I have been working either with industry in collaborative research or directly for industry as an R&D specialist for nearly forty years. I have worked on all phases and types of semiconductor devices. The devices range from MOS-based technologies to solar cells. The photovoltaic technology has been my primary interest for the last twenty years. An area of specialization in all of the above fields has been material and device characterization. The range of materials varies from high quality float zone silicon, epitaxial GaAs to polycrystalline thin films, and carbon nanotubes.

An area of particular specialization has been the analysis and measurement of the minority-carrier lifetime in all of these materials. I have developed the time-resolved photoluminescence technique for application to lifetime measurements and used if for direct bandgap semiconductors such as GaAs and CdTe. I invented a novel technique in the late 1990s called resonance coupled photoconductive decay (RCPCD) which has been applied to all of the above materials. I currently have access to these measurements at several different research institutions.

In addition to the above, I have worked with most the the popular measurement techniques for measuring minority- and majority carrier properties of materials. The latter include energy-resolved photoluminescence, capacitance-voltage measurements, deep level transient spectroscopy, Hall effect, and resistivity techniques.

Finally, I have worked specialized in the physics of devices, and taught the graduate course in semiconductor devices and photovoltaic devices for over ten years at the University of Colorado and the Colorado School of Mines. I have also taught a short course for the American Vacuum Society for over twenty years. The course title is the The Electrooptical Characterization of Semiconductors.



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