Ceramic motherboard and method for manufacturing electronic component

Abstract

Provided is a ceramic motherboard (100) having a plurality of ceramic substrates (10) which are integrated via dividing sections (20) having dividing grooves (21) and on which electronic circuits are disposed, wherein each dividing section (20) is provided with a brittle section (22) that extends from a bottom section (21b) of the dividing groove (21) in the depth direction of the dividing groove (21) and that has less strength than the ceramic substrates (10).

Description

Ceramic motherboard and method for manufacturing electronic components

[0001] The present invention relates to a ceramic motherboard and a method for manufacturing an electronic component.

[0002] Ceramic substrates are an example of substrates used in electronic components such as light-emitting diodes, quartz crystal oscillators, and MEMS (Micro Electro Mechanical Systems). Such ceramic substrates are sometimes manufactured by dividing a multi-piece ceramic mother substrate. Examples of ceramic mother substrates include those in which multiple ceramic substrates are adjacent to each other via dividing grooves. In this case, when dividing the ceramic mother substrate into individual ceramic substrates, bending stress is applied to the ceramic mother substrate, and the ceramic mother substrate is broken along the dividing grooves.

[0003] In Patent Document 1, dividing grooves are formed by pressing or laser processing a ceramic green sheet that serves as a ceramic mother substrate.

[0004] Japanese Patent Application Laid-Open No. 2020-043179

[0005] If the dividing grooves are too shallow, it may be difficult to split the ceramic mother substrate along the dividing grooves as described above. Therefore, it is possible to make the dividing grooves deeper. In this case, it is difficult to adjust the depth of the dividing grooves. If the dividing grooves are too deep, the ceramic mother substrate may unnecessarily split along the dividing grooves when handled, making it difficult to handle.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a ceramic motherboard that is easy to handle and can be easily split along the dividing grooves, and a method for manufacturing an electronic component.

[0007] In order to solve the above problems, the present invention provides a ceramic mother board in which multiple ceramic substrates on which electronic circuits are arranged are integrated via a dividing section having a dividing groove, wherein the dividing section extends from the bottom of the dividing groove in the depth direction of the dividing groove and is characterized by having a brittle section having less strength than the ceramic substrates.

[0008] In such a ceramic mother substrate, brittle portions extend from the bottoms of the dividing grooves, so that applying stress to the ceramic mother substrate makes it easier to fracture the ceramic mother substrate along the dividing grooves than a ceramic mother substrate without brittle portions. Furthermore, because this ceramic mother substrate can be easily fractured along the dividing grooves as described above without deep dividing grooves, it is possible to prevent the ceramic mother substrate from undesirably cracking along the dividing grooves compared to a ceramic mother substrate without brittle portions and with dividing grooves extending to the same depth as the brittle portions. Therefore, this ceramic mother substrate is easy to handle.

[0009] The dividing portion preferably includes a non-brittle portion having greater strength than the brittle portion on the side opposite to the dividing groove side of the brittle portion.

[0010] The division section having such a non-brittle portion can prevent the ceramic mother substrate from being unnecessarily broken, compared to a case where the brittle portion extends to the surface of the ceramic mother substrate opposite the side where the division groove is provided and no non-brittle portion is provided, thereby making the ceramic mother substrate easier to handle.

[0011] Furthermore, in the brittle portion, it is preferable that some of the ceramic particles of the ceramic substrate on one side divided along the dividing groove and some of the ceramic particles of the ceramic substrate on the other side are sintered to each other, and that the porosity is higher than in areas other than the brittle portion.

[0012] By configuring the brittle portion in this manner, the brittle portion can be made of the same material as the other portions, which simplifies the configuration of the ceramic mother substrate compared to when the brittle portion is made of a different material from the other portions.

[0013] The width of the brittle portion is preferably smaller than the maximum width of the dividing groove.

[0014] In this case, compared to when the width of the brittle portion is equal to or greater than the maximum width of the dividing groove, the occurrence of burrs resulting from the brittle portion remaining on the ceramic substrate after singulation can be reduced.

[0015] The depth of the brittle portion from the bottom is preferably greater than the depth of the dividing groove.

[0016] By making the depth of the brittle portion greater than the depth of the dividing groove, the ceramic base substrate can be easily fractured without increasing the depth of the dividing groove.

