Title:  Optical Coupler Design and Experimental Demonstration for 2.5D/3D Heterogeneous Integrated Electronics

Committee:

Dr. Muhannad Bakir, ECE, Chair , Advisor

Dr. Thomas Gaylord, ECE, Co-Advisor

Dr. Stephen Ralph, ECE

Dr. Benjamin Klein, ECE

Dr. Oliver Brand, ECE

Dr. Suresh Sitaraman, ME

Abstract:

The objective of the dissertation is to theoretically design and experimentally demonstrate optical couplers for 2.5D/3D heterogeneous integrated electronics. In the first part, a new concept, the "equivalent index slab (EIS)" method, is proposed to extend the application of the rigorous coupled-wave analysis (RCWA) to the rectangular grating diffraction phenomena involving surface waves. The RCWA-EIS method can be applied to optimize rectangular grating couplers with arbitrary profiles and to analyze the effects of angular misalignments on the coupling efficiency. In the second part, a fundamentally new coupling structure, the grating-assisted-cylindrical-resonant-cavities (GARC) interlayer coupler, is introduced. Based on cylindrical resonant cavities, the GARC couplers exhibit wider spectral bandwidth and higher coupling efficiency, which are promising alternatives to the conventional couplers. In the third part, a passive self-alignment and assembly approach for optical fibers is proposed and demonstrated using a combination of silicon micromachining and 3D printing to achieve efficient and accurate near-vertical coupling to a photonic chip.