JP2011018783A - Method of manufacturing multilayer ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a multilayer ceramic substrate, in which a product part can be largely secured by forming a margin part at a position closer to an end of a laminate.SOLUTION: The method of manufacturing the multilayer ceramic substrate includes steps of: manufacturing the laminate 10 which is formed by laminating a plurality of ceramic green layers 2 and has a center region 9, comprising the product part 11 that forms the multilayer ceramic substrate and the margin part 7 surrounding the product part 11, and an outer edge region 5 surrounding the center region 9; forming a first cut groove 13 between the center region 9 and outer edge region 5 of the laminate 10; baking the laminate 10; dividing the laminate 10 along the first cut groove 13, and removing the outer edge region 5 to obtain the center region 9; and removing the margin part 7 from the center region 9 to obtain the product part 11.

Description

  The present invention relates to a method for manufacturing a multilayer ceramic substrate formed by laminating a plurality of ceramic green layers.

  Multilayer ceramic substrates are widely used in high-frequency modules and the like because wiring patterns for mounting electronic components and passive elements such as L and C can be formed inside. In order to obtain a multilayer ceramic substrate, a plurality of ceramic green layers are laminated to produce a laminate, and this is fired. There is a case where one multilayer ceramic substrate is obtained from one laminated body, and a so-called multi-cavity method for obtaining a plurality of multilayer ceramic substrates is performed. In either case, the laminate is generally provided with a margin portion (hereinafter referred to as “margin portion”) around a product portion (hereinafter referred to as “product portion”) used as a multilayer ceramic substrate in advance. Is. Although this margin portion is not used as a product, it is used to form a position display mark or the like for mounting an electronic component on the product portion. Therefore, the margin portion must be as flat as possible.

  However, deformation such as distortion and warpage is likely to occur in the end portion of the laminate in which the margin portion is provided in the firing process. Therefore, the margin from the large deformation portion to the small deformation portion of the end portion of the laminate must be ensured, and the product portion has to be reduced accordingly.

  Therefore, conventionally, a method for suppressing deformation such as distortion and warpage of the end of the laminate in the firing process has been proposed. For example, Japanese Patent Laid-Open No. 2003-8215 (Patent Document 1) discloses a technique in which a plurality of ceramic green layers are laminated and pressure-bonded to produce a laminated body, and then an end portion of the laminated body is cut and fired. ing. This is because by cutting off the end of the laminate, the step of the end of the laminate caused by elongation or misalignment in the lamination process of the ceramic green layer is eliminated. This is a technique for suppressing deformation such as distortion at the end.

  However, even if the side end of the laminated body is cut as in Patent Document 1 to produce a laminated body without a step at the side end, the end of the laminated body is still deformed such as warping in the firing step. Will occur. This is because a force to shrink from the end toward the center acts in the planar direction and the thickness direction of the laminate. This problem is the same in a so-called non-shrink process in which a shrinkage suppression layer is disposed on both sides of a laminate and fired. In the non-shrinkage process, the shrinkage suppression layer does not substantially shrink in the firing step, so that shrinkage in the planar direction of the laminate can be substantially suppressed. However, at the end of the laminate that has a relatively large shrinking force, the shrinkage cannot be sufficiently suppressed, and the shrinkage suppression layer peels off, and deformation such as distortion and warpage occurs greatly at the end of the laminate.

  As a method for suppressing the warpage of the end portion of the multilayer body in the method of manufacturing a multilayer ceramic substrate using a non-shrinkage process, Japanese Patent Laid-Open No. 2002-185136 (Patent Document 2) focuses on the margin portion of the multilayer body. A method for suppressing warpage is disclosed. Specifically, a distance of 3 mm or more between the end of the cut groove formed between the margin part and the product part and the edge of the laminated body is ensured. That is, by not forming a cut groove in the margin portion, a force for suppressing the shrinkage of the shrinkage suppression layer in contact with the margin portion (hereinafter referred to as “shrinkage suppression force”) is exerted relatively large, so that the laminated body Deformation such as warping of the end of the is suppressed.

JP 2003-8215 A JP 2002-185136 A

  However, even with the technique disclosed in Patent Document 2, when a shrinkage suppression layer having a weak shrinkage suppression force is used, or when a non-shrinkage process is not used in the first place, that is, without firing the shrinkage suppression layer, Therefore, it is not possible to sufficiently suppress the occurrence of deformation such as large distortion and warping at the end of the laminate. Therefore, it is still necessary to secure a margin part from a large deformation part to a small deformation part of the end portion of the laminated body, and accordingly, a product part for obtaining a multilayer ceramic substrate has to be made small.

  Therefore, an object of the present invention is to provide a method for manufacturing a multilayer ceramic substrate that can solve the above-described problems.