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

[0018] In this case, it is possible to easily prevent the ceramic mother substrate from unnecessarily cracking along the dividing grooves.

[0019] The present invention also provides a method for manufacturing an electronic component, comprising a splitting step of splitting a ceramic mother substrate, in which a plurality of ceramic substrates on which electronic circuits are arranged are integrated via a splitting portion having a split groove, along the split groove, wherein the splitting portion extends from the bottom of the split groove in the depth direction of the split groove and has a brittle portion having a strength less than that of the ceramic substrates.

[0020] According to this method for manufacturing electronic components, the ceramic mother substrate can be easily split along the dividing grooves, and unwanted cracking of the ceramic mother substrate along the dividing grooves can be prevented, which makes it easier to manufacture electronic components than when using a ceramic mother substrate that does not have a brittle portion.

[0021] As described above, the present invention provides a ceramic motherboard that is easy to handle and can be easily split along the dividing grooves, and a method for manufacturing an electronic component.

[0022] FIG. 1 is a diagram showing an example of an electronic component manufactured by the present invention. FIG. 2 is a diagram showing a ceramic mother substrate according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of the ceramic mother substrate taken along line III-III. FIG. 4 is an enlarged view of the brittle portion and non-brittle portion enclosed by the dotted line in FIG. 3. FIG. 5 is a flowchart showing a method for manufacturing an electronic component. FIG. 6 is a diagram showing a ceramic green sheet. FIG. 7 is a front view showing a ceramic green sheet after a dividing groove forming step. FIG. 8 is a cross-sectional view of the ceramic green sheet of FIG. 7 taken along line VIII-VIII. FIG. 9 is a diagram showing a state of a crack forming step. FIG. 10 is a diagram similar to FIG. 8 showing a state of the ceramic green sheet after a crack forming step.

[0023] The ceramic substrate and the method for manufacturing an electronic component of the present invention will be described in detail below with reference to the drawings. The following exemplary embodiments are provided to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. The present invention can be modified and improved within the scope of the claims without departing from the spirit of the invention. Note that the scales of the drawings may differ from those used in the following description to facilitate understanding.

[0024] 1 is a diagram showing an example of an electronic component manufactured according to this embodiment. As shown in FIG. 1, the electronic component 1 of this embodiment is a quartz crystal resonator, and is primarily composed of a ceramic substrate 10, a conductive adhesive 51, a quartz crystal blank 52, an insulating adhesive 53, and a lid 54. In this embodiment, the conductive adhesive 51, the quartz crystal blank 52, the insulating adhesive 53, and the lid 54 are components disposed on the ceramic substrate 10, and the conductive adhesive 51 and the quartz crystal blank 52 are part of an electronic circuit.

[0025] The ceramic substrate 10 has a generally rectangular plate shape. On one side where components are arranged, a pair of terminals 11, which are part of an electronic circuit, and wiring 12, which is part of the electronic circuit and connected to each terminal 11, are provided. Castellations 13 are formed at the corners of the ceramic substrate 10. In this embodiment, the castellations 13 have a rectangular shape with quadrant-shaped corners, and side terminals 13a, which are part of the electronic circuit, are provided on the curved wall surface. A quadrant-ring electrode connected to the side terminals 13a is formed on the surface of the ceramic substrate 10 where components are arranged. The wiring 12 is connected to this quadrant-ring electrode and is electrically connected to some of the side terminals 13a. 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, wiring 12, and side terminals 13a, can be formed, for example, by applying a paste containing a conductive material (such as silver or copper) by screen printing, followed by drying and firing. The metal film may be formed by vapor deposition, sputtering, plating, etc. The metal film may be laminated, for example, by applying a paste containing a conductive material by screen printing, drying, and baking to form a metal film, and then plating may be further performed on top of the metal film.

[0026] The ceramic substrate 10 has a size of, for example, 3.2 mm (length)×2.5 mm (width)×0.25 mm (thickness).

[0027] Examples of the ceramics that make up the ceramic substrate 10 include ceramics whose main component is alumina, ceramics whose main component is aluminum nitride, ceramics whose main component is silicon nitride, and ceramics whose main component is mullite.

[0028] The conductive adhesive 51 is an adhesive having electrical conductivity, and bonds the terminal 11 and the crystal blank 52 together while the crystal blank 52 is spaced apart from the ceramic substrate 10 .

