Development of a complete plasmonic grating-based sensor and its application for self-assembled monolayer detection

Abstract

This work presents an integrated plasmonic biosensing device consisting of a one-dimensional metallic lamellar grating designed to exploit extraordinary transmission of light toward an underlying silicon photodetector. By means of finite element simulations, the grating parameters have been optimized to maximize the light transmission variation induced by the functionalization of the gold nanostructures. An optimized grating was fabricated using an electron beam process and an optoelectronic test bench suitable for sample tests was developed. A clear difference in the grating transmitted light due to surface functionalization was observed in presence of TM polarized illumination.

Optical Interrogation Techniques for Nanophotonic Biochemical Sensors

“…Monolithic integration of nanostructured optical sensors with semiconductor photon detectors is a promising approach for miniaturization as it eliminates the use of external spectrometers and cameras, thus reducing the total footprint [102,103,104,105,106,107]. Frequently, these integrated on-chip sensors are illuminated with an external narrow band light source in a collinear path.…”

“…Nanoplasmonic structures patterned directly on top of photon detector arrays modulate the incident light and the transmitted light is converted into electrical signals on the same device (see Figure 11a). Thus far, various nanoplasmonic structures, including nanodiscs [102,106], nanoholes [103,107] and nanogratings [104,105], have been integrated with numerous photon detectors, such as Si/Ge photodiodes and metal oxide semiconductor (MOS)/CMOS detectors, for intensity interrogation. In order to enhance the sensitivity of an integrated nanoplasmonic system, Guyot et al employed Au NHAs with asymmetric resonance properties.…”

Towards Portable Nanophotonic Sensors

“…Angle sensitive plasmonic nano gratings were also integrated with the bulk silicon photodetector in [71,72]. In [71], Perino et al measured the sensitivity in terms of the change in the transmission intensity of the zero-order diffracted ray of the functionalized and unfunctionalized grating and reported its value as 2.94/RIU, while the detection limit of the integrated sensor was reported to be 2.2 × 10 −4 RIU.…”

“…To transform nanophotonic sensors from laboratory-based demonstrations into practical devices that can be commercialized and used easily in everyday life, it is necessary to develop a compact nanophotonic sensor system, where not only the sensor chip itself, but its readout system is also compact and easy to operate by a non-expert. There have been several efforts to develop on-chip nanophotonic sensors with compact readout systems where researchers have taken different approaches [68,69,70,71,72,73,74,75,76,77,78]. In this article, we will give an overview of the work that has been done to date to develop on-chip nanophotonic sensors with compact readout systems.…”

“…This article is organized as follows; first, the physical phenomena on which nanophotonic sensors operate along with associated performance parameters will be discussed; a brief summary of different types of on-chip nanophotonic sensors made using different materials such as metal (plasmonic), dielectric and semiconductor will then be provided; and finally, an overview of the efforts made so far to miniaturize the readout system of the nanophotonic sensors will be presented. In this review, the sensors having compact readout system are divided into two categories, namely: those where sensors have a monolithically integrated readout system [68,69,70,71,72,73,74,75,76] and those where the readout system is compact but separate to the sensor chip [77,78]. The commonest transducer to capture signals into the electronic domain is a semiconductor photodiode (PD).…”