  In order to solve the above-mentioned problems, the method for producing a multilayer ceramic substrate of the present invention first includes a step of producing a laminate. The laminate is formed by laminating a plurality of ceramic green layers containing ceramic powder. The multilayer body has a product region that is a multilayer ceramic substrate and a central region that includes a margin portion that surrounds the product portion, and further has an outer edge region that surrounds the central region. Then, the process of forming a 1st notch groove between the center area | region and an outer edge area | region of a laminated body is provided. Furthermore, the process of baking a laminated body on the sintering conditions of a ceramic powder is provided. Next, the laminated body is divided along the first cut grooves, and the outer edge region is removed to obtain a central region. Furthermore, a step of removing a margin portion from the central region to obtain a product portion is provided.

  Here, it is preferable to further include a step of post-processing the central region between the step of obtaining the central region by removing the outer edge region and the step of obtaining the product portion by removing the margin portion from the central region.

  Further, in the method for producing a multilayer ceramic substrate of the present invention, in the step of producing the laminate, one main surface and the other main surface of the laminate include inorganic material powders that are not substantially sintered under the sintering conditions of the ceramic powder. The present invention is also directed to a non-shrinkage process in which first and second shrinkage suppression layers are further laminated and fired. In this case, in the step of forming the first cut groove, the first cut groove is formed to a depth that penetrates the first shrinkage suppression layer and reaches a part of the thickness of the stacked body. After the step of firing the laminate, the method further includes a step of removing the first and second shrinkage suppression layers.

  The step of removing the first and second shrinkage suppression layers is preferably provided after the step of dividing the laminate along the first cut groove and removing the outer edge region to obtain the central region.

  Moreover, it is preferable that the manufacturing method of the multilayer ceramic substrate of this invention forms a 1st notch groove in the depth of 20 to 40% of the thickness of a laminated body.

  In addition, the method for manufacturing a multilayer ceramic substrate of the present invention further includes a step of cutting and removing the end of the multilayer body at a position outside the first cut groove before the step of firing the multilayer body. Is preferred.

  Further, in the method for manufacturing a multilayer ceramic substrate according to the present invention, the second cut groove is formed between the product portion and the margin portion and the margin portion is removed from the central region before the step of firing the multilayer body. In the step of obtaining the product portion, it is preferable to divide and remove the margin portion along the second cut groove.

  The second cut groove is preferably formed so as to reach the end of the central region.

  The second cut groove is preferably formed deeper than the first cut groove.

  Furthermore, the method for manufacturing a multilayer ceramic substrate of the present invention includes a step of forming a third cut groove inside the second cut groove before the step of firing the laminate, and the third cut is formed in the laminate. It is preferable to include a step of dividing the groove along the groove to obtain a plurality of multilayer ceramic substrates.

  According to the present invention, the first notch is formed to form the first notch groove between the center region and the outer edge region of the laminate including the outer edge region surrounding the center region composed of the product portion and the margin portion. By actively causing deformation such as distortion and warping of the laminate in the outer edge region located outside the groove, large deformation can be prevented from reaching the central region. Therefore, it becomes possible to form the margin part at a position closer to the end of the laminated body, and to secure a large product part.

  Further, when a step of post-processing the central region is further provided between the step of removing the outer peripheral region to obtain the central region and the step of removing the margin portion from the central region to obtain the product portion, distortion, warpage, etc. Since post-processing can be performed only in the central region where the deformation of the is relatively small, an effect of improving the handling property in the post-processing is obtained. Here, the handling property is improved because the laminate is easy to handle because distortion and warpage are relatively small. Since a mounting position display mark or the like is formed in the margin portion, the step of post-processing the central region is performed before the step of removing the margin portion.

  Further, in the step of producing the laminate, the first and second shrinkage suppression layers containing inorganic material powder that is not substantially sintered under the sintering conditions of the ceramic powder are further provided on one main surface and the other main surface of the laminate. In the step of laminating and forming the first cut groove, if the first cut groove is formed to a depth that penetrates the first shrinkage suppression layer and reaches a part of the thickness of the laminate, the deformation of the laminate Can be further suppressed. This is because the shrinkage suppression layer can suppress the laminate from shrinking in the planar direction.

  In addition, the step of removing the first and second shrinkage suppression layers may be provided after the step of dividing the stacked body along the first cut groove and removing the outer edge region to obtain the central region. The effect that the handling property in the removal process of a 2nd shrinkage | contraction suppression layer improves is acquired. That is, if the deformation such as distortion or warpage is relatively large, it is difficult to remove the shrinkage suppression layer because the laminate is difficult to handle, but if the outer edge region is removed, distortion or warping Since only the central region is relatively small in deformation, the laminate can be easily handled and the shrinkage suppression layer can be easily removed.

  Further, the depth of the first cut groove can be accurately divided when the thickness of the laminate is 20% or more, and when the depth is 40% or less, in the central region located inside the first cut groove. Deformations such as distortion and warpage can be made relatively small.

  Moreover, before the step of firing the laminate, if the end of the laminate is cut and removed at a position outside the first cut groove, the laminate is fired in a state where there is no step at the side end. Therefore, the generation of cracks starting from the step can be suppressed.

