KR100219319B1 - Elements for laminated-type ceramic inductors - Google Patents
Elements for laminated-type ceramic inductors Download PDFInfo
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- KR100219319B1 KR100219319B1 KR1019970017244A KR19970017244A KR100219319B1 KR 100219319 B1 KR100219319 B1 KR 100219319B1 KR 1019970017244 A KR1019970017244 A KR 1019970017244A KR 19970017244 A KR19970017244 A KR 19970017244A KR 100219319 B1 KR100219319 B1 KR 100219319B1
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- ferrite
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- 239000000919 ceramic Substances 0.000 title claims abstract description 9
- 239000000463 material Substances 0.000 claims abstract description 17
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 15
- 229910017518 Cu Zn Inorganic materials 0.000 claims abstract description 12
- 229910017752 Cu-Zn Inorganic materials 0.000 claims abstract description 12
- 229910017943 Cu—Zn Inorganic materials 0.000 claims abstract description 12
- 150000001622 bismuth compounds Chemical class 0.000 claims description 9
- 150000001869 cobalt compounds Chemical class 0.000 claims description 8
- 150000002642 lithium compounds Chemical class 0.000 claims description 8
- 229910015902 Bi 2 O 3 Inorganic materials 0.000 claims description 3
- 229910020599 Co 3 O 4 Inorganic materials 0.000 claims description 3
- TVZPLCNGKSPOJA-UHFFFAOYSA-N copper zinc Chemical compound [Cu].[Zn] TVZPLCNGKSPOJA-UHFFFAOYSA-N 0.000 claims 1
- 239000000654 additive Substances 0.000 abstract description 8
- 230000000996 additive effect Effects 0.000 abstract description 7
- 229910052797 bismuth Inorganic materials 0.000 abstract description 2
- 229910052744 lithium Inorganic materials 0.000 abstract description 2
- 230000035699 permeability Effects 0.000 description 14
- 239000000843 powder Substances 0.000 description 9
- 239000000203 mixture Substances 0.000 description 3
- 239000004809 Teflon Substances 0.000 description 2
- 229920006362 Teflon® Polymers 0.000 description 2
- 239000011324 bead Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910018054 Ni-Cu Inorganic materials 0.000 description 1
- 229910018481 Ni—Cu Inorganic materials 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- ZXQYGBMAQZUVMI-GCMPRSNUSA-N gamma-cyhalothrin Chemical class CC1(C)[C@@H](\C=C(/Cl)C(F)(F)F)[C@H]1C(=O)O[C@H](C#N)C1=CC=CC(OC=2C=CC=CC=2)=C1 ZXQYGBMAQZUVMI-GCMPRSNUSA-N 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F17/00—Fixed inductances of the signal type
- H01F17/0006—Printed inductances
- H01F17/0013—Printed inductances with stacked layers
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/26—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on ferrites
- C04B35/2608—Compositions containing one or more ferrites of the group comprising manganese, zinc, nickel, copper or cobalt and one or more ferrites of the group comprising rare earth metals, alkali metals, alkaline earth metals or lead
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/453—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zinc, tin, or bismuth oxides or solid solutions thereof with other oxides, e.g. zincates, stannates or bismuthates
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
- H01F1/342—Oxides
- H01F1/344—Ferrites, e.g. having a cubic spinel structure (X2+O)(Y23+O3), e.g. magnetite Fe3O4
Abstract
본 발명은 Ni-Cu-Zn계 페라이트에 첨가물로서 Co, Bi, Li의 화합물을 동시에 소량 첨가하여서 된 초 투자율 120이상, 25MHz 이상의 고주파에서의 품질 계수가 100이상을 가지는 적층 세라믹 인덕터용 소재를 제공하기 위한 것이다.The present invention provides a material for a multilayer ceramic inductor having a super-permeability of 120 or more and a high quality factor of 25 or more at a high frequency of at least 25 MHz, which is obtained by simultaneously adding a small amount of Co, Bi, and Li as an additive to a Ni-Cu-Zn-based ferrite. It is to.
