Ceramic motherboard and manufacturing method of electronic component

Abstract

To provide a ceramic motherboard that is easy to handle and can be easily broken along dividing grooves, and a manufacturing method of an electronic component.SOLUTION: There is provided a ceramic motherboard 100 that is integrated, via a dividing portion 20 having a dividing groove 21, with a plurality of ceramic substrates 10 on which electronic circuits are arranged. Therein the dividing portion 20 includes a brittle portion 22 that extends from a bottom 21b of the dividing groove 21 in a depth direction of the dividing groove 21 and has a strength less than that of the ceramic substrates 10.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a ceramic mother substrate and electronic components.

Background Art

[0002] As an example of a substrate used for electronic components such as light-emitting diodes, crystal oscillators, and MEMS (Micro Electro Mechanical Systems), a ceramic substrate can be mentioned. Such a ceramic substrate may be manufactured by dividing a ceramic mother substrate, which is a multi-substrate. As a ceramic mother substrate, one in which a plurality of ceramic substrates are adjacent via dividing grooves can be mentioned. In this case, when dividing the ceramic mother substrate into respective ceramic substrates, bending stress is applied to the ceramic mother substrate, and the ceramic mother substrate is cut along the dividing groove.

[0003] In Patent Document 1, dividing grooves are formed by performing press working or laser working on a ceramic green sheet serving as a ceramic mother substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When the dividing groove is too shallow, it may be difficult to cut along the dividing groove when cutting the ceramic mother substrate as described above. Therefore, it is conceivable to deepen the dividing groove. In this case, it is difficult to adjust the depth of the dividing groove. If the dividing groove is too deep, when handling the ceramic mother substrate, it may crack unnecessarily along the dividing groove, making handling difficult.

[0006] Therefore, an object of the present invention is to provide a ceramic mother substrate that is easy to handle and can be easily cut along a dividing groove, and a method for manufacturing an electronic component.

Means for Solving the Problems

[0007] In order to solve the above problems, the present invention provides a ceramic mother substrate in which a plurality of ceramic substrates on which electronic circuits are arranged are integrated via a dividing portion having a dividing groove, and the dividing portion extends from the bottom of the dividing groove in the depth direction of the dividing groove and includes a brittle portion having a lower strength than the ceramic substrate.

[0008] According to such a ceramic mother substrate, since the brittle portion extends from the bottom of the dividing groove, by applying stress to the ceramic mother substrate, it is easier to cut the ceramic mother substrate along the dividing groove compared to a ceramic mother substrate not having a brittle portion. Further, in this ceramic mother substrate, even if the dividing groove is not made deep, it is easy to cut along the dividing groove as described above. Therefore, it is possible to suppress the unnecessary cracking of the ceramic mother substrate along the dividing groove compared to the case where the dividing groove is provided to the same depth as the brittle portion without having a brittle portion. Therefore, this ceramic mother substrate is easy to handle.

[0009] Preferably, the dividing portion includes a non-brittle portion having a higher strength than the brittle portion on the side opposite to the dividing groove side with respect to the brittle portion.

[0010] By providing such a non-brittle portion in the dividing portion, it is possible to suppress the unnecessary cutting of the ceramic mother substrate compared to the case where the brittle portion extends to the surface on the side opposite to the side where the dividing groove of the ceramic mother substrate is provided and does not have a non-brittle portion. Therefore, the ceramic mother substrate can be made easier to handle.

[0011] Further, in the brittle portion, a part of the ceramic particles of the ceramic substrate on one side divided along the dividing groove and a part of the ceramic particles of the ceramic substrate on the other side are sintered together, and it is preferable that the porosity is higher than that of other than the brittle portion.

[0012] With the brittle part having such a configuration, it can be made common to the material of the brittle part and the material other than the brittle part. Therefore, compared with the case where the brittle part is made of a material different from the material other than the brittle part, the configuration of the ceramic mother substrate can be simplified.

[0013] Preferably, the width of the brittle part is smaller than the maximum width of the dividing groove.

[0014] In this case, compared with the case where the width of the brittle part is greater than or equal to the maximum width of the dividing groove, the generation of burrs derived from the brittle part remaining on the ceramic substrate after fragmentation can be reduced.

