KR102446721B1 - Method for manufacturing high voltage multi-layer ceramic capacitor - Google Patents

Abstract

The present invention relates to a method for manufacturing a high-voltage multilayer ceramic capacitor, wherein a plurality of green sheets in which a plurality of stripe pattern electrodes are formed to be spaced apart from each other are stacked so that the stripe pattern electrodes cross each other, and then pressed to form a compression bar to do; forming a cut bar by cutting the compression bar so that the stripe pattern-type electrode is formed as an internal electrode having an overall electrode shape on the side surface in which the end of one side or the other side is exposed in the width direction; forming a fired bar by sintering the cutting bar after binder degreasing; forming a side insulating layer on one side or the other side of the firing bar in the width direction using an aerosol coating method, respectively; forming a fired chip by cutting the firing bar on which the side insulating layer is formed so that the inner electrode having the entire side electrode shape is exposed at one end or the other end in the longitudinal direction; and forming an external electrode at one end or the other end of the firing chip in the longitudinal direction to be connected to the internal electrode, respectively.

Description

Method for manufacturing high voltage multi-layer ceramic capacitor

The present invention relates to a method for manufacturing a high-voltage multilayer ceramic capacitor, and in particular, after forming a firing bar by sintering a cut bar having internal electrodes in the shape of an entire side electrode, one or the other side in the width direction of the firing bar is made of the same dielectric material as the firing bar. By applying an aerosol coating method to form a side insulating layer, the internal electrode formed in the shape of the entire side electrode exposed to the interface of one or the other end in the width direction of the firing bar is insulated to improve reliability and productivity of manufacturing work when applied to high voltage. It relates to a method for manufacturing a multilayer ceramic capacitor that can be improved.

A multilayer ceramic capacitor (MLCC) is manufactured by alternately stacking dielectric layers and internal electrode layers, and a related technology is disclosed in Korean Patent Registration No. 10-1731452 (Patent Document 1).

Patent Document 1 discloses a high voltage multilayer ceramic capacitor, which includes a multilayer ceramic sintered body, a plurality of first internal electrode layers, a plurality of second internal electrode layers, a first external electrode, a second external electrode, and a first arc shield pattern. and a plurality of second arc shield pattern layers. The multilayer ceramic sintered body of the multilayer ceramic capacitor has a plurality of first internal electrode layers or a plurality of second internal electrode layers formed therein, and the plurality of first internal electrode layers are disposed inside the multilayer ceramic sintered body on one side in the first direction, respectively. The ends of the multilayer ceramic sintered body are respectively exposed to the ends of one side in the first direction, and the plurality of second internal electrode layers each have the other end of the multilayer ceramic sintered body inside the multilayer ceramic sintered body in the first direction. They are respectively exposed to the ends of the other side in one direction and are formed so as to alternately cross each other with the plurality of first internal electrode layers. The first external electrode is formed to surround one end of one side of the multilayer ceramic sintered body in the first direction so as to be respectively connected to the plurality of first internal electrode layers, and the second external electrode is stacked to be connected to the plurality of second internal electrode layers, respectively. It is formed to surround the other end of the ceramic sintered body in the first direction. The first arc shield pattern layer is disposed on the same plane as the plurality of first internal electrode layers, is spaced apart from the first internal electrode layer, and is formed inside the plurality of laminated ceramic sintered bodies to surround the first internal electrode layer, and the plurality of second internal electrode layers The arc shield pattern layers are respectively disposed on the same plane as the plurality of second internal electrode layers and are spaced apart from the second internal electrode layers and formed inside the multilayer ceramic sintered body to surround the second internal electrode layers.

In the multilayer ceramic capacitor as described in Patent Document 1, an internal electrode is formed in a side full pattern shape electrode to be used for high voltage. In a conventional method of manufacturing a multilayer ceramic capacitor for high voltage having internal electrodes formed in the shape of all side electrodes, the internal electrodes having the shape of all side electrodes are printed on the sheet after the sheet is formed. When the internal electrode is printed, a plurality of sheets are stacked and compressed to form a compression bar. The compression bar is cut to form a cutting bar to expose the inner electrode having an overall electrode shape on the side, and when the cut bar is formed, a side insulating layer is formed to insulate the side, that is, the cut bar and the inner electrode exposed in the width direction. The cutting bar on which the side insulating layer is formed is cut again to form green chips, and when the green chips are formed, known processes such as binder degreasing, sintering, reoxidation heat treatment, polishing, external electrode formation and plating are performed to perform conventional high-pressure processes. for the manufacture of multilayer ceramic capacitors.

