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Electrical and Computer Engineering

Dissertations, Theses, and Masters Projects

2000

Articles 1 - 3 of 3

Full-Text Articles in Engineering

Factors Affecting Carrier Transport In Ultrafast Iii-V Compound Semiconductor Based Photodiodes, James Alexander Mcadoo Jan 2000

Factors Affecting Carrier Transport In Ultrafast Iii-V Compound Semiconductor Based Photodiodes, James Alexander Mcadoo

Dissertations, Theses, and Masters Projects

This dissertation describes a comparative study conducted on GaAs MSM photodetectors to assess the importance of surface effects on the optical and frequency response characteristics of MSM photodetectors. MSM photodetectors on III-V compound semiconductors are technologically important because of their applications to fiber optic communication systems. While surface effects have been previously ignored, they must be considered in assessing the ultimate performance limits of such devices, especially if nanoscale MSM photodetectors are to be used. A controlled study was carried out in which high quality devices were subjected to surface damage over a known range and the resultant effects of …


Low Damage Processing And Process Characterization, Xianmin Tang Jan 2000

Low Damage Processing And Process Characterization, Xianmin Tang

Dissertations, Theses, and Masters Projects

Two novel plasma sources (one neutral source and one pulsed inductively coupled plasma source) and ashing process characterization were investigated. The primary goal was to characterize these source properties and develop corresponding applications. The study includes process damage assessment with these two sources and another continuous wave (13.56MHz) plasma source. A global average simulation of the pulsed discharges was also included.;The transient plasma density and electron temperature from the double probe analysis were compared with single Langmuir probe results with sheath displacement corrections in pulsed discharges (200Hz--10kHz). The equivalent resistance method can be used effectively to analyze these double probe …


Lamb Wave Diffraction Tomography, Eugene V. Malyarenko Jan 2000

Lamb Wave Diffraction Tomography, Eugene V. Malyarenko

Dissertations, Theses, and Masters Projects

As the worldwide aviation fleet continues to age, methods for accurately predicting the presence of structural flaws, such as hidden corrosion and disbonds, that compromise air worthiness become increasingly necessary. Ultrasonic guided waves, Lamb waves, allow large sections of aircraft structures to be rapidly inspected. However, extracting quantitative information from Lamb wave data has always involved highly trained personnel with a detailed knowledge of mechanical waveguide physics. In addition, human inspection process tends to be highly subjective, slow and prone to errors. The only practical alternative to traditional inspection routine is a software expert system capable of interpreting data with …