Fabrication of surface micromachined ain piezoelectric microstructures and its potential apllication to rf resonators

S. Saravanan, S. Saravanan, Johan W. Berenschot, Gijsbertus J.M. Krijnen, Michael Curt Elwenspoek

    Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review

    25 Citations (Scopus)
    37 Downloads (Pure)


    We report on a novel microfabrication method to fabricate aluminum nitride (AlN) piezoelectric microstructures down to 2 microns size by a surface micromachining process. Highly c-axis oriented AlN thin films are deposited between thin Cr electrodes on polysilicon structural layers by rf reactive sputtering. The top Cr layer is used both as a mask to etch the AlN thin films and as an electrode to actuate the AlN piezoelectric layer. The AlN layer is patterned anisotropically by wet etching using a TMAH (25%) solution. This multilayer stack uses silicon-di-oxide as a sacrificial layer to make free-standing structures. One-port scattering paramenter measurement using a network analyzer show a resonant frequency of 1.781 GHz on a clamped-clamped beam suspended structure. The effective electromechanical coupling factor is calculated as 2.4 % and the measured bandwidth is 13.5 MHz for one such a doubly clamped beam (990x30) μm2.
    Original languageUndefined
    Title of host publicationSymposium on Design, Test, Integration, and Packaging of MEMS/MOEMS (DTIP)
    Place of PublicationGrenoble
    PublisherDTIP of MEMS & MOEMS
    Number of pages5
    ISBN (Print)2-84813-057-1
    Publication statusPublished - 2005
    Event2005 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS, DTIP 2005 - Montreux, Switzerland
    Duration: 1 Jun 20053 Jun 2005

    Publication series

    Number01-03 June


    Conference2005 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS, DTIP 2005
    Abbreviated titleDTIP


    • EWI-10356
    • METIS-224195
    • IR-52576

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