Description
본 발명은 높은 초 투자율 및 높은 품질 계수를 가지는 적층 세라믹 인덕터용 소재에 관한 것으로서, 더욱 상세하게는, Ni-Cu-Zn계 페라이트에 첨가물로서 Co, Bi, Li의 화합물에동시에 소량 첨가함으로써 초 투자율 120이상, 25MHz 이상의 고주파에서의 품질 계수가 100이상을 가지는 적층 세라믹 인덕터용 소재에 관한 것이다.The present invention relates to a material for a multilayer ceramic inductor having a high super permeability and a high quality factor, and more particularly, a super permeability by adding a small amount to a compound of Co, Bi, Li simultaneously as an additive to a Ni-Cu-Zn-based ferrite. The present invention relates to a multilayer ceramic inductor material having a quality factor of 120 or more and a high frequency of 25 MHz or more.
칩 인덕터는 칩 비드와는 달리 가장 중요한 특성으로 고 품질 계수가 얻어져야만 하는 부품이다. 칩 비드는 전자회로에서 발생되는 고주파 노이즈를 제거하는 기능을 하기 위해 저 품질 계수를 가지는 것이 요구되는 부품인데 반해, 칩 인덕터는 전자회로에서 칩 콘덴서 등과 복합적으로 구성되어 저역 통과 필터(low pass filter), 고역 통과 필터(high pass filter), 대역 통과 필터(band pass filter)를 구성하여 일정 주파수의 신호만을 퍼터링 하는 역할을 하므로 손실이 적어야만 깨끗한 신호를 얻을수 있으며, 이때 손실의 역수(1/손실)를 품질 계수라고 하므로 고 품질 계수를 가져야만 한다. 따라서, 칩 인덕터의 경우는 품질 계수가 가장 중요한 특성이며, 높은 품질 게수값을 넓은 주파수 범위에서 가지는 것이 중요하다.Chip inductors, unlike chip beads, are the most important feature and require high quality factor to be obtained. Chip bead is a component that is required to have a low quality factor in order to remove the high frequency noise generated in the electronic circuit, whereas the chip inductor is composed of a chip capacitor and the like in the electronic circuit is a low pass filter It consists of a high pass filter and a band pass filter to putter only a signal of a certain frequency, so that only a small loss can be used to obtain a clean signal. ) Is called the quality factor, so it must have a high quality factor. Therefore, in the case of the chip inductor, the quality factor is the most important characteristic, and it is important to have a high quality coefficient value in a wide frequency range.
또한, 칩 인덕터에서 요구되는 중요 특성을 초 투자율이 있다. 칩 인덕터용 소재의 초 투자율은 사용 주파수 대역에 따라 30에서 150정도의 범위의 것이 사용되고 있으나, 고 품질 계수 특성을 기본적으로가지면서 낮은 초 투자율을 가지는 소재를 얻는 것은 쉬우나, 고 품질 계수 특성을 기본적으로 가지면서 높은 초 투자율을 가지는 소재를 얻는 것은 매우 어렵다. 이러한 이유는 고 품질 계수를 얻기 위해 첨가하는 첨가제가 초 투자율을 낮추는 적용을 하기 때문이다.In addition, there is an ultra-permeability of important characteristics required in the chip inductor. Although the super permeability of the chip inductor material is in the range of 30 to 150 depending on the frequency band used, it is easy to obtain a material having a low super permeability while basically having a high quality coefficient characteristic, It is very difficult to obtain a material with high ultra-permeability while having. This is because additives added to obtain high quality factors have applications that lower the initial permeability.
