Epitaxial Ti3SiC2 (0001) thin film contacts were grown on doped 4H-SiC (0001) using magnetron sputtering in an ultra high vacuum system. The specific contact resistance was investigated using linear transmission line measurements. Rapid thermal annealing at 950 °C for 1 min of as-deposited films yielded ohmic contacts to n-type SiC with contact resistances in the order of 10−4 Ω cm2. Transmission electron microscopy shows that the interface between Ti3SiC2 and n-type SiC is atomically sharp with evidence of interfacial ordering after annealing.

In the present study, gold/surfactant core/shell colloidal nanoparticles with a controlled morphology and chemical composition have been obtained via the so-called sacrificial anode technique, carried out in galvanostatic mode. As synthesized Au-NPs had an average core diameter comprised between 4 and 8 nm, as a function of the electrochemical process experimental conditions. The UVVis characterization of gold nanocolloids showed clear spectroscopic size effects, affecting both the position and width of the nanoparticle surface plasmon resonance peak.The nanomaterial surface spectroscopic characterization showed the presence of two chemical states, namely nanostructured Au (0) (its abundance being higher than 90%) and Au (I) . Au-NPs were then deposited on the top of a capacitive Field Effect sensor and subjected to a mild thermal annealing aiming at removing the excess of stabilizing surfactant molecules. Au-NP sensors were tested towards some gases found in automotive gas exhausts. The sensing device showed the largest response towards NO x , and much smaller -if any-responses towards interferent species such as NH 3 , H 2 , CO, and hydrocarbons.

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and Per Eklund, Phase-stabilization and substrate effects on nucleation and growth of (Ti,V)(n+1)GeC(n) thin films, 2011, Journal of Applied Physics, (110) Phase-pure epitaxial thin films of (Ti,V) 2 GeC have been grown onto Al 2 O 3 (0001) substrates via magnetron sputtering. The c lattice parameter is determined to be 12.59 Å , corresponding to a 50=50 Ti=V solid solution according to Vegard's law, and the overall (Ti,V):Ge:C composition is 2:1:1 as determined by elastic recoil detection analysis. The minimum temperature for the growth of (Ti,V) 2 GeC is 700 C, which is the same as for Ti 2 GeC but higher than that required for V 2 GeC (450 C). Reduced Ge content yields films containing (Ti,V) 3 GeC 2 and (Ti,V) 4 GeC 3 . These results show that the previously unknown phases V 3 GeC 2 and V 4 GeC 3 can be stabilized through alloying with Ti. For films grown on 4H-SiC(0001), (Ti,V) 3 GeC 2 was observed as the dominant phase, showing that the nucleation and growth of (Ti,V) n þ 1 GeC n is affected by the choice of substrate; the proposed underlying physical mechanism is that differences in the local substrate temperature enhance surface diffusion and facilitate the growth of the higher-order phase (Ti,V) 3 GeC 2 compared to (Ti,V) 2 GeC.