JP4363102B2 - Manufacturing method of multilayer capacitor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a multilayer capacitor.
[0002]
[Prior art]
A multilayer ceramic capacitor is manufactured, for example, by printing a plurality of capacitor electrodes on the surface of a mother ceramic green sheet, and laminating a plurality of the ceramic green sheets of the mother and pressing them together to form an unfired mother. The press forming process for forming the ceramic multilayer block, the mother ceramic multilayer block is cut according to the arrangement of the capacitor electrodes, the cutting process for cutting out the individual multilayer ceramic capacitors, the process for firing the cut multilayer ceramic capacitors, and the firing A process of forming external electrodes on the multilayer ceramic capacitor is sequentially performed.
[0003]
The multilayer ceramic capacitors manufactured in this way are all or are extracted, and the electrostatic capacity is measured, and the non-defective product and the defective product are selected.
[0004]
In addition, although it is not a selection method by capacitance measurement, Patent Document 1 to Patent Document are methods for selecting good products and defective products by observing the appearance of the multilayer ceramic capacitor or the stacking misalignment detection mark exposed on the cut surface. 3.
[0005]
[Patent Document 1]
Japanese Patent No. 2678393 [Patent Document 2]
JP-A-7-201641 [Patent Document 3]
JP-A-8-56062 [0006]
[Problems to be solved by the invention]
However, measuring the capacitance of all multilayer ceramic capacitors is a very complicated operation. In particular, in the case of a monolithic ceramic capacitor having a small size, in addition to being difficult to handle, high precision measurement is required, which is further complicated. Furthermore, since the measurement terminal is applied to the external electrode of the multilayer ceramic capacitor during measurement, there is a problem that the external electrode is damaged by the measurement terminal.
[0007]
On the other hand, when a predetermined number is extracted from the population of the multilayer ceramic capacitors and the electrostatic capacity is measured, the handling is statistical. Therefore, in order to increase the reliability of measurement, it is necessary to increase the number of samplings, and although it is smaller than the total number measurement, it still takes a long time for the measurement.
[0008]
SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a multilayer capacitor capable of efficiently performing pass / fail selection by capacitance measurement.
[0009]
[Means and Actions for Solving the Problems]
In order to achieve the above object, a method of manufacturing a multilayer capacitor according to the present invention includes:
(A) stacking a plurality of insulating layers and a plurality of capacitor electrodes, and forming a mother multilayer block from which a plurality of multilayer capacitors can be taken out by dividing along a predetermined dividing line;
(B) Among a plurality of multilayer capacitors, two or more specific multilayer capacitors disposed so as to surround a region for obtaining the capacitance distribution, or two or more specific multilayer capacitors disposed in a peripheral portion of the region The capacitance of the multilayer capacitor is measured, and the capacitance of the multilayer capacitor disposed between the specific multilayer capacitors is obtained based on the measured capacitance value. Determining the capacitance distribution;
(C) separating each multilayer capacitor of the mother multilayer block based on the capacitance distribution;
It is provided with.
[0010]
According to the above method, it is possible to select all the multilayer capacitors of the mother multilayer block by measuring the capacitance with respect to a small number of specific multilayer capacitors.
[0011]
Here, the capacitance of the specific multilayer capacitor may be measured before dividing the mother multilayer block along a predetermined dividing line. Thereby, since the capacitance is measured in the state of the mother multilayer block, it is possible to perform selection while maintaining the positional relationship between the multilayer capacitors, and the handling of the multilayer capacitors becomes extremely easy.
[0012]
The capacitance of the specific multilayer capacitor may be measured after dividing the mother multilayer block along a predetermined dividing line. Alternatively, the process may be performed after the mother multilayer block is divided along a predetermined dividing line and a plurality of multilayer capacitors connected in a strip shape are taken out from the mother multilayer block. In these cases, each multilayer capacitor is taken out from the mother multilayer block so that the arrangement position in the mother multilayer block can be specified.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a method for manufacturing a multilayer capacitor according to the present invention will be described below with reference to the accompanying drawings.
