The Laboratory for Photovoltaics (LPV) works on new materials for solar cells.
We focus on two issues:
- The development of new structures and processes for the preparation of thin film solar cells and
- The fundamental materials physics of novel semiconductors used as absorbers in these devices.
We concentrate on chalcopyrites (Cu(InGa)Se 2 CIGS) and related materials. These semiconductors are interesting from the application point of view as well as from a fundamental physics perspective.
Thin film solar cells are considered the next generation of photovoltaics because of their enormous cost reduction potential which is based on the greatly reduced consumption of material and energy. Among the currently available technologies solar cells based on chalcopyrite absorbers show the highest efficiencies on the laboratory scale as well as in industrial production.
Besides this technological interest, chalcopyrites show also unusual physical properties, concerning their phase behaviour, their electrical doping properties, their surface physics and their grain boundaries, which can be traced to the exceptionally low formation energies of native defects. We study the defects in these materials by applying optical and electrical spectroscopic methods to single crystalline films prepared by epitaxy and polycrystalline films as used in the solar cells.
The laboratory was founded in 2007 in the framework of the TDK Europe professorship and is headed by Prof. Susanne Siebentritt.
Four current and former members of LPV received the “FNR Award for Outstanding Publication” in 2014:
In November 2015, Prof. Siebentritt received the “Grand Prix en sciences physiques – Prix Paul Wurth” of the Institut Grand Ducal: