Comparison of innovative metallization approaches for silicon heterojunction solar cells

Within this study, different metallization approaches were investigated and compared with respect to their applicability for silicon heterojunction (SHJ) solar cells. A printed line width of 34 μm with an aspect ratio of 0.59 was reached by double fine-line screen printing. In parallel, ink jet printing and its applicability regarding in-situ curing was evaluated. It was found that spreading of the ink is substantially reduced by choosing the optimum substrate temperature, enabling for a line width of 32 μm. Successful dispensing of a low-temperature silver paste was achieved by using a ten nozzle print head. By means of screen printed contact grids on both sides, solar cells with a conversion efficiency of 21.9 % were produced with industrial precursor wafers