Materials Discovery and Interfaces: Projects

Composition and density characterization of transition metal nitride films

The properties of transition metal nitrides (TM-N) strongly depend on their chemical composition (e.g. TM/N ratio) and density. Both, density and composition are affected by synthesis parameters (e.g. temperature, plasma properties). Transition metal nitrides were synthesized by magnetron sputtering using sets of different process parameters. Mechanical properties like Young’s modulus and hardness are determined by nano indentation and residual stress is evaluated by curvature method. The aim of the project is to identify relationships between synthesis parameters, composition and density and mechanical properties. The project is part of the collaborative research center SFB-TR 87.

Quantification of Oxygen, Vanadium and Dopants (M) in V-M-O thin film libraries

VO2 is of interest due to its Semiconductor-to-Metal phase transition. Elmental addition can modulate the transition properties of VO2. To systematically study the effect of elemental doping, V-M-O thin film libraries with continuous composition spread are fabricated by magnetron reactive co-sputtering. The concentration of dopant (M) will be determined by Rutherford backscattering spectrometry (RBS). In addition, it has been reported that the stoichiometry of VOx, e.g., the ratio of oxygen to the metals, can also influence the transition properties. To estimate the amount of oxygen, Nuclear reaction analysis (NRA) will be performed on the libraries.