JP2691715B2 - Ferrite sintered body, chip inductor and LC composite parts - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ferrite sintered body used as various magnetic materials, a chip inductor using this sintered body as a magnetic material, and a capacitor section and an inductor section in one chip. With LC composite parts. 2. Prior Art and its Problems Various ferrites are used as various magnetic core materials because of their excellent magnetic properties. And especially Ni
Ni-based ferrites such as ferrites, Ni-Zn ferrites, and Ni-Cu-Zn ferrites have been widely used as materials for low-temperature sintering such as printing methods and green sheet methods. However, the ferrite sintered body is not satisfactory in terms of mechanical strength. Further, in order to increase the sintering density and increase the mechanical strength, it is necessary to increase the sintering temperature, which causes a problem that the production cost is increased. On the other hand, ferrite is made into a paste, an internal conductor is formed inside by a printing method or a green sheet method, and then sintered to be used as a chip inductor or an LC composite component having an inductor part and a capacitor part in one chip. . Even in such a case, there are serious problems in that the mechanical strength is low and the sintering temperature must be increased. Further, in these inductors, the frequency characteristics of the inductance and the Q value are insufficient, and the inductance and the Q value become substantially zero in the high frequency band exceeding 200 KHz, for example. In order to improve the frequency characteristics, a non-magnetic ceramic may be used for the inductor section to form an air-core coil, but this one has only insufficient characteristics in terms of inductance and Q value. In addition, in LC composite parts that have an inductor part and a capacitor part on one chip, peeling of the LC interface, warpage, etc., may occur during sintering due to the difference in shrinkage ratio between the ferrite part of the inductor part and the dielectric material of the capacitor part. However, there is a problem that cracks occur due to the difference in the coefficient of linear expansion and the function as a surface mount component cannot be satisfied. The ferrite sintered body is used for various magnetic cores, magnetic shield materials, radio wave shield materials, attenuators, etc., but also in these applications, improvement of the sintering temperature, sintering density, mechanical strength, etc., It is desired to improve frequency characteristics of electromagnetic characteristics such as permeability loss. II Object of the invention The object of the present invention is that the mechanical strength is high compared to the conventional one,
An object of the present invention is to provide a ferrite sintered body which can lower the sintering temperature and has good high-frequency characteristics, a chip inductor, and an LC composite component which does not warp or peel even when co-firing. III Disclosure of the Invention Such an object is achieved by the present invention described below. That is, the present invention contains ferrite and borosilicate glass, the content of borosilicate glass is 15 to 75 wt%, borosilicate glass is 65 to 90 wt% silicon oxide and 8 ~
A ferrite sintered body characterized by containing 30 wt% of boron oxide. The second invention contains ferrite, borosilicate glass, and boron oxide, the content of borosilicate glass is 15 to 75 wt%, and the content of borosilicate glass is 65 to 90 wt% silicon oxide and 8 to 30%.
The ferrite sintered body is characterized by containing wt% of boron oxide. A third invention is a chip inductor in which a ceramic magnetic layer and an internal conductor layer are laminated, wherein the ceramic magnetic layer contains ferrite and borosilicate glass, and the content of borosilicate glass is 15 to 75 wt%. , Borosilicate glass contains 65 ~ 90wt% silicon oxide and 8 ~
A chip inductor characterized by containing 30 wt% of boron oxide. A fourth invention is a chip inductor in which a ceramic magnetic layer and an internal conductor layer are laminated, wherein the ceramic magnetic layer contains ferrite, borosilicate glass and boron oxide, and the borosilicate glass content is 15 to 75 wt. % Of borosilicate glass is 65 to 90 wt% silicon oxide and 8 to
A chip inductor characterized by containing 30 wt% of boron oxide. A fifth aspect of the present invention is a ceramic LC composite component in which a capacitor section in which a ceramic dielectric layer and an electrode layer are laminated, and an inductor section in which a ferrite magnetic layer and an internal conductor layer are laminated are integrated. Contains ferrite and borosilicate glass, the content of borosilicate glass is 15 to 75 wt%, borosilicate glass is 75 to 90 wt% silicon oxide and 8 ~
It is an LC composite part characterized by containing 20 wt% of boron oxide. A sixth aspect of the present invention is a ceramic LC composite component in which a capacitor part in which a ceramic dielectric layer and an electrode layer are laminated, and an inductor part in which a ceramic magnetic layer and an internal conductor layer are laminated are integrated. Contains ferrite, borosilicate glass and boron oxide, the content of borosilicate glass is 15 ~ 75wt%, borosilicate glass is 75 ~ 90wt% silicon oxide and 8 ~ 20
An LC composite part characterized by containing wt% of boron oxide. Incidentally, JP-A-58-135133, 58-135606, 58-
No. 135607, No. 58-135608, No. 58-135609,
It has been proposed that glass is added to ferrite to reduce shrinkage, but this one naturally has insufficient sintering density and mechanical strength. It is considered that this is because these publications only call it glass and do not disclose what composition of glass is used, and do not use borosilicate glass as in the present invention. In addition, JP-A-51-151331 and U.S. Pat.
