%0 Journal Article
%T Enhanced Visible Light Absorption by 3C-SiC Nanoparticles Embedded in Si Solar Cells by Plasma-Enhanced Chemical Vapor Deposition
%A Bhaskar Parida
%A Jaeho Choi
%A Gyoungho Lim
%A Kiseok Kim
%A Keunjoo Kim
%J Journal of Nanomaterials
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/953790
%X Solar cells with 3C-SiC nanoparticles embedded in the Si were investigated by plasma-enhanced chemical vapor deposition. Several sizes of SiC nanoparticles were used as the intermediate layer for the solar cell. The Si thin films showed the formation of micro- and nanocrystallites on the SiC nanoparticle sites, which play an important role of heating block as a nanosubstrate. The Raman spectra revealed that the SiC nanoparticles were embedded in mixed phases of amorphous and nanocrystalline Si. Compared to the conventional solar cell sample, the photoreflectance was significantly reduced in the UV/visible spectral region due to the presence of the embedded 3C-SiC nanoparticles. The Si nanocrystals formed by the thin film deposition played an important role in reducing the photoreflectance within the visible to infrared spectral zones. Furthermore, the SiC nanoparticles contributed less in the photoabsorption at a longer infrared spectral zone wavelength of 1200£¿nm. 1. Introduction In recent years, several nanostructures, such as nanowires, quantum dots, photonic crystals, and ultra-small nanoparticles, have been widely investigated to improve the efficiency of Si solar cells [1¨C4]. These ultra-small nanoparticles used in Si solar cells enhance the light coupling in the ultraviolet (UV)/visible spectral range to increase the radiative recombination of photoexcited excitons and carrier transportation and produce a high voltage with improved power performance [5]. Si solar cells have very low UV spectral response due to low band gap energy ( ), which is a major limitation for collecting photogenerated carriers across Si to generate electrical energy from the UV spectra. To overcome such limitation, nanocrystals have been hybridized on Si solar cells to achieve a twofold enhancement in the cell efficiency under UV light, and wide band gap materials have been used [6]. Silicon carbide (SiC) is an indirect and wide band gap ( ) semiconductor with quite good electrical properties such as high electron mobility and saturation drift velocity. SiC is widely used in photonics and optoelectronics [7, 8]. SiC/TiO2 nanocomposites can be used as a photoelectrode that produces high power conversion efficiency in dye-sensitized solar cells [9]. SiC used as a window layer in a homojunction photodiode enhances the quantum efficiency with increased photo response in the shorter wavelength spectral region [10]. Furthermore, colloidal SiC nanocrystals absorb light in the UV/visible spectral range [11] and act as an antireflection coating on the Si solar cell [12]. Therefore,
%U http://www.hindawi.com/journals/jnm/2013/953790/