Journal of Advanced Navigation Technology (한국항행학회논문지)

The Korean Navigation Institute (한국항행학회)
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The Effect of Top-electrode Perimeter on the Tunability of Tunable Varactors Based on a BZN/BST/BZN Thin Film

BZN/BST/BZN 박막에 기초한 가변 바렉터의 상부전극 가장자리 길이에 대한 가변성 영향

  • Lee, Young Chul (Department of Electronics, Mokpo National Maritime University) ;
  • Lee, Baek Ju (Department of Materials Science and Engineering, Ajou University) ;
  • Ko, Kyung Hyun (Department of Materials Science and Engineering, Ajou University)
  • 이영철 (목포해양대학교 전자공학과) ;
  • 이백주 (아주대학교 재료공학과) ;
  • 고경현 (아주대학교 재료공학과)
  • Received : 2013.08.30
  • Accepted : 2013.12.30
  • Published : 2013.12.30
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Abstract

This paper has presented that fringing-electric fields enhanced by a finger-type electrode can improve the tunability of the tunable capacitor. Its top electrodes with different area and line width are designed in types of the finger for a long conducting perimeter. The tunable varactors were fabricated on a quartz substrate employing a multi-layer dielectric of a para/ferro/para-electric thin film. Compared to the conventional capacitor, finger-type capacitors are analyzed in terms of effective capacitance and tunablility. Their effective capacitance and tunability of the varactors with the long perimeter increase 24~40 % and 7~12 %, respectively, due to enhanced fringing electric fields from 1 to 2.5 GHz.

본 논문은 핑거 (finger) 형 전극에 의해 증강된 가장자리 전계가 가변 캐패시터의 가변성을 개선시킬 수 있음을 보여주고 있다. 가장자리가 긴 전극을 설계하기 위해 면적과 선폭이 다른 finger 형태의 전극들이 설계되었다. 가변 바렉터들은 quartz 기판위에 para/ferro/para의 가변 다층 유전체 박막을 이용하여 제작되었다. 기존의 일반적인 가변 캐패시터와 비교해서, 핑거형 캐패시터들의 유효 용량와 가변성 특성을 분석하였다. 1~2.5 GHz에서 증강된 가장자리 전계로 인해 긴 가장자리 전극으로 설계된 가변 캐패시터의 유효 용량과 가변성이 각각 24~40 % 그리고 7~12 % 증가하였다.

Keywords

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