Options
2009
Conference Paper
Titel
Development of via pastes for high efficiency MWT cells with a low shunting behaviour
Abstract
A key component for MWT solar cells is the interconnection between front and rear side. Therefore, a reliable connection with low series resistance losses between front and rear side is necessary. This can be achieved by a high quality via paste. Furthermore, a low shunting behaviour is a must for the via paste in order to maintain high fill factors for MWT solar cells [3,4]. Moreover, the printability of the via paste needs be optimized to perform a proper via metallization. To implement this key factors, an extensive development was set up consisting multiple phases of experiments. In this work the coarse survey of the design process is described, which successfully results in an optimized silver via paste formulation to achieve best electrical and mechanical performance. These pastes were tested within an industrial applicable MWT process flow developed at the pilot-line of the PV-Technology Evaluation Center (PV-TEC) at Fraunhofer ISE Freiburg [5] as well as within the pilot-line of the cell manufacturer Bosch Solar Energy AG [8,9]. Feasibility and reliability of paste and process are demonstrated with the potential to generate an efficiency gain up to 0.5% absolute compared with conventionally processed solar cells.
Author(s)