KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Austin, AnuSubject: search.filters.subject.3-D lithography

Search Results

Now showing 1 - 1 of 1
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Item,
    Fabrication of Contour Cavity Using Multi-Exposure Lithography for MEMS Capacitive Microphone
    (2018-07-02)
    Jantawong, Jirawat
    ;
    Atthi, Nithi
    ;
    Leepattarapongpan, Chana
    ;
    Jeamsaksiri, Wutthinan
    ;
    Austin, Anu
    This paper presents a novel technique to optimize a capacitive pressure sensor with multi-exposure dose lithography. As part of achieving high signal to noise ratio (SNR) in microphone, a new design was implemented. The new design defies the conventional wisdom of parallel plate theory and implement a concept of contour cavity (backplate) to follows the diaphragm deflection. This 3-dimensional contour cavity (CC) is fabricated by multi-exposure dose lithography with single silicon etching process. The CC structure with different etched depth of 0.65, 1.15, and 1.57 micron were fabricated by multi-exposure dose of 92, 120, and 210 mJ/cm<sup>2</sup>on 5.0 micron thick photoresist and single step etching with CF<inf>4</inf>/O<inf>2</inf>plasma (Si/PR etch selectivity: 1.3). Due to this novel contour cavity design, polysilicon membrane with 0.8 micron thick and a diameter of 930 micron structure produces the capacitance value of 2.88 pF, which is 28.6% higher than that of conventional parallel plate capacitive sensor.