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Graphene is a monolayer material comprised of sp2 bonded carbon atoms that form a honeycomb-like lattice structure. Because it is only one atom thick, it is the prototypical two-dimensional material and, as such, exhibits unique physical properties, including a high intrinsic mobility (200,000 cm2/Vs) (1) and a constant optical absorption of 2.3% per layer over a wide spectral range (2). Graphene was first isolated physically by the mechanical exfoliation method (3); however, recent efforts have focused on graphene synthesis by conventional methods, such as chemical vapor deposition (CVD) and ultrahigh vacuum, high temperature annealing (i.e., epitaxial graphene from SiC) (4, 5). CVD, in particular, is a promising growth technique because of the ability to deposit large areas of graphene on inexpensive, transition metal materials (e.g., nickel and copper)., The original document contains color images.

A large program in graphene-based nanoelectronics has been initiated at the U.S. Army Research Laboratory (ARL) under the auspices of the ARL Director's Strategic Initiative (DSI). An array of capabilities for graphene growth, characterization, device fabrication, and device modeling has been established, and expertise has been gained in all facets of the research. Significant results have been achieved, including the world's highest reported fT for a graphene field-effect transistor (GFET) fabricated from chemical vapor deposition (CVD)-grown graphene; and a first-generation graphene-based supercapacitor. This research could potentially have enormous benefits for the American Soldier including smaller and more efficient power electronics and communication systems, transparent and flexible electronics, and wearable electronics., The original document contains color images.

Schottky diodes using single wall carbon nanotubes (SWNTs) were fabricated using palladium and aluminum source and drain contacts, respectively. SWNTs were grown on high resistivity silicon substrates with a thermal oxide layer using chemical vapor deposition and ferric nitrate catalyst. Multiple cleanroom processing steps were used to make the diodes which included the deposition of marker layers, oxygen plasma etch for selective nanotube removal, and electron beam evaporation of metal electrodes in two separate depositions. The diodes were designed in a coplanar waveguide (CPW) transmission line topology in order to facilitate RF testing. Electrical testing at the DC level was accomplished. Further investigation into the RF characterization of carbon nanotubes will allow for the incorporation of such devices into integrated circuit architectures., The original document contains color images.