 ⁻⁸ Ω · m) compared to silver or gold. Because it is cheap.

  The conductor contains a filler mainly composed of the above inorganic compound in addition to copper. Here, the conductor needs to be a mixed phase, not an alloy phase of copper and the inorganic compound. The reason is that, in the case of the alloy phase, copper and the above-mentioned inorganic compound are united with each other, so that the flow and volatilization of the molten metal cannot be effectively prevented.

The inorganic compound needs to be at least two selected from a titanium-aluminum metal compound, a titanium oxide, and an aluminum oxide. The titanium-aluminum-based metal compound (titanium aluminide) is, for example, TiAl, TiAl ₃ , Ti ₃ Al, etc. Among them, TiAl is most preferable. The titanium oxide, for example, refers to _TiO, that such TiO 2, _Ti 2 _{O 5.} The aluminum oxide, for example, refers to such as _Al 2 _{O 3.} In this case, the inorganic compound is preferably composed mainly of two types of titanium oxide and aluminum oxide.

  Titanium oxide and aluminum oxide may be pre-contained in the conductor forming material, but are generated after the titanium-aluminum metal compound is thermally decomposed and oxidized after firing. It is preferable that The reason is as follows. That is, at the time of firing, a part or all of the titanium-aluminum metal compound is thermally decomposed and melted in copper, and then reacts with oxygen present in the surroundings to reprecipitate as oxide fine particles in copper. To do. This is because such oxide fine particles can be uniformly dispersed and segregation of copper is prevented, which contributes to the reduction in resistance of the conductor. In addition, since the titanium-aluminum metal compound reacts with oxygen in copper to reduce its concentration, this also contributes to lowering the resistance of the conductor.

  Among the fillers mainly composed of inorganic compounds as described above, fillers mainly composed of titanium-aluminum-based metal compounds are easy to get used to copper and easily wet, so even if they are mixed in a re-deposited state. It can disperse uniformly in copper without repelling copper. As a result, a thickening effect on the liquid copper melted at the time of simultaneous firing is exhibited, and the flow and volatilization of the molten copper are surely prevented. Incidentally, it is generally difficult to uniformly disperse the inorganic oxide in the metal, and even if it can be dispersed, the wettability with copper is often poor.

  In addition, since the said filler should just have at least 2 sort (s) selected from the said titanium-aluminum-type metal compound, a titanium oxide, and an aluminum oxide, if it is a small amount, other metals or An inorganic compound may be included.

The electrical resistivity (specific resistance) of the conductor is preferably lower than, for example, 20 × 10 ⁻⁸ Ω · m, more preferably 15 × 10 ⁻⁸ Ω · m or less, particularly 10 × 10 ⁻⁸ Ω · m. The following is preferable.

  Although the average particle diameter of the filler before firing is not particularly limited, it is preferably 10 μm or less. The reason is that if the filler is fine and uniform, it can be easily dispersed uniformly in the molten copper, and the flow and volatilization of the molten copper can be effectively prevented. For the same reason, it is preferable that the average particle diameter of copper is 10 μm or less. When the average particle size is more than 10 μm, the effect of suppressing copper from being raised in a ball shape especially for a large area pattern such as a mounting pad is diminished, and bleeding and thinning of the wiring are suppressed. The effect will also fade. The average particle size of the filler and copper is more preferably 2 μm or less, further preferably 1 μm or less, and particularly preferably 0.5 μm or less.

  The content of the inorganic compound in the conductor is not particularly limited. For example, when the inorganic compound is mainly composed of titanium oxide and aluminum oxide, the content is 15% by volume to 75% by volume. Is preferred.

  If the amount is less than 15% by volume, the amount of the inorganic compound is reduced, and as a result, the flow and volatilization of the molten copper may not be effectively prevented. On the other hand, if it exceeds 75% by volume, the co-sinterability with the ceramic deteriorates, which is not preferable. In addition, the copper content is too low, and the copper particles cannot be connected in the conductor, resulting in poor conductivity. In consideration of the above, the content of the inorganic compound in the conductor is preferably 15% by volume to 75% by volume as described above, and more preferably 15% by volume to 60% by volume. The volume% or more and 50 volume% or less are the most suitable.

  Further, as another means (means 2) for solving the above-mentioned problem, the ceramic part manufacturing method according to the above means 1, which contains a copper powder and contains at least a titanium-aluminum metal compound powder. A conductor paste preparing step for preparing a conductor paste, and a conductor forming layer formed by printing and applying the conductor paste on a ceramic green sheet containing as a main component a ceramic sintered at a temperature higher than the melting point of copper A forming layer forming step, a stacking step of stacking and integrating the ceramic green sheets on which the conductor forming layer is formed to produce an unsintered laminate, and the unsintered laminate at a temperature at which the ceramic can be sintered. And a co-firing step of firing the ceramic green sheet and the conductor forming layer by heating a body. There is a method.