  In addition, in the step of forming the second cut groove between the product portion and the margin portion and removing the margin portion from the central region before the step of firing the laminate, the second cut is obtained. When the margin portion is divided and removed along the groove, the step of removing the outer edge region and the step of removing the margin portion can be easily performed.

  Further, when the second cut groove is formed so as to reach the end of the central region, the margin portion can be accurately divided.

  Further, when the second cut groove is formed deeper than the first cut groove, the division when removing the margin portion from the central region while suppressing deformation such as distortion and warpage in the central region is relatively small. Accuracy can be improved.

  And a step of forming a third cut groove inside the second cut groove before the step of firing the laminated body, and dividing the laminate along the third cut groove to form a plurality of multilayer ceramic substrates When the step of obtaining is provided, the number of multilayer ceramic substrates can be increased.

It is a schematic sectional drawing which shows the laminated body concerning the 1st Embodiment of this invention. It is a schematic top view which shows the laminated body concerning the 1st Embodiment of this invention. It is a schematic sectional drawing which shows the composite laminated body concerning the 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the composite laminated body concerning the 3rd Embodiment of this invention. It is a schematic sectional drawing which shows the composite laminated body concerning the 4th Embodiment of this invention. It is a schematic top view which shows the composite laminated body concerning the 4th Embodiment of this invention.

  Hereinafter, the manufacturing method of the multilayer ceramic substrate concerning this invention is demonstrated based on embodiment, referring FIGS. In FIG. 1 to FIG. 6, illustration of wiring conductors is omitted. Further, the dimension in the thickness direction of the laminate is exaggerated and the end portion is exaggerated in the plane direction.

<First Embodiment>
FIG. 1 and FIG. 2 are for explaining the first embodiment of the present invention, and show a laminated body 10 obtained in the process of manufacturing a multilayer ceramic substrate. In the first embodiment, a case where one multilayer ceramic substrate is obtained from one laminate 10 will be described. FIG. 1 is a schematic cross-sectional view of a laminate. FIG. 2 is a schematic top view of the laminate. Hereinafter, a method for manufacturing a multilayer ceramic substrate according to the first embodiment will be described.

(1) Preparation of laminated body First, the laminated body 10 is produced. As shown in FIG. 1, the laminated body 10 includes a plurality of laminated ceramic green layers 2.

  In order to produce the ceramic green layer 2, first, a binder, a solvent, a plasticizer, a dispersant, and the like are added to and mixed with the ceramic powder, and the mixture is thoroughly kneaded with a ball mill or the like and dispersed uniformly. A ceramic slurry is obtained by defoaming treatment. Here, as the ceramic powder, a glass-based low-temperature sintered ceramic powder obtained by mixing glass powder and ceramic powder can be used. In addition, non-glass low-temperature sintered ceramic powder that does not contain glass and precipitates glass during firing may be used during slurry.

  Next, this ceramic slurry is formed into a sheet on a carrier film so as to have a desired thickness by a casting method using a doctor blade. After drying this, it is divided so as to have a desired planar dimension, and a ceramic green layer 2 as shown in FIG. 1 is produced.

  Although not shown in FIG. 1, the ceramic green layer 2 is formed with an interlayer connection conductor, an inner conductor, and an outer conductor having a desired pattern. The interlayer connection conductor is formed by forming a through hole in the ceramic green layer 2 with a laser or the like and filling the through hole with a conductive paste. The inner conductor and the outer conductor are formed by applying a conductive paste to the surface of the ceramic green layer 2 by a method such as screen printing or ink jet printing.

  Next, this ceramic green layer 2 is laminated and pressure-bonded to produce a laminate 10. Specifically, the plurality of ceramic green layers 2 are peeled off from the carrier film, laminated, and pressure-bonded. In producing the laminate 10, a plurality of ceramic green sheets formed by the above-described casting method may be laminated, or ceramic slurry may be printed one by one as the ceramic green layer 2.

  As shown in FIGS. 1 and 2, the laminated body 10 thus manufactured includes a central region 9 and an outer edge region 5 that surrounds the central region 9 in the planar direction. The central region 9 further includes a product portion 11 and a margin portion 7 that surrounds the product portion 11 in the planar direction. However, these are all composed of the laminated body 10 in which the same ceramic green layers 2 are laminated, and the boundary is not clearly formed. Each is a conceptual region determined to have a desired plane size according to the following purposes. In particular, a first cut groove 13 described later is formed between the outer edge region 5 and the central region 9, but a dividing line 23 a is planned between the product portion 11 and the margin portion 7. A cut groove is not formed.

  Although the outer edge region 5 will be described in detail in a process described later, by firing together with the central region 9 through the first cut groove 13, a deformation such as a relatively large strain or warp is intentionally generated. This is the area to be discarded.

