The effect of hydrogenation on the electrical property of a clean grain boundary in the p-type direct silicon bonded wafers was investigated by current-voltage (I-V) and capacitance-voltage(C-V) deconvolution. It was found that compared to the as-bonded grain boundary, the energy distribution of interface states at the grain boundary subjected to hydrogenation became shallower, and the hole capture cross-section could be reduced by about two orders of magnitude, while the density of grain boundary states changed only slightly. Therefore, a significantly smaller potential barrier of grain boundary could be obtained after hydrogenation. These results were interesting for understanding the mechanism of hydrogen passivation of grain boundaries in photovoltaics.

Hydrogenation of Interface States at a Clean Grain Boundary in the Direct Silicon Bonded Wafer. T.Jiang, X.Yu, X.Gu, D.Yang, G.Rozgonyi: Physica Status Solidi A, 2012, 209[5], 990-3