Programm Photovoltaik Ausgabe 2009 ... - Bundesamt für Energie BFE

Introduction / Project Goals
Prior to this project, on small area (4.5x4.5mm 2 ) cells without metallization, an open-circuit voltage
higher than 700 millivolt and an efficiency of 19% were achieved on flat monocrystalline wafers at the
University of Neuchâtel [1]. Here, we continue to work on such heterojunctions. The specific scientific
and technological project objectives are to demonstrate:
� the fabrication of ultra-high-efficiency silicon heterojunction solar cells (>20% on “standard” configurations
or even higher with novel device structures), based on a combination of amorphous/microcrystalline
layers and thin crystalline wafers (down to 100µm).
� that the process is up-scalable to large area solar cells (>100cm 2 ) which should achieve efficiency
over 20%.
� a new metallization/encapsulation process capable to lead to a fabrication of high-efficiency and
lightweight (