  The effects of the manufacturing method of the means 2 will be described below. In the conductor paste preparation step of means 2, a conductor paste containing copper powder and containing at least a titanium-aluminum metal compound powder is prepared, and part or all of the metal compound is pyrolyzed in the subsequent simultaneous firing process. By oxidizing, titanium oxide and aluminum oxide are produced. That is, in obtaining a conductor composed of a mixed phase of filler and copper mainly composed of the metal compound, titanium or aluminum is contained in the conductor paste in a non-oxide state instead of an oxide. The reason is that if it is already an oxide at the stage of the conductor paste, it will agglomerate in copper and the dispersibility will deteriorate. In that respect, when it is a non-oxide, it does not aggregate in copper and stable dispersibility can be obtained. Therefore, according to the manufacturing method of the means 2, it is possible to easily and reliably obtain the ceramic component of the means 1 having a low-resistance and suitable-shaped conductor excellent in adhesive strength with the ceramic substrate and co-sinterability.

  In this case, the content of the copper powder is preferably 40% by volume or more and 90% by volume or less, and the content of the titanium-aluminum metal compound powder is preferably 10% by volume or more and 60% by volume or less. If the content of the copper powder is less than 40% by volume or the content of the titanium-aluminum metal compound powder is more than 60% by volume, the co-sinterability with the ceramic is deteriorated, and the copper is contained in the conductor. There is a possibility that the particles cannot be present in a connected state and the conductivity is deteriorated. Conversely, if the content of the copper powder exceeds 90% by volume or the content of the titanium-aluminum-based metal compound powder is less than 10% by volume, the amount of the metal compound decreases, resulting in the flow of molten copper, There is a risk that volatilization cannot be effectively prevented. In addition, if the content of both powders is set in the above preferred range, if all of the titanium-aluminum metal compound is oxidized, the content of titanium oxide and aluminum oxide is 15 volume% or more and 75 volume%. It becomes easy to obtain the following conductors.

  Here, it is preferable that the said conductor paste contains copper powder as a main component, and contains the powder of a titanium-aluminum-type metal compound as an auxiliary component quantitatively smaller than it. In this case, the conductivity of the obtained conductor is increased, and the resistance can be reliably reduced.

  The average particle size of the titanium-aluminum metal compound powder in the conductor paste is not particularly limited, but is preferably 10 μm or less. The reason is that fine and uniform powders are more easily dispersed uniformly in the molten copper, and can effectively prevent the molten copper from flowing and volatilizing. For the same reason, the copper powder preferably has an average particle size of 10 μm or less. The average particle size of these powders is more desirably 2 μm or less, further desirably 1 μm or less, and particularly desirably 0.5 μm or less.

[First embodiment]

  Hereinafter, a ceramic package 10 according to a first embodiment of the present invention and a manufacturing method thereof will be described with reference to FIGS.

  As shown in FIG. 1, the ceramic package 10 of the present embodiment is a wiring board for mounting a semiconductor integrated circuit element such as an IC chip 21 or an optical element such as a VICSEL. The ceramic substrate 11 constituting the ceramic package 10 is a member having a rectangular flat plate shape having an upper surface 12 (substrate surface) and a lower surface 13. The ceramic substrate 11 has a three-layer structure in which three ceramic sintered layers 14, 15 and 16 are laminated. In the present embodiment, the upper ceramic sintered layer 14, the intermediate ceramic sintered layer 15, and the lower ceramic sintered layer 16 are all made of an alumina sintered body. In the present embodiment, a three-layer structure is used, but a two-layer structure may be adopted, or a multilayer structure having four or more layers may be adopted.

  The ceramic substrate 11 includes a cavity 22 that opens on the upper surface 12. The cavity 22 of the present embodiment has a substantially rectangular shape in plan view, but a shape other than the substantially rectangular shape may be employed. The outer dimension of the cavity 22 is set to about 50% to 90% of the outer dimension of the ceramic base 11, and is set to about 65% of the outer dimension of the ceramic base 11 in this embodiment. The depth of the cavity 22 corresponds to the thickness of the upper ceramic sintered layer 14. At two spaced locations on the bottom surface of the cavity 22, an upper surface side mounting pad 23 made of a metallized layer obtained by simultaneous firing with ceramic is formed. The IC chip 21 is bonded onto these upper surface side mounting pads 23 using Ag epoxy resin or Ag-Si resin. The IC chip 21 may be bonded to the upper surface side mounting pad 23 by Au-Au bonding. A nickel layer or a gold layer (both not shown) may be formed on the upper surface side mounting pad 23 as necessary.

  A via conductor 18 is formed at a location corresponding to the upper surface side mounting pad 23 in the intermediate ceramic sintered layer 15. An inner layer conductor pattern 28 made of a metallized layer obtained by co-firing with ceramic is formed at the interface between the intermediate ceramic sintered layer 15 and the lower ceramic sintered layer 16. Each of the conductors 18 is electrically connected to the lower end.

