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In this article, we present a refined nanostructuring method, lift-off nanoimprint lithography (LO-NIL), which allows the deposition of high-quality metal nanostructures due to a bilayer resist process and compare it to nano-transfer printing (nTP), a purely additive metal printing technique. LO-NIL and nTP are used as accurate methods for the fabrication of ordered plasmonic metal nanostructure arrays on semiconducting substrates over large areas using the example of gold nanodisks on silicon. The possibility of feature size adjustment in LO-NIL during the fabrication process is especially useful for tuning plasmonic resonance peaks between the visible and the mid-infrared range as well as fine-tuning of these resonances. In UV-VIS-NIR spectroscopic measurements, a significant blueshift in the plasmonic resonance was found for nTP samples compared to the ones fabricated with the lift-off technique. It was concluded that this shift originates from a metal/substrate interface roughness resulting in a chang...

Highly-ordered, sub-70 nm-MOS-junctions of Au/Ti/TiOx/p+-Si were efficiently and reliably fabricated by nanotransfer-printing (nTP) over large areas and their functionality was investigated with respect to their application as MOS-devices. First, we used a temperature-enhanced nTP process and integrated the plasma-oxidation of a nm-thin titanium film being e-beam evaporated directly on the stamp before the printing step without affecting the p+-Si substrate. Second, morphological investigations (scanning electron microscopy) of the nanostructures confirm the reliable transfer of Au/Ti/TiOx-pillars of 50 nm, 75 nm, and 100 nm size of superior quality on p+-Si by our transfer protocol. Third, the fabricated nanodevices are also characterized electrically by conductive AFM. Fourth, the results are compared to probe station measurements on identically processed, i.e., transfer-printed μm-MOS-structures including a systematic investigation of the oxide formation. The jV-characteristics of these MOS-junctions demonstrate the electrical functionality as plasma-grown tunneling oxides and the effectivity of the transfer-printing process for their large-scale fabrication. Next, our findings are supported by fits to the jV-curves of the plasma-grown titanium oxide by kinetic-Monte-Carlo simulations. These fits allowed us to determine the dominant conduction mechanisms, the material parameters of the oxides and, in particular, a calibration of the thickness depending on applied plasma time and power. Finally, also a relative dielectric permittivity of 12 was found for such plasma-grown TiOx-layers.