KR930002579B1 - Manufacturing method of thick film super conductor - Google Patents
Manufacturing method of thick film super conductor Download PDFInfo
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- KR930002579B1 KR930002579B1 KR1019900011940A KR900011940A KR930002579B1 KR 930002579 B1 KR930002579 B1 KR 930002579B1 KR 1019900011940 A KR1019900011940 A KR 1019900011940A KR 900011940 A KR900011940 A KR 900011940A KR 930002579 B1 KR930002579 B1 KR 930002579B1
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- 238000004519 manufacturing process Methods 0.000 title claims description 17
- 239000002887 superconductor Substances 0.000 title description 13
- 239000000758 substrate Substances 0.000 claims abstract description 31
- 239000000843 powder Substances 0.000 claims abstract description 12
- 239000002270 dispersing agent Substances 0.000 claims abstract description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000011259 mixed solution Substances 0.000 claims abstract description 4
- 239000000243 solution Substances 0.000 claims abstract description 3
- 238000005245 sintering Methods 0.000 claims abstract 3
- 238000007598 dipping method Methods 0.000 claims abstract 2
- 238000001354 calcination Methods 0.000 claims description 5
- 239000008188 pellet Substances 0.000 claims description 4
- 239000002994 raw material Substances 0.000 claims description 4
- 238000010030 laminating Methods 0.000 claims 1
- 238000010298 pulverizing process Methods 0.000 claims 1
- 239000000203 mixture Substances 0.000 abstract description 8
- 238000001035 drying Methods 0.000 abstract description 4
- 238000002156 mixing Methods 0.000 abstract description 4
- 238000010304 firing Methods 0.000 abstract 2
- 239000012254 powdered material Substances 0.000 abstract 2
- 238000005498 polishing Methods 0.000 abstract 1
- 239000004065 semiconductor Substances 0.000 abstract 1
- 239000010408 film Substances 0.000 description 38
- 239000000463 material Substances 0.000 description 24
- 238000000034 method Methods 0.000 description 12
- 238000010438 heat treatment Methods 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 238000007639 printing Methods 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000011368 organic material Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 241000238366 Cephalopoda Species 0.000 description 1
- 229910002367 SrTiO Inorganic materials 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 238000009954 braiding Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 229910052594 sapphire Inorganic materials 0.000 description 1
- 239000010980 sapphire Substances 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 238000010583 slow cooling Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007751 thermal spraying Methods 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
- H10N60/0296—Processes for depositing or forming copper oxide superconductor layers
- H10N60/0324—Processes for depositing or forming copper oxide superconductor layers from a solution
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/80—Constructional details
- H10N60/85—Superconducting active materials
- H10N60/855—Ceramic superconductors
- H10N60/857—Ceramic superconductors comprising copper oxide
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Abstract
Description
제1도는 전이온도(Tc)측정 그래프1 is a graph of transition temperature (Tc) measurement
제2도는 임계전류밀도(Jc)측정 그래프2 is a graph of the critical current density (Jc) measurement
본 발명은 후막초전도체에 관한 것으로, 보다 상세하게는 고전이온도화, 고전류밀도화 및 고임계자장화에 적당한 산화물계 후막초전도체와 그 제조방법에 관한 것이다. 실장기판배선, 직류 SQUID, 자기실드재료등에는 박막 또는 후막초전도체등이 이용되고 있으나, 후막은 박막에 비하여 제조공정이 간단하고 제조비용이 낮아 널리 이용되고 있다. 산화물 후막초전도체의 제조는 기판의 제조, 후막제조, 후막화 공정등으로 이루어지는 것으로서, 기판재료를 선정하여 기판을 만든 후 기간위에 후막재료를 입히고 열처리를 행한다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to thick film superconductors, and more particularly, to oxide thick film superconductors suitable for high temperature conversion, high current density, and high critical magnetic field and a method of manufacturing the same. Thin film or thick film superconductors are used for mounting substrate wiring, DC SQUID, magnetic shielding materials, etc. However, thick films are widely used due to their simpler manufacturing process and lower manufacturing cost than thin films. The manufacture of the oxide thick film superconductor consists of a substrate production, a thick film production, a thick film formation process, and the like. After the substrate material is selected and the substrate is made, a thick film material is coated over a period of time and heat-treated.
종래의 산화물제 초전도체 제조에 있어서 기판재료는 산화물 초전도체 후막과 반응하지 않으며 후막과 강한 결합을 이룰 수 있는 것으로 선정되는데 일반적으로 MgO, SrTiO3, 사파이어, Al2O3등이 이용되고 있다.In conventional oxide superconductor production, the substrate material is selected to not react with the oxide superconductor thick film and to form a strong bond with the thick film. MgO, SrTiO 3 , sapphire, and Al 2 O 3 are generally used.