[0015] Preferably, the depth of the brittle part from the bottom is greater than the depth of the dividing groove.

[0016] Since the depth of the brittle part is greater than the depth of the dividing groove, the ceramic mother substrate can be easily cut without increasing the depth of the dividing groove.

[0017] Alternatively, preferably, the depth of the brittle part from the bottom is smaller than the depth of the dividing groove.

[0018] In this case, it is easy to suppress the unnecessary cracking of the ceramic mother substrate along the dividing groove.

[0019] Further, the present invention includes a cutting step of cutting a ceramic mother substrate in which a plurality of ceramic substrates on which electronic circuits are arranged are integrated via a dividing portion having a dividing groove along the dividing groove, and the dividing portion extends in the depth direction of the dividing groove from the bottom of the dividing groove and has a brittle part having a strength smaller than that of the ceramic substrate, and is a method for manufacturing an electronic component.

[0020] According to such a method for manufacturing an electronic component, as described above, the ceramic mother substrate can be easily cut along the dividing groove, and the unnecessary cracking of the ceramic mother substrate along the dividing groove can be suppressed. Therefore, compared with the case of using a ceramic mother substrate not provided with a brittle part, the electronic component can be easily manufactured.

Effect of the Invention

[0021] As described above, according to the present invention, there are provided a ceramic mother substrate that is easy to handle and easy to cut along the dividing groove, and a method for manufacturing an electronic component.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0023] Hereinafter, the ceramic mother substrate of the present invention and the method for manufacturing an electronic component will be described in detail with reference to the drawings. The embodiments illustrated below are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. The present invention can be changed and improved without departing from the spirit thereof within the scope of the claims. Note that, for ease of understanding, the scale of each drawing may be different from the scale described in the following description.

[0024] Figure 1 is a diagram showing an example of an electronic component manufactured according to the present embodiment. As shown in Figure 1, the electronic component 1 of the present embodiment is a crystal oscillator, and mainly includes a ceramic substrate 10, a conductive adhesive 51, a crystal blank 52, an insulating adhesive 53, and a lid 54. In the present embodiment, the conductive adhesive 51, the crystal blank 52, the insulating adhesive 53, and the lid 54 are components arranged on the ceramic substrate 10, and the conductive adhesive 51 and the crystal blank 52 are part of an electronic circuit.

[0025] The ceramic substrate 10 has a generally rectangular plate shape, and is provided with a pair of terminals 11 which are part of an electronic circuit on one surface side where components are arranged, and wirings 12 which are part of the electronic circuit connected to the respective terminals 11. At the corner of the ceramic substrate 10, a castellation 13 is formed. The castellation 13 in the present embodiment has a shape in which the rectangular corner is cut into a quarter circle, and side terminals 13a which are part of the electronic circuit are provided on the curved wall surface. On the surface of the ceramic substrate 10 where components are arranged, a quarter-circular ring-shaped electrode connected to the side terminals 13a is formed. The wiring 12 is connected to this quarter-circular ring-shaped electrode and is electrically connected to some of the side terminals 13a. Some of the other side terminals 13a are dummy terminals and the wiring 12 is not electrically connected. The metal films arranged on the surface of the ceramic substrate 10 such as the terminals 11, the wirings 12, and the side terminals 13a can be formed, for example, by applying a paste containing a conductive material (such as silver, copper, etc.) by screen printing and then drying and firing. Also, the metal film may be formed by vapor deposition, sputtering, plating, etc. The metal films may be laminated. For example, plating may be further applied on the metal film formed by applying a paste containing a conductive material by screen printing and then drying and firing.

[0026] The size of the ceramic substrate 10 is, for example, 3.2 mm (vertical width) × 2.5 mm (horizontal width) × 0.25 mm (thickness).

[0027] Note that examples of the ceramics constituting the ceramic substrate 10 include ceramics mainly composed of alumina, ceramics mainly composed of aluminum nitride, ceramics mainly composed of silicon nitride, ceramics mainly composed of mullite, and the like.

[0028] The conductive adhesive 51 is an adhesive having conductivity, and adheres the terminal 11 and the crystal blank 52 in a state where the crystal blank 52 is separated from the ceramic substrate 10.

