Nanocluster

The institute hosts a state-of-the-art multi-material cluster (NanoCluster) tool. The tool provides a unique combination of nine UHV epitaxial/deposition systems including MBE, ALD, and sputtering. It offers the possibility for in-situ growth of complex nanostructures from III-V and II-VI (ZnSe based) semiconductors, metals, oxides, nitrides, magnetic and phase change materials. The in-situ growth can reduce significantly the interface density of states resulting in improved (opto-) electronic nanodevices and offering the chance to study new quantum phenomena. The cluster tool is potentially an ‘alembic’ for developing new materials and hybrid structures in ultra clean conditions. The NanoCluster provides a platform for the work of various institutes at Forschungszentrum Jülich (PGI-10, PGI-9, PGI-7, PGI-6) and RWTH Aachen University (I. Institute of Physics IA).
Due to UHV transfer enabled between the deposition systems, like for example off-axis metal and oxide sputtering and atomic layer deposition, this tool is utilized for RRAM research focusing on interfacial effects of in-situ stacked sub 10 nm thin metal oxide and metal layers for concepts on three dimensional integrated RRAM.

Moreover, the growth of nanowire hetero- and hybrid- structures for the processing of TFETs is employed. Processing and characterization of devices from the grown structures complete the activity. In a first stage, we have successfully transferred our knowledge for the MBE growth of III-V heterostructures layers and (NWs) and deposition of high-k dielectrics using ALD. The potential of the new MBE systems have been demonstrated by the relative fast progress in the growth of high mobility GaAs/AlGaAs heterostructures and the growth control of single InAs NWs on SiOx/Si (111) substrates processed with an original recipe. Step by step, we started to study the growth/deposition processes which finally will permit us to get the suitable in-situ grown structures to reach our goals. Successful experiments have been carried out for the growth of Te doped InAs NWs. Good quality InAs/GaSb NW arrays have been grown with undoped and C doped GaSb shells. The deposition of TaN layer for metal gates has been studied and optimized in the metal MBE system attached to the cluster tool. Hybrid superconductor/semiconductor NW structures combining Al or Nb with InAs were in situ obtained for basic research of novel quantum phenomena, e.g., Majorana fermions, coupling of spin qubits, transmon-like devices, to this end the facility also supporting work pursued by PGI-11.