As described above for the conventional high-voltage multilayer ceramic capacitor in which the inner electrode is formed in the shape of an entire side electrode, a dipping or printing method is used to insulate the inner electrode exposed through the end of one or the other side in the width direction of the cutting bar. There is a problem that the productivity of the manufacturing process may be reduced due to the need to repeat several times by forming the side insulating layer as a side insulating layer. ) may occur, and when the side insulating layer is formed using a dielectric material different from the dielectric material of the cutting bar in order to equalize the shrinkage rate, the inner electrode is formed in the shape of the entire side electrode in the width direction of one side or the other side of the cutting bar. There is a problem in that deformation that is bent in the vertical direction at the interface may occur.

: Korea Patent Publication No. 10-1731452

An object of the present invention is to solve the above problems, and after forming a firing bar by sintering a cutting bar having an internal electrode in the shape of an entire side electrode, the same dielectric material as the firing bar is formed on one side or the other side in the width direction of the firing bar. By applying an aerosol coating method to form a side insulating layer, the internal electrode formed in the shape of the entire side electrode exposed to the interface of one or the other end in the width direction of the firing bar is insulated to improve reliability and productivity of manufacturing work when applied to high voltage. An object of the present invention is to provide a method for manufacturing a high-voltage multilayer ceramic capacitor that can be improved.

Another object of the present invention is to form a firing bar by sintering a cutting bar having an internal electrode in the shape of an entire side electrode, and then apply the same dielectric material as the firing bar to one or the other side in the width direction of the firing bar by an aerosol coating method to insulate the side. By forming a layer, the occurrence of cracks due to simultaneous sintering of the cutting bar and the side insulating layer is prevented, or the internal electrode formed in the shape of the entire side electrode is bent in the vertical direction at the interface of one side or the other side in the width direction of the cutting bar. An object of the present invention is to provide a method for manufacturing a high-voltage multilayer ceramic capacitor capable of preventing side steps of a firing bar.

According to the method of manufacturing a high-voltage multilayer ceramic capacitor of the present invention, a plurality of green sheets in which a plurality of stripe pattern-shaped electrodes are formed to be spaced apart from each other at regular intervals are stacked so that the stripe pattern-shaped electrodes cross each other. and then pressing to form a pressing bar; forming a cut bar by cutting the compression bar so that the stripe pattern-type electrode is formed as an internal electrode having a side full pattern shape electrode in which one end or the other end is exposed in the width direction; forming a fired bar by sintering the cutting bar after binder degreasing; forming a side insulating layer on one side or the other side in the width direction of the firing bar using an aerosol coating method, respectively; forming a fired chip by cutting the firing bar on which the side insulating layer is formed so that one or the other end of the inner electrode having an overall side electrode shape is exposed in the longitudinal direction; and forming an external electrode at one end or the other end of the fired chip in the longitudinal direction to be connected to the internal electrode, respectively.

In the method for manufacturing a high-voltage multilayer ceramic capacitor of the present invention, a firing bar is formed by sintering a cutting bar with internal electrodes formed in the shape of an entire side electrode, and then the same dielectric material as the firing bar is applied to one side or the other side in the width direction of the firing bar by an aerosol coating method. By applying the coating to form a side insulating layer, the internal electrode formed in the shape of an entire side electrode exposed to the interface of one end or the other end in the width direction of the firing bar is insulated to improve reliability and productivity of manufacturing work when applied to high voltage. There is an advantage, and it prevents the occurrence of cracks due to simultaneous sintering of the cutting bar and the side insulating layer, or by eliminating the occurrence of deformation in which the internal electrode formed in the shape of the entire side electrode is bent in the vertical direction at the interface of one side or the other side in the width direction of the cutting bar. There is an advantage in that the side step difference of the firing bar can be prevented.

1 is a process flow diagram of a method for manufacturing a high-voltage multilayer ceramic capacitor according to the present invention;
2 is a perspective view of a green sheet having a plurality of stripe pattern-type electrodes manufactured by using the method of forming a compression bar shown in FIG. 1;
3 is a perspective view of a stacking bar showing a state in which a plurality of green sheets shown in FIG. 2 are stacked;
4 is a front view showing one side of the laminated bar shown in FIG. 3 in the longitudinal direction;
5 is a side cross-sectional view taken along line AA of the laminated bar shown in FIG. 3;
6 is a side cross-sectional view taken along line AA in a state in which the laminated bar shown in FIG. 3 is pressed;
7 is a perspective view of a cutting bar formed by cutting the pressing bar shown in FIG. 6;
8 is a perspective view of a fired bar in which a side insulating layer is formed after firing the cutting bar shown in FIG. 7;
9 is a perspective view of a fired chip formed by cutting the firing bar shown in FIG. 8;
10 is a cross-sectional view showing a state in which external electrodes are formed on the fired chip shown in FIG. 9;
11 is a schematic configuration diagram of an aerosol application device for forming the side insulating layer shown in FIG.

