JP2000106306A - Ceramic substrate for electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a ceramic substrate for electronic components which can be cut into small substrates having very stable flat cut faces, even wen the substrate is cut along first cutting slits in a first stage. SOLUTION: First and second cutting slits 2 and 3 are formed into a ceramic substrate for electronic components in the longitudinal and transversal directions from the surface of the substrate, and the substrate is cut into strip-type divided substrates along the first slits 2. Then each strip-type divided substrate is cut into small substrate along the second slits 3. Each first slit 2 is formed, and its both end sections 21 are made deeper than its central part 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic substrate for an electronic component for extracting a chip-like electronic component such as a chip resistance component.

[0002]

2. Description of the Related Art Conventionally, a ceramic substrate for an electronic component (hereinafter, referred to as a large substrate) for extracting a plurality of chip-shaped electronic component elements has slits for dividing vertically and horizontally. A chip-shaped electronic component has been manufactured using the first splitting slit and the second splitting slit.

For example, when manufacturing a chip-shaped electronic component, a large-sized ceramic substrate having a plurality of first dividing slits and a plurality of second dividing slits formed vertically and horizontally is prepared.

Next, a region surrounded by the first divisional slit and the second divisional slit constitutes one electronic component element. First, surface regions are formed on both ends of each element region on the first divisional electrode side. Side terminal electrode is formed. At the same time, a back side terminal electrode is formed on the back side corresponding to the front side terminal electrode. Specifically, it is formed by baking using a conductive paste of Ag or an Ag alloy.

Next, in each element region, a resistor film is formed so as to straddle a pair of terminal electrodes on the front side. In particular,
It is formed by baking using a resistor paste such as ruthenium oxide.

Next, a glass protection is formed on at least the resistor film. Specifically, it is formed by printing and baking a low melting point glass paste. If necessary, the resistor film is laser-trimmed via a glass protective film to adjust the resistance value, and then the trimming mark is covered by printing and baking a glass paste.

Next, primary division is performed using the first division slit on the terminal electrode side of each element region. This allows
The large-sized ceramic substrate is a strip-shaped substrate having the first division slit portion as a division surface.

Next, the plurality of strip-shaped substrates are aligned so that the divided surfaces are the upper and lower surfaces, and the terminal electrodes are formed on the aligned divided surfaces by printing and printing an Ag-based paste. As a result, in one element region, the front surface side terminal electrode and the back surface side terminal electrode are connected by the end surface side terminal electrode.

Next, a terminal electrode, a resistor film and a glass protective film corresponding to each chip-like electronic component are formed from the strip-shaped substrate using the second dividing slit remaining on the strip-shaped substrate. Divide the substrate.

[0010] Finally, the surface of the end surface electrode of each small substrate is subjected to Ni plating, solder plating or the like by barrel plating or the like, thereby completing a chip resistor.

In the above-described large-sized ceramic substrate having the first dividing slit and the second dividing slit, for example, it is preferable that the groove depth of at least two dividing slits at both ends of the second dividing slit is increased. It has been proposed (JP-A-2-58884).

Also, only the first and second dividing slits, which are closer to the outer periphery than the substrate ends of the first and second dividing slits and the second dividing slit, are formed into other slits. It has been proposed to make it even deeper (JP-A-59-191220).

Further, only the first dividing slit and the second dividing slit, which are closer to the outer peripheral portion than the substrate ends of the first dividing slit and the second dividing slit formed in the vertical and horizontal directions, are connected to the center side. A large ceramic substrate has been proposed in which the slit is made deeper than the other slits and the other slit on the center side is not extended to the edge of the substrate.
-11,042).

The dividing slits of the ceramic substrate indicate the depth relationship of the dividing slits which are adjacent to each other and are orthogonal to each other, and are used to easily warp the substrate or perform the secondary dividing. Is merely disclosed.

A ceramic substrate having a splitting slit which is shallow near both ends of the splitting slit and deeper in other portions has also been proposed (Japanese Patent Laid-Open No. 61-13 / 1986).
No. 7390).

[0016]

However, the first dividing slits formed on the ceramic substrate and orthogonal to each other,
When the above-mentioned chip-shaped electronic component is manufactured using a ceramic substrate in which both of the second dividing slits have the same depth, and a ceramic substrate which is shallow near both ends of the dividing slit and deep in other portions. In particular, a large obstacle occurs in the first division. That is, the primary division is performed along the first division slit. However, in the strip-shaped substrate obtained by the primary division, the division is not stably performed near both ends of the division surface of the strip-shaped substrate, and the surface is not divided. Burrs and the like are generated.

