Effect of fabrication process on contact resistance and channel in graphene field effect transistors.

Contact resistance, as one of the main parameters that limits the performance of graphene-based transistors, is highly dependent on the metal-graphene contact fabrication processes. These processes are investigated and the corresponding resistances are measured based on the transfer length method (TLM). In fabrication processes, when annealing is done on chemical vapor deposition (CVD)-grown graphene samples that are transferred onto SiO/Si substrates, the adhesion of graphene to the substrate is improved, and poly methyl methacrylate (PMMA) residues are also reduced.

Experimental comparison between photoconductive and graphene-based photogating detection in a UV-A region.

Photoconductive detectors that use intrinsic absorbent materials include a wide range of detectors. In this paper, a photoconductive detector is fabricated using a titanium dioxide ( ) thin film. The mechanism of the photodetector is changed to the photogating mechanism by transferring monolayer graphene onto the thin film, which shows a great responsivity with a slight change in the fabrication process.

Experimental comparison between NbO- and TiO-based photoconductive and photogating GFET UV detector.

In the present study, by adding graphene to a photoconductive photodetector with a niobium pentoxide (NbO) absorber layer and exploiting the photogating effect, the responsivity of the photodetector is significantly improved. In this photodetector, the NbO layer detects the light, and the graphene improves the responsivity based on the photogating effect. The photocurrent and the percentage ratio of the photocurrent to dark current of the NbO photogating photodetector are compared with those of the corresponding photoconductive photodetector.

Coulomb Blockade Effect in Well-Arranged 2D Arrays of Palladium Nano-Islands for Hydrogen Detection at Room Temperature: A Modeling Study.

The fast growth of hydrogen usage as a clean fuel in civil applications such as transportation, space technology, etc. highlights the importance of the reliable detection of its leakage and accumulation under explosion limit by sensors with a low power consumption at times when there is no accumulation of hydrogen in the environment. In this research, a new and efficient mechanism is presented for hydrogen detection-using the Coulomb blockade effect in a well-arranged 2D array of palladium nano-islands-which can operate at room temperature.