Bagheri, ShahinShahinBagheriZgrabik, Christine M.Christine M.ZgrabikGissibl, TimoTimoGissiblTittl, AndreasAndreasTittlSterl, FlorianFlorianSterlWalter, RamonRamonWalterDe Zuani, StefanoStefanoDe ZuaniBerrier, AudreyAudreyBerrierStauden, ThomasThomasStaudenRichter, GuntherGuntherRichterHu, Evelyn L.Evelyn L.HuGiessen, HaraldHaraldGiessen2026-03-112026-03-112015-01-01Optical Materials Express 5 (11): 2625-2633 (2015)https://hdl.handle.net/11420/62003Robust plasmonic nanoantennas at mid-infrared wavelengths are essential components for a variety of nanophotonic applications ranging from thermography to energy conversion. Titanium nitride (TiN) is a promising candidate for such cases due to its high thermal stability and metallic character. Here, we employ direct laser writing as well as interference lithography to fabricate large-area nanoantenna arrays of TiN on sapphire and silicon substrates. Our lithographic tools allow for fast and homogeneous preparation of nanoantenna geometries on a polymer layer, which is then selectively transferred to TiN by subsequent argon ion beam etching followed by a chemical wet etching process. The antennas are protected by an additional Al2O3> layer which allows for high-temperature annealing in argon flow without loss of the plasmonic properties. Tailoring of the TiN antenna geometry enables precise tuning of the plasmon resonances from the near to the mid-infrared spectral range. Due to the advantageous properties of TiN combined with our versatile large-area and low-cost fabrication process, such refractory nanoantennas will enable a multitude of high-temperature plasmonic applications such as thermophotovoltaics in the future.en2159-393020151126252633Technology::600: TechnologyJournal Article10.1364/OME.5.002625Journal Article