JP2002353363A - Ceramic wiring board for taking many pieces - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and precisely divide a ceramic base substrate along dividing grooves. SOLUTION: On a substantially square tabular base plate part 2a having a mounting part 2c where electronic components are mounted on upper side in the central part, a number of wiring substrate regions 2 are formed by stacking a substantially square frame-shaped frame part 2b surrounding the mounting part 2c where a step 2e protruding inside a pair of sides facing each other of the inner peripheral surface. On the upper side of ceramic base substrate 1 which is arrayed and formed in lengthwise and breadthwise lines, dividing grooves 3a, 3b dividing each wiring substrate region 2 are formed in the direction being parallel to the face of the side having the step 2e and in the direction being perpendicular to this. Depth of the dividing groove 3a in the direction being parallel to the face of the side having the step 2e is slighter than that of the dividing groove 3b being perpendicular to this.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized ceramic mother board having a large number of wiring board regions, which are to be mounted on a large-sized ceramic mother board, in a horizontal and vertical direction. The present invention relates to a multi-cavity ceramic wiring board formed in an arrayed manner.

[0002]

2. Description of the Related Art Conventionally, a small-sized wiring board used for an electronic component housing package for housing electronic components such as a semiconductor element and a crystal oscillator is made of a ceramic material such as an aluminum oxide sintered body. A substantially rectangular flat bottom plate having a mounting portion for mounting electronic components at the center of the upper surface, and a bottom plate that is stacked on the upper surface of the bottom plate so as to surround the mounting portion. And a substantially rectangular frame-shaped frame having a stepped portion projecting inward on a pair of opposing surfaces of the inner peripheral surface of the frame, and from the top of the stepped portion of the frame. A plurality of metallized wiring conductors are formed penetrating the frame over the outer peripheral side surface of the frame and the lower surface of the bottom plate. Then, the electronic component is mounted and fixed on the mounting portion of the bottom plate, and the electrodes of the electronic component are electrically connected to the metallized wiring conductors on the upper surface of the step portion of the frame via bonding wires. An electronic device as a product is obtained by joining a lid made of metal, glass, or the like so as to seal the electronic component, and hermetically housing the electronic component in a container including the wiring board and the lid.

[0003] In recent years, with the recent demand for miniaturization of electronic devices, the size of such a wiring board has become extremely small, on the order of several mm square, and a large number of wiring boards must be handled. In order to facilitate the manufacture of wiring boards and electronic devices, a large number of wiring boards are simultaneously and intensively obtained from a single large-area ceramic mother board. It is manufactured in the form of a ceramic array substrate.

[0004] This multi-cavity ceramic wiring board is formed by forming a large number of wiring board regions, each of which becomes the above-mentioned wiring board, vertically and horizontally and integrally in a large-area ceramic mother board. In each of the wiring board regions, a substantially square frame-shaped frame portion serving as the above-described frame is laminated on a substantially square flat plate-shaped bottom plate portion serving as the above-described bottom plate. The above-described mounting portion is formed at the center of the upper surface of the bottom plate portion, and the above-described step portion is formed at a pair of inner circumferences of the frame body portion facing each other. The above-mentioned metallized wiring conductor is formed from the upper surface of the step portion to the lower surface of the bottom plate. Further, on the upper surface of the ceramic mother substrate, division grooves having a predetermined depth are formed vertically and horizontally to divide each wiring substrate region, and a large number of small wirings are formed by bending the ceramic mother substrate along the division grooves. Substrates can be obtained simultaneously and intensively.

The multi-cavity ceramic wiring board is manufactured by a ceramic green sheet laminating method. Specifically, first, one or more ceramic green sheets for the bottom plate portion in which a large number of substantially rectangular flat plate-shaped regions serving as the above-described bottom plate portion are vertically and horizontally arranged integrally and the above-mentioned frame body portion In addition to preparing two or more ceramic green sheets for a frame part in which a large number of substantially rectangular frame-shaped regions are vertically and horizontally arranged and integrally formed, the above-mentioned metallized wiring is provided on these ceramic green sheets. After printing and applying a metallizing paste to be a conductor, these ceramic green sheets are stacked up and down to obtain a ceramic green sheet laminate that becomes a ceramic mother substrate in which the regions to be each wiring board region are arranged vertically and horizontally, and Next, an area to be each wiring board area is separated on the upper surface of the ceramic green sheet laminate by, for example, a cutter blade or a mold. Cut to form for splitting groove, and finally manufactured by sintering the ceramic green sheet laminate at a high temperature.