  As shown in FIG. 1, via conductors 19 obtained by co-firing with ceramic are also formed at locations corresponding to the inner conductor pattern 28 in the lower ceramic sintered layer 16. A plurality of lower surface side mounting pads 27 made of a metallized layer obtained by simultaneous firing with ceramic are provided on the outer peripheral portion of the lower surface 13 of the ceramic substrate 11. The lower surface side mounting pads 27 are electrically connected to the lower ends of the via conductors 19 of the lower ceramic sintered layer 16, respectively. These lower surface side mounting pads 27 are bonded to a plurality of substrate side terminals when the ceramic package 10 is mounted on another substrate (on the motherboard) (not shown). The package form is not particularly limited and may be arbitrary. For example, any of BGA (ball grid array), PGA (pin grid array), and LGA (land grid array) may be used.

  In the ceramic package 10 of the present embodiment, the conductors of each part (that is, the via conductors 18 and 19, the upper surface side mounting pad 23, the lower surface side mounting pad 27, and the inner layer conductor pattern 28) are titanium-aluminum metal compound, titanium. It is made of a mixed phase of a filler mainly composed of at least two kinds of inorganic compounds selected from oxides and aluminum oxides and copper. In particular, each portion of the conductor in the present embodiment includes a filler mainly composed of titanium oxide and aluminum oxide generated by thermal decomposition and oxidation of the titanium-aluminum metal compound. Further, the content of these oxides in the conductor is set to be 15 volume% or more and 75 volume% or less.

  Next, a method for manufacturing the ceramic package 10 having the above structure will be described with reference to FIGS.

  First, a ceramic base preparation step for preparing a ceramic green body to be the ceramic base 11 is performed. Specifically, a ceramic powder such as alumina powder, an organic binder, a solvent, a plasticizer, and the like are mixed to prepare a slurry. Then, this slurry is formed into a sheet having a thickness of 100 μm to 300 μm by a conventionally known method (for example, a doctor blade method or a calender roll method), and three ceramic green sheets 64, 65, 66 as shown in FIG. 2 are produced. To do. A cavity 22 having a substantially rectangular shape in plan view is formed through substantially the center of the upper ceramic green sheet 64. The cavity 22 may be formed by a conventionally known punching (punching) process, or may be formed by a technique such as laser processing or drilling.

More specifically, in the present embodiment, an alumina powder having an average particle diameter of 0.8 μm is used, and this is 90% by weight, and the balance thereof is SiO ₂ , MgO, BaO, MnO ₂ , Nb ₂ O ₅ or the like. Mixed. Such a mixed powder was mixed with a butyral binder, a plasticizer, a solvent and the like to form a slurry.

  In the subsequent drilling step, holes 76 that will later become via conductors 18 are formed through the ceramic green sheets 64, 65, 66, which are ceramic unsintered bodies, respectively (see FIG. 3). The hole 76 may be formed by a conventionally known punching (punching) process, or may be formed by a technique such as laser processing or drilling.

  On the other hand, a conductor paste preparation step is performed, and a conductor paste 77 for forming conductors of each part is prepared in advance. Here, a conductor paste 77 containing copper powder as a main component and containing titanium-aluminum metal compound powder is used. The conductor paste 77 contains a binder, a dispersant, a solvent, and the like.

  In the subsequent via filling step, via metallization filling is performed by a conventionally known paste printing apparatus to fill the hole portion 76 with the conductor paste 77 (see FIG. 4). Next, a conductor formation layer forming step is performed, and the conductor paste 77 is printed and applied in a predetermined pattern on the ceramic green sheets 65 and 66 by a screen printing device to form a conductor formation layer 78. Incidentally, the conductor formation layer 78 formed by printing and coating is a portion to be the upper surface side mounting pad 23, the lower surface side mounting pad 27, and the inner layer conductor pattern 28 later.

  In the subsequent lamination process, the intermediate ceramic green sheet 65 and the upper ceramic green sheet 64 are sequentially laminated on the lower ceramic green sheet 66, and a predetermined load is applied in the thickness direction using a conventionally known laminating apparatus, These are pressed and integrated to form an unsintered laminate 10A (see FIG. 5).

  And after degreasing | defatting this laminated body in nitrogen, it baked by the predetermined | prescribed temperature (1200 to 1400 degreeC) which an alumina can sinter in the humidified nitrogen hydrogen mixed gas under the desired oxygen partial pressure. After such a simultaneous firing step, the upper ceramic green sheet 64, the intermediate ceramic green sheet 65, and the lower ceramic green sheet 66 are sintered, and the ceramic substrate 11 having the cavity 22 is obtained. At this time, the conductive paste 77 is simultaneously sintered to form the upper surface side mounting pad 23, the lower surface side mounting pad 27, the inner layer conductor pattern 28, and the via conductor 18. It can be understood that the product in this state is a multi-cavity ceramic package having a structure in which a plurality of product regions to be the ceramic package 10 are arranged vertically and horizontally along the plane direction.

  Furthermore, the multi-cavity ceramic package is divided along break grooves (not shown) and separated into individual pieces (see FIG. 6). Thereafter, the IC chip 21 is accommodated in the cavity 22 and soldering is performed. As a result, the element-equipped ceramic package 10 shown in FIG. 1 is completed.

  Next, the evaluation test performed in this embodiment will be described.

