Optical, electrical, and photovoltaic properties of silicon nanoparticles with different crystallinities

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. (C) 2015 AIP Publishing LLC.