Efficiency Comparison of MWT and EWT all Backcontact Nanowire Silicon Solar Cells

Nanowire Solar cells (NW SCs) have shown hopeful advance for light absorption and charge carrier transport because in a vertical structure absorption and carrier transport are orthogonal to each other. In this work high-efficiency back-contact back-junction (BC-BJ) structures like emitter wrap through and metallization wrap through Silicon (Si) SCs for one-sun applications were studied. The top portion of the device gets fully illuminated and there is no loss incorporated due to the absence of front metallization. Key parameters were extracted of proposed structure and a vertical NW SC structure with a front contact using 3D-TCAD simulation tool. First of all a comparison in the performance is observed between a planar solar cell (PSC) and a NW SC, then two different types of all back contact (ABC) structures are studied. The entire work is simulated using AM1.5G solar spectrum at room temperature. The key solar parameters like open circuit voltage (V_OC), short circuit current (I_SC), fill factor (FF), short circuit current density (J_SC) and conversion efficiency are calculated. The efficiency of the proposed structure is more comparable to a regular NW structure which is considered with similar device characteristics.