Effect of hydrogenated silicon film microstructure on the surface states of n-type silicon nanowires and solar cells

Here various microstructure hydrogenated silicon has been used to passivate n-type silicon nanowires (SiNWs) and its core/shell solar cells. There are two differences in photoluminescence (PL) spectroscopy between SiNWs and passivated SiNWs: (a) the increased PL intensity and (b) a blue-shift of the PL peak. Through analyzing the PL results, we found the infrared band at 800 nm is associated with dangling bonds on SiNWs. The performance of the core/shell SiNWs solar cells are improved attributed to reduced surface defects by the intrinsic Si:H layer passivation. Furthermore, the passivation effect with a-Si:H layer is better than its counterpart with µc-Si:H layer, which is due to the different microstructures especially the hydrogen-terminated.