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The resistivity scaling of copper (Cu) interconnects with decreasing dimensions remains a major challenge in the downscaling of integrated circuits. Molybdenum phosphide (MoP) is a triple-point topological semimetal (TSM) with low resistivity and high carrier density. With the presence of topologically protected surface states that should be defect-tolerant and electron backscatter forbidden, MoP nanowires have shown promising resistivity values compared to Cu interconnects at the nanometer scale. In this work, using template-assisted chemical vapor conversion and standard fabrication techniques that are industry-adoptable, we report the fabrication of porous but highly crystalline MoP narrow lines with controlled sizes and dimensions. We examine the influence of porosity, thickness, and cross-section area on the resistivity values of the fabricated MoP lines to further test the feasibility of MoP for interconnect applications. Our work presents a facile approach to synthesizing TSM nanowires with different dimensions and cross sections, enabling experimental investigations of their predicted unconventional resistivity scaling behavior. Finally, our results provide insight into the effects of porosity on the resistivity of these materials on the nanometer scale. 

With shrinking dimensions in integrated circuits, sensors, and functional devices, there is a pressing need to develop nanofabrication techniques with simultaneous control of morphology, microstructure, and material composition over wafer length scales. Current techniques are largely unable to meet all these conditions, suffering from poor control of morphology and defect structure or requiring extensive optimization or post‐processing to achieve desired nanostructures. Recently, thermomechanical nanomolding (TMNM) has been shown to yield single‐crystalline, high aspect ratio nanowires of metals, alloys, and intermetallics over wafer‐scale distances. Here, TMNM is extended for wafer‐scale fabrication of 2D nanostructures. Using In, Al, and Cu, nanomold nanoribbons with widths < 50 nm, depths ≈0.5–1 µm and lengths ≈7 mm into Si trenches at conditions compatible is successfully with back end of line processing . Through SEM cross‐section imaging and 4D‐STEM grain orientation maps, it is shown that the grain size of the bulk feedstock is transferred to the nanomolded structures up to and including single crystal Cu. Based on the retained microstructures of molded 2D Cu, the deformation mechanism during molding for 2D TMNM is discussed.