JP3387189B2 - Ceramic substrate and its manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic substrate on which semiconductor elements, LSIs, chip parts, etc. are mounted and a method for manufacturing the same.

[0002]

2. Description of the Related Art The substrate of a conventional ceramic chip carrier has a plurality of external connection pads on the four sides of the substrate. These external connection pads are formed from the side surface of the substrate to the back surface of the substrate. In recent years, substrates having external connection bumps arranged in a lattice pattern on the back surface of the ceramic substrate have also appeared. These ceramic chip carriers can be mounted on a printed circuit board with high density.

The mounting of the ceramic chip carrier on the printed board (mother board) is performed by the following method. The paste-like solder is printed on desired terminals provided on the printed circuit board. The ceramic chip carrier is arranged so that the external connection terminals provided on the back surface of the ceramic chip carrier are in contact with the terminals on which the paste-like solder is printed. Then, by reflowing the solder, the external connection terminals provided on the back surface of the ceramic chip carrier are soldered to desired terminals provided on the printed board.

[0004]

The bumps for external connection of the conventional ceramic chip carrier are formed after the ceramic substrate is manufactured. Therefore, there is a problem that the manufacturing cost of the ceramic chip carrier is high. Further, in the method of individually forming the plurality of external connection bumps, there is a problem that the external connection bumps have different heights, sizes and shapes. If the bumps for external connection have different heights, the bumps with low bumps are likely to be defective in connection with the printed circuit board.

Further, conventionally, there has been no method for forming bumps for external connection having a sufficient height. As a result, since the substrate of the ceramic chip carrier and the printed circuit board are very close to each other, there is a problem that solder bridging occurs in the solder reflow process and a short circuit occurs between the electrodes. Further, when the coefficient of thermal expansion of the substrate of the ceramic chip carrier and the coefficient of thermal expansion of the printed circuit board on which the ceramic chip carrier is mounted are different, there is a problem that the connection portion is broken due to thermal stress.

To solve the above-mentioned problem of solder bridge, Japanese Patent Laid-Open No. 61-188942 discloses a method of preventing the solder bridge by providing damming means made of an electrically insulating material around the solder connection portion. Disclosure. However, this method has a problem that the structure is complicated and the manufacturing cost is high.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a ceramic substrate which is less likely to cause a solder bridge and has high reliability, and a method for manufacturing the same. .

[0008]

A method for manufacturing a ceramic substrate according to the present invention is a method for manufacturing a ceramic substrate having a plurality of protruding electrodes, and is provided on at least one surface of a green sheet laminate having an upper surface and a lower surface. To the protruding electrode type
The protruding electrode type having a plurality of holes using a layering paste
By printing a layered layer, filling the plurality of holes in the protruding electrode forming layer with a protruding electrode forming paste, baking the green sheet laminate, and removing the protruding electrode forming layer. And a step of forming the plurality of protruding electrodes from the fired paste for forming protruding electrodes, thereby achieving the above object.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014] In one embodiment, before the firing step, the green sheet is used to remove organic substances contained in the green sheet laminate, the protruding electrode forming paste, and the protruding electrode forming layer paste. The method further includes a step of heat-treating the laminate, the protruding electrode forming paste, and the protruding electrode forming layer paste, and a step of reducing the protruding electrode forming paste.

In one embodiment, before the step of providing the protruding electrode forming layer, a substrate forming paste is printed on at least one surface of the green sheet laminate to form a substrate forming paste layer. The method further includes the step of forming.

[0016] In one embodiment, the paste for forming the protruding electrode layer contains an inorganic component which is not sintered at the firing temperature of the laminate firing step as a main component.

Further, in one embodiment, the paste for forming a protruding electrode is formed of Al ₂ O ₃ , MgO, ZrO ₂ , Ti.
It contains at least one component selected from the group consisting of O ₂ , BeO, and BN.

In one embodiment, the bump electrode forming paste is a conductor paste containing at least one component selected from the group consisting of Ag, Pd, Pt, and Cu.

Further, in one embodiment, the bump electrode forming paste is a metal oxide paste containing CuO as a main component.

