Fabrication of SAW filter using PZT ceramics

PZT압전세라믹을 이용한 SAW필터의 제작

  • 정연호 (성균관대학교 전기공학과) ;
  • 송준태 (성균관대학교 전기공학과)
  • Published : 1997.01.01

Abstract

SAW filter has been used in mobile communication device, bandpass filter and resonator for merits )f miniaturization and high reliability. Materials for substrate mainly used single crystal such as LiNbO$_{3}$, LiTaO$_{3}$, ZnO. In this study, it was attempted that LiNbO$_{3}$ was substituted for piezoelectric ceramics(PZT4, PZT5A and PZT8) which had simple fabrication process because fabrication of crystal is difficult and it's cost is high. SAW filters were fabricated by the photolithography on piezoelectric ceramics substrates in order to compare their characteristics with LiNbO$_{3}$'s. The experimental value of center frequency was compared with theoretical one. The average difference of center frequency was 3.7%. PZT8 showed the best bandwidth properties among them. It is considered that PZT8 has higher mechanical quality factor and propagation velocity than others.

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