후막제조방법으로서는 후막인쇄법, 닥터브레이드법, 용사법, 프라즈마스프레이법등이 있으나, 가장널리 이용되고 있는 후막인쇄법에 대하여 설명한다.As a thick film manufacturing method, there are a thick film printing method, a doctor braiding method, a thermal spraying method, a plasma spray method and the like, but the most widely used thick film printing method will be described.
후막인쇄법은 산화물계 초전도체를 선정 분쇄하여 분말상태로 만든 후 이를 분산제, 솔벤트, 결합제등과 혼합하여 페이스트상으로 한다.In the thick film printing method, the oxide-based superconductor is selected and pulverized into a powder state, and then mixed with a dispersant, a solvent, and a binder to form a paste.
이런 페이스트상을 실크스크린장치를 이용하여 기판위에 프린팅한후 열처리하여 페이스트상에 포함되어있는 분산제, 솔벤트등과 같은 각종 유기물등을 효율적으로 완전히 제거하여야 한다.This paste phase is printed on a substrate using a silk screen device and then heat treated to efficiently remove various organic substances such as dispersants, solvents, and the like contained in the paste.
이 열처리과정은 후막의 특성결점에 중요한 역할을 하는데 많은 기술과 경험의 축적을 요한다.This heat treatment process plays an important role in the characteristic defect of thick film and requires a lot of skill and experience.
또한 종전의 후막재료로서는 산화물 초전도 체인 YBa2Cu3O5-x 를 사용하여 상기와 같은 방법으로 기판에 입힌 후 열처리하고 있으나, 이 경우는 상기와 같은 기판재료와 후막재료 는 격자 상수 및 열팽창계수등의 차이에 따라 후막재료인 YBa2Cu2O5-x의 조성이 깨어지거나 후막에 균열이 발생하며, 또한 기판과 후막과의 점착(adhesion)이 제대로 이루어지지 않는등 그 특성이 저하되어 초전도성이 상실되거나 저하된다.In addition, as a conventional thick film material, an oxide superconducting chain YBa 2 Cu 3 O 5 -x is applied to the substrate in the same manner as described above, and then heat-treated. In this case, the substrate material and the thick film material are lattice constants and thermal expansion coefficients. According to the difference, the composition of YBa 2 Cu 2 O 5 -x, which is a thick film material, is cracked or cracks occur in the thick film, and its properties are deteriorated, such as poor adhesion between the substrate and the thick film. This is lost or degraded.
이상에서와 같은 종래기술에서는 후막재료 자체가 산화물 초전도체이므로 이를 미리 제조하여야 하는데 이때 많은 기술과 시간, 비용이 소요되며, 페이스트화하기 위하여 각종 유기물등을 혼합하므로서 후막이 오염될 가능성이 있으며 열처리에서 유기물등의 제거된 후는 후막의 재질이 엉성해진다.In the prior art as described above, since the thick film material itself is an oxide superconductor, it has to be manufactured in advance. In this case, a lot of technology, time, and cost are required. There is a possibility that the thick film may be contaminated by mixing various organic materials to paste the organic material in the heat treatment. After the back is removed, the material of the thick film becomes loose.
또한 상기와같은 격자상수 및 열팽창계수에 따른 단점을 없애기 위하여 적당한 기판재료의 선정의 용이치않는등의 문제점이 있다.In addition, there is a problem in that it is not easy to select a suitable substrate material in order to eliminate the disadvantages caused by the lattice constant and thermal expansion coefficient as described above.
본 발명은 종래와 같은 문제점을 해결할 수 있는 새로운 후막 초전도체와 그 제조방법을 제공코저 하는것으로서, 이하 본 발명을 설명하면 다음과 같다.The present invention is to provide a new thick film superconductor and a method for manufacturing the same, which can solve the problems as described above.
본 발명은 기판의 제조, 후막재료의 제조, 후막화공정으로 이루어진다.This invention consists of manufacture of a board | substrate, manufacture of a thick film material, and thickening process.
먼저 기판의 재료는 Y2BaCuO5소결체인데 그 제조공정은, (1)Y2O3: BaCo3: Cuo=1 : 1 : 1몰(mole)비로 한 분말을 분산제를 사용하여 습식 혼합한다.First of all, the material of the substrate is a Y 2 BaCuO 5 sintered body. In the manufacturing process, (1) Y 2 O 3 : BaCo 3 : Cuo = 1: 1: 1 mole ratio of the powder is wet mixed using a dispersant.
(2) 습식 혼합한 것을 건조하여 850℃-900℃에서 15-30시간 1차 하소하고,(2) The wet mixture was dried and first calcined at 850 ° C.-900 ° C. for 15-30 hours,
(3) 1차 하소된 분말을 Pellet 상으로 하여 900℃-1000℃에서 15-30시간 2차 하소한다.(3) The first calcined powder was calcined on a pellet for 15-30 hours at 900 ° C-1000 ° C.