[0029] The quartz crystal blank 52 is a piezoelectric material cut to a predetermined shape, size, and angle relative to the crystal axis of the quartz crystal, and has a pair of electrodes (not shown) on its surface. These electrodes are adhered to with a conductive adhesive 51. The quartz crystal blank 52 has a natural vibration mode and a natural frequency depending on its shape, size, and cutting angle.

[0030] The insulating adhesive 53 has a generally rectangular peripheral shape when viewed from above, and is placed on the ceramic substrate 10 so as to surround the crystal blank 52. The insulating adhesive 53 may be made of an insulating double-sided tape containing insulating aggregate. The insulating adhesive 53 bonds the ceramic substrate 10 and the lid 54 together.

[0031] The lid 54 has an internal space (not shown) for housing the crystal blank 52, and is open on the ceramic substrate 10 side. The lid 54 is made of, for example, metal. By pressing the edge of the lid 54 against the insulating adhesive 53 and placing the lid 54 over the crystal blank 52, the crystal blank 52 is housed within the internal space, and the internal space is sealed.

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

[0033] Fig. 2 is a plan view of the ceramic mother substrate. As shown in Fig. 2, the ceramic mother substrate 100 has dividing sections 20 arranged in a lattice pattern, and a plurality of ceramic substrates 10 are integrated together via the dividing sections 20. An outer peripheral section 110 of the ceramic mother substrate 100 is a discarded substrate that does not become a ceramic substrate 10. The ceramic mother substrate 100 also has through-holes 13H that become castellations 13. A metal film that becomes side terminals 13a is provided on the inner peripheral surfaces of the through-holes 13H. Terminals 11 and wiring 12 are also 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 comprises 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] In this embodiment, the dividing groove 21 is generally formed as a V-groove. Therefore, the width of the dividing groove 21 is smallest at the bottom 21b. The depth of the dividing groove 21 is preferably equal to or less than half the thickness of the ceramic mother substrate 100, from the viewpoint of preventing the ceramic mother substrate 100 from undesirably cracking along the dividing portion 20 when handling the ceramic mother substrate 100. Alternatively, from the viewpoint of making it easier to break the ceramic mother substrate 100, the depth of the dividing groove 21 is preferably greater than half 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 portions 22 are portions having less strength than the ceramic substrates 10 and extend from the bottoms 21b of the dividing grooves 21 in the depth direction of the dividing grooves 21. The brittle portions 22 bond adjacent ceramic substrates 10 together. Therefore, even if adjacent ceramic substrates 10 are bonded only by the brittle portions 22, stress is required to separate the ceramic substrates 10 from each other. Therefore, the brittle portions 22 are distinguishable from cracks in which adjacent ceramic substrates 10 are in contact with each other without being bonded. The brittle portions 22 preferably extend linearly in the depth direction. However, the brittle portions 22 may extend in a curved, serpentine, or jagged manner, as long as they extend in the depth direction. The width of the brittle portions 22 is preferably smaller than the maximum width of the dividing portions 20, from the viewpoint of reducing the occurrence of burrs resulting from the brittle portions 22 remaining on the ceramic substrates 10 after singulation.

[0037] The depth of the brittle portion 22 from the bottom 21b is preferably greater than the depth of the dividing groove 21. In this case, the ceramic mother substrate 100 can be easily fractured without increasing the depth of the dividing groove 21. Alternatively, the depth of the brittle portion 22 from the bottom 21b may be smaller than the depth of the dividing groove 21. In this case, it is possible to easily prevent the ceramic mother substrate 100 from unnecessarily cracking along the dividing groove 21.

[0038] FIG. 4 is an enlarged view of the brittle portion 22 and non-brittle portion 23 surrounded by the dotted line in FIG. 3 . In FIG. 4 , the brittle portion 22 is indicated by a dashed line. As shown in FIG. 4 , the brittle portion 22 of this embodiment has larger voids 22P than the voids in the remaining portions of the brittle portion 22, and the density of the ceramic particles 10C in the brittle portion 22 is lower than in the remaining portions. In other words, the porosity is higher in the brittle portion 22 than in the remaining portions of the brittle portion 22. Furthermore, in the brittle portion 22, a portion of the ceramic particles 10C of one side of the ceramic substrate 10 separated along the dividing groove 21 and a portion of the ceramic particles 10C of the other side of the ceramic substrate 10 are sintered to each other. In FIG. 4 , a ceramic particle 10C1 of one side of the ceramic substrate 10 and a ceramic particle 10C2 of the other side of the ceramic substrate 10 are sintered to each other. The sintered particles are bonded to each other and will not separate unless stress is applied. Thus, sintered particles are distinguished from simply touching particles that can separate without the application of stress.