  The central region 9 is composed of a product portion 11 and a margin portion 7 and is located inside the outer edge region 5. Since the central region 9 is located inside the first cut groove, deformations such as distortion and warpage that occur in the firing step described later are relatively small. Therefore, the product part 11 can be made larger than before. This is because the margin portion 7 has only to have a necessary minimum size, such as forming a position display mark for mounting an electronic component. The product portion 11 is a portion that finally becomes a multilayer ceramic substrate, and is used as one multilayer ceramic substrate 1a in the first embodiment.

  As shown in FIG. 1, since the unfired laminated body 10 is produced by laminating a plurality of ceramic green layers 2, a side end portion of the laminated body 10 is caused by elongation or stacking deviation of the ceramic green layers 2. Has a step. Due to this step, deformation such as a large strain may occur in the side end portion of the laminate 10 in the firing step. Therefore, in the conventional method for manufacturing a multilayer ceramic substrate, the side end portion of the laminate 10 is eliminated in order to eliminate this step. Was removed by cutting. However, in the first embodiment, the outer edge region 5 constituting the side end portion is a portion that intentionally causes deformation, and therefore it is not always necessary to cut and remove the side end portion.

(2) Formation of Cut Groove Next, the first cut groove 13 is formed in the laminate 10. As shown in FIGS. 1 and 2, the first cut groove 13 is formed between the central region 9 and the outer edge region 5 of the stacked body 10.

  As shown in FIG. 1, the first cut groove 13 is a cut groove and is formed to a depth reaching a part of the stacked body 10, and does not completely cut the stacked body 10. This is because when completely cut, the central region 9 and the outer edge region 5 are divided, and deformation such as warpage in the firing process occurs from the end of the central region 9.

  In particular, the first cut groove 13 is preferably formed to a depth of 20% or more and 40% or less of the depth of the stacked body 10. This is because if it is 20% or more, it can be accurately divided along the first cut groove 13 after firing. Moreover, it is because deformation | transformation, such as a distortion and curvature, can be more effectively suppressed inside the 1st notch groove 13, ie, the center area | region, as it is 40% or less. However, the depth of the first cut groove 13 is not necessarily 20% or more and 40% or less.

  In addition, as shown in FIG. 1, the first cut groove 13 is tapered and formed in a V shape, but the shape of the first cut groove 13 is another shape such as a U shape. May be.

  In addition, it is preferable to form the position where the 1st notch groove 13 is formed in the position which had cut | disconnected the side edge part of the laminated body after preparation of a laminated body in the manufacturing method of the conventional multilayer ceramic substrate. Conventionally, as described above, the side end portion of the laminate has been cut and discarded in order to eliminate the step of the side end portion of the laminate caused by elongation or stacking deviation in the lamination process of the ceramic green layer. By forming the first cut groove 13 on the side, the side end can be used effectively.

  As shown in FIG. 2, the end of the first cut groove 13 reaches the end of the laminated body 10. In this respect, the terminal end of the first cut groove 13 only needs to be formed at least between the central region 9 and the outer edge region 5, and does not necessarily reach the end of the stacked body 10.

  In forming the first cut groove 13, a known method such as a method of processing with a laser, a method of pressing a cutter blade, or a method of cutting with a rotary blade can be used.

  In the first embodiment, a cut groove is not formed between the product portion 11 and the margin portion 7 in the central region 9 and is cut along the dividing line 23a after firing as will be described later. To do.

(3) Firing Next, the laminate 10 is fired. The firing conditions vary depending on the material of the laminate 10, but the firing is performed under the condition that the ceramic powder contained in the ceramic green layer 2 constituting the laminate 10 is sintered. For example, when the above-mentioned low-temperature sintered ceramic powder is used as the ceramic powder, it is fired at 800 ° C. to 1050 ° C.

  In the firing step, the binder contained in the ceramic green layer 2 constituting the laminated body 10 is removed and the ceramic powder is sintered, so that the laminated body 10 contracts in the planar direction and the thickness direction. Specifically, it shrinks toward the center of the laminate 10.

  The laminated body 10 according to the first embodiment includes an outer edge region 5 surrounding the outer periphery of the central region 9, and a first cut groove 13 is formed between the central region 9 and the outer edge region 5. One characteristic is that In other words, it is as follows. In the conventional laminate, a cut groove is formed between the product portion and the margin portion, but no cut groove is formed in the margin portion. On the other hand, in the laminated body according to the first embodiment, the first cut groove 13 is formed between the product portion and the end of the laminated body. That is, the outer edge region 5 is provided outside the product portion 11 via the margin portion 7 and the first cut groove 13.

  By firing in the state of the laminated body 10, deformation such as large distortion or warpage can be intentionally caused in the outer edge region 5. This is because, in the outer edge region 5 near the end of the laminated body 10, the first cut groove 13 becomes a starting point for causing deformation such as distortion and warpage.

  Further, the first cut groove can prevent deformation such as large distortion and warpage from reaching the central region. This is because the central region 9 and the outer edge region 5 are connected in a portion where the first notch groove 13 is not formed, and the first notch groove 13 causes deformation such as distortion and warpage in the outer edge region 5. On the other hand, the stress can be prevented from reaching the central region 9, and deformation such as large distortion and warpage can be suppressed from the central region 9.

