Progress in Superconductivity and Cryogenics (한국초전도ㆍ저온공학회논문지)

The Korean Society of Superconductivity and Cryogenics (한국초전도저온학회)
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Effect of annealing time on MOD-YBCO films at reduced total pressure

저압공정을 이용한 MOD-YBCO 박막의 열처리 시간 효과

  • 정국채 (한국기계연구원 신기능재료연구본부) ;
  • 유재무 (한국기계연구원 신기능재료연구본부) ;
  • 고재웅 (한국기계연구원 신기능재료연구본부) ;
  • 김영국 (한국기계연구원 신기능재료연구본부)
  • Published : 2006.09.01
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Abstract

The effect of annealing time in Metal Organic Deposition(MOD) method was investigated at reduced total pressure. As the total annealing pressure was reduced, the growth rate of YBCO films increased from 0.14nm/sec at atmospheric pressure to 4.2nm/sec at 1 Torr. For the total pres sure of 700, 500, 300, 100, and 1 Torr, the optimal annealing times of 60, 40, 20, 10, 2minutes were found in our experimental conditions. When the an nealing time was short, poor crystallinity or un-reacted phase was obtained. Also, the degradation of YBCO films occurred when exposed longer to the humid ambient at the high annealing temperature. The reduced pressure was found effective to in crease the growth rate and to control the pore size of the YBCO films in MOD method. A fast growth of MOD-YBCO films was realized with high critical current density over $1MA/cm^2$ using reduced pressure annealing. Large pores, usually observed at atmospheric pressure in MOD method, disappeared and also, the number of pores was reduced.

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References

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