絕緣層上覆矽(Silicon-on-Insulator, SOI)是近年來被廣泛應用在高速且低功耗的電子元件上，因為具有高折射率係數可大幅縮小元件體積,同時製作方式與互補式金屬氧化物半導體(Complementary Metal Oxide Semiconductor, CMOS)製程相容，有利於光電積體電路的發展。本文重點為馬克-詹德方向耦合器(Mach-Zehnder Directional Coupler, MZDC)的設計與應用，此元件是由一段短的延遲長度與兩段方向耦合器所組成;馬克-詹德方向耦合器具有任意分光率和波長不敏感的優點。本文會介紹MZDC的分光原理和波長不敏感的原因，並說明此元件如何被應用在環形共振腔(ring resonator)、差動相位偏移調變系統(Differential Phase Shift Keying, DPSK)和色散(Chromatic Dispersion, CD)監測。

Silicon-on-insulator (SOI) has been widely utilized in high-speed, low-power electronics and optoelectronic integrated circuits (OEIC) these few years due to its high refractive index for small footprint and compatible processing with complementary metal oxide semiconductor (CMOS). The optical power coupling ratio and wavelength independence are very crucial functions in optical communications. In this thesis, a Mach-Zehnder directional coupler (MZDC), composed by two directional couplers connected with a short phase delay length, will be demonstrated in theory and experiment for micron and submicron SOI waveguides. MZDC owns the advantage of any splitting ratio and flatted wavelength response. A microring resonator (MRR) with 0.25-m silicon wire thickness and delayed Mach-Zehnder interferometer (MZI) with 5-m waveguide thickness, all constructed by MZDC, will demonstrate the consistent quality factor (Q) and chromatic dispersion (CD) monitoring.

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