Benzene Derivatives Analysis Using Aluminum Nitride Waveguide Raman Sensors

Abstract

Raman spectroscopy using aluminum nitride (AlN) optical waveguides was demonstrated for organic compound analysis. The AlN waveguide device was prepared by reactive sputtering deposition and complementary-metal-oxide semiconductor (CMOS) processes. A fundamental waveguide mode was observed over a broad visible spectrum and the waveguide evanescent wave was used to excite the Raman signals of the test analytes. The performance of the waveguide sensor was characterized by measuring the Raman spectra of the benzene derivative mixtures consisting of benzene, anisole, and toluene. The compositions and concentrations were resolved by correlating the obtained Raman spectrum with the characteristic Raman peaks associated with C−C, C−H, and C−O functional groups. With the advantages of real-time detection and enhanced Raman signal intensity, the AlN waveguides provided a sensor platform for nondestructive and online chemical compound monitoring.

Waveguide-Enhanced Raman Spectroscopy (WERS): An Emerging Chip-Based Tool for Chemical and Biological Sensing

“…In addition to these four common materials, Makela et al [ 59 ] used aluminum nitride (AlN) waveguides fabricated with a CMOS-compatible process for WERS. They chose AIN because it has a suitable refractive index (n = 2.1), and the background can be an order of magnitude lower than silicon nitride in the visible regime.…”

Waveguide-enhanced Raman spectroscopy using visible laser excitation

“…State-of-the-art 300-mm silicon photonics foundries are very particular about the materials permitted in their process flow, which prohibits the use many of the material used for previously reported visible WERS platforms. 12,13 In this work, we compare WERS signal from a sorbent coating 14 at a laser wavelength of 785 nm to WERS at 633 nm using standard, CMOS-compatible waveguide materials and processes.…”

A vapochromic dye/graphene coated long-period fiber grating for benzene vapor sensing

“…For instance, semiconductive benzene sensors operate at high temperature; gas chromatography and mass spectrometry can detect benzene with high sensitivity, but the efficiency is low thus not conducive to real-time and on-site detection. [7][8][9][10][11] There is an urgent need to develop new benzene sensors for practical applications. Innovations in material engineering, such as the study in new sensitive materials, and device engineering such as developing novel sensing structures, both contribute to developing the benzene vapor detection.…”