• Login
    View Item 
    •   DSpace@RPI Home
    • Rensselaer Libraries
    • RPI Theses Online (Complete)
    • View Item
    •   DSpace@RPI Home
    • Rensselaer Libraries
    • RPI Theses Online (Complete)
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Quantitative temperature sensing and thin film thermal conductivity measurement by non-contact scanning thermal microscopy

    Author
    Zhang, Yun
    View/Open
    Zhang_rpi_0185E_11778.pdf (3.231Mb)
    Other Contributors
    Borca-Tasçiuc, Theodorian; Borca-Tasçiuc, Diana-Andra; Koratkar, Nikhil; Plawsky, Joel L., 1957-;
    Date Issued
    2020-08
    Subject
    Mechanical engineering
    Degree
    PhD;
    Terms of Use
    This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute (RPI), Troy, NY. Copyright of original work retained by author.;
    Metadata
    Show full item record
    URI
    https://hdl.handle.net/20.500.13015/6168
    Abstract
    Scanning Thermal Microscopy (SThM) is a powerful technique that can measure samples’ thermal conductivity, temperature, Seebeck coefficient, and topography at the same time with excellent spatial resolution and sensitivity. It has a lot of potential applications in material science, nanoelectronics design, and even biological field. The current state-of-the-art SThM focuses on the contact mode that has inaccuracy due to surface artifacts and suffers from probe damage. Therefore, this thesis reports the investigation on the development, validation, and application of a quantitative non-contact SThM under ambient conditions for temperature sensing and high thermal conductivity 2D sample characterization. This thesis is divided into six chapters. The first chapter introduced the history and background of the SThM development and states the motivation of this thesis. The second chapter describes the experimental, numerical, and analytical methods for a proof-of-concept demonstration. The experiments involve a passive probe that measures sample temperature and an active that measures sample thermal conductivity in the diffusive and the transition regimes. The analytical models of the active and passive probes and a multilayer sample are also introduced. A cutting procedure forces the 3-Dimensional Finite Element Model (3DFEM) to take the transition heat transfer between the probe and the sample into account and a useful correlation of the probe-sample air gap thermal resistance is developed by the validated 3DFEM. Then the discussion continues to the calibration of the thermal exchange parameters, which are important for the quantitative and accurate temperature and thermal conductivity results. The probe-sample air gap thermal resistance correlation together with the analytical models forms the basis of the active and passive calibration techniques for temperature sensing. For film thermal conductivity measurement, the thermal exchange radii are found by fitting the 3DFEM heat flux profile on the sample surface. Chapter 3 reports the validated results and demonstrates the experimental setup having a 700 nm spatial resolution and 0.01 K temperature resolution of the temperature sensing and a film thermal conductivity of up to ~240 W/(m·K) and down to 0.2 W/(m·K) with thickness from 46.6 nm to 240 nm can be measured with the setup. Extended on the validated 3DFEM, Chapter 4 discusses the definitions and methods to evaluate the sensitivity and spatial resolution of commercial thermoresistive probes. The sensitivity and spatial resolution of the Wollaston wire probe were also documented in detail when measuring film thermal conductivity. Generally, a probe with a more focused heat source will have a higher spatial resolution and a probe with a more spreading heat source will have a better sensitivity. The existence of the cantilever may significantly affect the overall performance. The DS probe was found to have the best sensitivity and the Nanowire probe had the finest spatial resolution when they are measuring thermal conductivities. The Wollaston wire probe had the highest spatial resolution and the DS probe is most sensitive to the sample temperature change. The investigation of the probe performances inspires the study of modified probe geometry for the KNT and the Wollaston wire probe and the optimized Wollaston wire probe has a 2.4 μm diameter. Chapter 5 summarizes this thesis and highlights important conclusions. The unaddressed challenges of parasite effect of temperature sensing and further probe optimization and fabrication are emphasized as guidance for future research.;
    Description
    August 2020; School of Engineering
    Department
    Dept. of Mechanical, Aerospace, and Nuclear Engineering;
    Publisher
    Rensselaer Polytechnic Institute, Troy, NY
    Relationships
    Rensselaer Theses and Dissertations Online Collection;
    Access
    Restricted to current Rensselaer faculty, staff and students in accordance with the Rensselaer Standard license. Access inquiries may be directed to the Rensselaer Libraries.;
    Collections
    • RPI Theses Online (Complete)

    Browse

    All of DSpace@RPICommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Login

    DSpace software copyright © 2002-2023  DuraSpace
    Contact Us | Send Feedback
    DSpace Express is a service operated by 
    Atmire NV