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Epitaxial graphene (EG) has attracted considerable interest because of its extraordinary properties and ability to be synthesized on the wafer scale. These attributes have enabled EG to be applied in field-effect transistors with extrinsic operating frequencies in the hundreds-of-gigahertz range. Although the quality of EG grown on SiC has improved, there are still obstacles, such as low carrier mobility and large-area thickness nonuniformity, that limit applications in a wide range of truly wafer-scale technologies. In this article, key elements of epitaxial graphene synthesis are highlighted and discussed with regard to impacts on large-area uniformity, structure, and electrical properties. The effects of specific components such as growth-reactor design and substrate quality are examined in an effort to provide a pathway for future advancements in EG production. Finally, key future directions for research in EG are briefly discussed.

This paper reports on the influence of deposition temperature on the structure, composition, and electrical properties of TiO2thin films deposited on n-type silicon (100) by plasma-assisted atomic layer deposition (PA-ALD). TiO2layers ∼20 nm thick, deposited at temperatures ranging from 100 to 300°C, were investigated. Samples deposited at 200°C and 250°C had the most uniform coverage as determined by atomic force microscopy. The average carbon concentration throughout the oxide layer and at the TiO2/Si interface was lowest at 200°C. Metal oxide semiconductor capacitors (MOSCAPs) were fabricated, and profiled by capacitance-voltage techniques. The sample prepared at 200°C had negligible hysteresis (from a capacitance-voltage plot) and the lowest interface trap density (as extracted using the conductance method). Current-voltage measurements were carried out with top-to-bottom structures. At −2 V gate bias voltage, the smallest leakage current was 1.22 × 10−5A/cm2for the 100°C deposited sample.