TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The step of providing the copper substrate includes providing the first copper layer, cleaning a surface of the first copper layer, depositing the second copper layer on the cleaned surface of the first copper layer to form the copper substrate, and thermally annealing the copper substrate. The surface of the first copper layer is cleaned by one or more of sputter cleaning, acid etching, solvent rinsing, electropolishing or chemical mechanical polishing. The second copper layer is deposited on the surface of the first copper layer by one or more of sputtering, evaporation, electroplating, or chemical vapor deposition. The second copper layer is saturated in dissolved oxygen at the annealing temperature. The thermal annealing includes heating in an atmosphere comprising 1-10 mol.% hydrogen and 90-99 mol.% of one or more noble gases. Preferred Components: The first copper layer further has a first oxygen percentage by weight. The second copper layer further has a second oxygen percentage by weight. The second oxygen percentage is less than or equal to the first oxygen percentage. In a dimension perpendicular to the graphene monolayer, the first copper layer has a first average thickness, the second copper layer has a second average thickness, and the second average thickness is less than the first average thickness. The first average thickness is at least 3 mu m and the second average thickness is one atomic monolayer of copper to 25 mu m. The second copper percentage is: greater than the first copper percentage by at least 0.1%; and at least 99.9%. The first copper percentage is less than 99.9%.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The system further comprises a chemical vapor source configured to provide one or more chemical vapor deposition precursors for forming graphene, where the microprocessor is programmable to employ the chemical vapor source to grow a graphene monolayer at the second copper layer using the chemical vapor deposition precursors for forming graphene. The microprocessor is further programmable to employ the copper deposition source to deposit the second copper layer at a second oxygen percentage by weight that is less than or equal to the first oxygen percentage. EXAMPLE - A sample of 99.8% pure copper was placed in the fused silica tube furnace which is configured as a chemical vapor deposition (CVD) chamber. Hydrogen gas was supplied at 2 standard cc/minute (sccm) and a pressure of 40 milliTorr. The 99.8% copper foil was heated at 1000 degrees C for 45 minutes and the temperature was allowed to stabilize for 15 minutes. Methane was admitted at a flow of 35 sccm to reach a total chamber pressure of 500 milliTorr. The hydrogen flow was continued at 2 sccm. The graphene was allowed to grow on the copper foil for 30 minutes. The CVD chamber was allowed to cool at ambient temperature for 50 minutes and worked up to obtain desired graphene.