[0014]
[First Embodiment, FIGS. 1 to 5]
FIG. 1 is a plan view showing an example of a mother ceramic green sheet 10 for manufacturing a multilayer capacitor. The mother ceramic green sheet 10 is printed with a large number of capacitor electrodes 11 and four pre-measurement capacitor electrodes 12a to 12d cut out in a later step. The capacitor electrodes 11 are arranged in a grid pattern. The mother ceramic green sheet 10 is manufactured in the form of a sheet by a method such as a doctor blade method by adding a solvent or a binder to the ceramic powder and kneading.
[0015]
Preliminary measurement capacitor electrodes 12 a to 12 d are arranged on the outer peripheral portion (near the central portions of the four sides) of the rectangular mother ceramic green sheet 10. The pre-measurement capacitor electrodes 12a to 12d are for measuring the capacitance in advance of the product, and have the same area and the same as the capacitor electrode outside the region where the capacitor electrode 11 is disposed. It is formed with a coating thickness.
[0016]
In addition, you may use the capacitor electrodes 11a-11d near each center part of 4 sides of the sheet | seat 10 as a capacitor electrode for prior measurement. However, when the pre-measurement capacitor electrodes 12a to 12d are formed outside the capacitor electrode 11, the distance between the pre-measurement capacitor electrodes becomes longer, and the capacitance distribution of the multilayer capacitor determined in a later step is more accurate. Become.
[0017]
As shown in FIG. 2, a plurality of mother ceramic green sheets 10 are stacked while being alternately shifted in the X direction, and further, protective mother ceramic green sheets having no capacitor electrode formed thereon are stacked. Thereafter, the mother ceramic laminated block 9 is formed by pressure bonding. However, in FIG. 2, the protective mother ceramic green sheets disposed on the top and bottom are omitted. The same applies to FIGS. 3 to 5 below.
[0018]
Next, after the mother ceramic multilayer block 9 is fired, via holes are formed in the lead portions of the pre-measurement capacitor electrodes 12a to 12d using a laser beam or the like. By filling the holes with a conductive paste such as Ag, Pd, Cu, Au or an alloy thereof, via holes 13a and 13b for external electrodes are formed as shown in FIG. The mother ceramic multilayer block 9 may be fired after the formation of the external electrode via holes 13a and 13b.
[0019]
The pre-measurement capacitor electrodes 12a are opposed to each other with the sheet 10 therebetween, and a pre-measurement multilayer capacitor 14a is formed between the external electrode via holes 13a and 13b. Similarly, the pre-measurement capacitor electrodes 12b, 12c, and 12d also form pre-measurement multilayer capacitors 14b, 14c, and 14d between the external electrode via holes 13a and 13b, respectively. On the other hand, the capacitor electrodes 11 are opposed to each other with the sheet 10 interposed therebetween to form a multilayer capacitor (product) 15.
[0020]
Next, the capacitance is measured by applying a measurement terminal to the external electrode via holes 13a and 13b of each of the multilayer capacitors for pre-measurement 14a to 14d. Then, the capacitance distribution of the multilayer capacitor 15 in the mother ceramic multilayer block 9 is estimated and determined from the capacitance of each of the prior measurement multilayer capacitors 14 a to 14 d and the arrangement relationship in the mother ceramic multilayer block 9.
[0021]
For example, as shown in FIG. 4, it is assumed that the capacitances of the pre-measurement multilayer capacitors 14a to 14d are x1pF, x2pF, y1pF, and y2pF, respectively. Then, the electrostatic capacity zpF of the multilayer capacitor 15a located at the center of the mother ceramic multilayer block 9 is the electrostatic capacity xpF in the X direction estimated from x1pF and x2pF, and the electrostatic capacity in the Y direction estimated from y1pF and y2pF. It is set as an average value with the capacitance ypF. Based on the capacitance (x + y) / 2pF of the multilayer capacitor 15a and the capacitances x1pF, x2pF, y1pF, y2pF of the four prior measurement multilayer capacitors 14a to 14d, equal capacitance lines (equal to A line connecting the capacitance positions) A1 to A5 is drawn, and the capacitance distribution is estimated for each column or each region.