[0039] The non-brittle portions 23 are regions stronger than the brittle portions 22 and are located on the opposite side of the dividing grooves 21 than the brittle portions 22. In the non-brittle portions 23, the ceramic particles 10C are densely sintered, and in this embodiment, the density of the ceramic particles 10C is approximately the same as the density of the ceramic substrate 10 other than the dividing portions 20. Therefore, in this embodiment, the strength of the non-brittle portions 23 is approximately equal to the strength of the ceramic substrate 10. In this case, strength refers to strength per unit volume. Therefore, the thickness of the non-brittle portions 23 along the depth direction of the dividing grooves 21 is smaller than the thickness of the ceramic substrate 10, so the non-brittle portions 23 are easier to fracture than the ceramic substrate 10 other than the dividing portions 20.

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

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

[0042] <Preparation Step P1> This step is a step of preparing a ceramic green sheet for manufacturing a ceramic mother substrate 100. A ceramic green sheet is a raw sheet that will become a sintered ceramic body when fired, and refers to a substrate before firing. Figure 6 is a diagram showing the ceramic green sheet prepared in this step. As shown in Figure 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 ceramic, a slurry is prepared by appropriately mixing alumina powder, a sintering aid, an organic binder, a solvent, a plasticizer, and the like. Next, the prepared slurry is formed into a flat sheet by a doctor blade method, a calendar roll method, or the like. Finally, the formed sheet-like slurry is dried in a drying oven or the like to evaporate the solvent, thereby forming a single-layer ceramic green sheet 100G. The ceramic green sheet 100G may be manufactured by filling a raw material powder into a molding machine and pressure-molding it, or by other methods.

[0044] <Division Groove Forming Process P2> This process is a process of forming grooves in the ceramic green sheet 100G that will become the division grooves 21 of the ceramic mother substrate 100. Fig. 7 is a front view showing the ceramic green sheet 100G after this process, and Fig. 8 is a cross-sectional view of the ceramic green sheet 100G taken along line VIII-VIII in Fig. 7.

[0045] In this embodiment, the dividing grooves 21G are formed by, for example, pressing a blade against the ceramic green sheet 100G at positions that will become the dividing grooves 21G. At this time, to form the through holes 13HG that will become the through holes 13H, the blade is pressed against the ceramic green sheet 100G, punching out the portions that will become the through holes 13HG. The blade may be pressed against the ceramic green sheet 100G multiple times to gradually press down the bottoms 21Gb and gradually deepen the dividing grooves 21G. In this case, the type of blade may be changed every predetermined number of times. For example, the blade thickness may be reduced every predetermined number of times. Alternatively, the ceramic green sheet 100G is laser-processed to remove the portions that will become the dividing grooves 21G, thereby forming the dividing grooves 21G. At this time, to form the through holes 13HG that will become the through holes 13H, the portions of the ceramic green sheet 100G that will become the through holes 13HG are removed by laser processing. When performing laser processing, it is preferable to collect the removed debris from the ceramic green sheet 100G generated by the laser processing using a dust collector. Examples of lasers include an excimer laser, a YAG laser, and a carbon dioxide laser. Alternatively, the dividing grooves 21G and the through holes 13HG may be formed by other methods. Alternatively, the dividing grooves 21G and the through holes 13HG may be formed in separate steps. By forming the dividing grooves 21G, the regions 10G that will become the ceramic substrate 10 are formed.

[0046] <Crack Forming Process P3> This process forms cracks that will become the bases of the brittle portions 22. FIG. 9 illustrates this process, and FIG. 10 illustrates the ceramic green sheet 100G after this process, similar to FIG. 8 . As shown in FIG. 9 , the crack forming device 200 used in this process includes two belt conveyors 201 and 202 and a roller 203 positioned between the belt conveyors 201 and 202. The belt conveyors 201 and 202 are arranged so that the conveying surfaces of the ceramic green sheet 100G are at an angle of 180 degrees or more relative to each other. The belt conveyor 201 transports the ceramic green sheet 100G to the roller 203, and the belt conveyor 202 transports the ceramic green sheet 100G transported from the roller 203 to a stocker (not shown). The ceramic green sheet 100G is bent by the roller 203 so that the dividing grooves 21G widen. The bending stress at this time causes a crack 22C to form from the bottom 21Gb of the dividing groove 21G.