Further, in one embodiment, the plurality of protruding electrodes are columnar. In one embodiment, a method of manufacturing a ceramic substrate having a plurality of protruding electrodes, the method comprising providing a protruding electrode forming layer having a plurality of holes on at least one surface of a ceramic substrate having an upper surface and a lower surface. A step of filling the plurality of holes of the bump electrode forming layer with a paste for forming a bump electrode, a firing step of firing the ceramic substrate, and a step of firing the protrusion by removing the bump electrode forming layer. Forming a plurality of protruding electrodes from the electrode forming paste.

In one embodiment, the step of providing the protruding electrode forming layer includes the step of forming the plurality of holes in at least one protruding electrode forming layer green sheet, and the forming of the at least one protruding electrode forming layer. Providing a layer green sheet on the at least one surface of the ceramic substrate.

In one embodiment, before the firing step, the protruding electrode forming layer green sheet and the protruding electrode forming layer green sheet are formed in order to remove organic substances contained in the protruding electrode forming layer green sheet and the protruding electrode forming paste. And a step of heat-treating the protruding electrode forming paste and a step of reducing the protruding electrode forming paste.

Further, in one embodiment, the green sheet for forming a protruding electrode contains an inorganic component which is not sintered at the firing temperature of the firing step as a main component.

[0024] In one embodiment, the green sheet for forming the bump electrode is made of Al ₂ O ₃ , MgO, ZrO ₂ ,
It contains at least one component selected from the group consisting of TiO ₂ , BeO, and BN.

In one embodiment, the step of providing the protruding electrode forming layer includes the step of forming the plurality of holes on the at least one surface of the ceramic substrate by using a protruding electrode forming layer paste. The step of printing the forming layer is included.

In one embodiment, before the firing step, the bump electrode forming paste and the protrusions are formed in order to remove organic substances contained in the bump electrode forming paste and the bump electrode forming layer paste. The method further includes a step of heat-treating the electrode forming layer paste and a step of reducing the protruding electrode forming paste.

In one embodiment, before forming the protruding electrode forming layer, a substrate forming paste layer is formed by printing a substrate forming paste on at least one surface of the ceramic substrate. The step of performing is further included.

In one embodiment, the bump electrode forming layer paste contains an inorganic component which is not sintered at the firing temperature of the laminated body firing step as a main component.

In one embodiment, the paste for forming a protruding electrode is formed of Al ₂ O ₃ , MgO, ZrO ₂ , Ti.
It contains at least one component selected from the group consisting of O ₂ , BeO, and BN.

In one embodiment, the bump electrode forming paste is a conductor paste containing at least one component selected from the group consisting of Ag, Pd, Pt, and Cu.

In one embodiment, the bump electrode forming paste is a metal oxide paste containing CuO as a main component.

[0032]

[0033]

[0034]

The plurality of projecting electrodes provided on the ceramic substrate of the present invention are obtained by filling the plurality of holes provided in the projecting electrode forming layer with the projecting electrode forming paste and firing the projecting electrode forming paste. To be By controlling the thickness of the protruding electrode forming layer, the height of the protruding electrode can be controlled. Further, it becomes possible to obtain a plurality of protruding electrodes having a uniform height. Furthermore, the size, shape, and arrangement of the protruding electrodes can be controlled by changing the size, shape, and arrangement of the holes in the protruding electrode forming layer. Further, by forming the protruding electrode forming layer on the substrate forming green sheet and filling the protruding electrode forming paste, it becomes possible to simultaneously fire the substrate forming green sheet and the protruding electrode forming paste. The protruding electrode can be easily formed in the substrate manufacturing process. Furthermore, by using a material that does not sinter the protruding electrode forming layer at the temperature at which the substrate forming green sheet and the protruding electrode forming paste are fired, it becomes possible to easily remove the protruding electrode forming layer, and it is possible to easily Electrodes can be formed.

Since the height of the plurality of protruding electrodes of the ceramic substrate of the present invention is uniform, it is possible to prevent defective connection with the printed circuit board. Further, the ceramic substrate of the present invention,
Since the bump electrode has a height higher than that of the conventional bump electrode, it is possible to prevent the occurrence of a solder bridge in the solder reflow process. Furthermore, since the protruding electrode having a height higher than that of the conventional protruding electrode relieves the thermal stress generated between the ceramic substrate and the printed board, it is possible to suppress the breakage of the joint portion.

[0036]

EXAMPLES The present invention will be described below with reference to examples.

(Embodiment 1) FIG. 1 shows a perspective view of a ceramic substrate having protruding electrodes for external connection obtained in the present embodiment as seen from below the ceramic substrate. The ceramic substrate of the present invention has, on the surface of the substrate 2, a columnar protruding electrode 1 for external connection having a sufficient height and having a uniform height, shape and size.

First, a method of manufacturing the ceramic substrate of the present invention will be described. Hereinafter, in the examples, the present invention will be described by taking a substrate for low temperature sintering as an example, but the present invention is not limited thereto.

As the glass / ceramic of the substrate material, a composition (MLS-19, manufactured by Nippon Electric Glass Co., Ltd.) in which lead borosilicate glass powder and alumina powder as a ceramic material were mixed in a weight ratio of 50:50 was used. This glass-ceramic powder was used as an inorganic component, polyvinyl butyral as an organic binder, di-n-butyl phthalate as a plasticizer, and a mixed solution of toluene and isopropyl alcohol (30:70 weight ratio) as a solvent to form a slurry.

This slurry was formed into a sheet on an organic film by the doctor blade method. As an organic film,
A polymer film such as a PET film can be widely used. Dry the organic film coated with the slurry,
It was punched into a desired size to obtain a green sheet for forming a substrate. Furthermore, a via hole was formed in the substrate forming green sheet as needed. For these film formation, drying, and via hole processing, a known apparatus for continuously performing these steps was used.

The following steps will be described with reference to FIG. FIG. 2 is a diagram showing steps of the method for manufacturing a ceramic substrate of the present invention. Wiring pattern formation and via hole filling printing were performed by screen printing using Ag paste, which is a conductor paste, on the substrate forming green sheet. The inorganic component of the Ag paste for wiring formation is A
g glass frit (GA-9 glass powder, manufactured by Nippon Electric Glass Co., Ltd.) for obtaining adhesive strength to g powder (average particle size 1 μm)
An average particle size of 2.5 μm) was added to 5 wt%.
To the above inorganic components, PVB as an organic binder and a vehicle dissolved in terpineol were added and mixed so as to have an appropriate viscosity by a three-stage roll to obtain a wiring forming Ag paste. The Ag paste for filling the via hole
The Ag paste for wiring formation was further added with 15% by weight of the above glass-ceramic powder as an inorganic component.

Next, a method for manufacturing the green sheet for the protruding electrode forming layer will be described. Alumina powder (manufactured by Sumitomo Chemical Co., Ltd., ALM-41, average particle size 1.9) was used as an inorganic component for the green sheet for the protruding electrode forming layer that did not sinter.
μm) was used. Ethyl cellulose, which is an organic binder, and a vehicle dissolved in terpineol were added to the above inorganic components to obtain a slurry. A sheet was formed on the organic film by the doctor blade method using the obtained slurry. A hole for forming a protruding electrode was opened in the obtained sheet to obtain a green sheet for a protruding electrode forming layer. Similar to the substrate forming green sheet, the holes formed in the protruding electrode forming layer green sheet were filled with the above via hole filling Ag paste. That is, a via hole filling Ag paste was used as the bump electrode forming paste.

A predetermined number of the green sheets for forming the substrate and the green sheet for forming the protruding electrode forming layer are stacked so that the green sheet for forming the protruding electrode forming layer is the outermost layer, and thermocompression bonding is performed in this state to form a green sheet laminated body. Was formed.
The thermocompression bonding conditions are a temperature of 80 ° C. and a pressure of 200 Kg / cm ^2.
Met. The thickness of the substrate forming green sheet and the protruding electrode forming layer green sheet was about 200 μm. FIG. 3 shows a cross-sectional structure of the obtained laminate. The laminated body includes a green sheet layer 3 for forming a substrate having a wiring pattern 5 and a green sheet layer 4 for forming a protruding electrode having a protruding electrode 6.

