MBE Laboratórium

MBE laboratory


The MBE system of the Wigner Research Centre has been operational since October 2003. The 13 atom sources are loaded in 2 e-guns and 5 effusion cells for co-evaporation and even complex multilayer sequences without the need of venting the chamber. The UHV system consists of a load-lock, a heat treatment chamber as well as the main deposition chamber. The system handles substrates of up to 2-inch. Prior to the sample preparation, the substrate is cleaned and mounted on a Mo block, then introduced in the UHV through the load-lock, optionally pre-heated then transported to the main chamber for film growth, where it may be rotated for better lateral homogeneity. The layer thickness is monitored by quartz thickness monitors, the surface structure can be samples by RHEED. Residual gas analysis is performed by quadrupole mass spectrometry. The laboratory is capable of growing a very wide selection of (multi)layer systems from below monoatomic layers to layers of about 100 nm thickness of almost any metallic and some compound targets (e.g. MgO). Moreover, a controlled gas source is available for gently flushing the chamber with gases of 10-6 to 10-11 mbar pressures controlled wihin a few per cent. For their significance in applied nuclear physics, two of the simultaneously available 13 atom sources, 57Fe and 62Ni sources have been installed in the growth chamber for isotope-selective multilayer growth, to prepare samples for 57Fe Mössbauer spectroscopy and nuclear resonance scattering or contrast enhancement or contrast matching samples for neutron scattering.