Japanese Patent No. 500 discloses a ferrite containing 5% or less of lithium borosilicate glass. However, this has a small amount of glass, and the effect of the present invention cannot be realized. Further, JP-A-59-90915 discloses that in a chip component, a glass intermediate layer is provided between a conductive layer and an insulating layer, which is the same as the present invention. Since glass is provided as a separate layer instead of being mixed with, there are drawbacks such as a decrease in Q value and the inability to control the expansion coefficient when forming an inductor, for example. IV Specific Configuration of the Invention Hereinafter, the specific configuration of the present invention will be described in detail. The ferrite sintered body of the present invention contains ferrite and borosilicate glass, and more preferably contains boron oxide. Such a ferrite sintered body of the present invention can be fired at a low temperature at 950 ° C., particularly 900 ° C. or lower, and a sufficient sintered density can be obtained even at such a temperature, and it has high mechanical strength. The ferrite used in the ferrite sintered body of the present invention may be any of the known soft ferrites having a spinel structure. Generally, one of Ni, Cu, Mn, Zn and Fe is used.
Those containing one or more species are preferably used. Of these, Ni ferrite, Ni-Cu ferrite, and Ni ferrite are particularly effective for high frequencies and are capable of low-temperature sintering.
Ni-based ferrites such as -Zn ferrite, Ni-Cu-Zn ferrite, or those containing Li in these are preferable. In the case of Ni-based ferrite, the content of Ni is preferably 45 to 55 mol% in terms of NiO, and a part of this Ni is Cu and / or
Alternatively, Zn, Li or the like may be replaced by about 40 mol% or less. In addition, Co, Mn and the like may be contained in an amount of about 5 wt% or less of the whole. Further, Ca, Si, Bi, V, Pb and the like may be contained at about 1 wt% or less. In the ferrite sintered body of the present invention, the above borosilicate glass is added to such ferrite in an amount of 15 to 75 wt%, more preferably 25 to 35 wt%. If the added amount of borosilicate glass is less than 15 wt%, the effect of the present invention is not obtained, and if it exceeds 75 wt%, the glass component is too much,
This is because it adheres to a rug or the like during sintering and is difficult to handle, the shape change becomes extremely large, the degree of deformation increases, and the magnetic permeability also deteriorates. As the borosilicate glass to be used, various ones such as alumina borosilicate glass and alkali borosilicate glass can be used in addition to ordinary borosilicate glass, and have a predetermined composition described later. By using borosilicate glass of a predetermined composition,
INDUSTRIAL APPLICABILITY When the ferrite sintered body of the present invention is used for a chip inductor, an LC composite component, various magnetic cores, etc., it has high mechanical strength and excellent high frequency characteristics such as low loss and high Q value. . Such an effect is obtained only when a borosilicate glass having a predetermined composition is used, and is not realized with lead glass or high silicic acid glass. Such borosilicate glass contains 65 to 90 wt% silicon oxide (usually SiO ₂ ) and 8 to 30 wt% boron oxide (usually B
₂ O ₃ ). Among such borosilicate glasses, those particularly suitable for LC composite parts are 75-90 wt%, more preferably 80
~ 84wt% silicon oxide, more preferably 8 ~ 20wt%
It contains 14-18 wt% boron oxide. In such a case, when the silicon oxide is excessive and the boron oxide is too small with respect to the above amount range, the linear expansion coefficient becomes too small, and the sinterability is lowered, so that the sintered density becomes low. Further, if the silicon oxide is too small and the boron oxide is too large, the coefficient of linear expansion becomes too large. In addition, during sintering, foaming occurs, the sintered density becomes low, and the dimensions are changed, so that the specific resistance becomes high and the Q value becomes low. Further, such a composition does not have an adverse effect on the inner conductor and does not deteriorate the characteristics of the inner conductor. In addition, 5 wt% or less of aluminum oxide (usually Al ₂ O ₃ ) and 5 wt% or less of monovalent metal M ¹ oxides such as K, Na and Li (usually M ¹ ₂ O) in borosilicate glass. More than 1 kind, 5wt%
The following oxides of divalent metal M ² such as Ba, Ca, Sr, and Zn (usually M ²
You may contain 1 or more types of O). In another aspect of the ferrite sintered body of the present invention, boron oxide is further contained in addition to such a ferrite sintered body. In this case, the ferrite sintered body of the present invention preferably contains 10 wt% or less, particularly 0.1 to 10 wt%, more preferably 0.5 to 10 wt% of boron oxide in such ferrite. This is because the addition of boron oxide improves the sinterability and the mechanical strength, but if the content exceeds 10 wt%, the moisture resistance becomes insufficient, and the storage stability and durability are lacking. Boron oxide usually forms a solid solution with borosilicate glass in the firing process with a grain boundary separated from ferrite. The ferrite sintered body of the present invention is basically manufactured by a conventionally known method. That is, for example, Ni-Cu-Zn