Hereinafter, an embodiment of a method for manufacturing a high-voltage multilayer ceramic capacitor of the present invention will be described with reference to the accompanying drawings.

1, 2, 6, 8, and 9, in the method of manufacturing a high-voltage multilayer ceramic capacitor of the present invention, a plurality of stripe pattern shape electrodes 111 are spaced apart from each other at regular intervals, respectively. A step (S10) of forming a compression bar 130 by stacking a plurality of green sheets 110 to be formed so that the stripe pattern-type electrodes 111 intersect each other and then pressing is performed. When the compression bar 130 is formed, the stripe pattern electrode 111 is formed as an internal electrode 112 having a side full pattern shape electrode in which the end of one side or the other side is exposed in the width direction (Y). A step (S20) of cutting the pressing bar 130 to form a cutting bar 140 is performed. When the cutting bar 140 is formed, the binder is degreasing the cutting bar 140 and then sintering to form the fired bar 150 ( S30 ) is performed. When the firing bar 150 is formed, the step (S40) of forming the side insulating layer 113 on one side or the other side of the firing bar 150 in the width direction Y by using an aerosol coating method, respectively, is performed. When the side insulating layer 113 is formed, the firing bar 150 on which the side insulating layer 113 is formed is cut so that the inner electrode 112 having the entire side electrode shape is exposed at one end or the other end in the longitudinal direction (X). A step (S50) of forming the fired chip 160 is performed. When the fired chip 160 is formed, the step (S60) of forming an external electrode 114 to be connected to the internal electrode 112 at one or the other end of the fired chip 160 in the longitudinal direction (X) is performed. A high-voltage multilayer ceramic capacitor of the present invention is manufactured.

Specific examples of each step in the method for manufacturing a high-voltage multilayer ceramic capacitor of the present invention will be described as follows.

In the step (S10) of forming the compression bar 130, a plurality of greens using a doctor blade method after slurrying by adding PVB (Polyvinyl Butyral) used as an organic binder to a dielectric material as shown in FIGS. 1 to 6 . A step (S11) of forming the sheet 110 is performed. When the plurality of green sheets 110 are formed, each electrode material paste is printed on the plurality of green sheets 110 by a screen printing method to form a plurality of stripe pattern-type electrodes 111 spaced apart from each other at regular intervals. step (S12) is performed. When the stripe pattern-type electrode 111 is formed, a step (S13) of stacking a plurality of green sheets 110 so that the stripe pattern-type electrode 111 intersects each other in the longitudinal direction (X) to form the stacked bar 120 is performed (S13). carry out When the laminated bar 120 is formed, the step (S14) of forming the pressing bar 130 by pressing the laminated bar 120 at 800 to 1300 kgf/cm 2 is performed.

In the step (S11) of manufacturing the plurality of green sheets 110 during the step (S10) of forming the compression bar 130, the dielectric material is formed by mixing calcined powder and rare earth glass frit, and calcined. The powder is formed by mixing and pulverizing BaTiO ₃ powder and additive powder and then calcining at 600 to 1200 ° C. The additive powder is MgO, Mn ₃ O ₄ , Cr ₂ O ₃ , Al ₂ O ₃ , CaCO ₃ , ZrO ₂ , Seven or more of Y ₂ O ₃ , Dy ₂ O ₃ and Yb ₂ O ₃ are selected and used. Here, the rare-earth glass frit is formed by adding a rare-earth oxide to the glass frit, and BaO, CaO, and SiO ₂ are used as the glass frit, and the rare-earth oxide is Y ₂ O ₃ , Dy ₂ O ₃ , and two of Yb ₂ O ₃ . The above is selected and used.

In the step (S12) of forming the plurality of stripe pattern-type electrodes 111, the electrode material paste is formed by mixing nickel (Ni) powder, a binder, a dispersant, and an organic solvent. Here, ethyl cellulose is used as a binder, glycerol-alpha-monooleate is used as a dispersant, and terpineol is used as an organic solvent.

In the step (S13) of forming the lamination bar 120, the lamination bar 120 is prepared by preparing a plurality of green sheets 110 on which the stripe pattern electrode 111 shown in FIG. 2 is formed, and then the plurality of green sheets 110 ) is prepared, as in FIGS. 3 and 4 , the green sheet 110 is disposed to cross each other by the width length of one stripe pattern type electrode 111 so that the stripe pattern type electrode 111 moves in the longitudinal direction (X). A plurality of green sheets 110 are stacked to cross each other to form a stacked bar 120 .

