Electrochemical behavior of Ni seed layers on polysilicon wafer for solar cells

The stripping behaviors of Ni seeds on polysilicon wafers, which were formed by galvanic displacement in a solution containing fluorine ions, were characterized by cyclic voltammetry and the surface morphologies were observed by scanning electron microscopy. It is discovered that the anodic stripping behaviors of the Ni seed layers are impacted by the duration of deposition. Two types of Ni seed layers can be distinguished. One is formed with the deposition duration less than 10 s, which corresponds to the stripping behavior of the Ni-Si structure with monolayer deposition. The other is formed with a duration greater than 10 s, which is attributed to the stripping behavior of the Ni-Ni-Si structure with bulk deposition.