Optimization of n-type silicon solar cell front side contacts

In order to maximize the power output of a solar cell, the front surface metallization must efficiently transmit the generated power while minimizing the shadowing losses arising from the grid pattern area. In this work, the sheet resistivity of the emitter and finger spacing aspects are neglected. Instead, the optimization of finger and busbar geometry is considered analytically to minimize the total power losses. It is found that linearly tapered (triangular) contacts are the most efficient geometry and that the position of the busbar highly influences the maximum cell output. To study the influence of the optimized contacts on the performance of a solar cell, a shadow mask was designed, and boron emitter n-type silicon solar cells were fabricated with the optimized contacts.