Anna Fontcuberta i Morral: Ultra-Pure nanowire heterostructures
© 2009 EPFL
The excellence of the research performed at EPFL has once again been recognized at an international level. Anna Fontcuberta I Morral has received a STARTING GRANT 2009 from the European Research Council (ERC).
Ultra-Pure nanowire heterostructures and energy conversion
This proposal is devoted to the synthesis of ultra-pure semiconductor nanowire heterostructures for energy conversion applications in the photovoltaic domain. Nanowires are filamentary crystals with a very high ratio of length to diameter, the latter being in the nanometer range. Nanowires are of significant interest owing to their large surface-to-volume ratio and low-dimensional properties, as well as attractive building blocks of novel devices, including for novel energy conversion applications. The most widely employed nanowire growth method relies on the use of gold, which is known to be an impurity limiting mobility and carrier lifetime in semiconductors. It is generally realized that nanowires with higher purity could enable significant advances in both fundamental studies and technological applications. This proposal combines two complementary and essential aspects of semiconductor nanowires: (i) synthesis in extremely clean conditions and (ii) their application to new concepts of photovoltaic devices. The first part involves the use of Molecular Beam Epitaxy (MBE) system for the synthesis of III-V semiconductor nanowires and heterostructures. Special emphasis will be given in the synthesis of new heterostructure designs, i.e. across the nanowire radius and along the growth axis. The fabrication of ordered arrays of nanowires on large areas and on silicon substrates will also be investigated. In the second part, nanowire based solar cells will be designed, fabricated and characterized. Particular emphasis will be given toward understanding the role of geometry and interfaces in the energy conversion efficiency of the novel nanowire-based solar cells. Here, the high cleanliness and precise heteroepitaxial growth of MBE nanowires will allow us to perform fundamental studies, generating ground-breaking knowledge on the microscopic processes in energy conversion. This project will foster the use of nanotechnology in the energy challenges of the XXI century.
Max ERC funding: 1.29 million Euros
Duration: 60 months
Host institution: EPFL
Project acronym: UPCON
Domain: Physical and Engineering Sciences