KR20000018655A - Composite material for chip inductor - Google Patents
Composite material for chip inductor Download PDFInfo
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- KR20000018655A KR20000018655A KR1019980036331A KR19980036331A KR20000018655A KR 20000018655 A KR20000018655 A KR 20000018655A KR 1019980036331 A KR1019980036331 A KR 1019980036331A KR 19980036331 A KR19980036331 A KR 19980036331A KR 20000018655 A KR20000018655 A KR 20000018655A
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- 239000002131 composite material Substances 0.000 title claims abstract description 16
- 239000003989 dielectric material Substances 0.000 claims abstract description 17
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 16
- 229910018605 Ni—Zn Inorganic materials 0.000 claims abstract description 5
- 229910007565 Zn—Cu Inorganic materials 0.000 claims description 7
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims 1
- 238000000034 method Methods 0.000 claims 1
- 239000000696 magnetic material Substances 0.000 abstract description 17
- 239000000463 material Substances 0.000 abstract description 9
- 238000002156 mixing Methods 0.000 abstract description 6
- 229910052596 spinel Inorganic materials 0.000 abstract description 5
- 239000011029 spinel Substances 0.000 abstract description 5
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 229910002113 barium titanate Inorganic materials 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 230000035699 permeability Effects 0.000 description 6
- 239000004020 conductor Substances 0.000 description 3
- 238000001354 calcination Methods 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- 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
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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
- C04B35/26—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
- C04B35/26—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
- C04B35/2633—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 containing barium, strontium or calcium
-
- 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
-
- 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
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Power Engineering (AREA)
- Ceramic Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
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- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Coils Or Transformers For Communication (AREA)
Abstract
Description
본 발명은 칩인덕터에 적용할 수 있는 복합재료에 관한 것으로, 보다 상세하게는 스피넬 구조를 가지는 자성체와 비자성체 물질을 혼합하여 얻어지는 복합재료에 관한 것이다.The present invention relates to a composite material that can be applied to a chip inductor, and more particularly to a composite material obtained by mixing a magnetic material and a nonmagnetic material having a spinel structure.
일반적으로 자성체 재료를 사용한 칩인덕터의 경우 재료고유의 특성인 투자율의 주파수특성 및 Q특성에 의해 사용주파수 대역이 결정된다. 기존의 스피넬구조를 가지는 칩인덕터의 경우 그 사용주파수 대역이 50MHz이하의 영역에서 사용되며 그 이상의 주파수 대역에서는 Q값의 급격한 저하로 인해 인덕터로서 사용하는 것이 곤란하다는 문제가 있었다.In general, in the case of a chip inductor using a magnetic material, the frequency band used is determined by the frequency characteristic and the Q characteristic of permeability, which are inherent to the material. In the case of a chip inductor having a conventional spinel structure, the frequency band of the chip inductor is used in a range of 50 MHz or less, and there is a problem that it is difficult to use it as an inductor due to a sharp decrease in the Q value in the frequency band above.
또한, 일반적으로 유전체 재료를 사용한 칩인덕터의 경우 내부도체에 의해 결정되는 Q의 주파수특성 및 Q의 절대값에 의해 사용주파수 대역이 결정된다. 이같은 유전체 재료를 사용하는 경우 그 사용주파수대역은 900MHz이상이며 저주파수 영역에서는 Q값이 낮아 사용하는 것이 곤란하다는 문제가 있었다.In general, in the case of a chip inductor using a dielectric material, the frequency band of use is determined by the frequency characteristic of Q and the absolute value of Q determined by the inner conductor. In the case of using such a dielectric material, the use frequency band is more than 900MHz and there is a problem that it is difficult to use because the Q value is low in the low frequency region.
따라서, 종래에는 50-900MHz의 영역에서 사용가능한 칩인덕터를 구현하는 것이 어려웠다.Therefore, it has been difficult to implement a chip inductor usable in the range of 50-900 MHz.
