LASER ABLATION INDUCED RECOMBINATION LOSSES OF N-PERT-RJ SOLAR CELLS WITH REAR CONTACTS FORMED BY AL EVAPORATION

摘要

In this work, we use photoluminescence (PL) imaging to extract V_(oc) and J_(01) as a function of laser ablation of the rear side dielectric layer of n-PERT-RJ solar cell precursors. The linear fit of the experimental data yields different values for the emitter recombination current density according to the ablation patterns and varied laser settings. We quantified the damage on the laser treated surface by extraction of the laser ablation induced emitter recombination current density (J_(0e-ablation)) and found a decrease from 2200 fA/cm~2 to 780 fA/cm~2 in our experimental matrix. We also monitored the impact on J_(0e) induced by cleaning and metallization after the laser process. With the quantification of the emitter surface recombination and Optical surface inspection, we improved our n-PERT-RJ solar cells with Alevaporated rear contact to an efficiency of 20.8%.