The Journal of Korean Institute of Electromagnetic Engineering and Science (한국전자파학회논문지)

The Korean Institute of Electromagnetic Engineering and Science (한국전자파학회)
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BST Thin Film Variable Capacitor with High Tunability on Silicon Wafer

가변 특성이 우수한 실리콘 기판을 사용한 BST 박막형 가변 커패시터

  • Kim Ki-Byoung (RFIC Research and Education Center, Kwangwoon University) ;
  • Yun Tae-Soon (RFIC Research and Education Center, Kwangwoon University) ;
  • Lee Jong-Chul (RFIC Research and Education Center, Kwangwoon University) ;
  • Kim Ran-Young (Dept. of Material Sci. and Eng, KAIST) ;
  • Kim Hyun-Suk (Dept. of Material Sci. and Eng, KAIST) ;
  • Kim Ho-Gi (Dept. of Material Sci. and Eng, KAIST)
  • 김기병 (광운대학교 ITRC RFIC 연구센터) ;
  • 윤태순 (광운대학교 ITRC RFIC 연구센터) ;
  • 이종철 (광운대학교 ITRC RFIC 연구센터) ;
  • 김란영 (한국과학기술원 재료공학과) ;
  • 김현석 (한국과학기술원 재료공학과) ;
  • 김호기 (한국과학기술원 재료공학과)
  • Published : 2005.03.01
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Abstract

In this paper, BaSrTiO$_{3}$(BST) thin film tunable interdigital capacitor using low cost silicon substrate instead of expensive single-crystalline substrate is presented. The tunable capacitor in which BST thin film is deposited by PLD has operation frequency and applied bias up to 4 GHz and 50 V, respectively. The maximum tunability in capacitance is found to be 30$\%$, for an applied field of 5 kV/cm at a bias of 50 V. Therefore, it has been shown that the BST microwave tunable capacitor can be integrated onto Si substrate.

본 논문에서는 고가의 단결정 기판 대신에 저가의 실리콘 기판을 이용한 인터디지탈 구조의BaSrTiO$_{3}$(BST) 박막 가변 커패시터를 제안하였다. 저가의 실리콘 기판 위의 BST 박막은 PLD 장비를 이용하여 증착하였으며, 제작된 가변 커패시터는 4 GHz까지 측정되었다. 또한 최대 인가 전압은 50 V이며, 5 kV/cm 조건에서 약 30$\%$ 정도의 가변율을 얻는다. 저가의 실리콘 기판 위에 BST 박막을 증착, 커패시터를 구현함으로써 BST 박막을 이용한 가변 소자들을 집적화할 수 있는 가능성을 보였다.

Keywords

References

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