[0047] <Firing Step P4> This step involves firing the ceramic green sheet 100G. In this step, the ceramic green sheet 100G is laid flat so that the ceramic particles separated by the cracks 22C are in contact with each other. In this step, as described above, for example, if the ceramic substrate 10 is made of alumina ceramic, firing is performed at a predetermined temperature at which alumina can be sintered (e.g., approximately 1400°C to 1800°C). This firing sinters the ceramic green sheet 100G, and as shown in FIG. 4, some of the ceramic particles separated by the cracks 22C, i.e., ceramic particles 10C1 and 10C2, are bonded together. However, not all of the ceramic particles separated by the cracks 22C are bonded together. Therefore, voids 22P are formed during firing, forming brittle portions 22. In other words, the cracks 22C are transformed into brittle portions 22. In this way, a plurality of ceramic substrates 10 are assembled into individual pieces to obtain a ceramic mother substrate 100 in a state where the terminals 11, the wiring 12, and the side terminals 13a are not yet arranged.

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

[0049] <Cleaving Step P6> In this step, the ceramic mother substrate 100 is cleaved along the dividing grooves 21. The cleaving is performed by applying a bending stress to the ceramic mother substrate 100 to split the ceramic mother substrate 100 along the dividing grooves 21. A substrate cleaving jig is preferably used for this step. In this manner, the ceramic substrate 10 shown in FIG. 1 is obtained.

[0050] <Component Placement Process P7> This process places components on the singulated ceramic substrate 10. In this embodiment, as shown in FIG. 1 , conductive adhesive 51 is placed on the terminals 11, and the conductive adhesive 51 secures a crystal blank 52 at a distance from the ceramic substrate 10. Additionally, insulating adhesive 53 is placed on the ceramic substrate 10, and a lid 54 is secured thereto. Note that the components may be placed in a different order than described above, as long as they are ultimately placed. In this manner, a crystal resonator is obtained as the electronic component 1.

[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 dividing sections 20 having dividing grooves 21, and the dividing sections 20 include brittle sections 22 that extend from the bottoms of the dividing grooves 21 in the depth direction of the dividing grooves 21 and have a strength less than that of the ceramic substrates 10. The method for manufacturing an electronic component of this embodiment also includes a cleaving step P6 of cleaving the ceramic mother substrate 100 along the dividing grooves 21.

[0052] In the ceramic mother substrate 100 of this embodiment, the brittle portions 22 extend from the bottoms of the dividing grooves 21. Therefore, by applying stress to the ceramic mother substrate 100, the ceramic mother substrate 100 can be easily fractured along the dividing grooves 21, compared to a ceramic mother substrate that does not have the brittle portions 22. Furthermore, in this ceramic mother substrate 100, the dividing grooves 21 can be easily fractured without being formed deep. This prevents the ceramic mother substrate 100 from being unnecessarily fractured along the dividing grooves 21, compared to a case in which the dividing grooves 21 are formed to the same depth as the brittle portions 22. Therefore, the ceramic mother substrate 100 of this embodiment is easy to handle. Therefore, the method for manufacturing an electronic component of this embodiment allows electronic components to be manufactured more easily, compared to a case in which a ceramic mother substrate that does not have the brittle portions 22 is used.

[0053] Furthermore, in the ceramic mother substrate 100 of this embodiment, the dividing section 20 includes a non-brittle section 23 that is stronger than the brittle section 22 and located on the opposite side of the dividing groove 21 from the brittle section 22. By including such a non-brittle section 23 in the dividing section 20, it is possible to prevent the ceramic mother substrate 100 from being unnecessarily fractured, compared to when the brittle section 22 extends to the surface of the ceramic mother substrate 100 opposite the side where the dividing groove 21 is provided.