[0029] The crystal blank 52 is a piezoelectric material cut at a determined shape, dimension, and angle with respect to the crystal axis of the crystal, and a pair of electrodes (not shown) are provided on the surface. The conductive adhesive 51 is adhered to these electrodes. The crystal blank 52 has a unique vibration mode and a unique frequency depending on its shape, dimension, and cutting angle.

[0030] The insulating adhesive 53 has a generally rectangular peripheral shape when the ceramic substrate 10 is viewed in plan, and is disposed on the ceramic substrate 10 so as to surround the crystal blank 52. The insulating adhesive 53 may be composed of an insulating double-sided tape containing an insulating aggregate. The insulating adhesive 53 adheres the ceramic substrate 10 and the lid 54.

[0031] The lid 54 is provided with a space (not shown) for accommodating the crystal blank 52 inside, and the side of the ceramic substrate 10 is open. The lid 54 is made of, for example, metal. By pressing the edge of the lid 54 against the insulating adhesive 53 and covering the crystal blank 52 with the lid 54, the crystal blank 52 is accommodated in the internal space, and the internal space is sealed.

[0032] The ceramic substrate 10 on which the electronic circuit is disposed and which constitutes a part of the electronic component 1 can be obtained through a cutting process of cutting a ceramic mother substrate, which is a multi-piece substrate in which a plurality of the ceramic substrates 10 are connected as individual substrates.

[0033] FIG. 2 is a plan view of the ceramic mother substrate. As shown in FIG. 2, the ceramic mother substrate 100 is provided with dividing portions 20 in a lattice pattern, and a plurality of ceramic substrates 10 are integrated via the dividing portions 20. Further, the outer peripheral portion 110 of the ceramic mother substrate 100 is a discard substrate that does not become a ceramic substrate 10. Further, the ceramic mother substrate 100 is provided with through holes 13H that become castellations 13. A metal film that becomes a side terminal 13a is provided on the inner peripheral surface of the through hole 13H. Further, terminals 11 and wirings 12 are provided on the surface of the ceramic mother substrate 100.

[0034] FIG. 3 is a cross-sectional view of the ceramic mother substrate 100 taken along line III-III in FIG. 2. As shown in FIG. 3, the dividing portion 20 includes a dividing groove 21, a brittle portion 22, and a non-brittle portion 23. Therefore, the dividing portion 20 visible in FIG. 2 is the dividing groove 21.

[0035] The dividing groove 21 of the present embodiment is generally formed as a V-groove. Therefore, the width of the dividing groove 21 is the smallest at the bottom 21b. The depth of the dividing groove 21 is preferably half or less of the thickness of the ceramic mother substrate 100 from the viewpoint of suppressing the unnecessary cracking of the ceramic mother substrate 100 along the dividing portion 20 when handling the ceramic mother substrate 100. Alternatively, from the viewpoint of facilitating the cutting of the ceramic mother substrate 100, the depth of the dividing groove 21 is preferably greater than half of the thickness of the ceramic mother substrate 100. Note that the dividing groove 21 is not limited to a V-groove, and may be, for example, a U-groove or a concave groove.

[0036] The brittle portion 22 is a portion having a lower strength than the ceramic substrate 10 and extends in the depth direction of the dividing groove 21 from the bottom 21b of the dividing groove 21. The brittle portion 22 preferably extends linearly in the depth direction. However, as long as the brittle portion 22 extends in the depth direction, it does not have to extend linearly, and may extend in a curved shape, a meandering shape, or a zigzag shape. The width of the brittle portion 22 is preferably smaller than the maximum width of the dividing portion 20 from the viewpoint of reducing the generation of burrs derived from the brittle portion 22 remaining on the ceramic substrate 10 after fragmentation.

[0037] It is preferable that the depth from the bottom 21b of the brittle portion 22 is greater than the depth of the dividing groove 21. In this case, even if the depth of the dividing groove 21 is not increased, the ceramic mother substrate 100 can be easily cut. Alternatively, the depth from the bottom 21b of the brittle portion 22 may be smaller than the depth of the dividing groove 21. In this case, it is easy to suppress the unnecessary cracking of the ceramic mother substrate 100 along the dividing groove 21.