(4) Removal of outer edge region After firing, the laminated body 10 is divided along the first cut grooves 13, and the outer edge region 5 constituting the end of the laminated body 10 is removed to obtain the central region 9. In the laminated body 10, since the central region 9 and the outer edge region 5 are formed of the same ceramic green layer 2, there is no clear boundary line, but a cut is made between the central region 9 and the outer edge region 5. Since the groove 13 is formed, it can be divided between the central region 9 and the outer edge region 5. By removing the outer edge region 5 in this way, it is possible to obtain the central region 9 with relatively small deformation such as distortion and warpage.

(5) Post-treatment The post-baking laminate 10 is subjected to post-treatments such as plating, substrate cleaning, and component mounting. When the external electrode is retrofitted, the formation of the external electrode is also included in the post-processing.

  The post-treatment may be performed before the outer edge region 5 is removed, but is preferably performed after the outer edge region 5 is removed and the central region 9 is obtained. Compared with the case where post-processing is performed including the outer edge region 5 where deformation such as distortion and warpage is relatively large, it is better in terms of handling properties to perform post-processing only in the central region 9 where deformation is relatively small. is there.

(6) Removal of Margin Part Further, the margin part 7 is removed to obtain the product part 11. In order to remove the margin part 7, it cuts with a cutter blade or a rotary blade. Alternatively, a second cut groove may be formed between the margin portion 7 and the product portion 11 in advance before the firing step, and the second cut groove may be divided along the second cut groove.

  Through the above steps, one multilayer ceramic substrate 1a can be obtained from the product portion 11 larger than the conventional product portion 11.

<Second Embodiment>
FIG. 3 is for explaining a second embodiment of the present invention, and shows a composite laminate 20 obtained in the process of manufacturing a multilayer ceramic substrate. In the second embodiment, a case where a multilayer ceramic substrate is obtained using a non-shrink process will be described. FIG. 3 is a schematic cross-sectional view showing a state in which a shrinkage suppression layer is disposed on one main surface and the other main surface of an unfired laminate. Since points that are not particularly mentioned are the same as those in the first embodiment, description thereof is omitted.

(1) Preparation of laminated body The process of producing the laminated body 10 is the same as that of 1st Embodiment.

  FIG. 3 shows a composite laminate 20 used in the second embodiment in which a first shrinkage suppression layer 4a and a second shrinkage suppression layer 4b are arranged on one main surface 6a and the other main surface 6b of the laminate 10, respectively. Is shown.

  In order to produce the first and second shrinkage suppression layers 4a and 4b, first, a binder, a solvent, a plasticizer, a dispersing agent, and the like are added to and mixed with the inorganic material powder, and then sufficiently kneaded with a ball mill or the like. And then defoaming under reduced pressure to obtain a slurry. Here, as the inorganic material powder, one that is not sintered at the sintering temperature of the ceramic powder contained in the ceramic green layer 2 is selected. For example, alumina powder or zirconia powder can be used.

  Next, the slurry is formed into a sheet on the carrier film so as to have a desired thickness by a casting method using a doctor blade. After drying this, it is divided so as to have a desired planar dimension, and first and second shrinkage suppression layers 4a and 4b as shown in FIG. 3 are produced.

  Then, the first shrinkage suppression layer 4a is disposed so as to be in contact with the one main surface 6a of the laminate 10, and the second shrinkage suppression layer 4b is disposed so as to be in contact with the other main surface 6b of the laminate 10. The body 20 is produced. In FIG. 3, the first and second shrinkage suppression layers 4a and 4b are formed one by one, but a plurality of layers may be stacked. Further, the first and second shrinkage suppression layers 4 a and 4 b may be formed by printing in the same manner as the stacked body 10.

(2) Formation of Cut Groove As shown in FIG. 3, a first cut groove 13 is formed in the composite laminate 20. The first cut groove 13 is formed to a depth that penetrates the first shrinkage suppression layer 4 a and reaches a part of the thickness of the unfired stacked body 10. The first cut groove 13 penetrates the first shrinkage suppression layer 4a and is formed only in a depth reaching a part of its thickness without penetrating the first shrinkage suppression layer 4a. In this case, the outer edge region 5 of the laminate 10 cannot be divided with high accuracy. This is because the first shrinkage suppression layer 4 a after firing the laminated body 10 is in a porous state without being sintered, and the first cut groove 13 does not function as a starting point for dividing the laminated body 10. In addition, the reason why it is formed to a depth that reaches a part of the thickness of the unfired laminated body 10 is that the outer edge region 5 and the central region 9 of the laminated body 10 are divided when the laminated body 10 is penetrated. This is because a relatively large deformation occurs in the central region 9.

  Specifically, as in the first embodiment, the first cut groove 13 is preferably formed to a depth of 20% to 40% of the depth of the stacked body 10.

