The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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Fabrication of AIN-based FBAR Devices by Using a Novel Process and Characterization of Their Frequency Response Characteristics in terms of Various Electrode Metals

새로운 공정을 이용한 AIN 체적 탄성파 소자의 제작 및 다양한 금속 전극막에 따른 주파수 응답 특성 분석

  • 김보현 (한양대학 전자전기제어계측공학과) ;
  • 박창균 (한양대학 전자전기제어계측공학과) ;
  • 박진석 (한양대 전자컴퓨터공학부)
  • Published : 2007.05.01
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Abstract

AIN-based film bulk acoustic resonator (FBAR) devices which adopt a membrane-type configuration such as Mo/AIN/bottom-metal/Si are fabricated by employing a novel process. The proposed resonator structure does not require any supporting layer above the substrate, which leads to the reduction in energy loss of the resonators. For all the FBAR devices, the frequency response characteristics are measured and the device parameters, such as return loss and input impedance, are extracted from the frequency responses, and analyzed in terms of the various metals such as Al. Cu, Mo, W used in the bottom-electrode. The mass-loading effect caused by the used bottom-electrode metals is found to be the main reason for the difference revealed in the measured characteristics of the fabricated FBAH devices. The results obtained in this study also show that the degree of match in lattice constant and thermal expansion coefficient hetween piezoelectric layers and electrode metals is crucial to determine the device performance of FEAR.

Keywords

References

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