自從光電積體電路被廣泛應用之後，就有許多波導材料被提出來，其中又以絕緣層上覆矽(Silicon on Insulator, SOI)最常被使用，因為此種材料有著低成本、高效率、高品質等特性，且絕緣層上覆矽又與互補式金屬氧化物半導體製程相容，在追求體積變小的趨勢下，絕緣層上覆矽因為具有高折射率差，使得元件線寬可以從微米等級縮小至次微米等級，因此用次微米矽線波導所設計的光環型共振腔(Optical Ring Resonator)，被廣泛的運用在光電積體電路中。
在光環型共振腔裡，分光功率器是一個不可或缺的元件，分光功率器不只可以運用在光環型共振腔上，更可以運用於差動相位偏移調變(Differential Phase Shift Keying, DPSK)、光解調變器(Demodulator)、三工器(Triplexer)等地方，最常見的分光功率器有方向耦合器(Directional Coupler, DC)和多模干涉器(Multimode Interference, MMI)。由於方向耦合器的間距(Gap)受到製程上尺寸的限制，所以多模干涉器是最常被運用在光環型共振腔中的分光功率器，多模干涉器對於分光率有著對波長與極化不敏感的特性，但是因為設計方式的關係，多模干涉器通常只有特定的分光率，且多模干涉器的分光率和品質因數在光環型共振腔中是否可以用轉移矩陣(Transfer matrix)的公式來取得正確的關聯，尚存在爭議性，所以本論文提出以馬克詹德方向耦合器(Mach-Zehnder Directional Coupler, MZDC)取代光環型共振腔中的多模干涉器，它是藉由在方向耦合器中間加上一段延遲長度所組成，具有對波長不敏感且任意分光率的特性，運用其任意分光率的優點，來設計光環型共振腔中的品質因數(Quality Factor, Q factor)。
我們在矽線波導上製作出運用馬克詹德方向耦合器的光環型共振腔，我們製作的波導損耗為 ，但是卻有著14090、23871、19388的品質因數，假設未來的波導損耗可以更低的話，我們的品質因數將可以更高，並且可以應用於生醫感測上。

In recent decades, a lot of waveguide materials are proposed to demonstrate the applications for optoelectronic integrated circuits (OEIC). Among them the silicon-on-insulator (SOI) is most commonly used due to its low cost and high compatibility with the complementary metal oxide semiconductor (CMOS) standard process. Moreover, SOI owns a high refractive index difference between the core and cladding layers for a compact size. Then a submicron silicon wire waveguide based optical ring resonator is widely studied and utilized in current OEIC systems.
In addition to the multiple functions of differential phase shift keying (DPSK) optical demodulation and triplexer, the power splitter is an essential element in the optical ring resonator. The most common power splitters are directional coupler (DC) and multimode interferometer (MMI). Due to the processing critical dimension limitation for DC gap distance, MMI is the most popular power splitter in the optical ring resonator. The MMI splitting ratio is insensitive to the wavelength and polarization. However, the relationship between the MMI splitting ratio and quality factor of the optical ring resonator cannot be correlated in theoretical derivation using the transfer matrix function. In this thesis, a Mach-Zehnder directional coupler (MZDC), composed by adding the phase delay length between two DCs, will be presented and demonstrated for wide wavelength operation. MZDC can achieve any splitting ratio, as well as the wavelength-insensitive characteristics.
An optical ring resonator was successfully fabricated and demonstrated with the quality factors of 14090, 23871 and 19388 using silicon wire waveguide based MZDC power splitters. The silicon wire waveguide propagation loss was 33 dB/cm, which can be further improved for even higher quality factors for biosensor applications.

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