Next, the obtained laminated body is placed on a 96% alumina substrate and baked. A belt furnace is used for firing in air,
It was carried out at 900 ° C. for 1 hour. The holding time at 900 ° C. was about 12 minutes.

The alumina of the green sheet for the protruding electrode forming layer of the laminate does not sinter at 900 ° C. As a result, the unbaked alumina layer was removed cleanly by ultrasonically cleaning the laminated body in a butyl acetate solvent after firing,
The protruding electrodes could be formed from the sintered protruding electrode forming paste. FIG. 4 shows a cross-sectional view of a ceramic substrate obtained by removing the alumina layer, which is the green sheet for the protruding electrode forming layer. The ceramic substrate of this embodiment has a protruding electrode 6 for external connection on the surface of a substrate 7 having a wiring pattern 5.

In the above example, the protruding electrodes are formed on one surface of the ceramic substrate, but the protruding electrodes may be formed on both surfaces of the ceramic substrate. FIG. 5 shows a cross section of a laminate having the green sheet 4 for forming the protruding electrodes on both sides of the green sheet 7 for forming a substrate. By firing the laminate shown in FIG. 5 and removing the alumina layer of the green sheet for forming the protruding electrodes, a ceramic substrate having protruding electrodes on both sides is obtained.

Further, in the case where the protruding electrodes are formed on one surface of the ceramic substrate, as shown in FIG. 6, the green sheet 4a made of only alumina and the protruding electrode forming layer green sheet 4 are used to form the substrate forming green sheet 3. The use of a laminated body having a structure sandwiching between can prevent deformation such as warpage of the substrate during the sintering process. FIG. 6 shows a cross section of a laminate used for manufacturing the ceramic substrate obtained in this example. This laminated body has a substrate forming green sheet 3 between a protruding electrode forming layer green sheet 4 and a green sheet 4a made of only alumina.

Example 2 In this example, the protruding electrode forming layer was formed by using the protruding electrode forming layer paste instead of the protruding electrode forming layer green sheet of Example 1. First, in the same manner as in Example 1, a green sheet for forming a substrate was produced. A predetermined number of printed wiring patterns and via holes were stacked on the substrate forming green sheets and thermocompression bonded to form a green sheet laminate. The thermocompression bonding conditions were a temperature of 80 ° C. and a pressure of 200 Kg / cm ² . The thickness of the green sheet for substrate formation is about 200μ
It was m.

Next, a paste for forming a protruding electrode was prepared. Alumina powder (manufactured by Sumitomo Chemical Co., Ltd., ALM-4) as an inorganic component of the material for the paste for forming the protruding electrode layer.
1, the average particle size was 1.9 μm). Ethyl cellulose, which is an organic binder, and a vehicle dissolved in terpineol were added to the above alumina powder and mixed by a three-stage roll so as to have an appropriate viscosity (30 Pa.s) to obtain a paste for forming a protruding electrode layer. A protrusion forming layer having a plurality of holes is printed on one surface of the laminate of the green sheets for a substrate by using the paste for forming a protruding electrode, and the paste on the other surface is coated with the paste for forming a protruding electrode. The pattern was printed. A screen plate having a mesh number of 200 mesh and an emulsion thickness of 30 μm was used for the paste electrode forming layer paste printing, and the printing was performed twice. The thickness of the obtained paste electrode forming layer paste layer was about 100 μm.

The laminate printed with the paste for forming the protruding electrodes was dried at 50 ° C. for 10 minutes. Next, the holes formed by the bump electrode forming layer paste were filled with a conductor paste and dried at 50 ° C. for 10 minutes. FIG. 7 shows a cross-sectional view of the laminated body obtained in this example. This laminated body includes a paste layer 8 for a protruding electrode forming layer, a wiring pattern 9, a protruding electrode 10,
It has a substrate-forming green sheet layer 11. The part of the surface of the laminated body not covered with the alumina paste was cut and removed so that the entire surface of the laminated body was covered with the alumina paste. As a result, the structure of the laminated body becomes symmetrical, and deformation in the firing process can be suppressed.

Next, the obtained laminated body was fired in air at 900 ° C. for 1 hour using a belt furnace to obtain a sintered body.
The holding time at 900 ° C. was about 12 minutes.

