الفهرس 
BACKGROUND AND LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
This thesis aims to study the development of ultra-wide band mid-infrared (MIR) Fourier Transform Infrared (FTIR) spectrometer based on microelectromechanical systems (MEMS) technology and its applications in attenuated total reflection (ATR) sampling method. The spectrometer’s core engine is a Michelson interferometer micro-fabricated on a single silicon chip. Different aspects related to the MEMS spectrometer spectral range are investigated. Silicon absorption and dispersion effects are modelled based on extracted optical constants of silicon wafers. Demonstration of gas sensing, lubricant oil and food analysis applications has been achieved up to wavelength of 9 µm using different IR sources and detectors.
Then, a novel ATR spectrometer is presented. The ATR sampling method is based on multiple reflections of light inside a high refractive index internal reflection element (IRE) allowing evanescent field to penetrate through the sample, which is in direct contact to the IRE. The transmittance is modelled for different types of excitations and compared to experimental results for different liquid samples. Finally, an integrated ATR spectrome-ter is proposed, where the IRE is micromachined on a silicon chip using deep-reactive-ion-etching (DRIE). Micro IREs are fabricated and characterized showing the ability of the proposed design for performing spectroscopic measurements. The device is compatible with microfluidics, where liquids flow inside micro-sized channels beside ATR IREs. The effect of sidewall roughness on the obtained ATR spectrum is theoretically modelled using ray-matrix method and compared to experimental results.