Published online by Cambridge University Press: 01 February 2011
We report on the measurement of local current flow in hydrogenated amorphous and nanocrystalline mixed-phase n-i-p silicon solar cells in the initial, light-soaked, and annealed states using conductive atomic force microscopy (C-AFM). The C-AFM measurement shows that the nanometer-size grains aggregate, and the local current densities in the nanocrystalline aggregation areas decreased significantly after light soaking and recovered to values similar to the initial state after annealing at a high temperature in a vacuum. This result supports the model of two parallel-connected diodes for explaining the light-induced open-circuit voltage increase in the mixed-phase solar cells.