[0022]
Next, based on the obtained electrostatic capacitance distribution, each multilayer capacitor 15 of the mother ceramic multilayer block 9 is judged as good or bad. Then, the multilayer capacitor 15 determined to be non-defective is taken out from the mother ceramic multilayer block 9 by being divided along the dividing line C as shown in FIG. More specifically, when the capacitances of the prior measurement multilayer capacitors 14a to 14d are x1 = 1 pF, x2 = 5 pF, y1 = 3 pF, y2 = 3 pF, and 4 to 5 pF are in the non-defective range, x1, x2 , Y1 and y2 from the gradient (distribution) of the capacitances, the two columns on the right side of FIG. External electrodes 21 and 22 are formed on the left and right end faces of the multilayer capacitor 15 taken out.
[0023]
According to the above method, it is possible to select all of the multilayer capacitors 15 of the mother multilayer block 9 by simply measuring the capacitances of the four prior measurement multilayer capacitors 14a to 14d. Therefore, the sorting process time can be shortened.
[0024]
Further, since it is not necessary to apply a terminal for measuring the electrostatic capacitance to the external electrodes 21 and 22 of the multilayer capacitor 15 as a product, there is no fear that the external electrodes 21 and 22 are damaged by the measurement terminals.
[0025]
Furthermore, since the capacitance is measured in the state of the mother laminated block 9, it becomes easy to handle. Further, since the external electrodes 21 and 22 are formed only for non-defective products, the manufacturing cost can be reduced. Note that the greater the number of prior measurement multilayer capacitors, the higher the estimated accuracy of the capacitance distribution.
[0026]
[Second Embodiment, FIG. 6]
Another embodiment of the method for manufacturing a multilayer capacitor will be described. As shown in FIG. 6, a plurality of mother ceramic green sheets 10 shown in FIG. 1 are stacked while being alternately shifted, and further, protective mother ceramic green sheets are stacked on the top and bottom thereof. However, in FIG. 6, the protective mother ceramic green sheets arranged on the top and bottom are omitted. Thereafter, the mother ceramic laminated block 9 is formed by pressure bonding.
[0027]
The mother ceramic multilayer block 9 is temporarily fixed to the adhesive sheet and then cut along a predetermined dividing line C to be divided into individual multilayer capacitors 14a to 14d and 15. Even after the division, the individual multilayer capacitors 14 a to 14 d and 15 are temporarily fixed to the adhesive sheet, and the arrangement position in the mother multilayer block 9 can be specified for each of the multilayer capacitors 14 a to 14 d and 15. Thereafter, only the pre-measurement multilayer capacitors 14a to 14d are taken out, fired in advance, and the external electrodes 21 and 22 are formed to complete the pre-measurement multilayer capacitors 14a to 14d.
[0028]
Next, the capacitance is measured by applying a measurement terminal to the external electrodes 21 and 22 of each of the prior measurement multilayer capacitors 14a to 14d. Then, the capacitance distribution of the multilayer capacitor 15 in the mother ceramic multilayer block 9 is estimated and determined from the capacitance of each of the prior measurement multilayer capacitors 14 a to 14 d and the arrangement relationship in the mother ceramic multilayer block 9.
[0029]
Next, based on the obtained electrostatic capacitance distribution, each multilayer capacitor 15 of the mother ceramic multilayer block 9 is judged as good or bad. Then, only the multilayer capacitor 15 determined to be non-defective is taken out from the adhesive sheet and baked to form the external electrodes 21 and 22 to complete the multilayer capacitor (product) 15.
[0030]
The method for manufacturing the multilayer capacitor 15 described above has the same effects as those of the first embodiment.