  In addition, you may arrange | position the 1st and 2nd shrinkage | contraction suppression layers 4a and 4b in the laminated body 10 in which the 1st notch groove 13 was formed previously. However, since the 1st notch 13 cannot be recognized after baking, in order to divide | segment accurately, it is forming the 1st notch 13 in the state of the composite laminated body 20 which has arrange | positioned the shrinkage | contraction suppression layer. preferable.

(3) Firing Next, the composite laminate 20 is fired. In the composite laminate 20, first and second shrinkage suppression layers 4a and 4b containing an inorganic material powder that does not substantially sinter in the firing step are disposed on one main surface 6a and the other main surface 6b of the laminate 10. Therefore, in the firing step, the first and second shrinkage suppression layers 4a and 4b are not substantially sintered and do not shrink. Therefore, the laminate 10 sandwiched between the first and second shrinkage suppression layers 4a and 4b is substantially suppressed by the first and second shrinkage suppression layers 4a and 4b from attempting to shrink in the planar direction. It shrinks only in the thickness direction. As a result, the dimensional accuracy in the planar direction of the laminated body 10 after firing can be improved, and deformations such as distortion and warpage of the laminated body 10 can be made relatively small.

(4) Removal of outer edge region Then, as in the first embodiment, the laminated body 10 is divided along the first cut grooves 13, and the outer edge region 5 is removed to obtain the central region 9. Although the shrinkage suppression layer after firing is substantially not sintered and is in a porous state, the first cut groove 13 is formed to a depth that reaches a part of the thickness of the laminate 10. The composite laminate 20 can be divided along the first cut grooves 13. At this time, the shrinkage suppression layer may not be accurately divided between the outer edge region and the central region. This is because the shrinkage suppression layer is finally removed as will be described later.

(5) Post-treatment After firing, the first and second shrinkage suppression layers 4a and 4b are removed. Since the first and second shrinkage suppression layers 4a and 4b are in a porous state, they can be removed by a method such as ultrasonic cleaning or blasting. Thereby, the center area | region 9 of the laminated body 10 can be obtained.

  The first and second shrinkage suppression layers 4a and 4b are removed after the laminated body 10 is divided along the first cut grooves 13 and the outer edge region 5 is removed to obtain the central region 9. Is preferred. This is because it is easier to remove the first and second shrinkage suppression layers 4a and 4b. That is, if the first and second shrinkage suppression layers 4a and 4b are removed while leaving the outer edge region 5 with relatively large deformation such as distortion and warping, the handling property of the composite laminate 20 is not good, and thus the shrinkage suppression layer. It becomes difficult to remove. On the other hand, after the outer edge region 5 is removed, only the central region 9 having a small deformation such as distortion or warping is provided, and thus the handling property is good and the shrinkage suppression layer is easily removed.

(6) Removal of Margin Part Similarly to the first embodiment, the margin part 7 is removed to obtain a product part 11 that becomes a multilayer ceramic substrate.

<Third Embodiment>
FIG. 4 is a schematic cross-sectional view of a composite laminate 30 obtained in the process of manufacturing a multilayer ceramic substrate for explaining a third embodiment of the present invention.

  Since steps (1) to (6) are the same as those in the second embodiment, the description thereof is omitted.

  As shown in FIG. 4, in the third embodiment, the composite laminate 30 is manufactured at the position 3 outside the first cut groove 13 with respect to the composite laminate 30 produced in the same process as the second embodiment. Disconnect. This is to eliminate a step at the side end portion of the composite laminate 30 caused by elongation or misalignment in the lamination process of the ceramic green layer 2 and the first and second shrinkage suppression layers 4a and 4b. This is because if the composite laminate 30 is fired with a step, a crack is generated starting from the step, and the crack may develop to the product portion 11. Therefore, this step is performed before the step of firing the composite laminate 30.

<Fourth Embodiment>
5 and 6 illustrate a fourth embodiment of the present invention, and show a composite laminate 40 obtained in the process of manufacturing a multilayer ceramic substrate. In the fourth embodiment, a so-called multi-cavity case in which a plurality of multilayer ceramic substrates 1b are obtained from one composite laminate 40 will be described. FIG. 5 is a schematic cross-sectional view of an unfired composite laminate. FIG. 6 is a schematic top view of an unfired composite laminate.

  Since steps (1) to (6) are the same as those in the second embodiment, the description thereof is omitted. Moreover, the point which cut | disconnects the edge part of the composite laminated body 40 in the position 3 outside the 1st notch groove 13 similarly is the same as that of 3rd Embodiment. However, the step of disposing the shrinkage suppression layer and the step of cutting the end of the composite laminate are not essential steps in the fourth embodiment.

  As shown in FIG. 5, in the composite laminate 40 according to the fourth embodiment, a second cut groove 23 is further formed inside the first cut groove 13. Specifically, a second cut groove 23 is formed between the margin portion 7 and the product portion 11 in the central region 9 inside the first cut groove 13.