이에 본 발명자들은 상기 문제점을 해결하기 위해 연구와 실험을 거듭하고 그 결과에 근거하여 본 발명을 제안하게 된 것으로, 본 발명은 자성체 재료와 유전체 재료를 일정비율로 혼합함으로써, 기존의 자성체 칩인덕터와 저유전율 재료로 만든 칩인덕터 사이의 주파수대역에서 사용가능한 칩인덕터 부품에 적용할 수 있는 복합재료를 제공하고자 하는데, 그 목적이 있다.In order to solve the above problems, the present inventors have repeatedly conducted research and experiments and propose the present invention based on the results. The present invention mixes a magnetic material and a dielectric material at a predetermined ratio, and the existing magnetic chip inductor It is an object of the present invention to provide a composite material applicable to chip inductor components that can be used in the frequency band between chip inductors made of low dielectric constant materials.
도 1은 적층형의 칩부품 형성을 위한 적층의 일예를 보이는 개략구성도1 is a schematic configuration diagram showing an example of lamination for forming a multilayer chip component;
도 2는 칩부품의 외관을 보이는 모식도2 is a schematic view showing the appearance of the chip component
도 3은 종래 Ni-Zn-Cu페라이트 자성체를 이용한 저주파용 칩인덕터의 주파수특성을 보이는 그래프3 is a graph showing the frequency characteristics of a low-frequency chip inductor using a conventional Ni-Zn-Cu ferrite magnetic material
도 4는 종래의 Al2O3계 저유전율 재료를 이용한 고주파용 칩인덕터의 주파수특성을 보이는 그래프4 is a graph showing the frequency characteristics of a high-frequency chip inductor using a conventional Al 2 O 3 -based low dielectric constant material
도 5는 본 발명에 의한 칩인덕터의 주파수특성을 보이는 그래프5 is a graph showing the frequency characteristics of the chip inductor according to the present invention
*도면의 주요부분에 대한 부호의 설명** Description of the symbols for the main parts of the drawings *
1...시트(sheet) 2...도체1 ... sheet 2 ... conductor
3...관통홀 10...칩 부품3.Through hole 10 ... Chip parts
15...외부전극 16...소결체15 External electrode 16 Sintered body
상기 목적을 달성하기 위한 본 발명은 Ni-Zn계 페라이트 또는 Ni-Zn-Cu계 페라이트에 유전체재료를 20-40wt%의 비율로 함유시키는 것을 특징으로 하는 복합재료에 관한 것이다.The present invention for achieving the above object relates to a composite material characterized in that the dielectric material is contained in the Ni-Zn-based ferrite or Ni-Zn-Cu-based ferrite at a ratio of 20-40wt%.
이하, 본 발명을 상세히 설명한다.Hereinafter, the present invention will be described in detail.
본 발명은 기존의 스피넬구조를 가지는 자성체 재료에 유전체 재료를 함유시켜 복합재료로 하는 것이다.The present invention provides a composite material by containing a dielectric material in a magnetic material having a conventional spinel structure.
상기 스피넬구조를 가지는 자성체 재료로서는 Ni-Zn계 페라이트 또는 Ni-Zn-Cu계 페라이트를 들 수 있는데, 이들은 통상적으로 적용되는 것을 사용할 수 있다.Examples of the magnetic material having the spinel structure include Ni-Zn ferrites and Ni-Zn-Cu ferrites.
즉, 일예를 들면, Fe2O3: 48-52mole%, NiO: 35-51mole%, CuO: 0-15mole%, ZnO: 1-5mole%을 주성분으로 하며, 이들 원료를 일정비율로 계량하고, 습식혼합하고, 건조한 후, 약 650-800℃의 온도에서 2-4hr 정도 하소한 다음, 볼밀등으로 분쇄하여 0.3-0.7μm정도가 되도록 하여 페라이트로 합성하는 것이다. 이와같이 하여 얻어진 Ni-Zn 또는 Ni-Zn-Cu페라이트의 투자율은 10-50정도이다.That is, for example, Fe 2 O 3 : 48-52mole%, NiO: 35-51mole%, CuO: 0-15mole%, ZnO: 1-5mole% as a main component, these raw materials are weighed at a constant rate, After wet mixing, drying, and calcining at a temperature of about 650-800 ° C. for about 2-4 hr, pulverizing with a ball mill or the like to make 0.3-0.7 μm and synthesizing ferrite. The permeability of Ni-Zn or Ni-Zn-Cu ferrite thus obtained is about 10-50.
