Cobalt (Co) Electrode FBAR Devices Fabricated on Seven-Layered Bragg Reflectors and Their Resonance Characteristics

  • Mai Linh (Communication and Electronics Lab (CEL), Information and Communication and Electronics Lab (CEL)) ;
  • Yim, Mun-Hyuk (CEL, IC) ;
  • Yoon, Gi-Wan (IC) ;
  • Kim, Dong-Hyun (Communication and Electronics Lab (CEL), Information and Communication and Electronics Lab (CEL))
  • Published : 2003.09.01

Abstract

In this paper, cobalt (Co)-electrode FBAR devices fabricated on seven-layered Bragg Reflectors are presented along with their resonance characteristics. ZnO films are used as the resonating material in FBAR devices where the Co electrode is 3000${\AA}$ thick. All processes are preformed in an RF magnetron sputtering system. As a result of characterization, the resonance characteristics are observed to depend strongly on the quality of ZnO film and Bragg Reflectors. In addition, the FBAR devices with W/$SiO_2$ reflectors show good resonance characteristics in term of return loss and quality-factor (Q-factor).

Keywords

film bulk acoustic wave resonator (FBAR);microwave monolithic integrated circuits (MMICs);X-ray diffractometer (XRD);photoresist (PR);Bragg reflector

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