Current researches on silicon nanoparticles (Si NPs) are mainly focusing on the crystallized one, while some basic optical and electrical properties of particles with different crystallinities are still unclear. Hence, in this work, Si NPs with different crystallinities were easily fabricated with non-thermal plasma by changing the input power, and the crystallinity effects on the optical, electrical, and photovoltaic properties of particles were extensively studied. It is found that amorphous particles have strong light absorption, especially in short wavelength region; however, the carrier mobility is relatively poor. This is mainly because of numerous dangling bonds and defects that exist in Si NPs with poor crystallinity, which work as carrier trapping centers. As a result, the efficiency of Si NPs-based hybrid solar cells increases monotonously with particle crystallinity. This indicates that highly crystallized Si nanocrystals with less defects are desirable for high efficiency solar cells.

Electric resistance of metals increases according to the elevation in temperature. Non-uniform temperature distribution in cross-section can be automatically sacrificed if we use electric resistance heating, and uniformly distributed cross-sectional temperature can be easily obtained. A continuous heating system using electronic resistance heating is developed, and its characteristics to the heating of stainless steel are examined through a series of basic experiments. Through the investigation, it has become clear that uniform continuous heating of stainless steel can be realized by proposed heating system. Although the composition of heating system is quite simple, high rate in temperature elevation can be obtained. Also, we can precisely control the temperature distribution in feeding (rolling) direction by continuous electric resistance heating, because temperature of metals can be rapidly changed only by changing the degree of electric current and time to impose electric current.

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