Alumina, which is the main component of the bump electrode forming layer paste on the surface of the laminate, does not sinter at 900 ° C.
Therefore, by ultrasonically cleaning the fired laminate in a butyl acetate solvent, the paste layer for the protruding electrode forming layer was completely removed, and the protruding electrode made of a sintered body of the conductor paste could be formed. .

Example 3 In this example, a CuO paste, which is a metal oxide paste, was used to form a wiring pattern on a green sheet and fill a via hole. The substrate forming green sheet and the protruding electrode forming layer green sheet were prepared in the same manner as in Example 1. As the inorganic component of the CuO paste for forming the wiring, CuO powder (average particle size 3 μm) and glass frit (LS-0803 glass powder manufactured by Nippon Electric Glass Co., average particle size 2.5 μm) for increasing the adhesive strength are used as CuO. 3wt for powder
% Was used. Ethyl cellulose as an organic binder and a vehicle dissolved in terpineol were added to the above inorganic components and mixed with a three-stage roll so as to have an appropriate viscosity to obtain a CuO paste for wiring formation. The CuO paste for filling via holes is CuO for wiring formation.
The paste was further prepared by adding 15% by weight of the glass-ceramic powder used in Example 1. A hole was opened in the green sheet for forming the protruding electrode, and the hole was filled with a CuO paste for filling a via hole by a screen printing method. That is, the CuO paste for filling the via holes was used as the paste for forming the protruding electrodes.

A predetermined number of substrate forming green sheets and protruding electrode forming layer green sheets were stacked so that the protruding electrode forming layer green sheet was the outermost layer, and thermocompression bonding was performed to form a laminate. The thermocompression bonding conditions were a temperature of 80 ° C. and a pressure of 200 Kg / cm ² . The thickness of each of the substrate forming green sheet and the protruding electrode forming layer green sheet was about 200 μm.

Next, the firing process will be described. First, a heat treatment is performed to remove the binder present in the green sheet and the metal oxide paste. This binder removal processing is
It was carried out at 600 ° C. The organic binders of the green sheet and CuO paste used in this example are PVB and ethyl cellulose, which decompose in air at a temperature of 500 ° C. or higher.

In order to reduce the CuO paste, the binder-removed laminate was subjected to 2% atmosphere of 100% hydrogen gas.
The reduction treatment was performed at 00 ° C. for 5 hours. As a result of analyzing the CuO paste part of the obtained laminate by X-ray diffraction, it was found that Cu
It was confirmed that O was reduced to 100% Cu. After the reduction treatment, 90% in pure nitrogen using a mesh belt furnace.
The laminate was fired at 0 ° C.

The protruding electrode forming layer of the laminate produced as described above was removed by ultrasonic cleaning in the same manner as in Example 1. As a result, it was possible to form a protruding electrode made of a sintered body of the reduced metal oxide paste.

Example 4 In this example, a substrate forming paste and a bump electrode forming layer paste were used.
A substrate layer and a protruding electrode forming layer were formed on the surface of the sintered ceramic substrate.

MLS-1 manufactured by Nippon Electric Glass Co., Ltd. was used as the inorganic component of the substrate forming paste. To this inorganic component, polyvinyl butyral as an organic binder, di-n-butyl phthalate as a plasticizer, and a mixture of toluene and isopropyl alcohol as a solvent were mixed so as to have an appropriate viscosity to obtain a substrate forming paste. . In addition, alumina powder (Sumitomo Chemical Co., Ltd., ALM-41, average particle size 1.9 μm) was used as an inorganic component for the material of the paste for forming the bump electrode. Ethyl cellulose as an organic binder and a vehicle dissolved in terpineol were added to the above alumina powder and mixed by a three-stage roll so as to have an appropriate viscosity (30 Pa.s) to obtain a paste electrode forming layer paste.

