Korean Journal of Crystallography (한국결정학회지)

Korean Crystallographic Association (한국결정학회)
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Control of the Composition of $Ba_{1-x}Sr_ xTiO_3$ Single Crystals

$Ba_{1-x}Sr_ xTiO_3$ 단결정의 조성 제어

  • 노건배 (서울대학교 재료공학부) ;
  • 양상돈 (서울대학교 재료공학부) ;
  • 유상임 (서울대학교 재료공학부)
  • Published : 2003.06.01
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Abstract

(Ba/sub 1-x/Sr/sub x/)TiO₃ (BST, 0.4< x <0.65) single crystals were successfully grown by the TSSG (Top-Seeded Solution Growth) method, using a commercial [100] SrTiO₃ or as-grown [100] BST single crystals as seed crystals. To obtain the BST single crystals with various compositions x, the Ba/sr molar ratios in the solutions were systematically controlled while the Ti ion content among all cations was fixed at 67 mol%. A linear regression curve between their x values and the molar ratios of Sr/(Ba + Sr) in the solutions could be obtained, which in turn could used to select the initial composition to produce BST crystal with an aimed x value. In addition, the isothermal growth was found more effective for obtaining a compositional uniformity than a slow cooling process.

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References

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