o]~ T" .Ruirui Zhang"' %7].'t}"

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FBAR devices employing the ZnO:N films

Eunju Lee* ·Ruirui Zhang*' Giwan Yoon*

"Korea Advanced Institute of Science and Technology

E-mail: gwyoon@ee.kaist.ac.kr

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ABSTRACT

We present a new method for the fabrication of film bulk acoustic wave resonator (FBAR) devices thatexploits the thin piezoelectric ZnO films particularly sputter-deposited in a mixture of N20 and Ar gases asthe reactive and sputtering gases, respectively. Some thermal annealing treatments were performed on theas-deposited ZnO films and also their effects on the resonance characteristics of the FBAR devices wereinvestigated. It was found that with an optimized process, the resonance characteristics of the fabricatedFBAR devices could be further improved.

N-incorporated ZnO films, ZnO:N films, FBAR devices, thermal annealing process

I. Ai E

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Target ZnO, purity: 99.999%Substrate

4-inch, Si waferSubstrate

temperaturenocSubstrate to

target distance10 cmBase chamber

pressure2xlOTorr

Gas composition60% Ar + 40% N,O

Sputteringpressure20 mTorr

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300 W

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