絕緣層上覆矽波導的高折射率差，使具高效率與高品質的特性且成本低，加上其相容於金屬氧化物半導體標準製程，故常廣泛應用於高速、低功耗光電元件。此外，矽與埋藏氧化層之間的高折射率差，使得元件能縮至次微米等級，故以次微米矽線波導設計之環形共振腔可具高積體化光路與易操控自由頻譜範圍(Free Spectral Range, FSR)，常被作為光通訊元件。
在微波工程中，典型的電相位陣列通常會需要數個相位偏移器來達成，而光學元件提供了小尺寸、大頻寬與快速可調性等優點，故常被運用在相位偏移器上，有助於相位陣列之微小化。因此近年來，積體化的絕緣層上覆矽微環形共振腔，常被用來作為相位的偏移器。本論文使用多模干涉器(Multimode Interference)取代方向耦合器(Directional Coupler)作為環形共振腔的耦合元件。雖然多模干涉器的光波損耗較高，但對於波長與耦合率的影響較小，能在較大的頻寬下維持穩定帶寬，因此作為耦合的原因之ㄧ。在此我們設計不同環長的環形共振腔，並改變特定極化偏振，產生不同的自由頻譜範圍與品質參數(Quality Factor)，並在矽波導上沉積金屬鈦作為微型可調加熱器與控制傳輸的調變訊號，同時觀察相位與傳輸變化。
對製作出的多模干涉器元件，理想上為50:50的分光比，實驗數據顯示TE極化時之分光比為56 : 44，TM極化時分光比為54 : 46，同時微型可調加熱器對多模干涉器的影響將一併討論。為瞭解極化有關的相位影響，低同調干涉測得矽線波導的雙折射係數為0.27。最後我們成功以微波光電為基礎製作了相位偏移器，相位偏移量可達到350度左右。

A silicon-on-insulator platform based optical waveguides with large refractive index provides high efficiency, high quality, low cost and its fully compatible processing with the complementary metal-oxide-semiconductor (CMOS) standard process. For these reasons, it is extensively utilized for both of high-speed and low power consumption optoelectronic devices. Moreover, the large refractive index difference between silicon and silicon dioxide layers can significantly reduce the device form size to submicron scale. Therefore, the silicon wire based optical ring resonator owns the potential of the highly integrated optical circuit and easy manipulation on the free spectral range (FSR) in optical communications.
In Microwave Engineering, the electrical phased array is typically composed by numerous phase shifters. However, the photonics, offering many advantages on the compact size, large bandwidth, and fast tunability, was then made into small footprint phase shifters. In this thesis, even though the multimode interference (MMI) owns the higher propagation loss compared with the directional coupler, MMI was still utilized as the coupling function in the silicon-on-insulator (SOI) microring resonator phase shifter due to its wavelength independent spectrum. Several different lengths of optical rings, matched to FSR and quality factor were designed, fabricated, and demonstrated for phase shifting applications. Titanium was deposited on silicon wire optical ring resonator to study the variations on phase and transmission.
The theoretical power splitting ratio of MMI was 50:50. The experimental data were showing the power splitting ratios were 56:44 and 54:46, respectively, for TE and TM polarization. The thermal effect on MMI was also discussed using the deposited titanium. To fully understand the polarization dependent phase, a 0.27 birefringence of silicon wire was observed by the optical low coherence interferometer. Finally, the 350-degree phase shifting was successfully demonstrated on the optical ring resonator for microwave photonics applications.

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