Thus, for example, in order to form a terminal electrode on the end surface side, both end portions of the strip-shaped substrate are aligned using the alignment jig, and one of the divided end surfaces is used as a reference and the other divided end surface is formed on the other divided end surface. When performing printing or the like, the surface of the other divided end face of the plurality of strip-shaped substrates cannot be made uniform due to burrs generated at the end of the divided end face.

As a result, the amount of the conductive paste applied on the divided end face of the strip-shaped substrate varies, and a stable terminal electrode cannot be obtained.

In the worst case, conduction between the front terminal electrode and the rear terminal electrode cannot be achieved, and the terminal electrode is opened.

The present invention has been devised in view of the above-described problems, and has a very stable flatness even when the primary division processing is performed along the first division slit. To provide a ceramic substrate for an electronic component that can obtain the above.

[0021]

According to the present invention, a plurality of first dividing slits extending in one direction and a plurality of second dividing slits orthogonal to the first dividing groove are formed. A ceramic substrate for an electronic component which is divided along the first dividing slit into strip-shaped substrates and further divided along the second dividing slit to extract a substrate; The dividing slit is a ceramic substrate for electronic components, characterized in that both ends are formed deeper than the center.

[0022]

According to the present invention, the first dividing slit extending in one direction for performing the primary division has a groove depth at both end portions set deeper than a groove depth near the center. ing.

Therefore, even if the large ceramic substrate is divided into strip-shaped substrates, the state of the division surface is particularly stabilized. That is, generation of burrs can be suppressed.

Therefore, even if both end portions of a plurality of strip-shaped substrates are sandwiched or aligned by an alignment jig, even when the conductor film is applied to the end surfaces of the strip-shaped substrates or the like collectively, the uniformity can be obtained. Under such conditions, the conductor film can be formed.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a ceramic substrate for an electronic component according to the present invention will be described with reference to the drawings.

FIG. 1 is an external perspective view of a ceramic substrate for an electronic component according to the present invention, FIG. 2 is a cross-sectional view taken along a first dividing slit, and FIG. FIG. 4 is an external perspective view of a strip-shaped substrate obtained by performing primary division from a ceramic substrate. FIG. 4 is an external perspective view of a chip-shaped electronic component, for example, a chip resistor, formed from the ceramic substrate for electronic components.

In FIGS. 1 to 3, reference numeral 1 denotes a ceramic substrate (large ceramic substrate) for electronic components, 2... A first dividing slit extending in the X direction in the drawing, and 3.
Is a second dividing slit extending in the Y direction in the figure.
Reference numeral 4 denotes a strip-shaped substrate obtained by dividing the large ceramic substrate 1 along the first dividing slits 2.

In FIG. 4, reference numeral 5 denotes a substrate;
Reference numerals 1 and 42 denote terminal electrodes, in particular, 41a and 42a are front side terminal electrodes, 41b and 42b are end surface side terminal electrodes, 41
Reference numerals c and 42c denote back side terminal electrodes (shown by dotted lines on the back side of the substrate in FIG. 4), 43 denotes a resistor film, and 44 denotes a glass protective film (shown by dotted lines on the front side of the substrate in FIG. 4).

The large ceramic substrate 1 is made of an insulating ceramic such as alumina, and has a first horizontal dividing slit 2 and a second vertical dividing slit 3.
Are orthogonal to each other. An area surrounded by the first dividing slits 2... And the second dividing slits 3.

In the present invention, as shown in FIG. 2, the first dividing slits 2 have partially different groove depths. Specifically, the first dividing slit 2...
If the depth of the grooves 21 at both ends is D and the depth of the groove 22 at the center is d, the relation d <D is satisfied.

Further, both ends of the first splitting slit 2 refer to a region which substantially becomes the discarded ear portion B. In FIG. 2, of the second dividing slit grooves 3 intersecting with the first dividing slit 2, the region from both end portions to the second second dividing slit 32 is a discarded ear portion B. The depth D of the first splitting slit in that portion is deep.

The discarded ear portion B is a portion which is held and fixed by an alignment jig when aligning the strip-shaped substrates 4 described in the prior art. Therefore, in FIG. 2, the region from both end portions to the second second slit groove 32 up to the second portion is discarded as the ear portion B. However, depending on the shape of the alignment jig, the first second split portion from both ends is used. It may be a region up to the slit 31 for the first division or a region up to the third or more second division slits from both ends.

Further, in the second dividing slits 3, the depth of the groove of each second dividing slit 3 is made uniform, and the depth of the grooves of all the second dividing slits 3 is made equal. It is fundamental to make the uniformity.