(4) 2차 하소한 것을 분쇄한 후 다시 Pellet 모양으로 하여 950℃-1250℃에서 3-10시간 동안 최종 소결하여 Y2BaCuO5로 된 소결체 기판을 만든다.(4) After the second calcined thing was pulverized, it was made into pellet shape again and finally sintered at 950 ° C-1250 ° C for 3-10 hours to form a sintered body substrate made of Y 2 BaCuO 5 .
(5) 이를 적당한 크기로 절단 후 연마(polishing)한다. 이와같은 기판재료의 제조에서 원료배합비를 1 : 1 : 1 :의 몰비로 하였으나 이는 Y2BaCuO5형성을 위한 하나의 배합예를 제시한 것으로서 이에 한정하지 않는다. 하소열처리 조건을 단계별로 선정한 것은 안정된 분위기 하에서 탄소(C)등의 불순물을 제거함과 동시에 단일상을 조성하기 위한 것으며, Y2BaCuO5는 950℃에서 상(Phase)이 형성되기 시작하여 약 1260℃까지의 안정함으로 이와같은 조건을 택하였다.(5) It is cut to size and polished. In the preparation of such a substrate material, the mixing ratio of the raw materials is set at a molar ratio of 1: 1: 1: 1, but this is one example of formulation for forming Y 2 BaCuO 5 and is not limited thereto. The calcination heat treatment step was selected step by step to remove impurities such as carbon (C) in a stable atmosphere and to form a single phase. Y 2 BaCuO 5 began to form phases at 950 ° C. Such conditions were taken with stability to < RTI ID = 0.0 >
후막재료는 Ba2Cu5O8으로 된 소결체를 사용하는데 이에대한 제조공정으로서는.The thick film material is a sintered body made of Ba 2 Cu 5 O 8 .
(1) BaO : Cuo=3 : 5의 몰(mole)비로 한 분말을 분산제를 사용하여 습식 혼합한다.(1) A powder having a molar ratio of BaO: Cuo = 3: 5 is wet mixed using a dispersant.
(2) 이를 건조후 750℃-850℃에서 15-30시간 1차 하소한다.(2) It is first calcined at 750 ℃ -850 ℃ for 15-30 hours after drying.
(3) 1차 하소된 분말을 Pellet 모양으로 하여 800-900℃에서 15-30시간 2차 하소한다.(3) The first calcined powder is pelletized to form secondary calcining at 800-900 ° C. for 15-30 hours.
(4) 2차 하소한 것을 분쇄한 후 다시 적당한 크기의 Pellet모양으로 하여 850-950℃에서 3-10시간 최종소결한다. 그후 잘게 분쇄하여 일정한 크기의 분말을 골라 Ba3Cu5O8로 된 분말을 후막재료로 사용한다.(4) After the second calcined thing is pulverized, form a pellet of appropriate size and finally sinter 3-10 hours at 850-950 ℃. After that, finely pulverized, a powder of a certain size is selected, and a powder of Ba 3 Cu 5 O 8 is used as a thick film material.
상기화같은 후막재료의 제조에서 원료배합을 3 : 5몰비로 하였으나 이는 Ba2Cu5O8형성을 위한 하나의 배합 예를 제시한 것으로서 이에 한정하지 않는다.In the preparation of the thick film material as described above, the raw material mixture was 3: 5 molar ratio, but this is one example of the formulation for Ba 2 Cu 5 O 8 formation and is not limited thereto.
하소조건을 단계별로 선정한 것은 기판재료, 제조시의 이유에 대동소이하며, Ba3Cu5O8은 약 800℃에서 상(Phase)이 형성되어 약 950℃까지의 안정함으로 이와같은 조건을 택하였다.The selection of the calcination conditions step by step is very similar to the reason for the substrate material and the manufacturing process, and Ba 3 Cu 5 O 8 was chosen as such that the phase was formed at about 800 ℃ and stable up to about 950 ℃. .
이상에서와 같은 기판 및 후막제조에서의 조건들은 기판의 강도, 분말화용이성, 안정성, 경제성등을 고려하여 선정한다.The conditions in the substrate and thick film production as described above are selected in consideration of the strength of the substrate, easy to powder, stability, economical and the like.
다음은 기판에 후막재료를 입힌 후 열처리하는 후막화공정에 대하여 설명한다.Next, a thick film forming process of coating a thick film material on a substrate and then performing heat treatment will be described.