  Further, a third cut groove 33 for dividing the product portion 11 as a collective substrate into a plurality of multilayer ceramic substrates 1b is formed inside the second cut groove 23 as necessary.

  It is preferable that the second cut groove 23 and the third cut groove 33 are formed at the same depth as the first cut groove 13 in that they can be formed without changing the conditions in the step of forming the cut groove.

  However, as shown in FIG. 5, for example, the first cut groove 13 is formed to a depth of 20% of the stacked body 10, and the second cut groove 23 is formed to a depth of 60% of the stacked body 10. For example, the second cut groove 23 may be formed deeper than the first cut groove 13. The reason is as follows. First, the deeper the notch groove, the greater the deformations such as distortion and warpage occur inside, but the division accuracy is improved. In this case, the depth of the first cut groove 13 should be set shallower in consideration of the deformation on the inner side of the division accuracy. This is because the first cut groove 13 is formed in order to prevent a large deformation from occurring in the inner central region 9. Moreover, since the margin part 7 which comprises the inner side of the 1st notch groove 13 is a part finally discarded, it is because the necessity which attaches importance to the precision of division | segmentation is low. On the other hand, since the second cut groove 23 is formed in the central region 9 where deformation such as distortion and warpage is relatively small in the first place, the deformation is also generated on the inner side regardless of the depth of the second cut groove 23. Relatively small. Moreover, since the inside of the 2nd cut groove 23 is the product part 11 and is the multilayer ceramic substrate 1b, the precision of a division | segmentation is calculated | required. Therefore, it is preferable that the second cut groove 23 is set deeper with emphasis on the accuracy of division.

  The first cut groove 13 and the second cut groove 23 may be formed on separate main surfaces.

  In addition, as shown in FIG. 6, the second cut groove 23 is preferably formed so as to reach the end of the central region 9. In order to divide along the second cut groove 23 and remove the margin part 7 from the central region 9, the accuracy of the division is improved when the second cut groove 23 reaches the end of the central region 9. Because. Since the central region 9 has little deformation such as distortion and warpage, the second cut groove 23 can be formed with emphasis on the accuracy of division. However, the first cut groove 13 does not have to reach the end of the composite laminate 40.

  Further, as shown in FIG. 6, the third cut groove 33 for dividing the product portion 11 into the plurality of multilayer ceramic substrates 1 b reaches at least the end of the product portion 11. First, when all the margin portion 7 is removed along the second cut groove 23 and then the product portion 11 is divided along the third cut groove 33, the third cut groove 33 is formed on the product portion 11. It only has to reach the end. In addition, when the second cut groove 23 and the third cut groove 33 are all divided in the vertical direction or the horizontal direction, and then divided in the horizontal direction or the vertical direction, regardless of the division order. The third cut groove 33 preferably reaches the end of the central region 9.

  Since the fourth embodiment is a case of a collective substrate, the fact that a large product portion 11 can be secured means that the number of multilayer ceramic substrates 1b can be increased.

  Examples performed to confirm the effects of the present invention will be described below. An Example is performed based on 3rd Embodiment. This will be described in detail below.

A glass powder obtained by mixing each powder of SiO ₂ , CaO, Al ₂ O ₃ and B ₂ O ₃ was mixed with an alumina powder. To this mixed powder, toluene, butanol, and xylene were added, mixed, dispersed, and defoamed as an acrylic organic binder and solvent to obtain a ceramic slurry. Next, the slurry was formed into a sheet shape on a carrier film by applying a casting method using a doctor blade to produce a ceramic green layer 2 having a thickness of 100 μm, and after the ceramic green layer was dried, The entire carrier film was divided so that the planar dimension was 150 mm □.

  On the other hand, to the alumina powder, polyvinyl butyral as an organic binder and toluene, ethanol as a solvent were added, mixed, dispersed, and defoamed to obtain a slurry. Next, the slurry was formed into a sheet, dried and divided by the same method as for the ceramic green layer to produce a shrinkage suppression layer having a thickness of 70 μm and a planar dimension of 150 mm □.

  Next, the above-described 10 ceramic green layers are laminated to produce a laminate, and two shrinkage suppression layers are laminated so as to sandwich the laminate, and are pressed in the laminating direction so that the plane dimension is reduced. An unfired composite laminate having a size of 150 mm □ was obtained.

  Next, four first cut grooves parallel to each edge were formed at a position of 52.5 mm from the center of the unfired composite laminate. The depth of the first cut groove was formed so as to reach a part of the thickness of the multilayer substrate while penetrating one shrinkage suppression layer in the thickness direction. Specifically, it formed according to the conditions shown in Table 1. Then, it cut | disconnected in parallel with respect to each edge at the position of 62.5 mm from the center of an unbaked composite laminated body, and obtained the unbaked composite laminated body (samples 1-4) of 125 mm □. The end of the first cut groove is present on the edge of the 125 mm □ composite laminate.

