الفهرس 
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Abstract
Silicon-air multilayer structures (highly reflective mirrors in IR), fabricated by the deep reactive ion etching (DRIE) over silicon wafers, have gained high interest in a wide range of applications. The main feature of these structures is that they are vertically etched; allowing them to be used in vertical (i.e in-plane) arrangement. This is opposite to the traditional out-of-plane multilayers fabricated by thin film deposition. The in-plane configuration allows a monolithic integration of these multilayers (i.e. micro Bragg mirrors and Bragg mirrors based Fabry-Perot filters) with many useful components such as optical fiber grooves, microfluidic systems and microelectromechanical (MEMS) actuators. This, in turn, facilitates the production of highly compact integrated devices. However, the previously reported devices were found to encounter high insertion losses. These losses are translated, in many cases, into a lack of optical performance (e.g broadening of the transmission bandwidth in either Bragg mirrors or Fabry-Perot (FP) cavities constructed by Bragg reflectors). The objective of this work is to investigate the technological limitations and the effect of different sources of losses on the performance of the deep etched Bragg mirrors as well as the FP filters that are composed of the deep etched Bragg mirrors. The expected loss results from Gaussian beam divergence is investigated using the expansion method. In addition, a theoretical model to account for the effect of the surface roughness (as a source of loss) in the multilayered structures is provided. The model (combined of losses due to a Gaussian beam divergence and a surface roughness) is verified versus both a standard tool built on finite difference time domain technique (FDTD) and the experimental results. Furthermore, a theoretical approach to account for the effect of the layers non-verticality (as a cause of loss) is provided and compared to FDTD results. For reasonable small etching angles, the surface roughness and Gaussian beam divergence losses will dominate the other sources of loss. The losses result from either any type of misalignments between the input and output fibers or due to a truncation of the Gaussian beam by the finite size structures are also discussed.