矽基片B型抗諧振反射光波導環形共振器之分波多工器的設計、製作與其特性量測

Abstract

由於網際網路的發展，資訊傳輸的需求急速的增加，分波多工器對於光纖傳輸來說是一種可以節省成本及更有效增加傳輸速率的方式。在我的研究裡面分別探討了利用B型抗諧振反射光波導的環形共振器來實現分波多工器的設計、模擬、製作及量測，因為B型抗諧振反射光波導擁有較大的導光核心區，所以能夠有效和單模光纖相匹配。我們利用轉移矩陣法與等效折射係數法分析與設計B型抗諧振反射光波導結構，接著利用二維時域有限差分法模擬B型抗諧振反射光波導環形共振器之分波多工器的傳波特性。芯材及第二層覆蓋層是選用氮化矽，而第一層覆蓋層是選用氧化矽，芯材的厚度是2微米，第二層覆蓋層厚度是1微米，第一層覆蓋層厚度是0.5微米，芯材的寬度為0.5微米，這種結構可以形成單模傳輸，我們設計了四個不同環半徑分別是9.97微米、10.01微米、10.05微米及10.09微米的環形共振器，而環形共振器與直波導的間距是0.6微米，去分別傳輸四個頻道，模擬得到四個頻道分別傳遞1552.55 奈米、1556.74奈米、1560.95奈米、1565.13奈米的訊號，經由量測我們元件的通過端口，得到實際上元件的四個通道分別傳1553.35奈米、1556.78奈米、1559.28奈米及 1562.89奈米，實際上傳遞於通道的訊號波長和模擬的誤差值可以控制在0.1%以下。

In this study, the design, fabrication, and characterization of the Si-based ARROW-B ring resonator for WDM applications were discussed. The ARROW-B waveguide structures had relatively large core sizes for efficient coupling with single-mode fibers in the vertical direction. The characteristics of ARROW-B structure were analyzed with the transfer matrix method and the effective index method. We used the 2D-FDTD (finite-difference time-domain) to simulate the propagation characteristics of the ARROW-B ring resonator for WDM applications. In our designed structure, the core layer and second cladding layer were chosen with the same material of silicon nitride. The thickness of the core layer was 2 μm, and the thickness of second cladding was 1 μm. Silicon oxide was the material of the first cladding layer whose thickness was 0.5 μm. This structure could get a low loss of fundamental mode and large losses for high-order modes. The width of core was 0.5 μm, and the radii of rings were 9.97 μm, 10.01 μm, 10.05 μm, and 10.09 μm, respectively. The gap between the ring and the straight waveguide was 0.6 μm. The simulation results showed that four channels are propagated at 1552.55 nm, 1556.74 nm, 1560.94 nm, and 1565.13 nm. Compared with our measured value of through port at 1553.35 nm, 1556.77 nm, 1559.31 nm, and 1563.03 nm, the deviation of propagation wavelength is lower than 0.1%.