[0006]

However, according to the conventional multi-cavity ceramic wiring board, the stepped portion is formed by the stress generated when the cut for the dividing groove is formed in the ceramic green sheet laminate for the ceramic mother board. A part of the cut formed in the direction orthogonal to the surface having the pattern is likely to be closed, and therefore, the divided grooves formed in the ceramic mother substrate obtained by firing the ceramic green sheet laminate may adhere. Yes, if there is such adhesion, it is difficult to divide the ceramic mother board along the dividing groove, and it is difficult to divide the obtained wiring board easily due to burrs and cracks. Had problems.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multi-cavity ceramic wiring board which can easily and accurately divide a ceramic mother board along a dividing groove without causing the dividing grooves formed in the ceramic mother board to adhere. Is to provide.

[0008]

SUMMARY OF THE INVENTION A multi-piece ceramic wiring board according to the present invention surrounds a mounting portion on a substantially square flat plate-like bottom plate having a mounting portion in the center of an upper surface on which electronic components are mounted. A ceramic mother board in which a large number of wiring board regions are vertically and horizontally arranged and formed by laminating a substantially rectangular frame-shaped frame portion in which a step portion projecting inward is formed on a pair of opposing inner peripheral surfaces. A multi-cavity ceramic wiring board formed on a top surface thereof with a dividing groove for dividing each wiring board region formed in a direction parallel to the surface having the stepped portion and in a direction orthogonal to the surface having the stepped portion. Is characterized in that the depth of the dividing groove in the direction parallel to the surface is smaller than the depth of the dividing groove orthogonal to this.

According to the multi-cavity ceramic wiring board of the present invention, since the depth of the dividing groove in the direction parallel to the surface having the step portion is smaller than the depth of the dividing groove orthogonal to the surface, the ceramic mother board is formed. When making cuts for the dividing grooves in the ceramic green sheet laminate to be the substrate, the rigidity is high and it is difficult to deform by the amount of the steps on the side of the frame that has the steps, so even if the cuts for the dividing grooves are shallow. This notch is difficult to close, and on the side orthogonal to this, the effect of the stress generated when forming the notch on this step side is small because the notch on the step side is shallow, so a part of the notch for the dividing groove is It is hard to close.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a multi-cavity ceramic wiring board according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a perspective view showing an embodiment of a multi-cavity ceramic wiring board according to the present invention, wherein 1 is a ceramic mother board, 2 is a wiring board region, and 3a and 3b are division grooves.

The ceramic mother substrate 1 is composed of, for example, three insulating layers 4 and 5 made of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, and a glass-ceramic. A large number of wiring board regions 2 each of which becomes a small-sized wiring board are vertically and horizontally arranged in an integrated manner in a central portion thereof.

As shown in a partially enlarged sectional view of FIG. 2, each of the wiring board regions 2 arranged and formed in the center of the ceramic mother board 1 has a substantially square flat bottom plate portion 2 formed of an insulating layer 4.
a and a substantially rectangular frame portion 2b formed of ceramic layers 5 and 6. The bottom plate portion 2a has a mounting portion 2c for mounting an electronic component at the center of the upper surface thereof, and the electronic component is bonded and fixed to the mounting portion 2c via an adhesive such as brazing material, glass or resin. . On the other hand, the frame 2
b is laminated on the bottom plate portion 2a so as to surround the mounting portion 2c of the bottom plate portion 2a. The top surface has a sealing surface 2d having substantially the same width on each side and an inner peripheral surface thereof. The ceramic layer 5 has a stepped portion 2e formed so as to protrude inward on a pair of opposed surfaces. As a result, the side of the frame body 2b having the stepped portion 2e is wider than the side of the other side.

Further, each frame portion 2b extends from the upper surface of the step portion 2e.
A metallized wiring conductor 7 made of metallized metal powder such as tungsten, molybdenum, copper, silver or the like is formed on the lower surface of the bottom plate 2a via the outer peripheral side surface of the bottom plate 2a. Electrodes of the electronic component are electrically connected to the portion 2e via electrical connection means such as a bonding wire.

The insulating layers 4, 5, 6 and the metallized wiring conductors 7 in the ceramic mother substrate 1 are made of aluminum oxide, if the insulating layers 4, 5, 6 are made of an aluminum oxide sintered body. An appropriate organic binder and a solvent are added to raw material powders such as silicon oxide, calcium oxide, and magnesium oxide to form a slurry, which is then formed into a sheet by using a conventionally known doctor blade method. A ceramic green sheet for the insulating layers 4, 5, and 6 is prepared by punching using a punching die, and a tungsten paste for the metallized wiring conductor 7 is formed on the ceramic green sheet by a screen printing method in a predetermined pattern. And then apply these ceramic green sheets on top and bottom Is formed by firing at a temperature of the ceramic green sheet laminate approximately 1600 ° C. in a reducing atmosphere with form a ceramic green sheet laminate Te.