먼저, 에타놀 : 후막분말재료 : 분산제=500 : 200 : 1의 무게비로 한 혼합용액을 만들어 이용액에 Y2BaCuO5로 된 기판을 넣었다가 꺼내 상기 조성용액이 기판에 적층되도록 한 후 이를 건조시켜 열처리한다.First, a mixed solution having a weight ratio of ethanol: thick film powder material: dispersant = 500: 200: 1 was added to the substrate using Y 2 BaCuO 5 , and then the composition solution was laminated on the substrate, followed by drying. do.
열처리는 850-950℃에서 3-10시간 한 후 서냉시킨다. 이렇게 열처리함에 따라 기판재료인 Y2BaCuO5와 후막 재료인 Ba2Cu5O8사이에서 Y, Ba, Cu등의 원소는 그 농도차이에 의한 액상-고상포정반응(liguid-solid peritectic reaction)인 확산을 통해 YBa2Cu3O5-x의 산화물 후막초전도체가 얻어진다.The heat treatment is performed at 850-950 ° C. for 3-10 hours, followed by slow cooling. As a result of the heat treatment, between Y 2 BaCuO 5 , which is a substrate material, and Ba 2 Cu 5 O 8, which is a thick film material, elements such as Y, Ba, and Cu are liquid-solid peritectic reactions due to the concentration difference. Through diffusion, an oxide thick film superconductor of YBa 2 Cu 3 O 5 -x is obtained.
즉, Y2BaCuO5+Ba3Cu5O8→YBa2Cu3O5-x와 같은 확산반응에 따라 본발명 이 제조된다.That is, the present invention is prepared according to a diffusion reaction such as Y 2 BaCuO 5 + Ba 3 Cu 5 O 8 → YBa 2 Cu 3 O 5 -x.
본 발명에 의한 기술은 기판재료와 후막재료 모두 격자상수 및 열팽창계수가 거의 비숫하고 상기 반응을 통하여 이루어지므로 종전기술과 같은 문제가 발생되지 않을 뿐 아니라 기판과 후막사이에 상기반응에 의하 flux가 형성되어 점착강도를 더욱 좋게 한다.In the technique according to the present invention, since both the lattice constant and the coefficient of thermal expansion of the substrate material and the thick film material are almost same and are made through the reaction, the same problem as the conventional technology does not occur, and the flux is formed between the substrate and the thick film by the reaction. To improve adhesion strength.
또한 종래의 경우는 스크린 프린팅을 위해 Paste를 제조하는 공정을 Paste내에 바이더, 플라스틱 사이저, Glass frit등과 같은 첨가물이 함유되어 있어 후막산화물 초전도체를 제조하였을 때는 완전히 유기물등이 없어지지 않거나 기공을 남김으로서 그 특성을 저하시킬 우려가 있었으나, 본 발명에 의한 것은 대부분 상온중에서 휘발되는 에타놀을 사용하였으며, Glass frit을 사용하지 않아도 점착이 잘이루어진다.In addition, in the conventional case, the paste manufacturing process for screen printing includes additives such as a binder, plastic sizer, glass frit, etc. in the paste, and when the thick oxide oxide superconductor is manufactured, organic matters do not disappear or leave pores. Although there was a risk of deterioration of properties, most of the present invention used ethanol volatilized at room temperature, and adhesion is achieved even without using glass frit.
이상에서와같이 본 발명에 의하여 제조된 후막초전도체는 기판의 밀도가 5.1g/Cm3으로 이론밀도의 약 80%이고 후막의 두께는 농도나 열처리조건에 따라 10μm-50μm을 얻을 수 있었다.As described above, the thick film superconductor manufactured according to the present invention had a substrate density of 5.1 g / Cm 3 , about 80% of the theoretical density, and a thick film thickness of 10 μm to 50 μm, depending on the concentration and heat treatment conditions.
제1도와 제2도는 910℃에서 6시간 열처리한 시편의 물성치를 나타낸 그래프로서, 제1도에서 전이온도
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019900011940A KR930002579B1 (en) | 1990-08-03 | 1990-08-03 | Manufacturing method of thick film super conductor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019900011940A KR930002579B1 (en) | 1990-08-03 | 1990-08-03 | Manufacturing method of thick film super conductor |
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| Publication Number | Publication Date |
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| KR920005398A KR920005398A (en) | 1992-03-28 |
| KR930002579B1 true KR930002579B1 (en) | 1993-04-03 |
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| Application Number | Title | Priority Date | Filing Date |
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| KR1019900011940A KR930002579B1 (en) | 1990-08-03 | 1990-08-03 | Manufacturing method of thick film super conductor |
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| KR (1) | KR930002579B1 (en) |
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1990
- 1990-08-03 KR KR1019900011940A patent/KR930002579B1/en not_active IP Right Cessation
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| KR920005398A (en) | 1992-03-28 |
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