  In this evaluation test, a plurality of types of samples were prepared by changing the material constituting the conductor (see Nos. 1 to 13 in Table 1), and the specific resistance (μΩ · cm) and conductor layer shape (bleeding, copper) Spheroids and warping). The results are shown in Table 1 (see FIG. 7). Here, a test sample having a line-shaped conductor layer having a width of 200 μm and a length of 30 mm and a square conductor layer having a size of 12.5 mm × 12.5 mm was prepared by the above-described procedure.

  About specific resistance, after measuring the resistance value of the said line-shaped conductor layer with a 4-terminal ohmmeter, the value was computed based on the cross-sectional area and wiring length of the said line-shaped conductor layer. If the specific resistance value was 20 μΩ · cm or less, it was determined as “good”. As for the shape of the conductor layer, the conductor layer was visually observed with a magnifying glass, and “◯ (good)” was given if copper was not extruded onto the surface of the conductor layer or the pad portion. In addition, when the firing shrinkage rates of the ceramic and the square conductor layer did not match and the square conductor layer warped by 200 μm or more, it was determined as “x (defect)”.

Here, Sample No. 1, a conductor paste containing 100 parts by volume of copper (Cu) having a particle diameter of 0.5 μm was used to obtain a conductor layer made of only copper. Sample No. 2, a conductor paste including 65 parts by volume of tungsten (W) filler having a particle size of 1.8 μm and 35 parts by volume of copper having a particle size of 0.5 μm is used, and a conductor made of a mixed phase of the filler and copper. A layer was obtained. Sample No. 3, a conductive paste containing 30 parts by volume of alumina (Al ₂ O ₃ ) filler having a particle size of 1.5 μm and 70 parts by volume of copper having a particle size of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 4, a conductor paste containing 30 parts by volume of titanium oxide (TiO ₂ ) filler having a particle size of 2 μm and 70 parts by volume of copper having a particle size of 0.5 μm is used, and a conductor composed of a mixed phase of the filler and copper. A layer was obtained. Sample No. 5, a conductive paste containing 30 parts by volume of an aluminum-nickel metal compound (NiAl) filler having a particle diameter of 7 μm and 70 parts by volume of copper having a particle diameter of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 6, a conductive paste containing 30 parts by volume of an aluminum-cobalt metal compound (CoAl) having a particle size of 6 μm and 70 parts by volume of copper having a particle size of 0.5 μm is used, and the mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 7, a conductive paste containing 20 parts by volume of a titanium-aluminum metal compound (Ti ₃ Al) having a particle size of 9 μm and 80 parts by volume of copper having a particle size of 0.5 μm is used. A conductor layer comprising a mixed phase was obtained. Sample No. 8, a conductive paste containing 10 parts by volume of a titanium-aluminum metal compound (TiAl) filler having a particle diameter of 7 μm and 90 parts by volume of copper having a particle diameter of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 9, a conductive paste containing 20 parts by volume of a titanium-aluminum metal compound (TiAl) filler having a particle diameter of 7 μm and 80 parts by volume of copper having a particle diameter of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 10, a conductive paste containing 30 parts by volume of a titanium-aluminum metal compound (TiAl) having a particle diameter of 7 μm and 70 parts by volume of copper having a particle diameter of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 11, a conductive paste containing 40 parts by volume of a titanium-aluminum metal compound (TiAl) having a particle size of 7 μm and 60 parts by volume of copper having a particle size of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. No. 12, a conductive paste containing 50 parts by volume of a titanium-aluminum metal compound (TiAl) having a particle diameter of 7 μm and 50 parts by volume of copper having a particle diameter of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained. Sample No. 13, a conductive paste containing 60 parts by volume of a titanium-aluminum metal compound (TiAl) having a particle diameter of 7 μm and 40 parts by volume of copper having a particle diameter of 0.5 μm is used, and a mixed phase of the filler and copper is used. A conductor layer was obtained.

  Table 1 shows the metal oxide precipitated in the sintered body after firing, and particularly when the metal oxide is titanium oxide and aluminum oxide, the amount in the sintered body is also shown. I wrote.

  As shown in Table 1 in FIG. 1 (Cu100) and sample no. With respect to 2 (Cu35: W65), bleeding, copper ball-like embossing, and warping were remarkable, and a suitable sample capable of measuring specific resistance could not be obtained.

  Sample No. As for samples 3 and 4, a sample capable of measuring specific resistance could be obtained, but the shape of the conductor layer was poor because bleeding, copper ball-like protrusion and warpage were observed. Further, only one kind of oxide was precipitated in the sintered body.

  Sample No. For 5 and 6, a sample capable of measuring the specific resistance could be obtained, but the measured value was very high. Two kinds of oxides were precipitated in the sintered body, but they were aggregated, and it was assumed that this was the cause of the increase in specific resistance value. In addition, since the occurrence of bleeding, copper ball-like protrusion and warpage was observed, the shape of the conductor layer was bad. That is, sample no. In Nos. 5 and 6, the effect of adding the metal compound was not obtained.