In the case of ferrite, a certain amount of NiO, CuO, ZnO, Fe ₂ O ₃
A ferrite raw material powder such as the above and a predetermined amount of the above borosilicate glass are wet mixed by a ball mill or the like. The particle size of the powder used is about 0.1 to 10 μm. The wet-mixed product is usually dried by a spray drier and then calcined. Usually, this is wet pulverized by a ball mill until the powder particle size becomes about 0.01 to 0.5 μm, dried by a spray dryer, and various sintered bodies are formed by a known method. Further, in another embodiment of the present invention, boron oxide powder may be added to the obtained mixed ferrite powder, and a binder and a solvent may be added as necessary, and various sintered bodies may be formed by a known method. In addition, in order to form a paste into a sintered body, the obtained mixed ferrite powder or or boron oxide powder is added thereto, and this is dissolved in a binder such as ethyl cellulose and a solvent such as terpineol or butyl carbitol to paste. Good. These are molded into an appropriate shape, or printed or formed into a sheet such as a green sheet, and the temperature is 950 ° C or lower, for example, 8
Sinter at 50-930 ° C. The sintering time is usually about 0.5 to 4 hours. The boron oxide powder used has a particle size of about 0.1 to 10 μm. In the conventional case where borosilicate glass and boron oxide are not contained, the sintering temperature is 11 to obtain a sufficient sintered density.
Compared with the case where the temperature was set to about 00 ° C., by containing borosilicate glass in an amount of, for example, 30 wt% as in the present invention,
The same relative sintered density can be obtained at a temperature as low as ℃ or less. Further, by adding boron oxide in an amount of 10 wt% or less, a high sintered density can be obtained even at a lower temperature (850 to 950 ° C.), and more favorable results can be obtained in that the bending strength becomes high. In the above, a mixture of spinel ferrite and glass is obtained by forming a paste by using a mixed ferrite powder of borosilicate glass and a ferrite raw material, or by forming a paste obtained by adding boron oxide powder to the mixture and baking the mixture. However, it may be added when the ferrite powder, the glass powder and the boron oxide powder are formed into a paste. The ferrite sintered body produced in this way can be fired at low temperature, has excellent electromagnetic characteristics in terms of frequency characteristics, etc., has high mechanical strength, and can be used as an insulator for magnetic cores of various electronic components and chip inductors. It can be suitably used for a magnetic body, a magnetic or electromagnetic wave shield material, an attenuator and the like. Also, it has excellent workability. In addition to the use of a sintered body, it may be crushed and mixed with a binder for use as a shield material or the like. FIG. 1 shows an example of the chip inductor of the present invention. The chip inductor 1 of the present invention has a conventionally known structure as shown in FIG. 1, and is formed by alternately laminating the internal conductors 2 and the ferrite magnetic layers 3 formed in a predetermined pattern such as a spiral shape, to form a ferrite. The inner conductor having a predetermined winding shape and the number of turns is formed in the magnetic layer, and both ends of the inner conductor 2 are connected to the outer electrodes 41 and 45, which are manufactured by a conventionally known method. The paste for the ferrite magnetic layer of the chip inductor 1 can be manufactured in the same manner as the paste for a ferrite sintered body described above. This ferrite magnetic layer paste is mixed with Ag or Ag-
An internal conductor paste such as Pd is alternately printed on, for example, PET so as to have each predetermined pattern on a substrate, or laminated by a green sheet or the like, 950 ° C. or less, preferably 850 to
The chip inductor 1 of the present invention can be obtained by sintering at 930 ° C. for 0.5 to 4 hours. The thus manufactured chip inductor 1 of the present invention has high mechanical strength because the ferrite magnetic layer contains borosilicate glass or boron oxide to enhance the sinterability. Also, the sintering temperature required to obtain the same sintering density may be lower than in the conventional case. Further, it has excellent characteristics in terms of high frequency characteristics such as electromagnetic characteristics. The number of layers of the ferrite magnetic layer 3 may be selected according to the purpose, but is usually 1 to 20 layers. The thickness per layer may be appropriately selected according to the purpose, but is usually 10 to
It is about 30 μm. The inner conductor 2 is made of, for example, Ag, Ag-
It is formed of a metal such as Pd, and its thickness is usually about 10 to 25 μm. Similarly, the external electrodes 41 and 45 can be formed of a metal such as Ag or Ag-Pd, and the thickness thereof is usually 10 to 300 μm.