  Furthermore, as a comparative example, the laminate was cut in parallel to each edge at a position 52.5 mm from the center of the unfired composite laminate to obtain a 105 mm □ unfired composite laminate (Sample 5).

  Subsequently, the composite laminated body which concerns on each of the samples 1-5 was baked at 900 degreeC, and the part of the laminated body was sintered.

  Further, the 125 mm □ composite laminate of Samples 1 to 4 was divided along four cut grooves at a position 52.5 mm from the center to obtain a 105 mm □ composite laminate.

  And the shrinkage | contraction suppression layer in both surfaces of the composite laminated body of samples 1-5 was removed, and the center area | region of the laminated body for evaluation was obtained.

  The warpage amount of the central region of the produced laminate was evaluated by the following method.

  First, the thickness of the central part of the central region of the laminate is measured with a caliper or the like. Next, a glass plate of 200 mm □ and a glass plate of 200 mm × 40 mm are prepared, a metal plate having a known thickness is sandwiched between the two glass plates, and fixed with an alligator clip to produce a gap gauge. Pass through the central area of the laminate through the gap gauge and evaluate whether it passes completely. For example, when a 0.500 mm thick multilayer substrate passes through a 0.700 mm gap and does not pass through a 0.690 mm gap, the warpage is considered to be 0.190 mm to 0.200 mm. The warp amount was 0.200 mm on the larger side. Table 1 shows the amount of warpage of each sample.

  As is apparent from the results in Table 1, the amount of warpage of the substrate is reduced in Samples 1 to 4 according to the present invention compared to Sample 5 using the conventional method. In addition, the warp reduction effect is higher as the depth of the first cut groove is smaller. If the depth of the cut groove is in the range of 20% or more and 40% or less, the warpage amount can be suppressed to 50% or less as compared with the conventional method.

DESCRIPTION OF SYMBOLS 1a, 1b Multilayer ceramic substrate 2 Ceramic green layer 4a, 4b 1st and 2nd shrinkage | contraction suppression layer 5 Outer edge area | region 6a, 6b The main surface of a laminated body 7 Margin part 9 Central area | region 10 Laminated body 11 Product part 13 1st notch Groove 20, 30, 40 Composite laminate 23 Second cut groove

Claims (10)

A laminate comprising a plurality of ceramic green layers containing ceramic powder and having a center region composed of a product portion to be a multilayer ceramic substrate and a margin portion surrounding the product portion, and an outer edge region surrounding the center region. A manufacturing process;
Forming a first cut groove between the central region and the outer edge region of the laminate;
Firing the laminate under sintering conditions of the ceramic powder;
Dividing the laminate along the first cut groove, removing the outer edge region to obtain the central region;
Removing the margin part from the central region to obtain the product part;
A method for producing a multilayer ceramic substrate.   The method further comprises a step of post-processing the central region between the step of removing the outer edge region to obtain the central region and the step of removing the margin portion from the central region to obtain the product portion. Item 2. A method for producing a multilayer ceramic substrate according to Item 1. In the step of producing the laminate, the first and second shrinkage suppression layers containing inorganic material powder that is not substantially sintered under the sintering condition of the ceramic powder on one main surface and the other main surface of the laminate. Laminate further,
In the step of forming the first cut groove, the first cut groove is formed to a depth that penetrates the first shrinkage suppression layer and reaches a part of the thickness of the stacked body,
The manufacturing method of the multilayer ceramic substrate of Claim 1 or 2 further equipped with the process of removing the said 1st and 2nd shrinkage | contraction suppression layer after the process of baking the said laminated body.   The step of removing the first and second shrinkage suppression layers is provided after the step of dividing the laminated body along the first cut groove and removing the outer edge region to obtain the central region. Item 4. A method for producing a multilayer ceramic substrate according to Item 3.   5. The method for manufacturing a multilayer ceramic substrate according to claim 1, wherein the first cut groove is formed at a depth of 20% to 40% of the thickness of the multilayer body.   6. The method according to claim 1, further comprising a step of cutting and removing an end portion of the stacked body at a position outside the first cut groove before the step of firing the stacked body. For producing a multilayer ceramic substrate. Before the step of firing the laminate, further comprising a step of forming a second cut groove between the product portion and the margin portion,
7. The multilayer according to claim 1, wherein in the step of removing the margin portion from the central region to obtain the product portion, the margin portion is divided and removed along the second cut groove. A method for manufacturing a ceramic substrate.   The method for manufacturing a multilayer ceramic substrate according to claim 7, wherein the second cut groove is formed so as to reach an end of the central region.   The method of manufacturing a multilayer ceramic substrate according to claim 7 or 8, wherein the second cut groove is formed deeper than the first cut groove. Before the step of firing the laminate, further comprising the step of forming a third cut groove inside the second cut groove,
The method for manufacturing a multilayer ceramic substrate according to claim 7, further comprising a step of dividing the multilayer body along the third cut groove to obtain a plurality of multilayer ceramic substrates.