Amorphous silicon solar cells with stable protocrystalline silicon and unstable microcrystalline silicon at the onset of a microcrystalline regime as i-layers

We investigated the light-soaking and thermal annealing behaviors of amorphous silicon-based solar cells incorporating hydrogen-diluted amorphous silicon films as i-layers deposited at several hydrogen dilution ratios. From the investigation, we confirmed that protocrystalline silicon was most stable against light soaking, and also that the film deposited at the onset of the microcrystalline regime, which was known to have the most competent device quality and stability, was less stable. Charged dangling bonds defects caused by the inhomogeneous microstructure of the onset of the microcrystalline regime during light soaking were suggested as one of the reasons for the instability at the onset regime.