In the step (S14) of forming the pressing bar 130, the pressing bar 120 forms a cover sheet 116 on the upper and lower portions of the laminated bar 120, respectively, when the laminated bar 120 is formed as shown in FIG. After that, a pressure of 800 to 1300 kgf/cm 2 is applied to the lamination bar 120 through the cover sheet 116 to form it.

In the step (S20) of forming the cutting bar 140, as in FIGS. 1 and 7, when the pressing bar 130 is formed, the pressing bar 130 is cut along the cutting line CL1 shown in FIG. The cutting bar 140 is formed so that the pattern-type electrode 111 is formed as an internal electrode 112 having an overall electrode shape on the side in which the end of one side or the other side is exposed in the width direction (Y). That is, the cutting bar 140 cuts the cutting line CL1 set along the longitudinal direction X of the compression bar 130 as shown in FIG. It is formed to have the shape of the entire side electrode where the tip is exposed.

Forming the firing bar 150 (S30), as shown in Figs. 1 and 8, the internal electrode 112 in the width direction (Y) is cut so that the ends of one side and the other side are exposed, the cutting bar 140 is 200 To remove the binder by degreasing at 800 °C (S31) is performed. When binder degreasing is completed, the step (S32) of forming the fired bar 150 by sintering the binder-degreasing cut bar 140 in a reducing atmosphere at 1260 to 1360° C. is performed. When the firing bar 150 is formed, a step (S33) of oxidizing the firing bar 150 on which the sintering is completed at 800 to 1000°C is performed.

In the step (S40) of forming the side insulating layer 113 using the aerosol coating method, as in FIGS. 1 and 8 , the inner electrode 112 having the entire side electrode shape is formed at one side or the other end in the width direction (Y). A step (S41) of surface-treating the firing bar 150 to be exposed is performed. In the step (S41) of surface-treating the firing bar 150, the firing bar 150 is barrel polished so that the inner electrode 112 having the entire side electrode shape is exposed at one end or the other end in the width direction (Y). plasma treatment.

When the surface treatment of the firing bar 150 is completed, the width of the firing bar 150 on which the surface treatment is completed so that the inner electrode 112 having the entire side electrode shape is exposed in the width direction Y or the end of the other side is covered. A step (S42) of forming a side insulating layer using an aerosol coating method on one side or the other side of the direction (Y) is performed. In the step of forming the side insulating layer ( S42 ), the side insulating layer 113 is made of the same dielectric material as that of the green sheet 110 , and has a thickness Th of 25 to 200 μm, and the side insulating layer As a dielectric material used to form 113, powder is used, and the powder has an average particle diameter of 0.05 to 1 μm. In this way, by forming the side insulating layer 113 using the aerosol coating method, it has a heat treatment effect with impact energy due to the irradiation speed of the dielectric material powder, so that it has excellent crystallinity and has a thickness (Th) of 25 to 200 μm. It becomes possible to form a thick film at once without a sintering process. When the size of the dielectric material powder is 0.05 μm or less, there is a problem that the time to form the side insulating layer 113 is long, and when it is 1 μm or more, the nozzle 13a of the aerosol coating device (10: shown in FIG. 11): 11) is clogged or the surface is rough.

In the step of forming the side insulating layer (S42), the dielectric material used to form the side insulating layer is formed by mixing calcined powder and rare earth glass frit, and the calcined powder is BaTiO ₃ powder and additive powder. It is formed by mixing and pulverizing and calcining at 600 to 1200° C., and the additive powder is MgO, Mn ₃ O ₄ , Cr ₂ O ₃ , Al ₂ O ₃ , CaCO ₃ , ZrO ₂ , Y ₂ O ₃ , Dy ₂ O At least seven of ₃ and Yb ₂ O ₃ are selected and used, the rare earth glass frit is formed by adding a rare earth oxide to the glass frit, BaO, CaO and SiO ₂ are used for the glass frit, and the rare earth oxide is Y ₂ O ₃ , Dy ₂ O ₃ and Yb ₂ O ₃ At least two are selected and used.

In the step (S50) of forming the fired chip 160, as shown in FIGS. 1 and 9, the firing bar 150 on which the side insulating layer 113 is formed is cut so that the internal electrode 112 having the entire side electrode shape has a length. The fired chip 160 is formed by cutting using a diamond saw (not shown) so that the end of one side or the other side is exposed in the direction X, and the firing chip 160 forming step S51 is performed. When the fired chip 160 is formed, a step (S52) of re-oxidizing the fired chip 160 at 800 to 1000°C is performed. When the re-oxidation treatment is completed, a step (S53) of barrel polishing the calcined chip 160 on which the re-oxidation heat treatment has been completed is exposed at one end or the other end in the longitudinal direction (X) of the inner electrode 112 having the entire side electrode shape (S53). carry out

In the step S51 of forming the sintered chip 160, the sintered chip 160 cuts the sintered bar 150 along the cutting line CL2 shown in FIG. 8 using a diamond saw or a laser cutting device (not shown). Thus, the inner electrode 112 is formed to expose the tip of one side or the other side in the longitudinal direction (X) of the fired chip 160 . As shown in FIG. 9 , the internal electrodes 112 of the fired chip 160 are exposed at one side and the other end in the longitudinal direction X of the fired chip 160 , and one side in the width direction Y of the fired chip 160 . It is formed to have an overall electrode shape on the side exposed to the end and the other end, respectively.

The step of forming the external electrode 114 to be connected to the internal electrode 112 ( S60 ) is, as shown in FIGS. 1 and 10 , the internal electrode at one or the other end of the calcined chip 160 in the longitudinal direction X, respectively. After forming the external electrode 114 that is formed to be connected to the 112, a heat treatment step (S61) is performed at 600 to 700°C. When the external electrode 114 is formed, the step of forming the plating layer 115 on the surface of the external electrode 114 ( S62 ) is performed. Here, the material of the external electrode 114 is nickel (Ni) or copper (Cu) is used, and the material of the plating layer is a mixture of one or more of tin (Sn), zinc (Zn), and aluminum (Al). used

The aerosol coating method used in the step (S40) of forming the side insulating layer 113 using the aerosol coating method above is applied using the aerosol coating device 10 as in FIG. 11, and the aerosol coating device 10 is It schematically consists of a carrier gas chamber 11 , an aerosol chamber 12 and a deposition chamber 13 . In the carrier gas chamber 11 , when a carrier gas such as oxygen (O ₂ ) is injected, the injection flow rate is 10 to 40 L (liter) per minute, and the dielectric ceramic introduced into the aerosol chamber 12 connected to the carrier gas chamber 11 . The composition powder is injected into the deposition chamber 13 . In the deposition chamber 13, when the ceramic firing bar 150 is mounted on the jig 13b while maintaining the vacuum state by the vacuum pump 13c, the dielectric ceramic introduced into the aerosol chamber 12 through the nozzle 13a. By irradiating the composition powder, the side insulating layer 13 is formed on the ceramic firing bar 150 . When the side insulating layer 13 is formed on one side of the ceramic firing bar 150, the mounting position is adjusted in the jig 13b to form the side insulating layer 13 on the other side.

Comparative Examples and Examples 1 to 16 were respectively prepared as shown in Table 1 to test the electrical characteristics of the high voltage multilayer ceramic capacitor manufactured according to the method of manufacturing the high voltage multilayer ceramic capacitor of the present invention.

The high-voltage multilayer ceramic capacitor according to the comparative example includes a green sheet (not shown) and BaTiO ₃ as a main component, yttrium oxide (Y ₂ O ₃ ), magnesium oxide (MgO), manganese oxide (Mn ₃ O ₄ ), silicon oxide (SiO ₂ ) ) and glass frit, etc. were added and manufactured to have a thickness of 7 μm, and when the green sheet was manufactured, the metal material paste used for the internal electrode was applied to the green sheet using screen printing to form the internal electrode. prepared. A plurality of green sheets with internal electrodes were prepared, and 190 of the plurality of green sheets were laminated to manufacture a 190-layer lamination bar (not shown). Then, it was cut into green chips (not shown) having a size of '3216'. The cut green chips were first calcined at 250° C. for 45 hours in air, and then secondary calcination was performed at 850° C. for 4 hours in an inert gas atmosphere. For the primary and secondary calcination, the grip chip was heated to 80 °C/min in a reducing atmosphere and sintered at 1200 °C for ₂ hours. did. After the oxidation treatment is completed, both ends of the inner electrode are exposed by barrel polishing, and after coating using copper (Cu), heat treatment at 700° C. ) was prepared by forming a multilayer capacitor (not shown) according to a comparative example having a size of 3216 (3.2 mm × 1.6 mm × 1.6 mm).

