Karl Hobart

Naval Research Laboratory
  • Exploring the capability of Hyperspectral Electroluminescence for process monitoring in vertical GaN devices

    Karl Hobart, Naval Research Laboratory
    Mona Ebrish, NRC Postdoctoral Fellow Residing at NRL
    Travis Anderson, Naval Research Laboratory
    James Gallagher, ASEE Postdoctoral Fellow Residing at NRL
    Joseph Spencer, Virginia Tech
    Jennifer Hite, Naval Research Laboratory
    Michael Mastro, Naval Research Laboratory

    GaN is a promising material for more efficient high frequency and high voltage power switching. However, GaN still is not the common material for power electronics due to immature substrate, homoepitaxial growth, and processing technology. Electroluminescence is a promising method to predict failure points due to high field stress, which can assist in the separation of inherent defects stemming from substrate quality, and from process-induced defects as well as identify problems related to proper edge termination design. In this work, we compare the Electroluminescence signatures of devices on inhomogeneous substrates to DC I-V behavior to demonstrate the utility of the technique for process monitoring.

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  • 13.1 High Aspect Ratio Vias in Silicon Carbide Etched by Inductively-Coupled Plasma

    Marko Tadjer, Naval Research Laboratory
    Lunet Luna, U.S. Naval Research Laboratory
    Eugene Imhoff, Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Fritz Kub, Naval Research Laboratory
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  • 16.3 Evaluation of GaN Device Structures on 150 mm GaN on Engineered Substrates

    Karl Hobart, Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Andrew Koehler, Naval Research Laboratory
    Anindya Nath, George Mason University
    Jennifer Hite, U.S. Naval Research Laboratory
    N. Mahadik, U.S. Naval Research Laboratory
    Fritz Kub, Naval Research Laboratory
    Ozgur Aktas, Qromis, Inc.
    Vladimir Odnoblyudov, QROMIS, Inc.
    Cem Basceri, QROMIS, Inc.
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  • 18.2 Engineering PECVD SiN Passivation Layers to Enable AlGaN/GaN HEMTs with Low Leakage, Low Current Collapse and High Breakdown Voltage

    Andrew Koehler, Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Marko Tadjer, Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Fritz Kub, Naval Research Laboratory
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  • 18.3 Threshold Voltage Control by Tuning Charge in ZrO2 Gate Dielectrics for Normally-off AlGaN/GaN MOS-HEMTs

    Travis Anderson, Naval Research Laboratory
    Virginia Wheeler, U.S. Naval Research Laboratory
    David Shahin, University of Maryland
    Marko Tadjer, Naval Research Laboratory
    Lunet Luna, U.S. Naval Research Laboratory
    Andrew Koehler, Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Francis Kub, U.S. Naval Research Laboratory
    Charles Eddy, US Naval Research Laboratory
    Jr., Naval Research Laboratory
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  • 20.5 Characterization of ALD High-k Dielectrics in GaN and Ga2O3 Metal-Oxide-Semiconductor Systems

    David Shahin, University of Maryland
    Travis Anderson, Naval Research Laboratory
    Virginia Wheeler, U.S. Naval Research Laboratory
    Marko Tadjer, Naval Research Laboratory
    Lunet Luna, U.S. Naval Research Laboratory
    Andrew Koehler, Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Charles Eddy, US Naval Research Laboratory
    Jr., Naval Research Laboratory
    Fritz Kub, Naval Research Laboratory
    Aris Christou, University of Maryland-College Park
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  • 5.3 Influence of Substrate Removal on the Electrothermal Characteristics of AlGaN/GaN Membrane High Electron Mobility Transistors

    Marko Tadjer, Naval Research Laboratory
    Peter Raad, TMX Scientific and Southern Methodist University
    Tatyana Feygelson, Naval Research Laboratory
    Andrew Koehler, Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Bradford Pate, Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Fritz Kub, Naval Research Laboratory
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  • 9.1 Improvements in the Annealing of Ion Implanted III-Nitride Materials and Related Devices

    Jordan Greenlee, NRC Postdoctoral Fellow Residing at the Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Boris Feigelson, Naval Research Laboratory
    Jennifer Hite, U.S. Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Francis Kub, U.S. Naval Research Laboratory
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  • 10b.4 Reliability Assessment of Thermally-Stable Gate Materials for AlGaN/GaN HEMTs

    David Shahin, University of Maryland
    Travis Anderson, Naval Research Laboratory
    Jordan Greenlee, NRC Postdoctoral Fellow Residing at the Naval Research Laboratory
    Andrew Koehler, Naval Research Laboratory
    Virginia Wheeler, U.S. Naval Research Laboratory
    Marko Tadjer, Naval Research Laboratory
    Tatyana Feygelson, Naval Research Laboratory
    Bradford Pate, Naval Research Laboratory
    Jennifer Hite, U.S. Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Charles Eddy, US Naval Research Laboratory
    Jr., Naval Research Laboratory
    Francis Kub, U.S. Naval Research Laboratory
    Aris Christou, University of Maryland-College Park
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  • 11.2 Effect of Surface Passivation on Current Collapse of Proton-Irradiated AlGaN/GaN HEMTs

    Andrew Koehler, Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Marko Tadjer, Naval Research Laboratory
    Bradley Weaver, U.S. Naval Research Laboratory
    Jordan Greenlee, NRC Postdoctoral Fellow Residing at the Naval Research Laboratory
    David Shahin, University of Maryland
    Karl Hobart, Naval Research Laboratory
    Francis Kub, U.S. Naval Research Laboratory
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  • 11.5 Optimization of AlGaN/GaN HEMT SiN Passivation by Mixed Frequency PECVD

    Marko Tadjer, Naval Research Laboratory
    Andrew Koehler, Naval Research Laboratory
    Charles Eddy, US Naval Research Laboratory
    Jr., Naval Research Laboratory
    Travis Anderson, Naval Research Laboratory
    Karl Hobart, Naval Research Laboratory
    Fritz Kub, Naval Research Laboratory
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