近年來隨著自駕車的發展，對於感測元件的需求與研究日益增加，利用矽光子技術實現全固態式光學雷達同時具備矽光子積體電路低功耗、可積體化的特性及全固態式光學雷達高解析度、掃瞄範圍大的優點，因此，在感測領域扮演關鍵的技術。
本論文設計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所提供之矽光子製程成功實現64通道光學相控陣列。經過量測與分析，驗證週期性側壁光柵結構波導作為光學天線的可行性，其光學天線傳播方向的光束發散角為0.15°，中心波長1550 nm之光束角度為0.43°，波長調控效率為每奈米0.16°，而光學天線陣列在陣列方向的光束發散角為0.135°，旁瓣角度約為9.66°，以上量測結果與模擬結果相符，但光學天線均勻出光的量測結果與模擬有所差異，其原因為製程誤差導致光柵形狀改變影響出光率。
此外，本論文重新設計光學相控陣列之架構，利用光切換器實現1024通道分組切換之光學相控陣列，不僅解決製程密度規範限制光學天線間距的問題，同時增加波長掃描範圍，並成功下線此設計。

In recent years, the demands of optical sensing devices and the research on the related technologies are fast increasing for developing autonomous vehicles. Implementation of solid-state light detection and ranging (LIDAR) with silicon photonics technology has the advantages of low power consumption, high-density integration, high resolution, and large beam-steering range. Therefore, solid-state LIDARs becomes the key technology in the field of optical sensing.
This thesis aims to design a periodic sidewall grating structure waveguide as an optical antenna for developing a LIDAR chip and implement a 64-channel optical phased array (OPA) on the silicon-on-insulator (SOI) platform by using the multi-project-wafer (MPW) service provided by IMEC. After measurement and performance analysis, the feasibility of using the periodic sidewall grating structure waveguide as an optical antenna is verified. The divergent angle of the optical antenna is 0.15 degrees along the longitudinal direction, the beam angle is 0.43 degree at the center wavelength of 1550 nm, the wavelength-tuning steering efficiency is 0.16 degrees per 1 nm of wavelength shift, the divergent angle of the optical antenna array is 0.135 degrees along the horizontal direction, and the side lobe angle of the optical antenna array is about 9.66 degrees. The above measurement results are consistent with the simulation results. However, the measured light emission pattern for the optical antenna is different from the simulation. The major cause is from the fabrication error that changes the shape of the grating and affect the light emission rate.
In addition, we redesigned the architecture of an OPA by using optical switches to realize a 1024-channel switched OPA which can not only overcome the limitation set by the design rules of the MPW service on the minimal pitch that can be used between the optical antennas, but also increase the steering range of wavelength-tuning on the longitudinal direction. The new design was successfully taped out to IMEC for manufacturing.

[1] J. W. Goodman, Introduction to Fourier Optics, 2nd ed. New York: McGraw Hill Higher Education, 1996.
[2] L. B. Soldano, and E. C. M. Pennings, “Optical multi-mode interference devices based on self-imaging: principles and applications,” Journal of Lightwave Technology, vol. 13, no. 4, pp. 615-627, April 1995.
[3] L. W. Chung, S. L. Lee, and Y. J. Lin, “Principles and application of reduced beat length in MMI couplers,” Optics Express, vol. 14, no. 19, pp. 8753-8764, September 2006.
[4] S. W. Chung, H. Abediasl, and H. Hashemi, “A Monolithically Integrated Large-Scale Optical Phased Array in Silicon-on-Insulator CMOS,” IEEE Journal of Solid-State Circuits, vol. 53, no. 1, pp. 275-296, January 2018.
[5] M. Zadka, Y.-C. Chang, A. Mohanty, C. T. Phare, S. P. Roberts, and M. Lipson, “On-chip platform for a phased array with minimal beam divergence and wide field-of-view,” Optics Letters, vol. 26, no. 3, pp. 2528-2534, 2018.
[6] 楊家亘,“利用矽光子技術實現八通道分波多工器與光學天線設計”,國立臺灣科技大學碩士論文,2019.
[7] D. N. Hutchison, J. S., Jonathan, K. Doylend, R. Kumar, J. Heck, W. Kim, C. T. Phare, A. Feshali, and H. Rong,” High-resolution aliasing-free optical beam steering,” Optica, vol. 3, no. 8, pp. 887-890, August 2016.
[8] D. Kwong, A. Hosseini, J. Covey, Y. Zhang, X. Xu, H. Subbaraman, and R. T. Chen1, “On-chip silicon optical phased array for two-dimensional beam steering,” Optical Letters, vol. 39, no. 4, pp. 941-944, February 2014.
[9] C. Li, X. Cao, K. Wu, X. Li, and J. Chen, “Lens-based integrated 2D beam-steering device with defocusing approach and broadband pulse operation for Lidar application,” Optics Express, vol. 27, no. 23, pp. 32970-32923, November 2019.
 