Degree. FIG. 2 shows an example of the LC composite component of the present invention. The LC composite component 5 of the present invention is one in which the inductor section 6 and the capacitor section 7 are integrated. The inductor portion 6 is formed by laminating a ferrite magnetic layer 61 while interposing the internal conductors 65 formed in a predetermined pattern so as to conduct each other. Further, the capacitor section 7 laminated and integrated with the inductor section 6 has an internal electrode
75 and ceramic dielectric layers 71 are alternately laminated. In the example shown in FIG. 2, the inductor section 6 and the capacitor section 7 each have a plurality of Ls and Cs, and are provided with predetermined external electrodes 8 so as to form a predetermined LC circuit. The inductor section 6 of the LC composite component 5 of the present invention is similar to the chip inductor 1 shown in FIG. 1 described above, and can be fired at a low temperature and is excellent in frequency characteristics and mechanical strength. Moreover, by adding borosilicate glass to the ferrite magnetic layer and adjusting the content thereof,
Since the contraction rate can be adjusted, the contraction rate of the inductor section 6 and the contraction rate of the capacitor section 7 can be made to substantially coincide with each other to prevent warpage and peeling at the interface between the inductor and the capacitor during firing. is there. That is, the linear expansion coefficient of Ni-based ferrite as described above is usually 90 × 10 ^-7 ~ 115 × 10 ^-7 deg ^-1 , the addition of 15 to 75 wt% borosilicate glass, The rate can be 90 × 10 ⁷ to 70 × 10 ⁻⁷ deg ⁻¹ . This is almost the same as the linear expansion coefficient of 75 × 10 ^{−7 to} 85 × 10 ⁻⁷ deg ^{−1 of the} TiO ₂ -based dielectric material used for the dielectric layer 71 of the capacitor section 7 described later. Further, the shrinkage rate is about 15 to 20%, which is almost the same as 15 to 18% of the TiO ₂ -based dielectric material. Further, the inductor portion 6 is preferably made of boron oxide, preferably 10 wt.
% Or less, the sintered density of the inductor portion 6 increases, and the LC composite component 5 having high mechanical strength can be obtained. Various dielectric materials may be used as a material for forming the dielectric layer 71 of the capacitor unit 7, but Ti which mainly contains TiO ₂ may be used.
O ₂ systems are preferred. The TiO ₂ type _{NiO, CuO, Mn 3 O 4} , Al 2 O 3, MgO, SiO 2
And the like are preferably about 10 mol% or less in total in view of dielectric loss and change in coefficient of linear expansion. The contraction rate of the TiO ₂ -based dielectric layer 71 is about 15 to 18%. Then, by adding borosilicate glass to the above ferrite, the shrinkage rate can be made equivalent to this. The number of dielectric layers 71 of the capacitor section 7 may be determined according to the purpose, but is usually about 1 to 10. The thickness per layer is usually about 50 to 150 μm. Further, the internal electrode 75 of the capacitor portion may be formed of a metal such as Ag or Ag-Pd, and its thickness is usually about 5 to 15 μm. The number of stacked magnetic layers 61 may be selected according to the purpose, but is usually 1 to 20 layers. The thickness per layer may be appropriately selected according to the purpose, but is usually about 10 to 30 μm. Further, the inner conductor 65 is formed of a metal such as Ag, Ag-Pd or the like, and usually has a thickness of about 10 to 30 μm. The external electrode 8 can be formed of a metal such as Ag-Pd as described above, and the thickness thereof is usually about 10 to 300 μm. The LC composite component of the present invention is manufactured by a conventionally known printing method or green sheet method. That is, a ceramic magnetic layer, a dielectric layer, an internal electrode, and a conductor paste are prepared, and these are laminated layer by layer on a substrate such as PET by a printing method or a green sheet method. In this case, the dielectric layer 71 of the capacitor section 7 and the internal electrode
The paste of the inner conductor 75 and the inner conductor 65 of the inductor portion 6 and the paste of the outer electrode 8 may be prepared using a binder and a solvent. Using each of these pastes, a capacitor part and an inductor part are laminated and formed by a printing method or a green sheet method, and then cut into a predetermined shape and the laminated product is peeled from the substrate.
