在矽波導的波長分波多工器中，我們設計以一對四串接的馬赫詹德干涉儀為主，其體積小而且容易積體化形成光纖通訊系統。由於方向耦合器(Directional Coupler, DC)在非中心之波長，其分光比會偏離，造成波長分波多工效果出現串擾(Crosstalk)的落差，因此多工器是由不同分光比的馬赫詹德方向耦合器和相位延遲組成。其中馬赫詹德耦合器相位在分光比對波長不敏感中，扮演非常重要的角色，因此我們將深入討論馬赫詹德方向耦合之相位及其改善的方法，最後將應用在分波複用器中。
本論文設計與製做出具有平頂帶寬的馬赫詹德延遲干涉儀，我們以分光比分別為0.5、0.29和0.08之寬頻馬赫詹德方向耦合器(Mach-Zehnder Directional Coupler, MZDC)組成串接型波長濾波器(Cascaded Wavelength Filter)，並且深入探討MZDC其耦合(Coupled)與非耦合(Decoupled)區相位所造成的影響，避免因彎曲相位導致寬頻分光比的異常。

In the silicon based wavelength division multiplexer (WDM) filter, a cascaded Mach-Zehnder interferometer (MZI) with one input and 4 outputs will demonstrate a small footprint and ease to be integrated to construct a fiber-optic communication system. Since the directional coupler (DC) splitting ratio at the central wavelength will deviate from other wavelength range and cause a serious crosstalk in WDM, the MZI based WDM filter will be formed through Mach-Zehnder directional coupler (MZDC) with different splitting ratios and phases. The MZDC power divider is wavelength independence after the appropriate phase arrangement. Therefore, the related phase and its improvement will be further discussed and applied in the WDM filter.
We designed and fabricated a Mach-Zehnder based delay interferometer with flat top passband. A broadband MZDC with splitting ratios of 0.5, 0.29 and 0.08 will be utilized to form a cascaded wavelength filter. The effects from the phase of the coupled and uncoupled regions of the MZDC is going to be further explored to avoid the broadband splitting ratio deviation.

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