β-Mo2N thin films are sintered by thermal annealing of Mo/amorphous Carbon heterostructures.
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They display superconductivity for thickness as thinner as 2–3 nm.
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They exhibit a very sharp transition to a superconducting state.
Abstract
Molybdenum carbide ultrathin thin films are obtained by thermal annealing of molybdenum/amorphous carbon heterostructures. The samples were grown at room temperature by magnetron sputtering on Si (1 0 0). As-grown samples display superconductivity, which could be related to the coexistence of crystalline and amorphous Mo. Interfacial β-Mo2C phase is observed after thermal annealing at 1033 K. Annealed samples display sharp superconducting transitions. A difference in the maximum critical temperature observed in trilayers and multilayers could be related to superconducting coupling between β-Mo2C layers.