However, this second dividing slit 3 is
It remains on the strip-shaped substrate 4 obtained by performing the primary division. When the substrate 5 corresponding to the element region A is secondarily divided from the strip substrate 4, it is necessary to consider the formation position and the depth of the second division slit so that the substrate 5 can be easily divided into two. .

For example, when dividing the strip-shaped substrate 4 into the substrates 5, for example, the strip-shaped substrate 4 is generally conveyed between a pair of pressing rollers and divided by the pressing force displaced from the upper and lower surfaces of the strip-shaped substrate 4. Is being done.

That is, there is a possibility that a sufficient moment cannot be obtained at the end of the strip-shaped substrate 4 on the last side of the division.

Therefore, the discarded ear portions B are formed at a sufficient interval on the end of the secondary divided final side, and the discarded ear portions B are formed.
The second dividing slits 3 that partition the element regions A only by the depth of the second dividing slit 3 located at the boundary between the element regions A, for example, the second dividing slit 32.
And the total width W of the discarded ear portions B is desirably wider than the width w of the element region A.

The depth D at both ends of the first dividing slit 2 is 5 times larger than the thickness T of the substrate 1.
It is 0% to 100%. That is, the depth D at both ends of the first division slit 2 may penetrate the entire thickness of the substrate 1.

Specifically, the thickness t of the substrate 1 is 0.4 m
m, and the depth D of both ends of the first dividing slit 2 is:
For example, it is 0.28 mm, and the depth d in the vicinity of the center is 0.3 mm.
15 mm.

The depth of the second dividing slit 3 is, for example, 0.06 mm, and all the second dividing groove slits 3 have the same depth.

The first slit 2 for the dividing groove of the substrate 1
If the depth D near both ends of the substrate is less than 50% with respect to the substrate t, burrs are formed on the divided surfaces near both ends when primary division is performed (burrs projecting 0.1 mm or more from the divided surface are generated) (A ratio of 0.2%) is likely to occur, and as a result, it is difficult to align a plurality of strip-shaped substrates 4 using both ends of the strip-shaped substrates 4 in a stable manner.

Preferably, the depth D near both ends of the first split groove slit 2 of the substrate 1 is 70% of the substrate t.
Above. By doing so, it is possible to further reduce the occurrence of burrs and the like by 0.1% on the divided surfaces near both ends when the primary division is performed.

The above-mentioned ceramic substrate 1 is formed by forming a ceramic green sheet made of alumina ceramic, and forming vertical and horizontal press molding on this sheet to form first and second dividing slit grooves 2 and 3. Then, it is formed by performing a firing treatment.

A method for manufacturing the chip-shaped electronic component shown in FIG. 4 from the above-described large ceramic substrate 1 will be described.

First, a large-sized ceramic substrate 1 having the first and second dividing slits 2 and a plurality of second dividing slits 3 formed as described above is prepared.

Next, on the surface of the region surrounded by the first splitting slit 2 and the second splitting slit 3, the front side terminal electrodes 41a are provided at both ends on the side of the first splitting groove slit 2. ,
42a is formed by baking an Ag-based conductive paste. At the same time, back side terminal electrodes 41c and 42c are formed on the back side corresponding to the front side terminal electrodes by baking an Ag-based conductive paste.

Next, in each element region, a resistor film 43 is formed by baking a resistor paste so as to straddle the pair of front side terminal electrodes 41a and 42a.

Next, a glass protective film 44 is formed on at least the resistor film 43. Specifically, it is formed by printing and baking a low melting point glass paste. If necessary, the resistor film 43 is laser-trimmed via the glass protective film 44 to adjust the resistance value, and then the trimming marks are covered by printing and printing glass paste. A plan view of the large ceramic substrate in this state is shown in a plan view of FIG. In the drawing, regions B at both ends in the direction in which the first dividing groove slit 2 extends are discarded ear portions, and a front-side terminal electrode, a rear-side terminal electrode, a resistor film and the like are formed in this region in principle. do not do.

Next, primary division is performed using the first division slit 2 of the large ceramic substrate 1. This allows
The large-sized ceramic substrate 1 becomes a strip-shaped substrate 4 having front-side terminal electrodes 41a and 42a, rear-side terminal electrodes 41c and 42c, and a resistive film 43 with the first dividing slit 2 as a dividing surface.

Next, the plurality of strip-shaped substrates 4 are sandwiched and aligned by the alignment jigs 61 and 62 at both ends thereof so that the divided surfaces of the plurality of strip-shaped substrates 4 become upper and lower surfaces.

At this time, burrs do not occur on the divided surfaces at both ends of the strip-shaped substrate 4, so that stable holding is possible. That is, when a plurality of strip-shaped substrates are aligned,
The surface can be a uniform surface with a plurality of strip-shaped substrates 4.