[0038] FIG. 4 is an enlarged view of the brittle portion 22 and the non-brittle portion 23 surrounded by the dotted line in FIG. 3. In FIG. 4, the brittle portion 22 is indicated by a broken line. As shown in FIG. 4, the brittle portion 22 of the present embodiment has voids 22P larger than the voids in the portions other than the brittle portion 22, and in the brittle portion 22, the density of the ceramic particles 10C is smaller than that in other portions. That is, in the brittle portion 22, the porosity is higher than that in the portions other than the brittle portion 22. Further, in the brittle portion 22, a part of the ceramic particles 10C of the ceramic substrate 10 on one side divided along the dividing groove 21 and a part of the ceramic particles 10C of the ceramic substrate 10 on the other side are sintered together. In FIG. 4, the ceramic particles 10C1 of the ceramic substrate 10 on one side and the ceramic particles 10C2 of the ceramic substrate 10 on the other side are sintered. The sintered particles are bonded to each other and do not separate without applying stress. Therefore, the sintered particles are distinguished from the particles that are simply in contact with each other and can be separated without applying stress.

[0039] The non-brittle portion 23 is a portion having a higher strength than the brittle portion 22 and is located on the side opposite to the dividing groove 21 side with respect to the brittle portion 22. In the non-brittle portion 23, the ceramic particles 10C are densely sintered, and in the present embodiment, the density of the ceramic particles 10C is substantially the same as the density of the ceramic substrate 10 outside the dividing portion 20. For this reason, in the present embodiment, the strength of the non-brittle portion 23 is substantially equal to the strength of the ceramic substrate 10. The strength in this case refers to the strength per unit volume. Therefore, since the thickness of the non-brittle portion 23 along the depth direction of the dividing groove 21 is smaller than the thickness of the ceramic substrate 10, the non-brittle portion 23 is easier to cut than the ceramic substrate 10 outside the dividing portion 20.

[0040] Next, a method for manufacturing the electronic component 1 will be described.

[0041] FIG. 5 is a flowchart showing a method for manufacturing the electronic component 1 of the present embodiment. As shown in FIG. 5, this manufacturing method includes a preparation step P1, a split groove formation step P2, a crack formation step P3, a firing step P4, a pattern formation step P5, a cutting step P6, and a component arrangement step P7.

[0042] <Preparation step P1> This step is a step of preparing a ceramic green sheet for manufacturing the ceramic mother substrate 100. A ceramic green sheet is a raw sheet that becomes a ceramic sintered body by firing, and refers to the substrate before firing. FIG. 6 is a diagram showing the ceramic green sheet prepared in this step. As shown in FIG. 6, in this step, a flat ceramic green sheet 100G is prepared.

[0043] The ceramic green sheet 100G is manufactured as follows. For example, when the ceramic substrate 10 is made of alumina ceramics, a slurry is prepared by appropriately mixing alumina powder, a sintering aid, an organic binder, a solvent, a plasticizer, etc. Next, the prepared slurry is formed into a flat sheet shape by a doctor blade method, a calendar roll method, or the like. Finally, the formed sheet-shaped slurry is dried in a drying furnace or the like to evaporate the solvent, thereby obtaining a single-layer ceramic green sheet 100G. Note that the ceramic green sheet 100G may be produced by filling raw material powder into a molding machine and performing pressure molding, or may be produced by other methods.

[0044] <Split groove formation step P2> This step is a step of forming a groove that will become the split groove 21 of the ceramic mother substrate 100 in the ceramic green sheet 100G. FIG. 7 is a front view showing the ceramic green sheet 100G after this step, and FIG. 8 is a cross-sectional view taken along line VIII-VIII of the ceramic green sheet in FIG. 7.