The inorganic components of the CuO paste for wiring formation include CuO powder (average particle size 3 μm) and glass frit (LS-08, manufactured by Nippon Electric Glass Co., Ltd.) for increasing the adhesive strength.
03 glass powder, average particle diameter 2.5 μm) was added to CuO powder in an amount of 3 wt%. In the above inorganic component,
Ethyl cellulose, which is an organic binder, and a vehicle dissolved in terpineol were added and mixed so as to have an appropriate viscosity by a three-stage roll to obtain a CuO paste for wiring formation. The CuO paste for filling via holes was prepared by further adding 15% by weight of the glass-ceramic powder used in Example 1 to the CuO paste for forming wiring.

The substrate layer and the protruding electrode forming layer were formed on the surface of the sintered ceramic substrate by using the substrate forming paste and the protruding electrode forming layer paste. First, a substrate forming paste was applied to the surface of a sintered ceramic substrate to form a via hole and dried. The dried substrate forming paste layer was printed with a wiring pattern using a wiring forming paste and via hole filling using a via hole filling paste by a screen printing method.

Next, a paste electrode forming layer paste having a plurality of holes was printed on the substrate forming paste layer on which the wiring pattern formation and the via hole filling were completed. After drying the paste layer for the protruding electrode forming layer, the holes of the paste layer for the protruding electrode forming layer were filled with a CuO paste for filling via holes using a screen printing method. That is, the CuO paste for filling the via holes was used as the paste for forming the protruding electrodes.

Next, the firing process will be described. First, a substrate forming paste, a protruding electrode forming layer paste layer, and CuO
Heat treatment is performed to remove the binder present in the paste. This binder removal processing was performed at 600 ° C. The organic binder of the substrate forming paste, the bump electrode forming layer paste, and the CuO paste used in this example is PVB.
And ethyl cellulose, which are 5 in air
Decomposes above 00 ° C.

In order to reduce the CuO paste, the binder-removed laminate was subjected to 2% atmosphere of 100% hydrogen gas.
The reduction treatment was performed at 00 ° C. for 5 hours. As a result of analyzing the CuO paste part of the obtained laminate by X-ray diffraction, it was found that Cu
It was confirmed that O was reduced to 100% Cu. After the reduction treatment, 90% in pure nitrogen using a mesh belt furnace.
Baked at 0 ° C. A mixed gas of hydrogen gas and nitrogen gas may be used for the above reduction treatment.

The paste layer for the protruding electrode forming layer of the laminated body produced as described above was removed by ultrasonic cleaning in the same manner as in Example 1. As a result, it was possible to form a protruding electrode made of a sintered body of reduced metal oxide.

In this example, the substrate forming paste was used to form a substrate layer having a wiring pattern on the surface of the ceramic substrate and the substrate was fired. However, the substrate forming paste was printed on the substrate forming green sheet, and the substrate was formed. The firing of the forming paste layer and the firing of the substrate forming green sheet may be performed simultaneously.

Example 5 Using the green sheet for forming a protruding electrode having a thickness of 0.2 mm, a substrate having a protruding electrode was prepared by the manufacturing method of Example 1. FIG. 9 shows a view of the obtained ceramic substrate as seen from the back surface. Protruding electrode 1
6 are arranged in a grid pattern on the back surface of the ceramic substrate 15 at a pitch of 1.27 mm, and the height of the protruding electrodes is about 0.2.
It was constant in mm.

The ceramic substrate having the above-mentioned protruding electrodes was mounted on a printed circuit board (FR-4) by using solder so that the protruding electrodes of the ceramic substrate and the electrode pads on the printed circuit board were connected. First, the solder paste was printed on the electrode pad of the printed circuit board by the screen printing method. After arranging the ceramic substrate so that the protruding electrodes of the ceramic substrate were connected to the electrode pads on the printed circuit board, the solder was reflowed at 230 ° C. in a nitrogen atmosphere to be connected. FIG. 8 shows a sectional view of a structure in which the ceramic substrate 15 having the protruding electrodes 16 is mounted on the printed board 14. The electronic device 13 is mounted on the ceramic substrate in advance. The ceramic substrate 15 has a protruding electrode 16
It is mounted on the printed circuit board 14 by using the solder 12 via.

As described above, the ceramic substrate of the present invention was mounted on a printed board, and the frequency of occurrence of solder bridges at solder joints was evaluated. The solder bridge generated between adjacent electrodes was zero in 1000 points. That is,
When the ceramic substrate of the present invention is used, a solder bridge does not occur and highly reliable bonding can be obtained.