기존의 칩 인덕터용 소재는 고 품질 계수를 가지는 경우에는 초 투자율 및 소결밀도가 낮고, 초 투자율 및 소결 밀도가 높은 경우에는 품질 계수가 낮은 단점을 가지고 있었다. 즉, 품질 계수가 큰 원료 분말을 소결한 경우 밀도가 낮고, 초 투자율이 낮게 나타나는 것이 기존 분말의 경우였다. 따라소, 품질 계수를 높이게 되면 초 투자율이 감소하고, 소결 밀도가 낮아져 동시에 소결후의 강도가 낮아지게 되어 제품 사용시 균열이 발생하는 등 낮은 강도에 의한 문제가 대두되고 있었다. 이는 고 품질 계수를 얻기 위해 첨가하는 첨가제가 초투자율 및 소결 밀도를 낮추는 작용을 하기 때문이다. 이러한 단점을 보완하는 방법으로 기존의 경우에는 연료 분말을 매우 미세하게(1㎛ 이하) 분쇄하여 사용함으로써 소결 밀도가 낮아지지 않게 하였으나, 분말을 미세하게 분쇄하는 것이 원가 상승의 원인이 되므로 우수한 해결 방안이 될 수 없었다.Conventional chip inductor materials have the disadvantages of low initial permeability and sintered density when they have high quality factor, and low quality factors when they have high permeability and sintered density. In other words, when the raw material powder having a high quality factor was sintered, the density was low and the super-permeability was low. Therefore, when the quality factor is increased, the super-permeability is decreased, the sinter density is lowered, and the strength after sintering is lowered, and the problem of low strength has arisen such as cracking when using the product. This is because the additive added to obtain a high quality factor serves to lower the initial permeability and the sintered density. In order to compensate for these disadvantages, the sintered density is not reduced by pulverizing the fuel powder very finely (less than 1 μm). However, finely pulverizing the powder causes an increase in cost. Could not be this.
또한, 기존 소재는 고 품질 계수를 가진다고 하더라도 좁은 주파수 대역에서만 높은 값을 가지는 단점을 가지고 있었다. 도 1에서 보듯이 고 품질 계수를 나타내는 주파수 대역이 여러 가지가 있을 수 있으며, 도 1의 a와 같이 넓은 주파수 대역에서 고 품질 계수를 가질 경우 넓은 주파수 대역에서 칩 인덕터가 사용될 수 있게 되므로 중요한 특성이나 기존의 소재는 고 품질 계수를 가지는 주파수 대역이 협대역인 단점을 가지고 있다.In addition, the existing material had a disadvantage of having a high value only in a narrow frequency band even if it has a high quality factor. As shown in FIG. 1, there may be several frequency bands representing high quality coefficients. When the high frequency coefficients are used in a wide frequency band as shown in FIG. 1A, a chip inductor may be used in a wide frequency band. Existing materials have the disadvantage that the frequency band with high quality factor is narrow band.
본 발명에서는 상기와 같이 칩 인덕터용 소재로 사용되기 위해 요구되는 특성인 고품질 계수, 고 초투자율, 고 소결밀도, 넓은 주파수 대역에서의 고품질계수 등의 특성을 만족하는 페라이트 조성을 개발하기 위해 Ni-Cu-Zn 페라이트에 비스무스 화합물, 리늄 화합물, 코발트 화합물을 동시에 첨가하게 되면 상기에 언급한 3가지 특성, 즉 고소결밀도, 고 투자율 및 고 품질계수를 동시에 얻을 수 있음을 알게 되어 본 발명에 이르게 되었다.In the present invention, Ni-Cu to develop a ferrite composition that satisfies characteristics such as high-quality coefficient, high super-permeability, high sintered density, high-quality coefficient in a wide frequency band, which are required to be used as the material for the chip inductor as described above When the bismuth compound, the linium compound, and the cobalt compound are simultaneously added to -Zn ferrite, it has been found that the three characteristics mentioned above, that is, high sinter density, high permeability, and high quality coefficient, can be obtained simultaneously.
제1은 소재별 주파수에 따른 품질 계수 분산 특성을 나타낸 그래프이다.The first is a graph showing the quality coefficient dispersion characteristics according to the frequency of each material.
