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31. Zhu J, Yu Z, Burkhard FG, Hsu MC, Connor TS, Xu Y, Wang Q, McGehee M, Fan S, Cui Y: Optical absorption enhancement in amorphous silicon nanowire and nanocone arrays. Nano Lett 2009, 9:279–282.CrossRef 32. Smith EZ, Chu V, Shepard K, Aljishi S, Slobodin D, Kolodzey J, Wagner S, Chu LT: Photothermal and photoconductive determination of surface VX-680 mw and bulk defect densities click here in amorphous silicon films. Appl Phys Lett 1987, 50:1521–1523.CrossRef Competing interests The NSC23766 mouse Authors declare that they have no competing interests. Authors’ contributions ESA conceived of the study and participated in its design and coordination as well carried out the fabrication and characterization of the a-Si:H/SiNW solar cell. Moreover, ESA interpreted

the results and prepared the manuscript. MYS was involved in drafting and revising the manuscript. MHR, KS, ESA, and MYS have given final approval of the manuscript to be published.”
“Background Materials consisting of silicon nanocrystals (Si-NCs) embedded in a dielectric matrix are one promising candidate to realize Si-based

third-generation photovoltaic devices owing to their potential benefits of utilizing the visible light of terrestrial solar spectrum and overcoming the efficiency limit of crystalline Si (c-Si) solar cells [1–5]. Sub-stoichiometric Si-based dielectric materials, such as SiO x , SiN the x , and SiC x , have been investigated for synthesis of Si-NCs [6–11]. The formation of Si-NCs is based on phase segregation and crystallization in Si-rich dielectric films during the post-annealing process [12]. The low conductivity of Si-NCs embedded in dielectric films limits their applications for the manufacturing of optoelectronic devices. For this reason, impurity doping in Si-NCs embedded in SiO2 has been demonstrated to modify the electrical properties of the layers, although there is some debate about the feasibility of doping in Si-NCs [13, 14]. In addition to impurity doping, the choice of the surrounding dielectric matrix also plays a crucial role in charge carrier transport. Although the formation of Si-NCs in the SiO2 matrix has been investigated in detail [12, 15], the carrier transport ability in the Si-NC network is generally insufficient due to the large energy barrier of the surrounding oxide matrix. Charge carrier transport through narrower bandgap dielectrics, such as Si3N4 or SiC, seems to be more feasible.