상기 자성체재료와 유전체재료의 배합은 자성체재료에 유전체재료를 20-40wt%의 비율로 배합하여 행한다.The mixing of the magnetic material and the dielectric material is performed by mixing the dielectric material in the proportion of 20-40 wt% with the magnetic material.
상기 유전체 재료의 함량이 20%미만이면 저주파수에서 인덕턴스의 공진점이 생길 수 있고, Q(품질계수)가 최고로 되는 주파수도 저주파로 이동되는 문제점이 생기며, 40%를 초과하면 Q의 절대값이 너무 많이 저하하게 되는 문제점이 있기 때문에, 본 발명에서는 배합비율을 20-40wt%로 하는 것이다.If the content of the dielectric material is less than 20%, a resonance point of inductance may occur at a low frequency, and a frequency at which the Q (quality factor) becomes the highest may also be shifted to a low frequency. If the content exceeds 40%, the absolute value of Q is too high. Since there is a problem of lowering, in the present invention, the blending ratio is set to 20-40 wt%.
상기 유전체재료는 통상적으로 적용되는 비자성재료를 20-40wt%의 비율로 하여 사용할 수 있는데, 예를들면, BaTiO3, Al2O3계 재료 등이 바람직하다. 이러한 유전체재료로서는 상기 자성체재료와 함께 합성할 때, 페라이트의 특성열화가 일어나지 않는 것이 좋으며, 상기 BaTiO3는 20-30wt%의 비율로 함유되는 것이 보다 바람직하고, 상기 Al2O3는 30-40wt%의 비율로 함유되는 것이 보다 바람직하다.The dielectric material may be used at a ratio of 20-40 wt% using a nonmagnetic material that is commonly applied. For example, BaTiO 3 , Al 2 O 3 , or the like is preferable. It is preferable that such a dielectric material does not cause deterioration of the characteristics of ferrite when synthesized with the magnetic material, more preferably BaTiO 3 is contained in a ratio of 20-30 wt%, and Al 2 O 3 is 30-40 wt%. It is more preferable to contain in ratio of%.
상기한 바와같이 구성되는 본 발명의 복합재료는 자성체재료와 유전체재료를 합성한 것으로, 투자율을 현저하게 낮춤으로써 투자율의 공진 주파수를 고주파수화하고, 이로인해 인덕턴스의 사용주파수 대역 및 Q가 최대로 되는 주파수 대역을 고주파수로 높이는 것이 가능하다.The composite material of the present invention constituted as described above is composed of a magnetic material and a dielectric material, and by significantly lowering the permeability, the high frequency resonant frequency of permeability is obtained, thereby making the inductance use frequency band and Q maximum. It is possible to increase the frequency band at high frequencies.
즉, 재료의 투자율을 1-20의 영역으로 변화시켜 칩인덕터로 사용할 때 사용주파수 대역을 50-900MHz의 대역으로 높이는 것이 가능하다.In other words, by changing the permeability of the material to the region of 1-20, it is possible to increase the frequency band to 50-900MHz when used as a chip inductor.
이하, 실시예를 통하여 본 발명을 보다 상세히 설명한다.Hereinafter, the present invention will be described in more detail with reference to Examples.
실시예Example
종래의 Ni-Zn-Cu페라이트 자성체를 이용하여 2.0mm×1.2mm×0.9mm 크기의 저주파용 칩인덕터를 적층형으로 구성하였고, Al2O3계 저유전율 재료를 이용하여 동일 크기의 고주파용 칩인덕터를 적층형으로 구성하였다. 또한, Ni-Zn-Cu페라이트 자성체 75wt%와 BaTiO325wt%를 분말형태로 배합한후 물을 가하고, 캐스팅, 인쇄 및 900℃에서 소결하여 상기와 동일한 크기의 칩인덕터를 적층형으로 구성하였다.A low frequency chip inductor with a size of 2.0 mm × 1.2 mm × 0.9 mm was formed using a conventional Ni-Zn-Cu ferrite magnetic material, and a high frequency chip inductor having the same size using Al 2 O 3 based low dielectric constant material. Was constructed in a stacked fashion. Further, 75 wt% of Ni-Zn-Cu ferrite magnetic material and 25 wt% of BaTiO 3 were mixed in powder form, followed by water, casting, printing, and sintering at 900 ° C. to form a chip inductor having the same size as the stacked type.