[0045] In this embodiment, for example, a blade is pressed against the position that will become the dividing groove 21G of the ceramic green sheet 100G to form the dividing groove 21G. At this time, in order to form the through-hole 13HG that will become the through-hole 13H, the portion that will become the through-hole 13HG is punched out while pressing the blade. Note that the blade may be pressed multiple times to gradually push down the bottom 21Gb and gradually deepen the dividing groove 21G. In this case, the type of blade may be changed every predetermined number of times. For example, the thickness of the blade may be decreased every predetermined number of times. Alternatively, the ceramic green sheet 100G may be laser-processed to remove the portion that will become the dividing groove 21G, thereby forming the dividing groove 21G. At this time, in order to form the through-hole 13HG that will become the through-hole 13H, the portion of the ceramic green sheet 100G that will become the through-hole 13HG is removed by laser processing. When performing laser processing, it is preferable to collect the chips of the ceramic green sheet 100G generated by the laser processing using a dust collector. Examples of the laser include an excimer laser, a YAG laser, a carbon dioxide laser, and the like. Also, the dividing groove 21G and the through-hole 13HG may be formed by other methods. Further, the dividing groove 21G and the through-hole 13HG may be formed in separate processes. By forming the dividing groove 21G, the region 10G that will become the ceramic substrate 10 is formed.

[0046] <Crack formation step P3> This step is to form a crack that serves as the basis for the brittle part 22. Fig. 9 is a diagram showing the state of this step, and Fig. 10 is a diagram showing the ceramic green sheet 100G after this step in the same manner as Fig. 8. As shown in Fig. 9, the crack forming device 200 used in this step includes two belt conveyors 201, 202 and a roller 203 located between the belt conveyors 201, 202. The belt conveyors 201, 202 are arranged such that the respective conveying surfaces of the ceramic green sheet 100G are more than 180 degrees apart from each other. The belt conveyor 201 conveys the ceramic green sheet 100G to the roller 203, and the belt conveyor 202 conveys the ceramic green sheet 100G conveyed from the roller 203 to a stocker (not shown). At the roller 203, the ceramic green sheet 100G is bent so that the split groove 21G expands. Due to the bending stress at this time, a crack 22C occurs from the bottom 21Gb of the split groove 21G.

[0047] <Firing step P4> This step is to fire the ceramic green sheet 100G. In this step, the ceramic green sheet 100G is placed on a flat plate so that the ceramic particles separated by the crack 22C come into contact with each other. In this step, as described above, for example, when the ceramic substrate 10 is made of alumina ceramics, it is fired at a predetermined temperature (for example, a temperature of about 1400°C to 1800°C) at which alumina can sinter. By this firing, the ceramic green sheet 100G is sintered, and as shown in Fig. 4, a part of the ceramic particles separated by the crack 22C, that is, the ceramic particle 10C1 and the ceramic particle 10C2, are bonded by sintering. At this time, not all of the ceramic particles separated by the crack 22C are bonded. Therefore, voids 22P are formed by firing, and the brittle part 22 is formed. In this way, a plurality of ceramic substrates 10 are assembled as individual pieces to obtain a ceramic mother substrate 100 in a state where the terminals 11, the wirings 12, and the side terminals 13a are not arranged.

[0048] <Pattern forming step P5> This step is to provide terminals 11, wiring 12, and side terminals 13a on the ceramic mother substrate 100. In this step, for example, areas other than where the terminals 11, wiring 12, and side terminals 13a are to be provided are covered with a resist, and the terminals 11, wiring 12, and side terminals 13a are arranged by plating. Thus, a ceramic mother substrate 100 with the terminals 11, wiring 12, and side terminals 13a, which are part of the electronic circuit shown in FIG. 2, arranged thereon is obtained.

[0049] <Cutting step P6> This step is to cut the ceramic mother substrate 100 along the dividing groove 21. The cutting is performed by applying bending stress to the ceramic mother substrate 100 and cutting the ceramic mother substrate 100 along the dividing groove 21. At this time, it is preferable to use a substrate cutting tool. Thus, the ceramic substrate 10 shown in FIG. 1 is obtained.

[0050] <Component placement step P7> This step is to place components on the individualized ceramic substrate 10. In this embodiment, as shown in FIG. 1, a conductive adhesive 51 is placed on the terminal 11, and the crystal blank 52 is fixed while being separated from the ceramic substrate 10 by the conductive adhesive 51. Also, an insulating adhesive 53 is placed on the ceramic substrate 10 to fix the lid 54. Note that as long as the components are placed as a result, the components may be placed in an order different from the above description. Thus, a crystal oscillator as the electronic component 1 is obtained.