On the other hand, sample No. As for 7 to 13, it was found that a sample capable of measuring specific resistance could be obtained, and the measured value was also low. In particular, sample no. In 7 to 11, the value was considerably lower than 10 × 10 ⁻⁸ Ω · m, and low resistance was reliably achieved as compared with the current product. Also, two types of oxides, titanium oxide and aluminum oxide, were precipitated in the sintered body, but they were not aggregated and existed in a state of being uniformly dispersed in copper. Therefore, it was estimated that this contributed to the reduction of the specific resistance value. In addition, no bleeding, copper ball-like embossing or warping was observed, and the conductor layer shape was good. As described above, sample no. In 7-13, the effect by addition of a metal compound was able to be acquired. In addition, sample No. in a table | surface. Samples marked with * belong to the preferred range of the present invention.

FIG. 8 is a micrograph (SEM photograph) of the conductor layer of a sample (for example, No. 8) that showed good results in the previous evaluation test. In the photograph, the black part is aluminum oxide (Al ₂ O ₃ ), the light gray part is titanium oxide (TiO ₂ ), and the white part is copper (Cu). According to this, it can be seen that Al ₂ O ₃ and TiO ₂ are uniformly dispersed in Cu without forming an agglomerated part (a lump having a diameter of 10 μm or more). It can also be seen that there are no voids in the sintered body. In addition, the above tendency is sample No. The same was true for 7, 9-13.

FIG. 8 shows data obtained by examining the element distribution of eight conductor layers by energy dispersive X-ray analysis. According to this, the largest peak is recognized at Cu, and a small peak is recognized at Al ₂ O ₃ and TiO ₂ . Therefore, it was found that most of the titanium-aluminum metal compound (TiAl) was pyrolyzed and oxidized to Al ₂ O ₃ and TiO ₂ after firing.

  Therefore, according to the present embodiment, the following effects can be obtained.

  (1) In the ceramic package 10 of this embodiment, since the conductor of each part is formed including copper, the resistance is lower than that of a conventional conductor mainly composed of tungsten. Moreover, since the conductor of each part consists of a mixed phase of a filler mainly composed of at least two kinds of inorganic compounds selected from a titanium-aluminum metal compound, titanium oxide and aluminum oxide, co-firing Sometimes the flow and volatilization of the molten copper is prevented. As a result, copper in the conductor is held in that position, and voids in the conductor and protrusion of the conductor from the ceramic portion are prevented. As a result, a conductor having a relatively favorable shape can be obtained.

  From the above, according to the present embodiment, the ceramic base 11 has excellent mechanical strength and little deformation, and has a low resistance and suitable shape with excellent adhesive strength and simultaneous sintering with the ceramic base 11. A ceramic package 10 having a conductor can be obtained.

Further, in the manufacturing method of this embodiment, when obtaining a conductor having a predetermined composition, titanium or aluminum is contained in the conductor paste 77 in a non-oxide state instead of an oxide, and in this state, co-firing with a ceramic is performed. Like to do. For this reason, a low-resistance and suitable-shaped conductor excellent in adhesive strength with the ceramic substrate 11 and co-sinterability can be obtained. Therefore, according to this manufacturing method, the ceramic package 10 having excellent characteristics as described above can be obtained easily and reliably.
[Second Embodiment]

  Next, a ceramic capacitor built-in wiring board 110 according to a second embodiment embodying the present invention will be described with reference to FIGS.

  As shown in FIG. 10, the ceramic capacitor built-in wiring board 110 (ceramic component) of the present embodiment is a wiring board for mounting an IC chip for MPU. The wiring substrate 110 includes a flat core substrate 111 made of glass epoxy, a ceramic capacitor 201, and build-up layers 131 and 132. Through-hole conductors 116 are formed at a plurality of locations on the core substrate 111. The through-hole conductor 116 connects and conducts the core first main surface 112 side and the core second main surface 113 side of the core substrate 111. The inside of the through-hole conductor 116 is filled with a closing body 117 such as an epoxy resin. Further, a conductor layer 141 made of copper is patterned on the core first main surface 112 and the core second main surface 113 of the core substrate 111, and each conductor layer 141 is electrically connected to the through-hole conductor 116. It is connected to the.

  The buildup layer 131 formed on the core first main surface 112 side of the core substrate 111 includes a core first main surface side conductor layer 142 made of copper and resin insulating layers 133 and 135 made of epoxy resin (so-called interlayer insulating layer). Are stacked. Terminal pads 144 are formed in an array at a plurality of locations on the surface of the resin insulating layer 135. The surface of the resin insulating layer 135 is almost entirely covered with the solder resist 137. An opening 146 that exposes the terminal pad 144 is formed at a predetermined location of the solder resist 137. A plurality of solder bumps 145 are disposed on the surface of the terminal pad 144. Each solder bump 145 is electrically connected to the power supply electrode 122 and the signal line electrode 125 of the IC chip 121 (semiconductor integrated circuit element). Each terminal pad 144 and each solder bump 145 are located in a region immediately above the ceramic capacitor 201 in the buildup layer 131, and this region becomes the semiconductor element mounting portion 123. A via conductor 150 is provided in the resin insulation layer 133, and a via conductor 143 is provided in the resin insulation layer 135. Most of these via conductors 143 and 150 are arranged coaxially, and the conductor layers 141 and 142 and the terminal pads 144 are electrically connected to each other through them.