[0031]
[Third Embodiment, FIGS. 7 and 8]
Another embodiment of the method for manufacturing a multilayer capacitor will be described. As shown in FIG. 7, a plurality of mother ceramic green sheets (not provided with the pre-measurement capacitor electrodes 12a to 12d) 10 shown in FIG. 1 are stacked while being alternately shifted. Stack ceramic green sheets. In FIG. 7, the protective mother ceramic green sheets disposed on the upper and lower sides are omitted. Thereafter, the mother ceramic laminated block 9 is formed by pressure bonding.
[0032]
Next, a via hole is formed in the lead-out portion of the capacitor electrode 11 using a laser beam or the like. By filling the hole with a conductive paste such as Ag, Pd, Cu, Au or an alloy thereof, the via hole 16 for the external electrode is formed.
[0033]
Next, the mother ceramic multilayer block 9 is cut along the dividing line C while holding the suction chuck or the like on the cut table so that the arrangement position in the mother ceramic multilayer block 9 can be understood. Are divided into strip-shaped multilayer blocks 17 connected to the multilayer capacitor 15. The external electrode via hole 16 is divided into two to be external electrodes.
[0034]
In this state, it is transferred to another suction chuck and transferred onto the baking plate. After firing in a state where the arrangement position in the mother ceramic multilayer block 9 is known, only the predetermined multilayer block 17 is taken out, and the electrostatic capacity distribution is estimated and determined by the above-described method. Based on the obtained electrostatic capacitance distribution, each multilayer capacitor 15 of the mother ceramic multilayer block 9 is judged good or bad. Then, by dividing only the multilayer capacitor 15 determined to be non-defective along the dividing line C, the multilayer capacitor (product) 15 is cut out from the multilayer block 17 and completed.
[0035]
This manufacturing method is preferable because the multilayer capacitor 15 used for pre-measurement and the multilayer capacitor 15 that is the product are fired under the same conditions, so that variations in capacitance due to firing lots are eliminated.
[0036]
[Other Embodiments]
In addition, this invention is not limited to the said embodiment, It can change variously within the range of the summary. The multilayer capacitor may be built in a composite part such as a multilayer LC filter or a high-frequency module.
[0037]
As shown in FIG. 9, in the case of a relatively large capacitor electrode 11, the pre-measurement capacitor electrodes 12 a to 12 d may be set to a size smaller than the capacitor electrode 11. In this case, it is necessary to confirm the capacitance ratio between the multilayer capacitor 15 and the preliminary measurement multilayer capacitors 14a to 14d, which are respectively prepared by the capacitor electrode 11 and the preliminary measurement capacitor electrodes 12a to 12d. Based on the ratio, the capacitance distribution is estimated and determined by the method of the embodiment. Thereby, since the influence of the lamination accuracy can be amplified and confirmed by the prior measurement multilayer capacitors 14a to 14d, it is possible to estimate the capacitance with high accuracy.
[0038]
Furthermore, in the above embodiment, the quality distribution is determined by measuring the capacitance distribution. However, the determination is not limited to the case of dividing the product into non-defective products and defective products, and each column or each is determined based on the obtained capacitance distribution. The multilayer capacitors may be classified according to characteristics for each region.
[0039]
The capacitor electrodes 11 may be arranged in a zigzag pattern instead of a lattice shape, and the mother ceramic green sheets 10 may be stacked while being alternately shifted in the Y direction or the oblique direction instead of the X direction.
[0040]
Moreover, when manufacturing a multilayer capacitor, it is not necessarily limited to the construction method which laminates | stacks the ceramic sheet | seat provided with the conductor pattern, and bakes it integrally. A ceramic sheet fired in advance may be used. Moreover, you may manufacture a multilayer capacitor with the construction method demonstrated below. That is, after a paste-like ceramic material is applied by a technique such as printing to form a ceramic layer, a paste-like conductive material is applied on the ceramic layer to form a conductor pattern. Further, a paste-like ceramic material is applied from above to form a ceramic layer. A capacitor having a multilayer structure can be obtained by sequentially applying in this manner.