In the above example, Al ₂ O ₃ was used as the non-sintering material for the protruding electrode forming layer green sheet and the protruding electrode forming layer paste.
It was also possible to use eO, MgO, ZrO ₂ , TiO ₂ , BN or the like.

[0071]

As described above, the ceramic substrate of the present invention has the protruding electrode having a constant height, and the height can be increased so that the solder bridge is not generated.
The height of the bump electrode can be controlled by controlling the thickness of the green sheet for the bump electrode forming layer or the thickness of the coating film of the paste for the bump electrode forming layer. Further, by increasing the height of the protruding electrode, it is possible to suppress the destruction of the joint portion due to the thermal stress generated between the printed board and the ceramic board. In addition, since the height of the plurality of protruding electrodes of the ceramic substrate of the present invention is uniform, it is possible to prevent defective connection with the printed circuit board. Furthermore, according to the method for manufacturing a ceramic substrate of the present invention, the protruding electrode can be formed at the same time as the manufacturing of the ceramic substrate.
It is possible to inexpensively manufacture a ceramic substrate having a protruding electrode. The ceramic substrate having the protruding electrodes of the present invention can be used not only as a multi-chip substrate but also as a chip carrier.

[Brief description of drawings]

FIG. 1 is a perspective view of a back surface of a ceramic substrate after removing a protruding electrode forming layer according to an embodiment of the present invention.

FIG. 2 is a diagram showing steps of a method for manufacturing a ceramic substrate of Example 1;

FIG. 3 is a cross-sectional view of a laminated body used for manufacturing the ceramic substrate of Example 1.

FIG. 4 is a cross-sectional view of the laminated body obtained by firing the laminated body of FIG. 3 and removing alumina.

5 is a cross-sectional view of another laminated body used for manufacturing the ceramic substrate of Example 1. FIG.

FIG. 6 is a cross-sectional view of another laminated body used for manufacturing the ceramic substrate of Example 1.

FIG. 7 is a cross-sectional view of the laminated body after printing the alumina paste of Example 2.

FIG. 8 is a cross-sectional view of a ceramic substrate having protruding electrodes of Example 5 mounted on a printed circuit board.

FIG. 9 is a view of a ceramic substrate having protruding electrodes of Example 5 seen from the back surface.

[Explanation of symbols]

3 Green sheet for substrate formation 4 Green sheet for protruding electrode formation layer 5 wiring patterns 6 protruding electrodes

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yasuhiko Hakotani 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor, Minehiro Itagaki 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Incorporated (72) Inventor Kazuhiro Miura 1006, Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-6-53655 (JP, A) JP-A-59-75695 (JP, A) JP-A-54-104598 (JP, A) JP-A-2-25094 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H05K 3/40 H05K 3/34 501 H05K 3/46

Claims (21)