  The buildup layer 132 formed on the core second main surface 113 side of the core substrate 111 has substantially the same structure as the buildup layer 131 described above. That is, the buildup layer 132 has a structure in which a core second main surface side conductor layer 142 made of copper and resin insulating layers 134 and 136 made of epoxy resin are laminated. BGA pads 148 are formed in a lattice pattern at a plurality of locations on the lower surface of the resin insulating layer 136. Further, the lower surface of the resin insulating layer 136 is almost entirely covered with a solder resist 138. An opening 140 for exposing the BGA pad 148 is formed at a predetermined portion of the solder resist 138. On the surface of the BGA pad 148, a plurality of solder bumps 149 are provided for electrical connection with a mother board (not shown). Then, with each solder bump 149, the wiring board 110 shown in FIG. 10 is mounted on a mother board (not shown). A via conductor 147 is provided in the resin insulating layer 134, and a via conductor 151 is provided in the resin insulating layer 136. In the present embodiment, most of the via conductors 147 and 151 are arranged coaxially, and the conductor layers 141 and 142 and the BGA pad 148 are electrically connected to each other via the via conductors 147 and 151.

  The core substrate 111 has a housing hole 190 that is rectangular in a plan view and opens at the center of the core first main surface 112 and the center of the core second main surface 113. That is, the accommodation hole 190 is a through hole. The ceramic capacitor 201 shown in FIG. 11 is housed in the housing hole 190 in an embedded state. The ceramic capacitor 201 has a main surface 202 (upper surface in FIG. 11) facing the same side as the first core main surface 112 of the core substrate 111 and a back surface 203 (lower surface in FIG. 11) of the core second of the core substrate 111. The main surface 113 is accommodated in the same direction. The ceramic capacitor 201 of the present embodiment has a rectangular flat plate shape of 12.0 mm long × 12.0 mm wide × 0.75 mm thick.

  Further, a gap 192 between the inner surface of the accommodation hole 191 and the side surface of the ceramic capacitor 201 is filled with a resin filler 195 made of a polymer material (thermosetting resin in the present embodiment). The resin filler 195 has a function of fixing the ceramic capacitor 201 to the core substrate 111 and absorbing the deformation of the ceramic capacitor 201 and the core substrate 111 in the surface direction and the thickness direction by its own elastic deformation. .

  As shown in FIGS. 10 and 11, the ceramic capacitor 201 of the present embodiment is a so-called via array type multilayer ceramic capacitor. A ceramic sintered body 204 (capacitor main body) constituting the ceramic capacitor 201 is a plate-like object having a main surface 202 and a back surface 203. The ceramic sintered body 204 has a structure in which first inner layer electrodes 241 (inner layer electrodes) and second inner layer electrodes 242 (inner layer electrodes) are alternately stacked via ceramic dielectrics 205. In the present embodiment, the dielectric 205 is made of a sintered body mainly composed of barium titanate, which is a kind of high dielectric constant ceramic. The first inner layer electrode 241 and the second inner layer electrode 242 are layers formed in a predetermined pattern, and are disposed every other layer inside the ceramic sintered body 204. The first inner layer electrode 241 and the second inner layer electrode 242 are a mixed phase of a filler mainly composed of at least two inorganic compounds selected from titanium-aluminum-based metal compounds, titanium oxides, and aluminum oxides, and copper. Specifically, it consists of a mixed phase of copper and a filler mainly composed of titanium oxide and aluminum oxide generated by thermal decomposition and oxidation of a titanium-aluminum-based metal compound.

  A number of via holes 230 (diameter of about 100 μm) are formed in the ceramic sintered body 204. These via holes 230 extend along the thickness direction of the ceramic sintered body 204, penetrate the ceramic sintered body 204, and are arranged in a lattice shape (array shape) over the entire surface. In the present embodiment, for convenience of explanation, the via holes 230 are illustrated in 4 rows × 4 rows, but there are actually more rows. In each via hole 230, a plurality of via conductors 231 and 232 that penetrate between the main surface 202 and the back surface 203 of the ceramic sintered body 204 are formed. The plurality of via conductors 231 and 232 have the same metal composition as that of the first inner layer electrode 241 and the second inner layer electrode 242, and titanium oxide generated by thermal decomposition and oxidation of the titanium-aluminum metal compound. And a mixed phase of copper and a filler mainly composed of an aluminum oxide. Each first via conductor 231 penetrates each first inner layer electrode 241 and electrically connects them to each other. Each second via conductor 232 penetrates each second inner layer electrode 242 and electrically connects them to each other.

