▎ 摘　　要

NOVELTY - Forming graphene (1210), involves: placing a substrate in a processing chamber; introducing a cleaning gas including hydrogen and nitrogen into the processing chamber; introducing a carbon source into the processing chamber; initiating a microwave plasma in the processing chamber; and subjecting the substrate to a flow of the cleaning gas and the carbon source for a predetermined period of time. USE - For forming graphene used in graphene structure or nano-switch (all claimed); in nano-electronic, spintronic, and mechanical applications; and in large-area optoelectronic devices such as touch screen displays and electrodes for photovoltaic cells and light emitting diodes. ADVANTAGE - The present method uses a one-step, low-temperature plasma-enhanced chemical vapor deposition (PECVD) process for rapidly producing large-area graphene with superior quality. This scalable process eliminates technological limitations imposed by thermal chemical vapor deposition (CVD) processes, making it amenable for integration with complementary materials and technology. Additionally, the low-temperature (LT)-grown graphene formed using PECVD exhibits a number of unique and excellent properties, including: nearly strain-free graphene sheets over a large area; atomic flatness and excellent crystalline structures over a large area; mechanical integrity upon transfer from the growth copper substrate to other surfaces; a one-step fast growth process (within less than 5 minutes) that is compatible with device fabrication processes; excellent electrical mobility of greater than 60000 cm2/V-s; and large grain sizes of typically greater than 100 mu m, preferably 250-300 mu m in length. Interconnects with the graphene-on-copper configuration provide a number of advantages over existing copper interconnects. First, both the electrical and thermal conductivity of such interconnects can be much improved because graphene is a superb electrical and thermal conductor. Second, the risk of thinning copper interconnects and therefore increasing electrical resistivity and increasing heat dissipation with time due to electron migration can be mitigated because the integrity of the sp2 bonds in graphene will remain intact with time, thus providing a long-lasting conduction path even in the event of failure of the parallel copper conduction path. Photonic crystalline structures can be fabricated by depositing graphene on skeletons of photonic crystalline structures coated with thin films of copper. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a graphene structure comprising: a copper substrate; and a single monolayer of graphene (1210) disposed on the substrate and having a lateral dimension, where the monolayer of graphene has a height variation of less than 5.0x 10-2 nm per unit area of the lateral dimension; and (2) a nano-switch (1200) comprising: a substrate (1230); at least one cavity or nano-dot disposed in the substrate; a graphene monolayer (1210) coupled to the substrate and overlying the cavity or nano-dot; an electron source coupled to the substrate and the graphene layer, where the electron source is configured to inject electrons into the graphene layer; and several electron sinks (1222, 1224, 1226) coupled to the graphene sheet, the electron sinks are configured to receive ballistic electrons passing through the graphene layer. DESCRIPTION OF DRAWING(S) - The figure shows a simplified perspective diagram of a nano-switch. Strain-engineered graphene valley splitting/switching device (1200) Graphene sheet (1210) Triangular hole (1212) Source contact (1220) Grounded wire (1221) Substrate (1230)