Further, on the upper surface of the ceramic mother substrate 1,
The dividing grooves 3a and 3b for dividing each wiring board region 2
The b is formed in a direction parallel to the surface having the step portion 2e and a direction perpendicular thereto. Dividing grooves 3a and 3b
Has a substantially V-shaped cross-section and varies depending on the thickness, material, and the like of the ceramic mother substrate 1, but has a depth of 0.05 to 1.
The opening width is about 5 mm and the opening width is about 0.01 to 0.3 mm. Such dividing grooves 3a and 3b are formed by pressing a cutter blade, a mold, or the like on the upper surface of the ceramic green sheet laminate for the ceramic mother substrate 1 to make cuts.

After the electronic components are mounted on the mounting portion 2c of each wiring board region 2, the ceramic mother substrate 1 is divided along the dividing grooves 3a and 3b, so that a large number of electronic devices can be simultaneously and intensively integrated. It is manufactured.

In the present invention, the depth of the dividing groove 3a formed in a direction parallel to the surface having the stepped portion 2e on the inner peripheral surface of the frame 2b is formed in a direction perpendicular to this. It is shallower than the depth of the divided groove 3b, which is important.

As described above, the dividing groove 3 formed in the direction parallel to the surface having the step 2e on the inner peripheral surface of the frame 2b.
a divided groove 3b formed in a direction in which the depth of “a” is orthogonal to the depth
Is smaller than the depth of the ceramic green sheet laminate for the ceramic mother substrate 1.
When the cuts for a and 3b are made, these cuts are difficult to close, and therefore, adhesion to the divided grooves 3a and 3b hardly occurs. This is because, in a region to be the frame portion 2b of the ceramic green sheet laminate for the ceramic mother substrate 1, the side having the step portion has high rigidity and is not easily deformed by the step portion, so that the cut for the dividing groove 3a is shallow. However, the notch is difficult to close, and on the side orthogonal to the notch, the effect of the stress generated when the notch for the dividing groove 3a is formed by the shallow amount of the notch for the dividing groove 3a is small, so that the notch for the dividing groove 3b is small. This is because the cut is difficult to close.

The depth of the dividing groove 3a formed in a direction parallel to the surface of the inner peripheral surface of the frame 2b having the stepped portion 2e is parallel to the depth of the dividing groove 3b formed in a direction perpendicular to the surface. If the depth is less than 0.05 mm less than the depth, adhesion is likely to occur in the divided groove 3b formed in a direction perpendicular to the surface having the step portion 2e, and if the depth is more than 0.5 mm, It becomes difficult to divide the ceramic mother substrate 1 along the dividing grooves 3a. Therefore, the depth of the dividing groove 3a formed in a direction parallel to the surface having the stepped portion 2e on the inner peripheral surface of the frame body 2b is larger than the depth of the dividing groove 3b formed in a direction orthogonal to this. Is also preferably 0.05 to 0.5 mm shallower.

Thus, according to the multi-cavity ceramic wiring board of the present invention, after the electronic component is mounted on the mounting portion 2c of each wiring board area 2, the ceramic mother board 1 is divided into the dividing grooves 3
By dividing the device along a 3b, an electronic device free from burrs and cracks can be provided.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention. For example, in the above-described embodiment, the ceramic mother substrate 1 has three insulating layers 4.5.
The ceramic motherboard 1 may be manufactured by stacking four or more insulating layers.

[0023]

As described above, according to the multi-cavity ceramic wiring board of the present invention, the depth of the dividing groove in the direction parallel to the surface having the step on the inner peripheral surface of the frame body is reduced. Since the grooves are shallower than the depth of the dividing grooves orthogonal to the above, when the cuttings for the dividing grooves are made in the ceramic green sheet laminate serving as the ceramic mother substrate, some of these cuts are not easily closed. Therefore, it is possible to provide a multi-cavity ceramic wiring board that can easily and accurately divide the ceramic mother substrate along the division grooves without adhesion in the division grooves.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a multi-cavity ceramic wiring board according to the present invention.

FIG. 2 is a partially enlarged sectional view of the multi-cavity ceramic wiring board shown in FIG. 1;

[Explanation of symbols]

 1 Ceramic mother board 2 Wiring board area 2a Bottom plate 2b Frame 2c Mounting part 2e .Steps 3a, 3b: Dividing groove

Claims (1)

[Claims] 1. A substantially rectangular flat bottom plate having a mounting portion on which an electronic component is mounted at the center of the upper surface, surrounding the mounting portion, and projecting inward from a pair of opposing inner peripheral surfaces thereof. On the upper surface of a ceramic mother substrate in which a large number of wiring board regions formed by laminating substantially square frame-shaped frame portions on which step portions are formed are formed on the upper surface of a ceramic mother substrate arranged in a matrix, a dividing groove for separating each of the wiring board regions is provided. A multi-cavity ceramic wiring board formed in a direction parallel to the surface having the step portion and in a direction perpendicular to the surface, the depth of the dividing groove in a direction parallel to the surface having the step portion. A multi-cavity ceramic wiring board, characterized in that the depth is smaller than the depth of a dividing groove orthogonal to this.