[0041]
【The invention's effect】
As is clear from the above description, according to the present invention, the capacitance of a specific multilayer capacitor among a plurality of multilayer capacitors is measured, and a specific multilayer capacitor is measured based on the measured capacitance value. The capacitance of the multilayer capacitor placed in is obtained, and the capacitance distribution of the multilayer capacitor in the mother multilayer block is estimated and determined. All the multilayer capacitors in the mother multilayer block can be separated.
[Brief description of the drawings]
FIG. 1 is a plan view showing a first embodiment of a method of manufacturing a multilayer capacitor according to the present invention.
FIG. 2 is a plan view showing a manufacturing procedure following FIG.
3 is a plan view showing a manufacturing procedure subsequent to FIG. 2. FIG.
4 is a plan view showing a manufacturing procedure subsequent to FIG. 3. FIG.
5 is a plan view showing a manufacturing procedure following FIG. 4. FIG.
FIG. 6 is a plan view showing a second embodiment of the method for manufacturing the multilayer capacitor in accordance with the present invention.
FIG. 7 is a plan view showing a third embodiment of the method for manufacturing the multilayer capacitor in accordance with the present invention.
FIG. 8 is a perspective view showing a manufacturing procedure following FIG. 7;
FIG. 9 is a plan view showing another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 9 ... Mother ceramic multilayer block 10 ... Mother ceramic green sheet 11 ... Capacitor electrodes 12a-12d ... Pre-measurement capacitor electrodes 14a-14d ... Pre-measurement multilayer capacitor 15 ... Multi-layer capacitor

Claims (5)

A step of stacking a plurality of insulating layers and a plurality of capacitor electrodes, and forming a mother multilayer block from which a plurality of multilayer capacitors can be taken out by dividing along a predetermined dividing line;
Among the plurality of multilayer capacitors, two or more specific multilayer capacitors disposed so as to surround a region for obtaining a capacitance distribution, or two or more specific multilayer capacitors disposed in the periphery of the region And measuring the capacitance of the multilayer capacitor disposed between the specific multilayer capacitors based on the measured capacitance value, and determining the capacitance of the multilayer capacitor of the mother multilayer block. Determining a volume distribution;
Separating each multilayer capacitor of the mother multilayer block based on the capacitance distribution;
A method for producing a multilayer capacitor, comprising: The method of manufacturing a multilayer capacitor according to claim 1, wherein the capacitance of the specific multilayer capacitor is measured before the mother multilayer block is divided along a predetermined dividing line. When individually taking out a plurality of multilayer capacitors by dividing the mother multilayer block along a predetermined dividing line, it is taken out so that the arrangement position in the mother multilayer block can be specified for each multilayer capacitor,
The capacitance measurement of the specific multilayer capacitor is performed after dividing the mother multilayer block along a predetermined dividing line,
The method for manufacturing a multilayer capacitor according to claim 1. When taking out a plurality of multilayer capacitors connected in a strip shape by dividing the mother multilayer block along a predetermined dividing line, it is taken out so that the arrangement position in the mother multilayer block can be specified for each multilayer capacitor,
The capacitance measurement of the specific multilayer capacitor is performed after the mother multilayer block is divided along a predetermined dividing line and a plurality of multilayer capacitors connected in a strip shape are taken out from the mother multilayer block. ,
The method for manufacturing a multilayer capacitor according to claim 1.   The mother multilayer block is provided with two or more capacitance measuring multilayer capacitors, the capacitance of the capacitance measuring multilayer capacitor is measured, and the capacitance measurement is performed based on the measured capacitance value. 5. The capacitance distribution of the multilayer capacitors of the mother multilayer block is determined by calculating the capacitance of the multilayer capacitors disposed between the multilayer capacitors for use. 5. A method for producing the multilayer capacitor according to claim 1.

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