Large Area Nanohole Arrays for Sensing Fabricated by Interference Lithography

Abstract

Several fabrication techniques are recently used to produce a nanopattern for sensing, as focused ion beam milling (FIB), e-beam lithography (EBL), nanoimprinting, and soft lithography. Here, interference lithography is explored for the fabrication of large area nanohole arrays in metal films as an efficient, flexible, and scalable production method. The transmission spectra in air of the 1 cm2 substrate were evaluated to study the substrate behavior when hole-size, periodicity, and film thickness are varied, in order to elucidate the best sample for the most effective sensing performance. The efficiency of the nanohole array was tested for bulk sensing and compared with other platforms found in the literature. The sensitivity of ~1000 nm/RIU, achieved with an array periodicity in the visible range, exceeds near infrared (NIR) performances previously reported, and demonstrates that interference lithography is one of the best alternative to other expensive and time-consuming nanofabrication methods.

Circular Dichroism in Low-Cost Plasmonics: 2D Arrays of Nanoholes in Silver

“…Their resonant optical response is strongly influenced by the choice of the patterned metal, the materials surrounding it, and the periodicity of the array [4]. The unique coupling and subwavelength confinement properties of nanohole-based plasmonic devices have already led to many demonstrations and application proposals in subwavelength optics [5], surface enhanced Raman spectroscopy [6,7], enhanced fluorescence [8], emission rate modification [9], polarization conversion [10], and, in particular, chemical and biosensing [11][12][13][14][15][16][17].…”

Coupling Single-Drop Microextraction with SERS: A Demonstration Using p-MBA on Gold Nanohole Array Substrate

“…The gold nanohole array substrates (AuNHAS), with period ʌ = 500 nm, were fabricated using a combination of two-beam interference lithography (IL) and a lift-off step. Details of the experimental process can be found in Menezes et al [9]. Briefly: One portion of the wavefront of a spatially filtered laser beam (458 nm) impinged directly incident on the substrate surface, while the other portion was reflected by a mirror toward the sample.…”

“…Gold nanohole arrays of different shapes, sizes, and periodicities have been fabricated by electron beam lithography (EBL) or focused ion beam (FIB), among other techniques, and successfully applied as substrates to monitor rhodamine 6G (Rh6G) dyes and other molecules [7,8]. Interference lithography (IL) was employed here as an alternative fabrication method that provides a convenient approach to generate a reproducible large area AuNHAS (1-inch squared) at lower costs in respect to common serial techniques, such as FIB and EBL [9]. In a general manner, for very low concentration analysis, i.e., below 10 −6 mol L −1 , many nanostructured materials may not be sensitive enough for an efficient detection.…”

Frontiers of light manipulation in natural, metallic, and dielectric nanostructures

“…LIL is a mask-less photolithographic technique used for the fabrication of nanostructures through the superposition of multiple laser beams onto a photoresist [280]. As reported recently by Valsecchi et al [281], this method is well suited to produce on large scale well-resolved plasmonic nanostructures such as gold nanoholes (see Fig. 15) for sensing applications.…”