The multilayer ceramic capacitors according to Examples 1 to 16 according to the present invention each used the same green sheet 110, and the green sheet 110 contains BaTiO ₃ as a main component, yttrium oxide (Y ₂ O ₃ ), and magnesium oxide. (MgO), manganese oxide (Mn ₃ O ₄ ), silicon oxide (SiO ₂ ), and glass frit were added and prepared to have a thickness of 7 μm. A plurality of stripe pattern-type electrodes 111 formed on the surface of the green sheet 110 to be in contact with each other in the width direction (Y) and spaced apart from each other at regular intervals in the longitudinal direction (X) as in FIG. 2 are used for internal electrodes. The metal paste to be used was prepared by using screen printing (Screen Printing). A plurality of green sheets 110 on which a plurality of stripe pattern-type electrodes 111 are formed were prepared, and 150 of the plurality of green sheets 110 were stacked as shown in FIGS. 2 and 4 to manufacture a stacked bar 120 . did. The lamination bar 120 is obtained by laminating the green sheet 110 in 150 layers. When the lamination bar 120 is formed, the lamination bar 120 is formed in a state in which the cover sheet 16 is formed on the lamination bar 120 as shown in FIG. 6 . (120) was compressed at 1000 kgf/cm 2 to prepare a compression bar 130 . When the pressing bar 130 is manufactured, the pressing bar 130 is cut along the cutting line CL1 shown in FIG. 3 to have a width of 3.2 mm and a length of 100 to 300 mm, and the cutting bar 140 as in FIG. 6 . was prepared. When the cutting bar 140 was manufactured, the cutting bar 140 was first calcined at 250° C. in air for 45 hours, and then secondary calcination was performed at 850° C. for 4 hours in an inert gas atmosphere. After performing the primary and secondary calcination, the cutting bar 140 was heated at 80° C./min in a reducing atmosphere and sintered at 1200° C. for 2 hours to form the fired bar 150 . When the firing bar 150 was formed, oxidation treatment was performed on the firing bar 150 at 1000° C. in an oxygen (O ₂ ) atmosphere of 35 ppm. When the oxidation treatment is completed, the side insulating layer 13 is formed to have a thickness Th of 10 to 100 μm using the firing bar 150 as an aerosol coating method, and then the firing bar 150 is fired using a diamond saw. The bar 150 was cut to fit the size of '3216' to form a fired chip 160 as shown in FIG. 9 . After the firing chip 160 is formed, barrel polishing is performed, the ends of one side and the other side of the internal electrode 112 are exposed, and then copper (Cu) is coated on one side and the other side of the fired chip 160, respectively. An external electrode 114 connected to the internal electrode 12 was formed by heat treatment at ℃ as shown in FIG. 10, and then tin (Sn) was applied to the surface of the external electrode 114 to form a plating layer 115, A multilayer capacitor having a size of 3216' (3.2 mm × 1.6 mm × 1.6 mm) was manufactured.

The difference between the multilayer ceramic capacitors according to Examples 1 to 16 according to the present invention is that the thickness Th of the side insulating layer 13 and the average particle diameter of the dielectric material powder for forming the side insulating layer 13 are different. was prepared. In Example 1, the size of the powder, that is, the average particle diameter was 5 μm or more, and the thickness (Th) was 250 μm, and Examples 2 to 16 set the size and thickness (Th) of the powder as in Table 1, respectively. prepared.

product powder size
(μm) Thickness (Th)
(μm) electrical properties Life characteristics Insulation breakdown voltage per unit thickness (V/㎛) static capacity
(㎌) dielectric loss
(%) Insulation Resistance
(GΩ) MTTF
(hr) comparative example doesn't exist doesn't exist 4.8 5.2 1.62 108 63 Example 1 doesn't exist 0 Short defect occurrence Example 2 0.05 5 5.25 4.87 8.24 192 85 Example 3 0.5 5 5.22 4.88 7.24 170 86 Example 4 1.0 5 5.22 4.88 8.20 152 85 Example 5 0.05 10 5.25 4.91 8.25 210 88 Example 6 0.5 10 5.23 4.91 9.12 210 87 Example 7 1.0 10 5.25 4.9 9.13 200 88 Example 8 0.05 100 5.23 4.87 8.94 225 92 Example 9 0.5 100 5.25 4.77 8.24 210 90 Example 10 1.0 100 5.25 4.77 9.12 198 91 Example 11 0.05 150 5.23 4.87 8.24 250 91 Example 12 0.5 150 5.28 4.92 9.10 233 91 Example 13 1.0 150 5.24 4.92 8.80 200 91 Example 14 0.05 200 5.22 4.87 8.50 248 90.5 Example 15 0.5 200 5.22 4.87 9.21 245 91 Example 16 1.0 200 5.25 4.92 8.21 223 92

