Joining bottom-up and top-down in materials research: Molecular beam epitaxy and focused ion beams in the same ultra-high vacuum
Andreas D. Wieck, Ruhr-Universität Bochum, Bochum, GermanyArne Ludwig, Angewandte Festkörperphysik, RUB, Bochum, Germany
We grow by molecular beam epitaxy (MBE) bandgap-engineered GaAs-based semiconductor layers, InAs quantum dots and quantum wires. These systems are doped or modified by focused ion beam (FIB) implantation using an ultra-high vacuum (UHV) transfer path. In this way, the MBE-growth and FIB implantation are performed in any sequence and maskless lateral patterning without surface chemistry or exposition to air/moisture is possible. We are able to produce any metal of the periodic table in the FIB beam (from Li to Bi), including rare earths. This leads to an enormous flexibility and superior quality of the devices produced monolithically in the UHV and being independent of surface states or other contaminations.