[0051] As described above, the ceramic mother substrate 100 of this embodiment is formed by integrating a plurality of ceramic substrates 10 on which electronic circuits are arranged via a dividing portion 20 having a dividing groove 21. The dividing portion 20 extends in the depth direction of the dividing groove 21 from the bottom of the dividing groove 21 and includes a brittle portion 22 having a lower strength than the ceramic substrate 10. Also, the manufacturing method of the electronic component of this embodiment includes a cutting step P6 of cutting the ceramic mother substrate 100 along the dividing groove 21.

[0052] In the ceramic mother substrate 100 of the present embodiment, since the brittle portion 22 extends from the bottom of the dividing groove 21, by applying stress to the ceramic mother substrate 100, compared with a ceramic mother substrate not provided with the brittle portion 22, the ceramic mother substrate 100 can be more easily cut along the dividing groove 21. Further, in this ceramic mother substrate 100, even if the dividing groove 21 is not made deeper, since it is easy to cut along the dividing groove 21, compared with the case where the dividing groove 21 is provided to the same depth as the brittle portion 22, it is possible to suppress the ceramic mother substrate 100 from being unnecessarily cut along the dividing groove 21. Therefore, the ceramic mother substrate 100 of the present embodiment is easy to handle. Therefore, according to the method for manufacturing an electronic component of the present embodiment, compared with the case of using a ceramic mother substrate not provided with the brittle portion 22, an electronic component can be more easily manufactured.

[0053] Further, in the ceramic mother substrate 100 of the present embodiment, the dividing portion 20 includes a non-brittle portion 23 having a higher strength than the brittle portion 22 on the side opposite to the dividing groove 21 side with respect to the brittle portion 22. By the dividing portion 20 including such a non-brittle portion 23, compared with the case where the brittle portion 22 extends to the surface on the side opposite to the side where the dividing groove 21 of the ceramic mother substrate 100 is provided, it is possible to suppress the ceramic mother substrate 100 from being unnecessarily cut.

[0054] Further, in the brittle portion 22 of the present embodiment, a part of the ceramic particles 10C1 of the ceramic particles 10C on one side of the ceramic substrate 10 divided along the dividing groove 21 and a part of the ceramic particles 10C2 of the ceramic particles 10C on the other side of the ceramic substrate 10 are sintered to each other, and the porosity is higher than that outside the brittle portion 22. Since the brittle portion 22 has such a configuration, the material of the brittle portion 22 can be made common with the material other than the brittle portion 22. Therefore, compared with the case where the brittle portion 22 is formed of a material different from the material other than the brittle portion 22, the configuration of the ceramic mother substrate 100 can be simplified.

[0055] As described above, the present invention has been described by taking the above embodiment as an example, but the present invention is not limited to the above example.

[0056] For example, in the above embodiment, a crystal oscillator was described as an example of the electronic component. However, the electronic component according to the present invention is not limited to a crystal oscillator, and may be, for example, a MEMS, an LED (Light Emitting Diode) optical element, a chip resistor, or the like. In the case of a MEMS, for example, an electronic circuit that becomes a gyro sensor, an acceleration sensor, a pressure sensor, or the like, and wiring is disposed on a ceramic substrate. In the case of an LED optical element, for example, an electronic circuit composed of an LED element and wiring or the like is disposed on a ceramic substrate. Further, in the case of a chip resistor, for example, a resistor body made of silver and palladium, or ruthenium oxide, and an electronic circuit composed of wiring or the like are disposed on a ceramic substrate. Also, the castellations 13 are not essential. Therefore, the through holes 13H may not be formed in the ceramic mother substrate 100.

[0057] Further, in the above embodiment, the non-brittle portion 23 having a strength greater than that of the brittle portion 22 is provided on the side opposite to the split groove 21 side with respect to the brittle portion 22. However, for example, the brittle portion 22 may extend to the surface on the side opposite to the split groove 21 side of the ceramic mother substrate 100, and the non-brittle portion 23 may not be provided.