Next, a plurality of aligned strip-shaped substrates 4
On the surface (divided surface by the first division groove slit 2),
The end face side terminal electrodes 41b and 42c correspond to each element region.
Is formed by applying and baking an Ag-based paste.

As a result, the front-side terminal electrode 41a, the end-side terminal electrode 41b, the back-side terminal electrode 41c and the front-side terminal electrode 42a, the end-side terminal electrode 42b, and the back-side terminal electrode 42c are formed at both ends of each element region. Connected together,
A base conductor film for the terminal electrode is formed.

Next, by using the second dividing slit 3 remaining on the strip-like substrate 4, the base conductor film and the resistor film of the terminal electrodes 41, 42 corresponding to each chip-like electronic component from the strip-like substrate 4. Small substrate 4 formed with 43 and glass protective film 44
Is divided.

Finally, the surface of the terminal electrode base conductor film of each small substrate 4 is subjected to Ni plating, solder plating, or the like by barrel plating or the like. Thus, the terminal electrodes 41 and 42 are composed of the terminal electrode base conductor film and a plating layer such as Ni plating and solder plating. Then, the chip resistor shown in FIG. 4 is completed.

The depth D of the groove 21 at both ends of the first dividing slit 2 of the large-sized ceramic substrate is set to be deeper than the depth d of the groove 22 near the center of the slit 2. When the primary division is performed using the first division groove slit 2, the vicinity of both ends can be divided stably.

Thus, in the above-described step of arranging the plurality of strip-shaped substrates 4, it is very easy and stable to align the plurality of strip-shaped substrates 4 using the alignment jig using both ends of the strip-shaped substrates 4. (In a state where the surfaces of the substrate are aligned).

Therefore, for example, the end surface side terminal electrodes 41b and 42b in the chip resistor can be formed stably and reliably, and the front side terminal electrodes 41a and 42a and the back side terminal electrode 4
Poor connection between the first and second circuits 1c and 42c can be prevented.

In order to stably divide using the first dividing groove slit 2, it is conceivable to increase the groove depth of the first dividing groove slit 2 as a whole. However, in such a case, for example, the surface side terminal electrode 4
When forming 1a, 42a, back side terminal electrodes 41c, 42c, resistor film 43, and glass protective film 44, the substrate is divided by mechanical stress (for example, pressing force of a squeegee) generated during processing. As a result, the manufacturing process becomes complicated.

In the above-described embodiment, it is important to set the grooves 22 at both ends of the first split groove slit 2 deep. Therefore, in both end portions of the first split groove slit 2, a half-oval through groove may be formed whose planar shape passes through the entire width of the discarded ear portion B.

Further, it has been described that the portions where the grooves 22 at both end portions of the first split groove slit 2 are set deep correspond to the discarded ear portions B. For example, the second split slit 3 Of these, the region from the end of the substrate where the first divided groove is formed may be set deep. This is determined by the area where the handling of the alignment holding jig is set from the end of the substrate.

Although the manufacture of a chip resistor has been described as an example of the large ceramic substrate 1, it can be used for various chip components such as a multiple chip resistor and a CR chip component.

[0063]

As described above, in the ceramic substrate for an electronic component according to the present invention, the depth of the grooves at both ends is deep in the first division slit for performing the primary division of the ceramic substrate. (1) During the first division, the divided surfaces at both ends of the strip-shaped substrate can be divided with very stable flatness.

Therefore, when the strip substrates are aligned, they can be stably aligned, and the manufacturing process of various electronic components is very simple and stable.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a ceramic substrate for electronic components of the present invention.

FIG. 2 is a cross-sectional view of the ceramic substrate of FIG. 1 along a first dividing slit.

FIG. 3 is a perspective view of a strip-shaped substrate obtained from a ceramic substrate.

FIG. 4 is a perspective view of a chip resistor obtained from a ceramic substrate.

FIG. 5 is a partial plan view of a large ceramic substrate in a manufacturing process of the chip resistor.

FIG. 6 is a perspective view showing an alignment state of strip-shaped substrates in a manufacturing process of the chip resistor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Large ceramic substrate 2 ... Slit for 1st division groove 3 ... Slit for 2nd division groove 4 ... Strip-shaped substrate 5 ... Substrate

Claims (1)

[Claims] 1. A plurality of first dividing slits extending in one direction and a plurality of second dividing slits orthogonal to the first dividing grooves are formed, and are formed along the first dividing slit. In the ceramic substrate for electronic components, which is divided into strip-shaped substrates and further divided along the second dividing slit to extract the substrate, the plurality of first dividing slits have both ends in the center. A ceramic substrate for electronic components, characterized in that the slit depth is formed deeper than in the vicinity.