Appl Phys Lett 2008, 92:132901–3.CrossRef 30. Liu R: Imaging of photoinduced interfacial charge separation in conjugated polymer/semiconductor nanocomposites. J Phys Chem C 2009, 113:9368–9374.CrossRef 31. Diesinger H, Mélin T, Deresmes D, Stiévenard D, Baron T: Hysteretic behavior of the charge injection in single silicon nanoparticles. Appl Phys Lett 2004, 85:3546–3548.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions SW carried out the experiments. ZLW prepared the samples.

SW and XJY interpreted the results and wrote the manuscript. DDL participated in manuscript preparation. ZYZ and ZMJ helped in interpretation and discussions. All authors read and approved the final manuscript.”
“Background Over the past few years, many researchers have shown an interest in silicon see more nanostructures, such as silicon nanocrystals [1–4] and silicon nanowires [5–8] for solar cell applications. Since a silicon nanocrystal embedded in a barrier

material can make carriers confined three-dimensionally, the Belnacasan molecular weight absorption edge can be tuned in a wide range of photon energies due to the quantum size effect. Thus, it is possible to apply silicon nanocrystal materials or silicon quantum dot (Si-QD) materials AZD6738 clinical trial to all silicon tandem solar cells [9], which have the possibility to overcome the Shockley-Queisser limit [10]. Moreover, it has http://www.selleck.co.jp/products/Verteporfin(Visudyne).html been found that the weak absorption in bulk Si is significantly enhanced in Si nanocrystals, especially in the small dot size, due to the quantum confinement-induced mixing of Γ-character into the X-like conduction band states [11]. Therefore, Si-QD materials are one of the promising materials for the third-generation solar cells. Size-controlled Si-QDs have been prepared in an amorphous silicon oxide (a-SiO2) [12], nitride (a-Si3N4) [13], carbide (a-SiC) [14–17], or hybrid matrix [18, 19], which is called as silicon quantum dot superlattice structure (Si-QDSL). In the case of solar cells, generated carriers have to be transported

to each doping layer. Since the barrier height of an a-SiC matrix is relatively lower than that of an a-Si3N4 or a-SiO2 matrix, the Si-QDSL using an a-SiC matrix has an advantage in carrier transport. Therefore, the development of the Si-QDSL solar cells using an a-SiC matrix is of considerable importance. There are a few researches fabricating Si-QDSL solar cells. Perez-Wurfl et al. reported that Si-QDSL solar cells with SiO2 matrix showed an open-circuit voltage (V oc) of 492 mV. However, the clear evidence of the quantum size effect has not been reported from Si-QDSL solar cells [20]. In our previous work, Si-QDSLs with a-SiC matrix have been prepared by plasma-enhanced chemical vapor deposition (PECVD).