상기 적층형 칩으로의 구성은 시트(sheet)상에 내부도체로 Ag를 나선형태가 되도록 인쇄하여 도 1과 같은 방법으로 적층하였으며, 적층후, 도 2와 같은 형상으로 칩을 구성하였다.The stacked chip was printed in a spiral manner with Ag as an inner conductor on a sheet, and laminated in the same manner as in FIG. 1. After stacking, the chip was formed in the shape shown in FIG. 2.
얻어진 칩인덕터들을 측정기를 이용하여 주파수별 인덕턴스를 측정하여 그 평균치를, 저주파용은 도 3에, 고주파용은 도 4에, 자성체와 유전체의 복합재료를 사용한 본 발명의 경우는 5에 나타내었다.The inductance for each frequency was measured using a measuring instrument, and the average value of the obtained chip inductors was shown in FIG. 3 for low frequency, in FIG. 4 for high frequency, and in the case of the present invention using a composite material of magnetic material and dielectric.
도 3에서 알 수 있는 바와같이, 저주파용으로 형성된 종래 칩인덕터의 주파수특성은 50MHz이하의 영역에서 사용가능하고, Qmax(품질계수)값이 낮은 주파수 쪽에 치우쳐 있었다.As can be seen from Fig. 3, the frequency characteristics of the conventional chip inductor formed for low frequency can be used in the region of 50 MHz or less, and the Qmax (quality coefficient) value is biased toward the lower frequency.
또한, 도 4에서 알 수 있는 바와같이, 고주파용으로 형성된 종래 칩인덕터의 주파수특성은 900MHz이상의 영역에서 사용가능하고, Qmax값이 높은 주파수 쪽에 치우쳐 있었다.As can be seen from Fig. 4, the frequency characteristics of the conventional chip inductor formed for high frequency are usable in the region of 900 MHz or more, and are biased toward the higher Qmax value.
이에 반하여, 도 5에서 알 수 있는 바와같이, 본 발명에 의해 칩인덕터를 구성한 경우는 50-900MHz영역에서 사용가능하고, Qmax값이 상기 저고주파의 중간 정도의 주파수를 보였다. 또한, 그 인덕턴스가 종래의 자성체만을 이용한 경우와 유전체만을 이용한 경우의 중간값을 나타내었다.On the other hand, as can be seen in Figure 5, when the chip inductor is constructed in accordance with the present invention can be used in the 50-900MHz region, the Qmax value showed a medium frequency of the low frequency. In addition, the inductance is shown as the median value when using only a conventional magnetic material and using only a dielectric material.
상술한 바와같은 본 발명에 의하면, 유전체 재료의 비율을 발명의 범위내에서 조절함으로써, 재료의 투자율을 1-20 영역으로 조절하여 칩 인덕터의 사용주파수 대역을 50-900MHz으로 확대하는 것이 가능하게 되는 효과가 제공된다.According to the present invention as described above, by adjusting the ratio of the dielectric material within the scope of the invention, it is possible to adjust the permeability of the material to the region 1-20 to expand the frequency band of the chip inductor to 50-900MHz The effect is provided.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019980036331A KR20000018655A (en) | 1998-09-03 | 1998-09-03 | Composite material for chip inductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019980036331A KR20000018655A (en) | 1998-09-03 | 1998-09-03 | Composite material for chip inductor |
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| Publication Number | Publication Date |
|---|---|
| KR20000018655A true KR20000018655A (en) | 2000-04-06 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1019980036331A KR20000018655A (en) | 1998-09-03 | 1998-09-03 | Composite material for chip inductor |
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| Country | Link |
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| KR (1) | KR20000018655A (en) |
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1998
- 1998-09-03 KR KR1019980036331A patent/KR20000018655A/en not_active Application Discontinuation
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