UMD Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/3

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a given thesis/dissertation in DRUM.

More information is available at Theses and Dissertations at University of Maryland Libraries.

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Author: search.filters.author.Huebschman, Benjamin DavidSubject: search.filters.subject.Gallium Nitride

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    INVESTIGATION OF RELIABILITY IN GALLIUM NITRIDE HIGH ELECTRON MOBILITY TRANSISTORS USING EQUIVALENT CIRCUIT MODELS FOR USE IN HIGH POWER, HIGH FREQUENCY MICROWAVE AMPLIFIERS
    (2010) Huebschman, Benjamin David; Goldsman, Neil; Electrical Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Gallium Nitride (GaN) is beginning to emerge as an alternative to the Gallium Arsenide in high power, high frequency microwave communications. Other novel semiconductors show potential at higher frequency applications. The largest obstacles to GaN emerging as the dominant microwave semiconductor are the issue of cost, which could be reduced through volume, and question of reliability. A new approach to the analysis of reliability has been developed based on the periodic generation of equivalent circuit models while a device is stressed in a manner that is similar to performance likely to be seen during commercial operation. Care was made in this research to ensure that the stress measurements used to induce degradation are as close as possible to those that would degrade a device in real world applications. Equivalent circuit models (ECM) can be used to simulate a device in computer aided design (CAD) software, but these models also provide a picture of the physical properties within the device at a specific point in time. The periodic generation of ECMs allows the researcher to understand the physical changes in the device over time by performing non-destructive electronic measurements. By analyzing the changes in device performance, the physical mechanism of device degradation can be determined. A system was developed to induce degradation and perform measurements of sufficient detail to produce a large signal ECM. Software for producing the ECM was also created. The changes in the ECM were analyzed to diagnose the physical changes in the device under test (DUT) and to identify a method of degradation. The information acquired from this system can be used to improve the device manufacturing process at the foundry. It can also be used to incorporate device degradation into the operation of systems.