본 발명은 비스무스 화합물, 리튬 화합물 및 코발트 화합물이 함유된 Ni-Cu-Zn 계 페라이트를 주성분으로 하는 적층 세라믹 인덕터용 소재인 것을 특징으로 한다.The present invention is characterized in that it is a material for a multilayer ceramic inductor containing Ni-Cu-Zn-based ferrite containing a bismuth compound, a lithium compound and a cobalt compound as a main component.
본 발명에서 Ni-Cu-Zn계 페라이트의 조성은 (NixCuyZnz)1+w(Fe2O3)1-w로서, 여기서, 0.15≤X≤0.25, 0.15≤Y≤0.25 0.55≤Z≤0.65, 0.01≤W≤0.02를 가지며 X+Y+Z=1이다.In the present invention, the composition of the Ni-Cu-Zn-based ferrite is (Ni x Cu y Zn z ) 1 + w (Fe 2 O 3 ) 1-w , where 0.15 ≦ X ≦ 0.25, 0.15 ≦ Y ≦ 0.25 0.55 ≦ Z ≦ 0.65, 0.01 ≦ W ≦ 0.02 and X + Y + Z = 1.
본 발명에서 사용하는 비스무스 화합물은 고 소결밀도를 얻기 위한 첨가제로서, 예를들면 Bi2O3또는 Bi2O5가 있고, 리튬 화합물은 고 투자율을 얻기 위한 첨가제로서 예를 들면, LiO, LiCO2또는 Li2CO3가 있으며, 코발트 화합물은 고 품질계수를 얻기위한 첨가제로서, 예를 들면 Co2O3, Co3O4또는 CoO가 있다.The bismuth compound used in the present invention is an additive for obtaining a high sintered density, for example, Bi 2 O 3 or Bi 2 O 5 , the lithium compound is an additive for obtaining a high permeability, for example, LiO, LiCO 2 Or Li 2 CO 3 , and the cobalt compound is an additive for obtaining a high quality factor, for example, Co 2 O 3 , Co 3 O 4, or CoO.
상기 비스무스 화합물은 Ni-Cu-Zn계 페라이트에 대해 0.5 내지 4중량%, 바람직하게는 1.5 내지 2.5중량%, 상기 리튬 화합물은 Ni-Cu-Zn계 페라이트에 대해 0.01 내지 1중량%, 바람직하게는 0.2 내지 0.3중량%, 그리고 코발트 화합물은 Ni-Cu-Zn계 페라이트에 대해 0.01 내지 10중량%를 첨가하는 것이 바람직하다.The bismuth compound is 0.5 to 4% by weight based on Ni-Cu-Zn ferrite, preferably 1.5 to 2.5% by weight, the lithium compound is 0.01 to 1% by weight based on Ni-Cu-Zn ferrite 0.2 to 0.3% by weight, and the cobalt compound is preferably added to 0.01 to 10% by weight relative to the Ni-Cu-Zn-based ferrite.
본 발명에 따르면, 비스무스 화합물을 상기 범위를 벗어나서 첨가하게 되면 초투자율의 증가 효과를 얻을 수 없고, 리튬 화합물을 상기 범위를 벗어나서 첨가하게 되면 소결 밀도의 증가 효과를 얻을 수 없게 된다. 상기 비스무스 화합물과 리튬 화합물을 상기 범위로 첨가하게 되면 소결밀도는 약 5.2, 초투자율을 약 400까지 얻을 수 있다.According to the present invention, when the bismuth compound is added outside the above range, the effect of increasing the initial permeability cannot be obtained, and when the lithium compound is added outside the above range, the increase of the sintered density cannot be obtained. When the bismuth compound and the lithium compound are added in the above ranges, the sintered density may be about 5.2 and an initial permeability of about 400 may be obtained.