As a result of measuring the electrical characteristics of the multilayer ceramic capacitors according to Comparative Examples and Examples 1 to 16, as shown in Table 1, the Comparative Example had a capacitance of 4.8 μF, a dielectric loss of 5.2%, and an insulation resistance of 1.62 GΩ. , MTTF (mean time between failure) of 108 hr and breakdown voltage per unit thickness of 63V/㎛ were measured. On the other hand, in Example 1, the size of the powder, that is, the average particle diameter was 5 μm or more, and the thickness Th was 250 μm, but the application energy increased due to the large average particle diameter of the powder. It is determined that a short circuit in which the internal electrodes 112 are connected to each other due to the impact is applied. In Examples 2 to 16, respectively, the capacitance, dielectric loss, insulation resistance, MTTF (mean time between failure), and breakdown voltage per unit thickness were improved compared to Comparative Examples. In particular, in Examples 2 to 16, it can be seen that the MTTF (mean time between failure) and the breakdown voltage per unit thickness are particularly improved as in Table 1 compared to the comparative example, respectively, which is a side insulating layer ( 13) was judged to be due to the formation of Capacitance (㎌) and dielectric loss (%) during the electrical property test according to Comparative Examples and Examples 1 to 16 were measured using a capacity measuring instrument (3504-50C HiTester, HIOKI), 1 kHz, voltage 0.5 Vrms, The capacitance at 25°C was measured. Insulation resistance (GΩ) was measured using a high resistance meter (High Resistance Meter 4329A, HP Co.), and was measured by applying a DC voltage of 10 to 50V at 25°C for 60 seconds. In the high-temperature load test, a high-temperature load test was performed under the conditions of 150° C. and 100 V for Comparative Examples and Examples 1 to 16 in which the capacitance was measured, and the time when the insulation resistance became 10 KΩ or less was determined as a failure, and this failure The MTTF (mean time to failure) was calculated from the time. The breakdown voltage per unit thickness was applied at a rate of 5V/min at 25°C, and the breakdown voltage was measured when the leakage current was 100 mA using a withstand voltage measuring device.

As described above, in the method for manufacturing a high-voltage multilayer ceramic capacitor of the present invention, a firing bar is formed by sintering a cut bar having internal electrodes formed in the shape of an entire side electrode, and then the same dielectric material as that of the firing bar is applied to one side or the other side in the width direction of the firing bar. By applying an aerosol coating method to form a side insulating layer, the internal electrode formed in the shape of the entire side electrode exposed to the interface of one or the other end in the width direction of the firing bar is insulated to improve reliability and productivity of manufacturing work when applied to high voltage. can be improved

The high-voltage multilayer ceramic capacitor manufacturing method of the present invention is applied to the manufacturing industry of multilayer components.

110: green sheet 111: stripe pattern electrode
112: inner electrode 113: side insulating layer
114: external electrode 115: plating layer
116: cover sheet 120: laminated bar
130: compression bar 140: cutting bar
150: firing bar 160: firing chip

Claims (9)