  On the main surface 202 of the ceramic sintered body 204, a plurality of first external electrodes 211 and 212 are projected. In addition, a plurality of second external electrodes 221 and 222 protrude from the back surface 203 of the ceramic sintered body 204. The first external electrodes 211 and 212 on the main surface 202 side are electrically connected to the via conductor 143 on the buildup layer 131 side. On the other hand, the second external electrodes 221 and 222 on the back surface 203 side are electrically connected to the via conductor 150 on the buildup layer 132 side. Further, the substantially central portion of the bottom surface of the first external electrodes 211 and 212 is directly connected to the end surface of the via conductors 231 and 232 on the main surface 202 side, and the substantially central portion of the bottom surface of the second external electrodes 221 and 222 is The via conductors 231 and 232 are directly connected to the end surface on the back surface 203 side. Therefore, the external electrodes 211 and 221 are electrically connected to the via conductor 231 and the first inner layer electrode 241, and the external electrodes 212 and 222 are electrically connected to the via conductor 232 and the second inner layer electrode 242.

  The first external electrodes 211 and 212 also have the same metal composition as the first inner layer electrode 241 and the second inner layer electrode 242, and titanium generated by thermal decomposition and oxidation of the titanium-aluminum metal compound. It consists of a mixed phase of copper and filler mainly composed of oxide and aluminum oxide. Copper plating is applied to the entire surface of the first external electrodes 211 and 212. The shape of the first external electrodes 211 and 212 when viewed from the direction perpendicular to the main surface 202 (part thickness direction) is substantially circular. The second external electrodes 221 and 222 have the same structure and shape.

  When power is applied to the second external electrodes 221 and 222 from the mother board side (not shown) via the via conductors 147 and 151 and a voltage is applied between the first inner layer electrode 241 and the second inner layer electrode 242, for example, For example, negative charges are accumulated in the second inner layer electrode 242. As a result, the ceramic capacitor 201 functions as a capacitor. In the ceramic capacitor 201, the first via conductors 231 and the second via conductors 232 are alternately arranged adjacent to each other, and the directions of the currents flowing through the first via conductors 231 and the second via conductors 232 are opposite to each other. It is set to face. Thereby, the inductance component is reduced.

  The first via conductor 231 and the second via conductor 232 are electrically connected to the power supply electrode 122 of the IC chip 121 mounted on the wiring board 110 via the via conductors 143 and 150 of the buildup layer 131. It has come to be. That is, the first via conductor 231 and the second via conductor 232 constitute part of the power supply and ground in the wiring board 110. Therefore, since such a connection relationship is set, the capacitor 201 of the present embodiment functions as a decoupling capacitor. On the other hand, the signal line electrode 125 of the IC chip 121 is electrically connected to the motherboard via the through-hole conductor 116 of the core substrate 111 without flowing through the conductor portion in the capacitor 201.

  And according to the ceramic capacitor 201 of the present embodiment having the above-described structure, it has a ceramic sintered body 204 (ceramic substrate) having excellent mechanical strength and little deformation, It is possible to have a conductor having a low resistance and a suitable shape excellent in adhesive strength and co-sinterability. Therefore, according to the present embodiment, high capacity, high reliability, low inductance, and low electrical resistance can be achieved, and a via array type multilayer ceramic capacitor 201 suitable for decoupling applications can be realized. Further, in the present embodiment, since such an excellent capacitor 201 is built in to constitute the capacitor built-in wiring board 110, the capability of the MPU IC chip 121 mounted thereon can be sufficiently drawn. Therefore, an excellent semiconductor device can be realized.

  In addition, you may change embodiment of this invention as follows.

  In the first embodiment, the present invention is embodied in the ceramic package 10 (ceramic wiring board). In the second embodiment, the present invention is embodied in the via array type multilayer ceramic capacitor 201. However, the present invention is embodied in other ceramic parts. Also good.

  In the second embodiment, the metal composition of the conductor of each part is a mixture of a filler mainly composed of titanium oxide and aluminum oxide produced by thermal decomposition of a titanium-aluminum metal compound and copper. It consisted of phases. However, the present invention is not limited to this. For example, the metal composition of the inner layer electrodes 241 and 242 and the outer electrodes 211, 212, 221, and 222 may be changed to another metal that can be co-fired with barium titanate such as nickel. Good.

  In the second embodiment, external electrodes 211, 212, 221, and 222 are provided on both the main surface side end portions and the back surface side end portions of the via conductors 231 and 232 of the via array type multilayer ceramic capacitor 201, respectively. However, the external electrodes 211, 212, 221, and 222 may be provided only at the end on the main surface side.

  In the second embodiment, the ceramic capacitor 201 is disposed in the core substrate 111, but it may be disposed in the buildup layers 131 and 132. Further, the ceramic capacitor 201 is not limited to the wiring board built-in type, and may be a wiring board surface mounting type.

  Next, in addition to the technical ideas described in the claims, the technical ideas grasped by the embodiments described above are listed below.

  (1) A ceramic base made of a dielectric material mainly composed of barium titanate, which has a plate shape having a main surface and a back surface and is sintered at a temperature higher than the melting point of copper, and is laminated via the ceramic base. A plurality of inner layer electrodes, a plurality of via conductors formed in a plurality of via holes extending along the thickness direction of the ceramic substrate, and connected to the plurality of inner layer electrodes, and at least in the plurality of via conductors A via array type multilayer ceramic capacitor, wherein the plurality of via conductors are arranged in an array as a whole, wherein the plurality of inner layer electrodes are provided with a plurality of external electrodes arranged so as to be connected to end portions on the main surface side , At least one of the plurality of via conductors and the plurality of external electrodes includes a titanium-aluminum metal compound, a titanium oxide, and an aluminum acid. At least two via array type multilayer ceramic capacitor of the inorganic compound consists of a mixed phase of the filler and copper mainly selected from among objects.

