Economical Patterning of Series Connected a-Silicon Modules

Different patterning methods are used for manufacturing series connected stripe like cells in a-Si modules whith thin film technologie. These line patterns cause a loss of active cell area, defined by the edge quality of the lines. Screen printing is favorized as a highly economic process. Two new screen printing methods for patterning SnO2 and metal are presented. The patterning sequence: TCO with screen printing/lift off technique, a-Si with mechanical milling or slotting and metal with screen printing/lift off technique is qualified as the most inexpensive patterning process for solar modules leading to patterning costs of about 1.-DM for modules of a 30 × 30 cm2 area.