[0054] Furthermore, in the brittle portion 22 of this embodiment, some ceramic particles 10C1 of the ceramic particles 10C of the ceramic substrate 10 on one side divided along the dividing groove 21 and some ceramic particles 10C2 of the ceramic particles 10C of the ceramic substrate 10 on the other side are sintered to each other, resulting in a higher porosity than the rest of the brittle portion 22. With the brittle portion 22 configured in this manner, the material of the brittle portion 22 can be the same as the material of the rest of the brittle portion 22. Therefore, the configuration of the ceramic mother substrate 100 can be simplified compared to when the brittle portion 22 is made of a different material from the material of the rest of the brittle portion 22.

[0055] Although the present invention has been described above using the above-mentioned embodiment as an example, the present invention is not limited to the above-mentioned example.

[0056] For example, in the above embodiment, a quartz crystal resonator was used as an example of an electronic component. However, the electronic component according to the present invention is not limited to a quartz crystal resonator. For example, the electronic component may be a MEMS (Micro Electro Mechanical Systems), an LED (Light Emitting Diode) optical element, a chip resistor, or the like. In the case of a MEMS, for example, an electronic circuit including a gyro sensor, an acceleration sensor, or a barometric pressure sensor, and wiring, etc., is disposed on the ceramic substrate. In the case of an LED optical element, for example, an electronic circuit including an LED element and wiring, etc., is disposed on the ceramic substrate. Furthermore, in the case of a chip resistor, for example, an electronic circuit including a resistor made of silver and palladium or ruthenium oxide, and wiring, etc., is disposed on the ceramic substrate. Furthermore, the castellation 13 is not required. Therefore, the ceramic mother substrate 100 does not necessarily need to have a through-hole 13H formed therein.

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

[0058] The configuration of the brittle portion 22 may be different from that of the above embodiment. For example, the density of the ceramic particles 10C in the brittle portion 22 may be similar to that of the portions other than the brittle portion 22, and the ceramic particles 10C in the brittle portion 22 may be made of a material having a weaker bonding strength than the ceramic particles in the portions other than the brittle portion 22. In this case, for example, when forming the ceramic green sheet 100G, a material having a lower strength after sintering than the strength of the other portions is added to the position that will become the brittle portion 22.

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

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

[0061] Furthermore, when the ceramic mother substrate 100 is cleaved in the cleaving step P6, some of the electronic circuits, such as the terminals 11, the wiring 12, and the side terminals 13a, may not be disposed on the ceramic mother substrate 100. In this case, after the ceramic substrate 10 is divided into individual pieces, a pattern forming step is performed and the components are disposed.

[0062] As described above, the present invention provides a ceramic motherboard that is easy to handle and to split along the dividing grooves, and a method for manufacturing electronic components, which can be used in the field of electronic component manufacturing, etc.

Claims

1. A ceramic mother board in which a number of ceramic substrates, on which electronic circuits are arranged, are integrated via a dividing section having dividing grooves, the dividing section comprising a brittle section which extends from the bottom of the dividing groove in the depth direction of the dividing groove and has a strength less than that of the ceramic substrates.

2. The ceramic mother board according to claim 1, characterized in that the dividing section has a non-brittle section having a strength greater than that of the brittle section on the opposite side to the dividing groove side than the brittle section.

3. A ceramic mother substrate as described in claim 1 or 2, characterized in that in the brittle portion, some of the ceramic particles of the ceramic substrate on one side divided along the dividing groove and some of the ceramic particles of the ceramic substrate on the other side are sintered to each other, resulting in a higher porosity than other parts of the brittle portion.

4. The ceramic mother board according to any one of claims 1 to 3, characterized in that the width of the brittle portion is smaller than the maximum width of the dividing groove.

5. The ceramic mother board according to any one of claims 1 to 4, characterized in that the depth of said brittle portion from said bottom is greater than the depth of said dividing grooves.

6. The ceramic mother substrate according to any one of claims 1 to 4, characterized in that the depth of said brittle portion from said bottom portion is smaller than the depth of said dividing grooves.

7. A method for manufacturing electronic components, comprising: a splitting step of splitting a ceramic mother substrate, in which a plurality of ceramic substrates on which electronic circuits are arranged are integrated via a split portion having a split groove, along the split groove, wherein the split portion extends from the bottom of the split groove in the depth direction of the split groove and has a brittle portion having a strength less than that of the ceramic substrates.

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