Surface oxidation as a diffusion barrier for Al deposited on ferromagnetic metalsElectron microscopy study of interfacial reaction between eutectic SnPb and Cu/Ni(V)/Al thin film metallizationThe insertion of chemically vapor deposited graphene layers between Al metallization and Si substrates and between Au and Ni metal layers on Si substrates is shown to provide a significant reduction in spiking and intermixing of the metal contacts and reaction with the Si, where the bilayer graphene was transferred to the samples after the Cu-foil was etched. The graphene prevents reaction between Al and Si up to the temperatures of 700 C and the intermixing of Au and Ni up to the temperatures of at least 600 C. The outstanding performance of the graphene as a metal diffusion barrier will be very useful to improve the stability of the metallizations at elevated temperatures.

Freestanding (suspended) graphene films, with high electron mobility (up to ~200,000 cm 2 V −1 s −1 ), good mechanical and electronic properties, could resolve many of the current issues that are hampering the upscaling of graphene technology. Thus far, attempts at reliably fabricating suspended graphene devices comprising metal contacts, have often been hampered by difficulties in exceeding sizes of 1 µm in diameter, if using UV lithography. In this work, area of suspended graphene large enough to be utilized in microelectronic devices, have been obtained by suspending a CVD graphene film over cavities, with top contacts defined through UV lithography with both wet and dry etching. An area of up to 160 µm 2 can be fabricated as backgated devices. The suspended areas exhibit rippling of the surfaces which simultaneously introduces both tensile and compressive strain on the graphene film. Finally, the variations of the Fermi level in the suspended graphene areas can be modulated by applying a potential difference between the top contacts and the backgate. Having achieved large area suspended graphene, in a manner compatible with CMOS fabrication processes, together with enabling the modulation of the Fermi level, are substantial steps forward in demonstrating the potential of suspended graphene-based electronic devices and sensors.

Conventional semiconductor fabrication methods are unsuitable for manufacturing two-dimensional material-based devices owing to the possibility of material contamination or damage, which significantly affects the device properties. In this study, the self-aligned contact doping method and remote oxygen plasma treatment were used to fabricate a WSe 2 -based topgate field-effect transistor (FET) with minimal contamination and damage. The results of Raman spectroscopy and capacitance−voltage measurement indicated that neither the WSe 2 nor the gate dielectric was damaged by the remote oxygen plasma. Additionally, the current−voltage measurement results exhibited excellent on/off ratio and field-effect mobility. The developed method can be used to fabricate FETs which have significantly high carrier concentrations and derive excellent electrical characteristics from WSe 2 -based devices. Therefore, the proposed process can serve as an effective device manufacturing method in the future.

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The dc characteristics of InAlN/GaN high electron mobility transistors were measured before and after irradiation with 5 MeV protons at doses up to 2 Â 10 15 cm À2. The on/off ratio degraded by two orders of magnitude for the highest dose, while the subthreshold slope increased from 77 to 122 mV/decade under these conditions. There was little change in transconductance or gate or drain currents for doses up to 2 Â 10 13 cm À2 , but for the highest dose the drain current and transconductance decreased by $40% while the reverse gate current increased by a factor of $6. The minority carrier diffusion length was around 1 lm independent of proton dose. The InAlN/ GaN heterostructure is at least as radiation hard as its AlGaN/GaN counterpart. V