Optimization of capillary suspension silver pastes for enhanced metallization in silicon solar Cells: A comparative analysis of Screen-Printing and pattern transfer printing

With the increase in the use of crystalline silicon solar cells, it is necessary for solar cells to achieve finer and higher pre-metallization finger lines. The application of capillary suspension can alter the paste from a weakly elastic state to a highly elastic or even gel-like behavior. The preparation of a frontal silver paste based on a capillary suspension is beneficial in adjusting the rheological properties of the silver paste over a wider range. Two distinct printing methods were employed: screen-printing and laser-pattern transfer printing (PTP). Combined with the results of material, rheology and printing, the optimization of capillary suspended silver paste was explored. This article mainly introduces the elements of silver paste formation in capillary suspension and the effects of PTP technology. The metalized finger line achieved an aspect ratio of 0.63 and a transfer yield of 96 % through PTP. Compared to commercial silver paste for comparison, the transfer power is reduced by 80-100 W while achieving good transfer. It reduces the line resistance of the cell and increases the short-circuit current density (Jsc). Following the simulation of the electrical performance of the cells' post-transfer, there was observed to be an improvement in Jsc, Voc, and Eta in comparison to the performance of commercial silver paste.