Improved open-circuit voltage of silicon nanowires solar cells by surface passivation

Abstract

The surface recombination at the surface of silicon nanowires (SiNWs) deteriorates the performance of SiNWs solar cells and thus the reduction of the SiNWs surface recombination becomes a crucial issue. In this paper, we observe an improved SiNW surface passivation by hydrogenated amorphous silicon (a-Si:H). The results show that a thicker i-layer results in a higher open-circuit voltage V oc . That can be ascribed to the better passivation by thicker intrinsic a-Si:H. The dark current-voltage data reveal that the reverse leakage current and the diode ideality factor at high forward bias decrease monotonically with increasing the thickness of i-layer. Moreover, for the first time, we observe that the lower V oc is associated with the capacitance-voltage (C-V) curve shifting toward higher positive voltage. We propose that the shift of the curve is related to the capacitance affected by the surface states. Finally we prove that the improvement in the NW solar cell performance, especially the V oc , can be attributed to the reduction of the surface states on SiNWs.

Effect of Assets of Silicon Film Passivation Layer on the Performance of Silicon Nanowire Solar Cells

“…Much surface states on SiNWS causing photo carrier recombination is one of possible reasons . We have proved that the improvement in V oc of NW-based solar cell can be attributed to the reduction of surface states on SiNWs [9]. Moreover, a fundamental question yet to be answered regards the link between the properties of the intrinsic silicon film and solar cell performances.…”

Functionalization of Silicon Nanostructures for Energy‐Related Applications

“…There have been a number of reports on the effects of surface passivation. Passivation layers such as SiO 2 , Al 2 O 3 , and SiN x and hydrogenated amorphous Si have been well investigated . The surface passivation of nc‐Si QDs is also a key process for the above‐mentioned NRET.…”