Characterization and reliability of vertical n-type gallium nitride Schottky contacts

Download
Author
Gardner, Michael L.
Date
2016-09Advisor
Weatherford, Todd R.
Second Reader
Porter, Matthew A.
Metadata
Show full item recordAbstract
Silicon- and silicon carbide-based power devices have dominated the power electronics industry. For many emerging high-current and high-power applications, vertical transport gallium nitride (GaN)-based devices are more desirable. In this study, a series of reduced-defect, vertical n-type GaN Schottky contacts were fabricated and subjected to high-current density accelerated lifetime tests to understand the physics of contact degradation and compare the reliability of different metallization types and process cleans. Tested Schottky metals included molybdenum, molybdenum-gold, and chromium-gold. Process cleans compared were a piranha etch and a hydrofluoric acid etch. Pre-stress electrical characterization confirmed functioning Schottky contacts and determined device electrical performance parameters. Using a stress-measure- stress system, we obtained results of high-current density accelerated lifetime testing of 170 hours at current densities of 2.3 kAcm-² that showed both catastrophic and non-catastrophic failures across all metallization types and process cleans. While comparative analysis showed that molybdenum was the most reliable, identified experimental testing and non-ideal fabrication issues limited the conclusivity of the results. The identified constraints and initial comparative results serve to inform future Schottky contact structural design and fabrication for future optimized testing
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.Collections
Related items
Showing items related by title, author, creator and subject.
-
Implementation and Design of a Novel Student Developed Modular HTOL/HTRB System Using Thermoelectric Control
O’Neal, Nathaniel J.; Porter, Matthew A.; Martino, Christopher Adrian (American Society for Engineering Education, 2021);Addressing reliability issues is critical to the successful design and implementation of new semiconductor material systems proposed for next generation power electronic devices. For military systems, reliability is central ... -
Stress and Reliance Decisions [video]
McGuire, Mollie (2018-04-18);The focus of the current study is to examine reliance on automation using a decision making framework. Specifically, the decision to rely on automation under stressful conditions. Stress consumes executive resources (Hermans ... -
Group 3 unmanned aircraft systems maintenance challenges within the Naval Aviation Enterprise
Park, John D. (Monterey, California: Naval Postgraduate School, 2017-12);The Naval Aviation Maintenance Program (NAMP) creates maintenance and manpower inefficiencies for current Group 3 unmanned aircraft systems (UAS) (55 to 1,320 lbs). The primary output of this study was the creation of ...