Baking is performed at 0 ° C or lower, for example, 850 to 930 ° C. Firing time is 0.5
Approximately 4 hours. After firing, the Ag paste is baked to form external electrodes. The size and the like of the LC composite component manufactured as described above may be selected according to the purpose. V Specific Effect of the Invention The ferrite sintered body of the present invention contains borosilicate glass. Therefore, sufficient sintering density can be obtained even at low temperature firing of 950 ° C or lower, and mechanical strength is high. Moreover, it is excellent in workability, and is also excellent in electromagnetic characteristics and high frequency characteristics. Further, since the chip inductor of the present invention uses the above ferrite sintered body as the magnetic layer, it can be fired at a low temperature, has high mechanical strength, and is excellent in electromagnetic characteristics and high frequency characteristics. Further, since the LC composite component of the present invention uses the chip inductor as an injector part, it can be fired at a low temperature, has high mechanical strength, and is excellent in electromagnetic characteristics and high frequency characteristics. In addition, the storage ratio of the inductor part and the capacitor part during sintering can be approximated by adjusting the amount of boron oxide added, so warping and peeling at the interface between both parts is based on the difference in shrinkage ratio during sintering. Can be avoided. Therefore, there is no problem that the component cannot be surface-mounted due to warpage or peeling. VI Specific Examples of the Invention Hereinafter, the present invention will be described in more detail with reference to specific examples of the present invention. Example 1 Ni-based ferrite and borosilicate glass or
A paste for a ferrite sintered body of the present invention was prepared by adding B ₂ O ₃ and. The Ni-based ferrite raw material used was a powder of NiO and Fe ₂ O ₃ having a particle size of 0.1 to 1.0 μm, 52 mol% in terms of NiO, Fe ₂ O
_It was blended so as to have a composition of 48 mol% in terms of ₃ . This ferrite raw material, average particle diameter 5 μm, SiO ₂ 80.3w
A borosilicate glass (glass I) powder having a composition of t%, B ₂ O ₃ 17.5 wt% and K ₂ O 2.2 wt% was wet-mixed using a ball mill. Next, the wet mixture was dried with a spray dryer, calcined at 850 ° C. to give granules, which were crushed with a ball mill and then dried with a spray dryer to give a powder having an average particle size of 0.1 μm. The obtained powder and / or B ₂ O with an average particle size of 5.0 μm
_The powder to which ₃ powders were added was dissolved in terpineol together with a predetermined amount of ethyl cellulose and mixed with a Henschel mixer to prepare a ferrite sintered body paste. This paste is printed on a PET substrate by the printing method, then the laminate is peeled from the substrate and baked at 900 ° C for 2 hours,
A rod-shaped sample of × 3.0 × 15.00 mm was obtained. Table 1 shows the relative sintering density (sintering density / theoretical density), linear expansion coefficient and shrinkage rate of the obtained sample. Table 1
The results of using the following borosilicate glass and comparative glass are also shown in Table 1. Comparison Glass II (high silicate _{glass) 95wt% SiO 2 -5wt% Na} 2 O Comparative Glass III (lead _{glass) 42wt% SiO 2 -52wt% PbO} -5.5wt% Al 2 O 3 -0.5wt% B 2 O 3 Glass IV (borosilicate glass) 70 wt% SiO ₂ −25.0 wt% B ₂ O ₃ 5 wt% Na ₂ O Comparative glass V (comparative borosilicate glass) 60 wt% SiO ₂ −35 wt% B ₂ O ₃ −5 wt% Na ₂ O Furthermore, as conventional materials, Fe ₂ O ₃ 45.5mol%, NiO 44mol
%, CuO 8 mol%, ZnO 2 mol%, CoO 0.6 mol% are also used (Sample No. 10). Sample No. 1 is only the above-mentioned ferrite. From the results shown in Table 1, sample Nos. 2 to 6 of the present invention
It can be seen that and No. 9 have a sufficient sintered density even when fired at a low temperature and have excellent mechanical strength. Also, the storage rate
It can be increased to 16.5 to 23.2%. This is almost the same as the shrinkage rate of 15 to 18% of the TiO ₂ -based dielectric material, and when used as an LC composite component, a good one without warpage, peeling, and cracks can be obtained. This is demonstrated in more detail in Example 3. Table 2 shows the relationship between the firing temperature and the relative sintering density of Samples No. 2 and No. 11. In addition, when cores were made for sample Nos. 2 and 8 and the frequency characteristics of magnetic loss were measured, it was found to be 500M.
