矽光子積體電路具有低功耗、低封裝複雜度、可積體化等優點。近年來，隨著自動駕駛汽車的快速發展，對高解析度光學傳感器的需求越來越大。利用矽光子技術實現的全固態光學雷達 (LIDAR) 擁有高解析度、精小和高可靠性的優勢。
在本實驗室先前的研究中，設計了週期性側壁光柵結構波導作為光學天線，利用比利時微電子研究中心提供的矽光子製程成功實現了64通道光學天線陣列。在對此光學天線陣列的性能進行測量與分析後，觀察到製程誤差會導致每根天線的具有不等量的相位誤差。從光學天線陣列所發射出的光束形成的遠場將具有多個光斑，這將嚴重降低遠場光束相位控制之性能。
本論文設計了最佳化的方法來修正製程中產生的天線相位誤差。對於週期性的光學天線陣列，透過利用對每根天線的相位補償來抑制主瓣附近的旁瓣。本論文提出之天線群體相位校正的方法，不僅可以大幅地降低運算時間，並且有效均勻分散旁瓣的能量使光束相位控制之性能提高。經優化後之均勻64根天線光學天線陣列的峰與旁瓣比(Peak to Side Lobe Level, PSLL)為16.74 dB，半峰全寬 (Full Width at Half Maximum, FWHM)為0.16度。
由於週期性的光學天線陣列會使光束轉向角受到兩旁柵瓣的限制。為了解決這個問題，本論文使用相同的最佳化方法設計非週期性光學天線陣列。為了滿足天線線寬的製程限制，天線的間距設計介在2.2 μm到 6.6 μm的範圍內。非週期性的光學天線陣列可以有效的抑制柵辦，提升光束的轉向範圍。經優化之PSLL在補償相位0π時為12.01 dB，補償相位π 時為11.89 dB，而一側之最大轉向角可以擴展至52.7度。新設計的非週期性光學天線陣列，不僅可以滿足半導體代工設計規則的限制，還可以增加光束轉向控制範圍，並已成功下線此設計。

Silicon photonics integrated circuits have the advantages of low power consumption, reduced packaging complexity, and high integration density. Nowadays, with the rapid development of autonomous vehicles, the demand for high-resolution optical sensors is growing. The implementation of solid-state light detection and ranging (LIDAR) systems with silicon photonics technology offers the advantages of high resolution, compactness, and high reliability.
In the prior work of our laboratory, a periodic sidewall grating waveguide structure was designed to form an optical antenna, and a 64-channel optical phased array (OPA) is successfully carried out using the silicon photonic process provided by the commercial foundry. After measuring and analyzing of the OPA performance, it is observed that the fabrication error will cause the phase fluctuation of each antenna. The emitted far field pattern from the OPA will have multiple speckles that will severely degrade the beam steering performance.
We develop the optimization scheme to counter the phase errors from the fabrication process. For uniform OPAs, we aim to suppress the side lobes speckles beside the main lobe by exploiting a phase compensation at each antenna. The method of group phase correction proposed in this work can not only significantly reduce the computation time, but also effectively suppress the side lobe energy. In addition, it enhances the performance of the phase control. The peak to side lobe level (PSLL) for uniform 64-antenna OPAs after the phase correction is 16.74 dB and the full width at half maximum (FWHM) is 0.16 degree. Since the grating lobes of the uniform optical phased array are periodic, the steering angle will be limited by the grating lobes. In order to solve this problem, the aperiodic OPAs were designed using the same optimization algorithm. The antennas can be spaced in the range of 2.2 μm to 6.6 μm to meet the fabrication limitation on the linewidth and gaps for the antennas patterns. The aperiodic optical phased array can efficiently suppress the grating lobes and broaden the beam steering angle. The optimized PSLL is 12.01 dB at 0π phase shift and 11.89 dB at π phase shift. The maximal steering angle is approximately 52.7 degree on one side.
The newly designed OPAs with aperiodic antenna arrangement can not only meet the requirements of semiconductor foundry design rules, but also increase the beam steering range. The design was successfully tapped out for manufacturing.

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