Influence of Nickel Impurity on the Operating Parameters of a Silicon Solar Cell

Abstract

The research results present the influence of nickel impurities introduced by diffusion into monocrystalline silicon on the characteristics of solar cells (SCs). It is established that doping with nickel atoms makes it possible to increase the lifetime of the MCCs in the material by up to a factor of two and the efficiency of SCs by 20–25%. It is shown that the distribution of nickel clusters in the volume of the material is almost uniform, and their size does not exceed 0.5 μm. The concentration of clusters in the volume is ~10¹¹–10¹³ cm^–3; and in the near-surface layer, ~10¹³–10¹⁵ cm^–3. The physical mechanisms of the influence of the bulk and near-surface clusters of nickel atoms on the efficiency of silicon SCs are revealed. It is experimentally established that the decisive role in increasing their efficiency is played by the processes of gettering of recombination-active technological impurities by nickel clusters, occurring in the nickel-enriched front surface region of the SCs.