Above Hz, the magnetic loss of sample No. 8 was more than double that of sample No. 2. Example 2 Next, the paste for ferrite sintered bodies of Sample Nos. 2, 4, 7, 8, 9, 10, and 11 was used as a magnetic layer, and Ag paste was used as an internal conductor. By the method, a chip inductor of 3.2 mm × 2.5 mm × 1.0 mm shown in FIG. 1 was produced. The thickness of each ferrite layer is 40 μm, and the thickness of the conductor layer is 20 μm.
m, its line width is 300 μm, and the coil has a major axis of 2.5 mm and a minor axis of 1.3 m.
It was made into an ellipse of m and laminated for 2.5 turns. The external electrodes were composed of Ag-Pd paste. The firing temperature was 870 ° C. for 2 hours. The Q value and the inductance at each frequency of the thus obtained chip inductor were measured. Table 3 shows the results. As the magnetic layer, Fe ₂ O ₃ 46 mol%, ZnO 44 mol%,
An air core coil using a non-magnetic material in which CoO and MnO are added at 1 wt% each to the composition of 10 mol% CuO is also shown. From the results shown in Table 3, it can be seen that the sample of the present invention has excellent frequency characteristics as compared with the comparative sample. Further, the one to which high silicate glass was added as the comparative glass II to the magnetic layer had lower strength than the other samples. Further, in sample No. 8 in which lead glass was added as the comparative glass III to the magnetic layer, lead diffused silver in the internal conductor layer, the electrode disappeared, or wire breakage occurred, and measurement was impossible. . In addition, a similar experiment was conducted using ferrite raw materials for various other Ni-
The same results were obtained even if the Zn ferrite was changed or the glass material was changed to various other borosilicate glasses and the content thereof was 30 wt%. Furthermore, the ferrite raw material Ni-Cu ferrite containing 25 wt% borosilicate glass, Ni-Cu-Zn ferrite containing 28 wt% borosilicate glass Ni-Cu-ZN
Similar results were obtained with -Li ferrite containing 23 wt% of borosilicate glass. Example 3 A paste for a magnetic layer of an LC composite component of the present invention was produced by adding borosilicate glass to Ni-based ferrite so as to be 10 to 80 wt% of the whole. The Ni-based ferrite raw material used was a powder of NiO, CoO, and Fe ₂ O ₃ having a particle size of about 0.1 to 1.0 μm.
It was 48 mol% in terms of e ₂ O ₃ , and was blended so as to have a composition containing 0.4 wt% of CoO. This ferrite raw material, average particle size 5 μm, SiO ₂ 82.0w
A borosilicate glass powder having a composition of t%, B ₂ O ₃ 16.0 wt%, Al ₂ O ₃ 0.3 wt% and K ₂ O 1.7 wt% was wet-mixed using a ball mill. Next, the wet mixture was dried with a spray drier and calcined at 800 ° C. to obtain granules. The granules were pulverized with a ball mill and then dried with a spray drier to obtain powder having an average particle diameter of 0.1 μm. Next, this powder was dissolved in terpineol together with a predetermined amount of ethyl cellulose and mixed with a Henschel mixer to prepare a paste for the inductor magnetic ceramic layer. This paste is printed on a PET substrate by a printing method, then the laminated product is peeled from the substrate and baked at 870 ° C for 2 hours,
A rod-shaped sample of 3.0 × 3.0 × 15.00 mm was obtained. Table 4 shows the linear expansion coefficient of the obtained sample. In addition, Table 4 also shows the results using the comparative glasses II, III and glass IV. Next, the shrinkage rate of the above sample was calculated. Table 5 shows the results. Tables 4 and 5 also show the values of the TiO ₂ -based dielectric layer of the capacitor section below. From these results, it is understood that according to the present invention, the coefficient of linear expansion and the coefficient of contraction can be made substantially equal to those of the TiO ₂ -based dielectric layer. Further, Table 6 below shows the initial magnetic permeability μi at 100 MHz. From the results shown in Table 6, it can be seen that according to the present invention, μi is reduced and the frequency characteristics on the high frequency side of the magnetic layer are improved. Next, powder having a composition of TiO ₂ 91 wt%, NiO, CuO, Mn ₃ O ₄ 3 wt% each and an average particle size of 0.1 to 1.0 μm was used, and the same binder and solvent as the above-mentioned magnetic layer paste were used. A paste for the dielectric layer of the capacitor part was prepared using the above. Magnetic layer paste containing 30 wt% of borosilicate glass,
For the above dielectric layer paste, for internal electrodes and conductors
The Ag paste was laminated by a printing method. The thickness of one layer of the inductor portion was 40 μm, the number of laminated layers was 10, the thickness of one layer of the capacitor portion was 100 μm, and the number of laminated layers was 2. The thickness of the internal electrodes and the conductor was 20 μm. 87 after printing lamination
Firing was performed at 0 ° C. for 2 hours. Then, slowly cool to 100MHz with 4 L and 3 C
4.5mm × 3.2mm × 1.5mm of the above high-pass filter circuit
Got LC composite parts. No warpage, peeling or cracking was observed at the interface between the capacitor and the inductor of the obtained LC composite part. Further, the characteristics of the inner conductor did not deteriorate. In addition, the frequency band used is 100-500MH with no additive.
