Emitter Requirements for Nickel Contacts on Silicon Solar Cells-A Simulation Study

A unified model for the nickel-silicon theoretical contact resistivity was computed, using a 0.6 eV Schottky barrier height, and compared to recent experimental data. This model was subsequently inserted in a classical co- optimization procedure. Numerical simulations were combined with analytical power losses equations to find out the effect of homogeneous emitter doping profile on an ideal lab-scale silicon solar cell. According to this work, an optimized emitter for plated contacts on a 10 μm wide nickel seed layer should have a junction depth ranging from 0.5 to 4 μm and a surface doping from 4 x 1018 to 2 x 1019 cm-3. This broad range allows getting more than 25.5% and up to 25.9% theoretical efficiency on a 2 x 2 cm2 silicon solar cell metallized with 10 μm thick fingers. Finally, contour plots were also simulated using a larger Schottky barrier height in order to figure out the effect of the nickel silicide contact interface on solar cell properties.