Silver Pastes Capable of Narrow Line, High Aspect Ratio and High Pastes Transferability for Knotless High Mesh Screen Printing

It is a challenge to transfer enough silver conductive paste to maintain low series resistance when print narrow and high aspect ratio finger lines, using high mesh and narrow opening screens. This work presents development of a new silver paste with a high paste transferability for crystalline solar cell front side metallization. The pastes are able to be printed through 400 mesh and 23μm opening knotless screens, resulting in finger line width of 40 microns and an aspect ratio of 0.54. A high paste transfer capability is believed to be the key factor for the narrow and high aspect ratio finger lines. Electrical performance, such as efficiency, Isc and Rs etc. will also be compared with a commercially available product.