Efficiency potential of n-type silicon solar cells with aluminum-doped rear p+ emitter

We present a detailed analysis on the efficiency potential of n -type silicon solar cells with aluminum-doped rear p + emitter for industrial applications by means of 2-D and 3-D numerical simulations. Thereby, this study examines successively three different regions of the solar cell. First, the front side is investigated by discussing the influence of different uniform and selective front surface fields (FSFs). Additionally, the case of omitting a full-area FSF and only applying local heavily doped areas below the front contacts is analyzed. Second, we look into the base and how doping concentrations and finger distance variations influence each other. Finally, the back side of this solar cell concept is examined by 3-D simulations, demonstrating the effect of a surface-passivated and locally contacted aluminum-doped rear p + emitter on the cell performance. As a result of our considerations, we have determined an efficiency potential for this $n{+}np + cell concept close to 21%.