한편, 상기 코발트 화합물의 첨가량을 0.01중량% 미만으로 첨가할 경우에는 품질계수 특성이 10이하로 낮아 인덕터로서 좋은 특성을 나타내지 못하며, 10중량%를 초화하여 첨가할 경우에는 품질계수 특성 및 밀도 특성에는 문제가 없으나 초투자율이 10이하로 낮아져 인덕터로서 좋은 특성을 나타내지 못하게 된다.On the other hand, when the addition amount of the cobalt compound is added less than 0.01% by weight, the quality coefficient characteristics are less than 10, which does not show good characteristics as an inductor. There is no problem, but the initial permeability is lowered below 10, which does not show good characteristics as an inductor.
이하 실시예에 의해 본 발명을 더욱 상세히 설명하면 다음과 같다.Hereinafter, the present invention will be described in more detail with reference to the following examples.
[실시예]EXAMPLE
[실시예 1 내지 3(비교예) 1][Examples 1 to 3 (Comparative Examples) 1]
모재 페라이트로서 Fe2O349.9몰%, NiO17몰%, CuO 10몰%, ZnO 15몰%의 비율로 분말을 평량하여 얻은 분말 500g에 대해 스테인레스 스틸 볼 1000g과 물 700g을 2ℓ의 테프론통에 담아 15시간 동안 혼합한 후 100℃에서 20시간 건조하여 균일한 혼합 분말을 제조한 후 750℃에서 1시간 가소성을 실시하여 가소 분말을 제조하였다.As a base material ferrite, 1000g of stainless steel balls and 700g of water were put in a 2 L Teflon container for 500 g of powder obtained by weighing powders at a ratio of 49.9 mol% of Fe 2 O 3 , 17 mol% of NiO, 10 mol% of CuO, and 15 mol% of ZnO. After mixing for 15 hours, the mixture was dried at 100 ° C. for 20 hours to prepare a uniform mixed powder, and then calcined at 750 ° C. for 1 hour to prepare a calcined powder.
이 분말에 대해 Bi2O32중량%, Li2CO30.25중량%를 함께 넣고, 추가로 Co3O4를 0.01중량%(실시예 1), 0.1중량%(실시예 2) 및 10중량%(실시예 3)를 첨가하였다. 이때도 분말 : 스테인레스 스틸 : 물비를 1 : 2 : 1.4로 하여 2ℓ테프론 통속에 넣고, 20시간 동안 분쇄하고 100℃에서 건조하였다.2% by weight of Bi 2 O 3 and 0.25% by weight of Li 2 CO 3 were added together with the powder, and 0.01% by weight of Co 3 O 4 (Example 1), 0.1% by weight (Example 2) and 10% by weight. % (Example 3) was added. Also in this case, the powder: stainless steel: water ratio was 1: 2: 1.4, placed in a 2 L teflon tube, pulverized for 20 hours, and dried at 100 ° C.
이 분말을 500g/cm2의 압력으로 성형하여 토로이달 시편을 만들고 900℃에서 1시간 소결하여 소결시편을 제조하여 그 특성치를 표 1에 나타내었으며, 기존의 제품(비교예 1)을 트로이달 형태로 가공하여 그 특성치를 측정하여 그 값을 다음 표 1에 나타내었다.The powder was molded at a pressure of 500 g / cm 2 to form a toroidal specimen, and then sintered at 900 ° C. for 1 hour to prepare a sintered specimen. The characteristics thereof are shown in Table 1, and the conventional product (Comparative Example 1) was obtained in the form of a trojan. After processing by measuring the characteristic value is shown in Table 1 below.
본 발명은 Ni-Cu-Zn계 페라이트에 첨가물로서 Co, Bi, Li의 화합물을 동시에 소량 첨가함으로써 된 초 투자율 120이상, 25MHz 이상의 고주파에서의 품질 계수가 100이상을 가지는 적층 세라믹 인덕터용 소재를 얻을 수 있는 효과가 있다.The present invention provides a multilayer ceramic inductor material having an ultra-low permeability of 120 or more and a high frequency coefficient of 25 MHz or more, which is obtained by simultaneously adding a small amount of Co, Bi, and Li as an additive to Ni-Cu-Zn ferrite. It can be effective.
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