While the z band was passed, the high frequency end of the component of the present invention extended to the high frequency side by about 500 MHz and was able to pass the 100 MHz to 1 GHz band. In contrast, the comparative glasses II, IV and SiO ₂
In the sample using, warpage, peeling, and cracks occurred. In Comparative Glass III, the characteristics of the internal conductor deteriorated. Table 7 shows the results of examining the number of defective products in 100 samples by observing warpage, peeling, and crack generation of each sample with a microscope. In addition, the resistance of the internal conductor after storage for 1000 hours at 40 ° C and relative humidity of 85 to 90% was measured, and the number of samples that changed from the initial resistance value to 10% or more is shown in Table 7 as the number per 100 samples. Write together. Example 4 In the same manner as in Example 3, a powder mixture of a ferrite raw material and borosilicate glass having the same composition was prepared. The obtained powder and B ₂ O ₃ powder having an average particle size of 5.0 μm were dissolved in terpionel together with a predetermined amount of ethyl cellulose and mixed with a Henschel mixer to prepare a paste for the inductor magnetic ceramic layer. This paste is printed on a PET substrate by the printing method, then the laminate is peeled from the substrate and baked at 870 ° C for 2 hours,
A rod-shaped sample of × 3.0 × 15.00 mm was obtained. Tables 8 and 9 show the linear expansion coefficient and the contraction rate of the obtained samples. Table 8 also shows the results using Comparative Glasses II, III and Glass IV below. Next, the shrinkage rate of the above sample was calculated. Table 9 shows the results. In addition, in Tables 8 and 9, the values of the TiO ₂ -based dielectric layers of the following capacitor portions are also shown. From these results, it is understood that according to the present invention, the coefficient of linear expansion and the coefficient of contraction can be made substantially equal to those of the TiO ₂ -based dielectric layer. Next, as shown in Table 10 below, the addition amount of B ₂ O ₃ was changed in the above sample, and the bending strength was measured. Table 10 shows the results. From the results shown in Table 10, it is clear that B ₂ O ₃ improves the mechanical strength. The moisture resistance was insufficient for the additive amount of 15 wt%. Further, Table 11 below shows the initial magnetic permeability μi at 100 MHz. From the results shown in Table 11, it can be seen that according to the present invention, μi is reduced and the frequency characteristics on the high frequency side of the magnetic layer are improved. Then, an LC composite part was obtained in the same manner as in Comparative Example 3. No warpage, peeling or cracking was observed at the interface between the capacitor and the inductor of the obtained LC composite part. Further, the characteristics of the inner conductor did not deteriorate. In addition, compared to the one with no added frequency band,
It was extended to the high frequency side of about 500MHz. In contrast, the comparative glasses II, IV and SiO ₂
In the sample using, warpage, peeling, and cracks occurred. In Comparative Glass III, the characteristics of the internal conductor deteriorated. Table 12 shows the number of warped, peeled and cracked out of 100 samples of each sample as the number of defective products.