[0058] Further, the configuration of the brittle portion 22 may be different from that of the above embodiment. For example, in the brittle portion 22, the density of the ceramic particles 10C may be the same as that outside the brittle portion 22, and the ceramic particles 10C in the brittle portion 22 may be made of a material having a smaller bonding force than the ceramic particles outside the brittle portion 22. In this case, for example, when forming the ceramic green sheet 100G, a material having a strength smaller than that of other portions after sintering is added to the position where the brittle portion 22 is to be formed.

[0059] Further, the width of the brittle portion 22 may be equal to or greater than the maximum width of the split groove 21.

[0060] Also, the manufacturing method of the electronic component 1 may be different from the above-described embodiment as long as it includes the cutting step P6. For example, the preparation step P1 and the split groove formation step P2 may be performed simultaneously. Also, the split groove formation step P2 and the crack formation step P3 may be performed simultaneously. In this case, for example, the thickness of the blade for forming the split groove 21G may be increased, and the blade may be pressed against the ceramic green sheet 100G so that the crack 22C is formed. Also, the crack formation step P3 may be performed by a method different from the above-described embodiment. Also, a component placement step P7 may be provided after the pattern formation step P5 and before the cutting step P6. For example, after providing the terminals 11, the wiring 12, and the side terminals 13a on the ceramic mother substrate 100, a resistor made of silver and palladium, or ruthenium oxide or the like is formed, and the ceramic mother substrate 100 is cut to obtain a chip resistor as the electronic component 1.

[0061] Also, when the ceramic mother substrate 100 is cut in the cutting step P6, a part of the electronic circuit such as the terminals 11, the wiring 12, and the side terminals 13a may not be arranged on the ceramic mother substrate 100. In this case, the pattern formation step is performed after the ceramic substrate 10 is separated into individual pieces, and the components are arranged.

Industrial Applicability

[0062] As described above, according to the present invention, there are provided a ceramic mother substrate that is easy to handle and easy to cut along the split groove, and a method for manufacturing an electronic component, which can be used in the field of electronic component manufacturing and the like.

Explanation of Signs

[0063] 1 ··· Electronic component 10 ··· Ceramic substrate 11 ··· Terminal 12 ··· Wiring 13 ··· Castellation 20 ··· Split part 21, 21G ··· Split groove 22 ··· Brittle part 22C ··· Crack 23 ··· Non-brittle part 100 ··· Ceramic mother substrate 100G ··· Ceramic green sheet P1 ··· Preparation process P2 ··· Division groove formation process P3 ··· Crack formation process P4 ··· Firing process P5 ··· Pattern formation process P6 ··· Cutting-off process P7 ··· Component placement process

Claims

1. A ceramic mother substrate in which a plurality of ceramic substrates on which electronic circuits are arranged are integrated via a dividing portion having a dividing groove, wherein the dividing portion extends in the depth direction of the dividing groove from the bottom of the dividing groove and includes a brittle portion having a lower strength than the ceramic substrate. A ceramic mother substrate characterized by the above.

2. The dividing portion includes a non-brittle portion having a higher strength than the brittle portion on the side opposite to the dividing groove side with respect to the brittle portion. The ceramic mother substrate according to claim 1, characterized by the above.

3. In the brittle portion, a part of the ceramic particles of the ceramic substrate on one side divided along the dividing groove and a part of the ceramic particles of the ceramic substrate on the other side are sintered together, and the porosity is higher than that outside the brittle portion. The ceramic mother substrate according to claim 1 or 2, characterized by the above.

4. The width of the brittle portion is smaller than the maximum width of the dividing groove. The ceramic mother substrate according to claim 1 or 2, characterized by the above.

5. The depth of the brittle portion from the bottom is greater than the depth of the dividing groove. The ceramic mother substrate according to claim 1 or 2, characterized by the above.

6. The depth of the brittle portion from the bottom is smaller than the depth of the dividing groove. The ceramic mother substrate according to claim 1 or 2, characterized by the above.

7. A cutting step of cutting a ceramic mother substrate in which a plurality of ceramic substrates on which electronic circuits are arranged are integrated via a dividing portion having a dividing groove along the dividing groove, wherein the dividing portion extends in the depth direction of the dividing groove from the bottom of the dividing groove and has a brittle portion having a lower strength than the ceramic substrate. A method for manufacturing an electronic component, characterized by the above.

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