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Selective homoepitaxial growth of 4H-SiC polytype at temperatures down to 1300°C was investigated using novel halo-carbon epitaxial growth technique. More than three times higher growth rate than in blanket epitaxy without morphology degradation was due to the local loading effect, which demonstrated that the growth rate of SiC homoepitaxy at low temperatures is limited by the gas-phase reaction mechanisms rather than surface mechanisms. It was established that the step-flow growth without undesirable nucleation may be maintained at growth rates in excess of 6μm∕h. Strong dependence of the growth rate on the ratio of the seed area to the masked area indicated that the growth rate is predominantly mass transport limited. Facet formation and conditions for suppressing defect generation at the mesa walls were investigated.

There is an increasing use of handheld spectroradiometer data for "ground truthing" of hyperspectral imagery, as well as conducting pilot studies where hyperspectral imagery may eventually be used. There exists a need for standalone software that can be used for organizing, displaying, preprocessing, and analyzing large collections of handheld hyperspectral signatures. The authors of this paper have created a shareware package, HyperSpec, for such tasks. This paper provides details of HyperSpec as well as an example application of the software to an invasive species detection project.

This paper presents active current-equalization (CE) techniques for equalizing the lamp currents of multi-lamp electronic ballasts. Multi-lamp products, such as the backlighting for liquid crystal display (LCD) panels, have to be capable of equalizing luminance. Due to the deviations of lamps and ballasts, the currents flowing through the lamps are not equal, which causes poor-quality backlight sources for LCD panels. Additionally, since the size of thin-film transistor LCD (TFT-LCD) monitors is becoming larger, a multi-lamp drive system must provide higher levels of voltage and current and more power for longer length lamps and more lamps. Since the number of lamps that can be driven by one inverter is limited, distributed multi-ballast drive systems are becoming popular.In order to achieve current equalization for distributed multi-ballast drive systems, the active CE technique is proposed to equalize every output current of the ballast.In this paper, the three-ballast drive system, for distributed single-lamp inverters, is implemented with the active CE technique. In addition, the CE ability in dimming range is demonstrated by experiments in order to verify the performance of the proposed active CE circuit scheme.Index Terms-Liquid crystal display (LCD) panels, thin-film transistor (TFT).

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