本論文中之具極化控制之光學探針，主要想法為達成邊緣耦合器晶圓級量測，探針卡為晶圓級量測中光纖與待測物之間的橋梁，探針卡將以CMOS製程以及SOI wafer為基礎製作，以矽-氮化矽雙層異介質波導為基礎設計元件，利用兩異介質材料組成的二維光柵耦合器與待測物的邊緣耦合器進行耦光，此雙層二維光柵耦合器以垂直收發光源為目標，藉由設計兩層光柵之間的位移、填充率(duty cycle)以及週期，使朝向基板的一階繞射與二階繞射(反射)達成破壞干涉條件，減低了光柵耦合器垂直晶面出射時造成的多階繞射損耗；探針卡的另一端則使用錐形漸變式邊緣耦合器(inverted taper coupler)與光纖陣列封裝；兩端口之間利用選擇器控制光學路徑，進而達到極化控制的效果，光柵耦合器由Lumerical粒子群演算法優化效率，再經過漸變式光柵填充率使能量分布吻合待測物。
在量測結果中，一維光柵耦合器插入損耗為5.2dB，二維光柵光柵耦合器插入損耗為10.83dB，最後以矽光子晶片為待測物，成功實現晶圓級探針卡量測。

In this thesis, we plan to develop an optical probe card to test on-wafer multiple Si photonics devices through edge coupling. The probe card can control the polarization of launched wavelength and detected wavelength for individual devices, respectively. It is made on silicon-on-insulator (SOI) substrate through a CMOS-compatible process On the optical probe card, there are 2D grating couplers composed of two dielectric grating layers to couple light to the edge couplers of the tested devices. By designing the dimensions of the two layers of gratings, the first-order and second-order diffractive lights (reflection) can be cancelled due to destructive interference, which increase the power of vertical coupling. The other end of the probe card is packaged with an optical fiber array connector. A switch is used to control the optical path between the two ports to select different polarizations. We use Lumerical FDTD to design one-dimensional and two-dimensional grating couplers, MMI and edge couplers. The devices are fabricated Taiwan Semiconductor Research Institute (TSRI). We use E-beam lithography to pattern small lines of the grating couplers and use i-Line stepper to pattern the other large-area components. Finally, we do the device measurement and packaging in TSRI and our lab.
The measurement results show the insertion loss of the 1D grating coupler is 5.2dB, and the insertion loss of the 2D grating coupler was 10.83dB. The wafer-level probe card setup was also successfully demonstrated.

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