(57) [Claims] 1. A method of manufacturing a ceramic substrate having a plurality of protruding electrodes, comprising forming protruding electrodes on at least one surface of a green sheet laminate having an upper surface and a lower surface.
Forming the bump electrode having a plurality of holes using a layer paste
By printing a layer, filling the plurality of holes in the protruding electrode forming layer with the protruding electrode forming paste, firing the green sheet laminate, and removing the protruding electrode forming layer. , and a step of forming a protruding electrode of said plurality of the fired protrusion electrode forming paste
Method for manufacturing ceramic substrate . 2. A green sheet laminate before the firing step,
A step of heat-treating the green sheet laminate, the bump electrode forming paste and the bump electrode forming layer paste to remove organic substances contained in the bump electrode forming paste and the bump electrode forming layer paste; The method for manufacturing a ceramic substrate according to claim 1 , further comprising a step of reducing the electrode forming paste. 3. A step of forming a substrate forming paste layer by printing a substrate forming paste on at least one surface of the green sheet laminate before the step of providing the protruding electrode forming layer, Claim 1 including
Ceramic substrate manufacturing method. 4. The method for manufacturing a ceramic substrate according to claim 1 , wherein the paste for forming a protruding electrode layer contains an inorganic component that does not sinter at the firing temperature of the laminate firing step as a main component. 5. The paste for forming a protruding electrode is formed of Al ₂ O ₃ ,
The method for producing a ceramic substrate according to claim 1 , comprising at least one component selected from the group consisting of MgO, ZrO ₂ , TiO ₂ , BeO, and BN. 6. The bump electrode forming paste comprises Ag, Pd,
The ceramic according to claim 1, which is a conductor paste containing at least one component selected from the group consisting of Pt and Cu.
Substrate manufacturing method. 7. The method for manufacturing a ceramic substrate according to claim 1, wherein the bump electrode forming paste is a metal oxide paste containing CuO as a main component. 8. The method for manufacturing a ceramic substrate according to claim 1, wherein the plurality of protruding electrodes are columnar. 9. A method of manufacturing a ceramic substrate having a plurality of protruding electrodes, the method comprising providing a protruding electrode forming layer having a plurality of holes on at least one surface of a ceramic substrate having an upper surface and a lower surface, A step of filling the plurality of holes of the bump electrode forming layer with a paste for forming a bump electrode; a firing step of firing the ceramic substrate; and a step of firing the bump electrode forming layer by removing the bump electrode forming layer. Bei forming a protruding electrode of said plurality of the paste, the
A method for manufacturing the ceramic substrate . 10. The step of providing a protruding electrode forming layer comprises the step of forming a plurality of holes in at least one protruding electrode forming layer green sheet, and the at least one protruding electrode forming layer green sheet comprising a ceramic substrate. The step of providing on at least one surface of the ceramic according to claim 9.
Mic substrate manufacturing method. 11. Before the firing step, the protruding electrode forming layer green sheet and the protruding electrode forming paste are heat-treated in order to remove organic substances contained in the protruding electrode forming layer green sheet and the protruding electrode forming paste. The method of manufacturing a ceramic substrate according to claim 10 , further comprising: a step and a step of reducing the bump electrode forming paste. 12. The method for manufacturing a ceramic substrate according to claim 10 , wherein the green sheet for forming the protruding electrode layer contains an inorganic component that does not sinter at the firing temperature in the firing step as a main component. 13. The green sheet for forming a protruding electrode is A
l ₂ O ₃ , MgO, ZrO ₂ , TiO ₂ , BeO, and BN
Claim 10 comprising at least one component of the group consisting of
A method for manufacturing a ceramic substrate according to . 14. A step of providing a protruding electrode forming layer includes a step of printing the protruding electrode forming layer having a plurality of holes on at least one surface of a ceramic substrate using a protruding electrode forming layer paste. The ceramic according to claim 9.
Substrate manufacturing method. 15. Before the firing step, the protruding electrode forming paste and the protruding electrode forming layer paste are heat-treated in order to remove organic substances contained in the protruding electrode forming paste and the protruding electrode forming layer paste. The method further comprising a step and a step of reducing the bump electrode forming paste.
15. The method for manufacturing a ceramic substrate according to 14 . 16. The method further comprises the step of forming a substrate-forming paste layer by printing a substrate-forming paste on at least one surface of the ceramic substrate before the step of providing the protruding electrode forming layer. cell of claim 14
Method for manufacturing lamic substrate . 17. The method for producing a ceramic substrate according to claim 14 , wherein the paste for forming a protruding electrode layer contains an inorganic component that does not sinter at the firing temperature in the laminate firing step as a main component. 18. The paste for forming a protruding electrode is formed of Al.
_The method of manufacturing a ceramic substrate according to claim 14 , further comprising at least one component selected from the group consisting of ₂ O ₃ , MgO, ZrO ₂ , TiO ₂ , BeO, and BN. 19. The bump electrode forming paste is Ag, P
d, Serra of claim 14 Pt, and among the group consisting of Cu as a conductive paste containing at least one component
Mic substrate manufacturing method. 20. The method for manufacturing a ceramic substrate according to claim 9 , wherein the bump electrode forming paste is a metal oxide paste containing CuO as a main component. 21. The method for manufacturing a ceramic substrate according to claim 9 , wherein the plurality of protruding electrodes are columnar.