[10] P. Wang, G. Luo, Y. Li, M. Wang, F. Meng, W. Yang, H. Yu, X. Zhou, Y. Zhang, and J. Pan, “Two-dimensional Large-angle Scanning Optical Phased Array with Single Wavelength Beam,” Conference on Lasers and Electro-Optics (CLEO), May 2019, San Jose, California United States.
[11] Y. C. Chang, M. C. Shin, C. T. Phare, S. A. Miller, E. Shim, and M. Lipson, “Metalens-enabled low-power solid-state 2D beam steering,” Conference on Lasers and Electro-Optics (CLEO), May 2019, San Jose, California United States.
[12] Y. Kane, “Numerical solution of initial boundary value problems involving maxwell's equations in isotropic media,” IEEE Transactions on Antennas and Propagation, vol. 14, no. 3, pp. 302-307, May 1966.
[13] Z. Zhu, and T. G. Brown, “Full-vectorial finite-difference analysis of microstructured optical fibers,” Optics Express, vol. 10, no. 17, pp. 853-864, August 2002.
[14] C. V. Poulton, M. J. Byrd, P. Russo, E. Timurdogan, M. Khandaker, D. Vermeulen, and M. R. Watts,” Long-Range LiDAR and Free-Space Data Communication with High-Performance Optical Phased Arrays,” IEEE Journal of Selected Topics in Quantum Electronics, vol. 25, no. 5, September / October 2019.
[15] C. S. Im, B. Bhandari, K. P. Lee, S. M. Kim, M. C. Oh, and S. S. Lee, “Silicon nitride optical phased array based on a grating antenna enabling wavelength-tuned beam steering,” Optics Express, vol. 28, no 3, pp. 3270-3279, February 2020.
[16] C. Li, X. Cao, K. Wu, X. Li and J. Chen, “A Switch-based Integrated 2D Beam-steering device for Lidar Application,” Conference on Lasers and Electro-Optics (CLEO), May 2019, San Jose, California United States.
[17] H. Zhang, Z. Zhang, C. Peng, W. Hu, “Phase Calibration of On-Chip Optical Phased Arrays via Interference Technique,” IEEE Photonics Journal, vol. 12, no. 2, April 2020.
[18] T. Kim, P. Bhargava, C. V. Poulton, and J. Notaros, A. Yaacobi, E. Timurdogan, C. Baiocco, N. Fahrenkopf, S. Kruger, T. Ngai, Y. Timalsina, M. R. Watts, and V. Stojanovi´c , “A Single-Chip Optical Phased Array in a Wafer-Scale Silicon Photonics / CMOS 3D-Integration Platform,” IEEE journal of solid-state circuits, vol. 54, no. 11, pp. 3061-3074, November 2019. 
[19] S. A. Miller, C. T. Phare, Y. C. Chang, X. Ji, O. A. J. Gordillo, A. Mohanty, S. P. Roberts, M. C. Shin, B. Stern, M. Zadka, and M. Lipson, ”512-Element Actively Steered Silicon Phased Array for Low - Power LIDAR,” Conference on Lasers and Electro-Optics (CLEO), August 2018, San Jose, CA, USA.
[20] M. Raval, C. V. Poulton, and M. R. Watts, “Unidirectional waveguide grating antennas with uniform emission for optical phased arrays,” Optics Letters, vol. 42, no. 13, pp. 2563-2566, 2017.
[21] C. V. Poulton, M. J. Byrd, M. Raval, Z. Su, N. Li, E. Timurdogan, D. Coolbaugh, D. Vermeulen, and M. R. Watts, “Large-scale silicon nitride nanophotonic phased arrays at infrared and visible wavelengths,” Optics Letters, vol. 42, no. 1, pp. 21-24, January 2017.
[22] M. Gehl, G. Hoffman, P. Davids, A. Starbuck, C. Dallo, Z. Barber, E. Kadlec, R. K. Mohan, S. Crouch, and C. Long, “Phase optimization of a silicon photonic two-dimensional electro-optic phased array,” Conference on Lasers and Electro-Optics (CLEO), May 2019, San Jose, California United States.
[23] S. Zhu, T. Hu, Y. Li, Z. Xu, Q. Zhong, Y. Dong, and N. Singh, “CMOS-compatible Integrated Silicon Nitride Optical Phase Array for Electrically Tunable Off-chip Laser Beam Steering,” Electron Devices Technology and Manufacturing Conference (EDTM), Singapore, March 2019.
[24] D. Wu, W. Guo, and Y. Yi, “Compound period grating coupler for double beams generation and steering,” Conference on Lasers and Electro-Optics (CLEO), May 2019, San Jose, California United States.
[25] H. Hashemi, “Large-Scale Monolithic Optical Phased Arrays,” Optical Fiber Communication Conference (OFC), February 2019.
[26] H. Ito, T. Tatebe, H. Abe, and T. Baba, “Wavelength-division multiplexing Si photonic crystal beam steering device for high-throughput parallel sensing,” Optics Express, vol. 26, no. 20, pp. 26145-26155, September 2018.
[27] H. Nikkhah, K. V. Acoleyen, and R. Baets, “Beam steering for wireless optical links based on an optical phased array in silicon,” Annals of Telecommunications, vol. 68, pp. 57-62, February 2013.