  (2) The via array type multilayer ceramic according to the above idea 1, wherein the titanium oxide and the aluminum oxide are produced by thermal decomposition and oxidation of the titanium-aluminum metal compound. Capacitor.

  (3) A capacitor built-in wiring board in which the capacitor according to the above idea 1 or 2 is built.

  (4) The capacitor is a decoupling capacitor, and the via conductor is electrically connected to a power supply electrode of a semiconductor integrated circuit element to be mounted on the wiring board. The wiring board with a built-in capacitor according to thought 3.

1 is a schematic cross-sectional view showing a ceramic package of a first embodiment embodying the present invention. The schematic sectional drawing for demonstrating the manufacturing procedure of the ceramic package of 1st Embodiment. The schematic sectional drawing for demonstrating a manufacture procedure similarly. The schematic sectional drawing for demonstrating a manufacture procedure similarly. The schematic sectional drawing for demonstrating a manufacture procedure similarly. The schematic sectional drawing for demonstrating a manufacture procedure similarly. The table | surface which described the result of the evaluation test. The SEM photograph of a conductor part. Data showing the element distribution survey results of conductor parts. Sectional drawing which shows the wiring board which incorporated the via array type multilayer ceramic capacitor of 2nd Embodiment which actualized this invention. Sectional schematic which shows the via array type multilayer ceramic capacitor of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Ceramic package as ceramic component (ceramic wiring board) 10A ... Unsintered laminated body 11 ... Ceramic substrate 18, 19 ... Via conductor as conductor 23 ... Mounting pad as conductor 27 ... Mounting pad as conductor 28 ... Conductor Inner layer conductor pattern 64, 65, 66 as ceramic green sheet 76 ... via hole 77 ... conductor paste 78 ... conductor forming layer 201 ... via array type multilayer ceramic capacitor as ceramic component 204 ... ceramic sintered body 211 as ceramic substrate, 212: First external electrode as a conductor 221, 222: Second external electrode as a conductor 231: First via conductor as a conductor 232: Second via conductor as a conductor 241: First inner layer electrode as a conductor 242: Conductor Second inner layer electrode as

Claims (9)

In a ceramic part in which a conductor is formed on a ceramic base mainly composed of a ceramic that is sintered at a temperature higher than the melting point of copper,
The conductor is made of a mixed phase of a filler mainly composed of at least two inorganic compounds selected from titanium-aluminum-based metal compounds, titanium oxides, and aluminum oxides, and copper. .   2. The ceramic component according to claim 1, wherein the titanium oxide and the aluminum oxide are produced by thermal decomposition and oxidation of the titanium-aluminum metal compound.   The inorganic compound is mainly composed of the titanium oxide and the aluminum oxide, and the content of the inorganic compound in the conductor is 15% by volume or more and 75% by volume or less. Ceramic parts.   4. The ceramic component according to claim 1, wherein the filler has an average particle size of 10 μm or less. 5. 5. The ceramic component according to claim 1, wherein the conductor has an electric resistivity of 20 × 10 ⁻⁸ Ω · m or less.   2. The ceramic component according to claim 1, wherein the ceramic component is a ceramic wiring board including an inner layer conductor pattern and a via conductor formed inside the ceramic base, and a mounting pad formed on the surface of the ceramic base. The ceramic component according to any one of 1 to 5.   The ceramic component has a plate shape having a main surface and a back surface, and a ceramic substrate in which a plurality of inner layer electrodes are laminated via a dielectric material mainly composed of barium titanate, and a thickness direction of the ceramic substrate And a plurality of via conductors connected to the plurality of inner layer electrodes, and arranged to connect to at least the main surface side end portions of the plurality of via conductors. 6. The ceramic according to claim 1, wherein the ceramic is a via array type multilayer ceramic capacitor including a plurality of external electrodes, wherein the plurality of via conductors are arranged in an array as a whole. parts. A method for manufacturing a ceramic component according to any one of claims 1 to 7,
A conductor paste preparation step for preparing a conductor paste containing copper powder and containing at least a titanium-aluminum metal compound powder;
A conductor forming layer forming step of forming a conductor forming layer by printing and applying the conductor paste on a ceramic green sheet containing as a main component a ceramic sintered at a temperature higher than the melting point of copper;
A lamination step of laminating and integrating the ceramic green sheets on which the conductor forming layer is formed, and producing an unsintered laminate;
A method of manufacturing a ceramic part, comprising: a simultaneous firing step of heating the green laminate to a temperature at which the ceramic can be sintered to fire the ceramic green sheet and the conductor forming layer.   The content of the copper powder is 40% by volume or more and 90% by volume or less, and the content of the titanium-aluminum metal compound powder is 10% by volume or more and 60% by volume or less. The manufacturing method of the ceramic component of description.