forming a compression bar by stacking a plurality of green sheets in which a plurality of stripe pattern shape electrodes are respectively formed to be spaced apart from each other at regular intervals so that the stripe pattern shape electrodes intersect with each other and then pressing;
forming a cut bar by cutting the compression bar so that the stripe pattern-type electrode is formed as an internal electrode having a side full pattern shape electrode in which one end or the other end is exposed in the width direction;
forming a fired bar by sintering the cutting bar after binder degreasing;
forming a side insulating layer on one side or the other side in the width direction of the firing bar using an aerosol coating method, respectively;
forming a fired chip by cutting the firing bar on which the side insulating layer is formed so that one or the other end of the inner electrode having an overall side electrode shape is exposed in the longitudinal direction; and
forming an external electrode at one end or the other end of the fired chip in the longitudinal direction to be connected to the internal electrode, respectively;
The forming of the side insulating layer using the aerosol coating method includes: surface-treating the firing bar so that the inner electrode having the entire side electrode shape is exposed at one end or the other end in the width direction; and an aerosol coating method on one side or the other side of the firing bar in the width direction where the surface treatment is completed so that the end of one side or the other side exposed in the width direction of the inner electrode having the entire side electrode shape is covered. In the forming of the side insulating layer, the side insulating layer is made of the same dielectric material as the dielectric material forming the green sheet and has a thickness of 25 to 200 μm, and the side insulating layer is formed of A method of manufacturing a high-voltage multilayer ceramic capacitor, wherein the dielectric material used for forming the dielectric material is powder, and the powder has an average particle diameter of 0.05 to 1 μm. According to claim 1,
The forming of the compression bar may include: forming a plurality of green sheets using a doctor blade method after slurrying a dielectric material by adding PVB (Polyvinyl Butyral) used as an organic binder;
forming a plurality of stripe pattern-type electrodes spaced apart from each other at regular intervals by printing an electrode material paste on the plurality of green sheets by a screen printing method;
forming a stacked bar by stacking the plurality of green sheets so that the stripe pattern-type electrodes cross each other in a longitudinal direction; and
and pressing the laminated bar at 800 to 1300 kgf/cm 2 to form a pressing bar. 3. The method of claim 2,
In the step of manufacturing the plurality of green sheets, the dielectric material is formed by mixing calcined powder and rare earth glass frit, and the calcined powder is mixed with BaTiO ₃ powder and additive powder and pulverized and then pulverized to 600 to It is formed by calcining at 1200° C., and the additive powder is MgO, Mn ₃ O ₄ , Cr ₂ O ₃ , Al ₂ O ₃ , CaCO ₃ , ZrO ₂ , Y ₂ O ₃ , Dy ₂ O ₃ and Yb ₂ O ₃ . Seven or more are selected and used, the rare earth glass frit is formed by adding a rare earth oxide to the glass frit, BaO, CaO and SiO ₂ are used as the glass frit, and the rare earth oxide is Y ₂ O ₃ , Dy ₂ O ₃ and Yb ₂ O ₃ A method of manufacturing a high-voltage multilayer ceramic capacitor in which two or more are selected and used. 3. The method of claim 2,
In the step of forming the plurality of stripe pattern-type electrodes, the electrode material paste is formed by mixing nickel (Ni) powder, a binder, a dispersing agent and an organic solvent, and the binder is ethyl cellulose. A method of manufacturing a high-pressure multilayer ceramic capacitor, wherein glycerol-alpha-monooleate is used as the dispersant and terpineol is used as the organic solvent. According to claim 1,
The forming of the firing bar may include removing the binder by degreasing the cutting bar at 200 to 800° C. in which the inner electrode is cut so that the ends of one side and the other side are exposed in the width direction;
sintering the cut bar from which the binder is degreased in a reducing atmosphere at 1260 to 1360° C. to form a calcined bar; and
and oxidizing the sintered bar at 800 to 1000°C. delete According to claim 1,
In the step of surface-treating the firing bar and the step of forming the side insulating layer, the step of surface-treating the firing bar is barrel polishing the firing bar so that one or the other end of the inner electrode having an overall side electrode shape is exposed in the width direction. or plasma treatment,
In the step of forming the side insulating layer, the dielectric material used to form the side insulating layer is formed by mixing calcined powder and rare earth glass frit, and the calcined powder is BaTiO ₃ powder and additive powder. It is formed by mixing and pulverizing and calcining at 600 to 1200° C., and the additive powder is MgO, Mn ₃ O ₄ , Cr ₂ O ₃ , Al ₂ O ₃ , CaCO ₃ , ZrO ₂ , Y ₂ O ₃ , Dy ₂ O At least seven of ₃ and Yb ₂ O ₃ are selected and used, the rare earth glass frit is formed by adding a rare earth oxide to the glass frit, and the glass frit includes BaO, CaO and SiO ₂ , and the rare earth oxide is Y ₂ O ₃ , Dy ₂ O ₃ and Yb ₂ O ₃ A method of manufacturing a high-voltage multilayer ceramic capacitor in which two or more are selected and used. According to claim 1,
In the forming of the fired chip, the firing bar on which the side insulating layer is formed is cut so that the inner electrode having the entire side electrode shape is exposed at one end or the other end in the longitudinal direction using a diamond saw to cut the fired chip. forming step;
re-oxidizing the fired chips at 800 to 1000°C; and
and barrel-polishing the fired chip on which the reoxidation heat treatment has been completed to expose one end or the other end in the longitudinal direction of the inner electrode having the entire side electrode shape. According to claim 1,
The step of forming the external electrode to be connected to the internal electrode may include: forming external electrodes connected to the internal electrodes at one end or the other end in the longitudinal direction of the fired chip, respectively, and then performing heat treatment at 600 to 700°C; and
Forming a plating layer on the surface of the external electrode,
Nickel (Ni) or copper (Cu) is used as the material of the external electrode, and the material of the plating layer is high pressure using one or a mixture of one or more of tin (Sn), zinc (Zn), and aluminum (Al). A method for manufacturing a multilayer ceramic capacitor.

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