In addition, the resistance of the internal conductor after storage for 1000 hours at 40 ° C and relative humidity of 85 to 90% was measured, and the number of samples that changed from the initial resistance value to 10% or more is shown in Table 12 as the number per 100 samples. Write together. From the above, the effect of the present invention is clear.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway front view showing an embodiment of a chip inductor of the present invention. FIG. 2 is a partially cutaway perspective view showing an embodiment of the LC composite component of the present invention. Explanation of symbols 1 …… Chip inductor, 2 …… Inner conductor, 3 …… Ferrite magnetic layer, 41,45 …… External electrode, 5 …… LC composite part, 6 …… Inductor part, 61 …… Ferrite magnetic layer, 65 …… inner conductor, 7 …… capacitor part, 71 …… dielectric layer, 75 …… inner electrode, 8 …… outer electrode

Continuation of front page    (72) Inventor Takeshi Nomura               1-13-1 Nihonbashi, Chuo-ku, Tokyo               IDK Corporation                (56) References JP-A-58-172803 (JP, A)                 JP-A-58-151331 (JP, A)

Claims (1)

(57) [Claims] Contains ferrite and borosilicate glass, the content of borosilicate glass is 15-75wt%, borosilicate glass is 65-90wt% silicon oxide and 8-30
A ferrite sintered body characterized by containing wt% of boron oxide. 2. Borosilicate glass is 75-90 wt% silicon oxide and 8
Claim 1 containing ~ 20wt% boron oxide
The ferrite sintered body according to the item. 3. The ferrite sintered body according to claim 1 or 2, wherein the ferrite is a Ni-based ferrite. 4. Contains ferrite, borosilicate glass and boron oxide, the content of borosilicate glass is 15 ~ 75wt%, borosilicate glass is 65 ~ 90wt% silicon oxide and 8 ~ 30wt%
% Of boron oxide, a ferrite sintered body characterized by containing. 5. The ferrite sintered body according to claim 4, wherein the content of boron oxide is 10 wt% or less. 6. Borosilicate glass is 75-90 wt% silicon oxide and 8
Claim 4 containing ~ 20wt% boron oxide
Or a ferrite sintered body according to item 5. 7. The ferrite sintered body according to any one of claims 4 to 6, wherein the ferrite is a Ni-based ferrite. 8. In a chip inductor in which a ceramic magnetic layer and an internal conductor layer are laminated, the ceramic magnetic layer contains ferrite and borosilicate glass, the content of borosilicate glass is 15 to 75 wt%, and the borosilicate glass is 65 to 90wt% silicon oxide and 8-30
A chip inductor containing wt% boron oxide. 9. Borosilicate glass is 75-90 wt% silicon oxide and 8
Claim 8 containing ~ 20wt% boron oxide
The ferrite sintered body according to the item. 10. The chip inductor according to claim 8 or 9, wherein the ferrite is a Ni-based ferrite. 11. In a chip inductor in which a ceramic magnetic layer and an internal conductor layer are laminated, the ceramic magnetic layer contains ferrite, borosilicate glass, and boron oxide, the borosilicate glass content is 15 to 75 wt%, and the borosilicate glass is , 65-90wt% silicon oxide and 8-30
A chip inductor containing wt% boron oxide. 12. 12. The chip inductor according to claim 11 or 11, wherein the content of boron oxide is 10 wt% or less. 13. 13. The chip inductor according to claim 11, wherein the ferrite is a Ni-based ferrite. 14． In a ceramic LC composite component that integrates a capacitor part in which a ceramic dielectric layer and an electrode layer are laminated and an inductor part in which a ferrite magnetic layer and an internal conductor layer are laminated, the ceramic magnetic layer is composed of ferrite and borosilicate glass. Contains, the content of borosilicate glass is 15 ~ 75wt%, borosilicate glass is 75 ~ 90wt% silicon oxide and 8 ~ 20
An LC composite part characterized by containing wt% of boron oxide. 15. 15. The LC composite component according to claim 14, wherein the ferrite is a Ni-based ferrite. 16. The LC composite component according to claim 14 or 15, wherein the dielectric layer is a TiO ₂ system. 17． 17. The LC composite component according to claim 14, wherein the capacitor part and the inductor part are co-fired and integrated. 18. In a ceramic LC composite component that integrates a capacitor part in which a ceramic dielectric layer and an electrode layer are laminated and an inductor part in which a ceramic magnetic layer and an internal conductor layer are laminated, the ceramic magnetic layer is composed of ferrite, borosilicate glass, and oxide. Boron and borosilicate glass content is 15 ~ 75wt%, borosilicate glass is 75 ~ 90wt% silicon oxide and 8 ~ 20wt%
% Of boron oxide, LC composite parts characterized by containing. 19. 19. The LC composite component according to claim 18, wherein the content of boron oxide is 10 wt% or less. 20. 20. The LC composite component according to claim 18 or 19, wherein the ferrite is a Ni-based ferrite. 21. 21. The LC composite component according to any one of claims 18 to 20, wherein the dielectric layer is a TiO ₂ system. 22. 22. The LC composite component according to claim 18, wherein the capacitor portion and the inductor portion are co-fired and integrated.