Application of fluorine doped SiO 2 films for temperature compensated SAW devices

S. Matsuda, Motoaki Hara, M. Miura, T. Matsuda, M. Ueda, Y. Satoh, K. Hashimoto

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

    10 Citations (Scopus)

    Abstract

    In our paper, we investigates acoustic properties including temperature coefficient of elasticity (TCE) of fluorine doped silicon oxide (SiOF) films and proposes their application to the temperature compensation of radio frequency (RF) surface acoustic wave (SAW) devices. From the Fourier transform infrared spectroscopy (FT-IR), SiOF films were expected to possess good TCE properties. Then we fabricated a series of SAW devices using the SiOF-overlay/Cu-grating/ LiNbO 3-substrate structure, and their device performances were evaluated. The experiments showed that the temperature coefficient of frequency (TCF) increases with the fluorine content r, as we expected from the FT-IR measurement. This means that the Si-O-Si atomic structure measurable by the FT-IR governs the TCE behavior of SiO 2-based films even when the dopant is added. In comparison with the pure SiO 2 with the film thickness h of 0.3 wavelengths (λ), TCF was improved by 7.7 ppm/°C without deterioration of the effective electromechanical coupling factor K 2 when r=3.8 atomic % and h=0.28λ. The F inclusion did not influence the resonator Q factors obviously when r<8.8 atomic%.

    Original languageEnglish
    Title of host publication2011 IEEE International Ultrasonics Symposium, IUS 2011
    Pages76-78
    Number of pages3
    DOIs
    Publication statusPublished - 2011 Dec 1
    Event2011 IEEE International Ultrasonics Symposium, IUS 2011 - Orlando, FL, United States
    Duration: 2011 Oct 182011 Oct 21

    Publication series

    NameIEEE International Ultrasonics Symposium, IUS
    ISSN (Print)1948-5719
    ISSN (Electronic)1948-5727

    Other

    Other2011 IEEE International Ultrasonics Symposium, IUS 2011
    Country/TerritoryUnited States
    CityOrlando, FL
    Period11/10/1811/10/21

    Keywords

    • FT-IR
    • FWHM
    • SiO
    • TC
    • bond angle
    • peak frequency

    ASJC Scopus subject areas

    • Acoustics and Ultrasonics

    Fingerprint

    Dive into the research topics of 'Application of fluorine doped SiO 2 films for temperature compensated SAW devices'. Together they form a unique fingerprint.

    Cite this