Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • Login
    View Item 
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Novel Approaches to Control Surface Reactions in Plasma Etching of Electronic Materials

    Thumbnail
    View/Open
    Li_umd_0117E_20273.pdf (2.460Mb)
    (RESTRICTED ACCESS)
    No. of downloads: 0

    Date
    2019
    Author
    Li, Chen
    Advisor
    Oehrlein, Gottlieb S
    DRUM DOI
    https://doi.org/10.13016/tfnw-v7ob
    Metadata
    Show full item record
    Abstract
    Advanced semiconductor manufacturing requires precise plasma etching control for patterning complex semiconductor device structures. Pattern transfer into dielectric materials is one of the most frequently performed operation and traditionally done using continuous wave (CW) plasma etching processes based on fluorocarbon (FC) chemistries. Such etching methods are facing challenges when the critical dimension (CD) approach 10 nm. Issues include low materials etching selectivity, surface damage, roughness, and poor etching profile control. In this work, various aspects of low temperature plasma-based etching approaches are tailored for optimal plasma etching performance, including novel gaseous precursors for better control of gas phase and surface processes, tailoring the relative importance of radicals and ion bombardment at surface by sequential processes, and a new way to input energy to surfaces to stimulate etching reactions. We systematically studied the impact of molecular structure parameters of hydrofluorocarbon (HFC) precursors on plasma deposition of fluorocarbon (FC) and material etching performance. The HFC chemical composition and molecular structure such as ring structure, C=C, C≡C, C-O, C-H and degree of unsaturation have dramatic impacts on FC surface polymerization and material etching performance. Further, we report a new atomic layer etching (ALE) technique which temporally separates chemical reactant supply to a surface from ion bombardment induced etching. By this ALE method, the ion bombardment energy can be reduced to ensure low substrate damage and extremely high etching selectivity of two materials. Finally, we developed a hollow cathode electron beam etching system to reduce the energy and momentum input on the material surface by utilizing an electron-radical synergy effect. This present work has unveiled highly promising elements of a new roadmap of next generation semiconductor etching approaches and is expected to impact multiple areas of nanoscience and technology, including plasma etching of post-silicon materials. The use of specially selected gaseous precursor chemistry, temporal separation of radical exposure and energy-induced etching, and finally using electron bombardment for activation of surface etching, challenge our current understanding of semiconductor plasma processing and presents an important step forward in terms of the further industrial development of these approaches.
    URI
    http://hdl.handle.net/1903/24956
    Collections
    • Physics Theses and Dissertations
    • UMD Theses and Dissertations

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    Browse

    All of DRUMCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility