Analytical performance of μ-groove silicon attenuated total reflection waveguides

Abstract

The analytical performance of micromachined μ-groove silicon attenuated total reflection (ATR) elements has been evaluated in a comparison of Fourier-transform infrared (FTIR) and quantum cascade laser (QCL) spectroscopy operating at mid-infrared (MIR) wavelengths. μ-Groove silicon ATR elements are highly efficient micromachined waveguides fabricated at a wafer scale at such low cost that they may be considered a consumable for single-time-use, e.g., in medical application scenarios. Herein, exemplary analytes haven been used for reliably evaluating their analytical performance (i.e., acetate and carbonate) in terms of sensitivity, noise level, and achievable limits of detection in a comparison of broadband vs. narrowband infrared spectroscopy.