Pulsed-laser dry printing of noble-metal microrings with a tunable internal porous structure, which can be revealed via an ion-beam etching post-procedure, was demonstrated. Abundance and average size of the pores inside the microrings were shown to be tuned in a wide range by varying incident pulse energy and a nitrogen doping level controlled in the process of magnetron deposition of the gold film in the appropriate gaseous environment. The fabricated porous microrings were shown to provide many-fold near-field enhancement of incident electromagnetic fields, which was confirmed by mapping of the characteristic Raman band of a nanometer-thick covering layer of Rhodamine 6G dye molecules and supporting finite-difference time-domain calculations. The proposed laserprinting/ion-beam etching approach is demonstrated to be a unique tool aimed at designing and fabricating multifunctional plasmonic structures and metasurfaces for spectroscopic bioidentification based on surface-enhanced infrared absorption, Raman scattering and photoluminescence detection schemes.Surface-enhanced Raman scattering (SERS) is an ultra-sensitive non-invasive spectroscopic technique based on a label-free identification of different molecules placed in the vicinity of plasmonic-active nanostructured metallic substrates 1-4 . Intensity of the characteristic Raman signal defining the specific vibrational signatures of individual molecules is usually very weak. However, this signal can be significantly increased near nanotextured surfaces or nanostructures generating localized, strongly enhanced plasmon-mediated electromagnetic fields. Since the first observation of SERS signal from single molecule 5 , multiple attempts were undertaken to increase the efficiency of SERS-active nanotextured substrates in terms of achieved maximal enhancement factor inside a single "hot spot" as well as number (density) of "hot spots" per individual nanostructure 6-11 .To address both issues, variety of nanotextured structures, predominantly having large surface-to-volume ratio and generating dense hot spots (tipped structures, nanostructures with inner porosity, intra-gap structures or self-assembly superstructures, etc.) were fabricated and tested as versatile SERS substrates 12-23 . Specifically, porous materials, nanostructures and nanoparticles, routinely reaching uniform SERS enhancement sufficient to overcome single-molecule detection limit independently on excitation/detection conditions, are of growing interest [24][25][26] . Several papers reported fabrication of such sponge-like structures, using dealloying of the two-component template via its dissolving in a corrosive environment 27,28 . Meanwhile, to design sensitive elements for advanced biosensors, along with desirable porosity, it is also important to control the overall size and shape of such porous templates as well as to arrange them into well-ordered arrays at specific point on a substrate with micrometer-scale lateral accuracy. Despite the latter issue can be resolved by using well-establis...

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