• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • Tagged with
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Design and Fabrication of Asymmetric Mach-Zehnder Interferometer and Ring Cavity Filter

Li, Kuan-Jui 10 July 2006 (has links)
The goal of the thesis is to fabricate the integrated asymmetric Mach-Zehnder Interferometer and Optical waveguide Ring Resonator with simple fabrication process. A 1.49£gm symmetric quantum well InGaAlAs epitaxial wafer is used to fabricate the devices. In the asymmetric Mach-Zehnder Interferometer design, we design asymmetric straight waveguides with difference of optical path, and asymmetric bend waveguides with difference of curvature radius. By this design, we can observe the interference variation of output light by difference of optical path. Using these properties, it will get the index change caused by electric field and the loss of bend waveguide. In optical waveguide ring resonator design, we improve the problem of the length of original K=0.15 Multi-Mode Interference (MMI) by stepped-width waveguide. And we obtain different transmission spectrum by adjusting the splitting ratio of MMI couplers (K=0.85, 0.5, and 0.15) and cascading doudle rings. We apply K0=0.5, K1=0.15 and K2=0.5 MMIs to design and fabricate optical filters with square transmission spectrum. In fabrication process, we get smooth sidewall and highly perpendicularity waveguide by multi-step wet etch method. In order to reduce waveguide loss, we make deep etching for the outside of curve waveguide and MMI. Finally, we use polyimide to smooth out the sides of the ridge waveguides and evaporate metal pad over the polyimide.
2

Design and Fabrication of Straight and Curve Optical Waveguides and Ring Cavity Wavelength Filter

Lin, Cheng-Nan 30 July 2007 (has links)
The goal of the thesis is to fabricate the integrated asymmetric Mach-Zehnder Interferometer and optical waveguide ring resonator with simple fabrication process. 1.41£gm and 1.49£gm symmetric quantum well InGaAlAs epitaxial wafer is used to fabricate the devices. In the asymmetric Mach-Zehnder Interferometer , we design asymmetric straight waveguides with difference optical path differences £GL=480£gm, 970£gm, and 1900£gm. And asymmetric bend waveguides with curvature radius differences £GR=260£gm, 200£gm, 160£gm, and 100£gm. By this design, we can observe the interference variation of output light. In optical waveguide ring resonator design, we reduce the length of original K=0.15 Multi-Mode Interference (MMI) by stepped-width waveguide. By three-stepped width waveguide MMI design, it can be reduced 33.2% length. We obtain different transmission spectrum by adjusting the splitting ratio of MMI couplers (K=0.85, 0.5, and 0.15) and cascading doudle rings. We use a series of two ring resonators by MMI (K0=0.5,K1=0.15,K2=0.5) to get the FSR=50GHz. In fabrication process, we combined dry etching method with RIE-ICP and wet etching to get smooth sidewall and highly vertical waveguide. In measure , we get the FSR= 41.25 GHZ in throughput port in double ring filters . No signal in drop port was obserred due to material absorption, bending loss, and waveguide loss.
3

A study of Asymmetric Mach-Zehnder Interferometer and Optical waveguide Ring Resonator

Tsai, Cheng-ju 21 July 2005 (has links)
The goal of the thesis is to fabricate the integrated asymmetric Mach-Zehnder Interferometer and Optical waveguide Ring Resonator with simple fabrication process. A 1.49

Page generated in 0.1292 seconds