2026-09-24T02:03:46Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/129670 2026-02-05 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

application/pdf en text Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-05-01 The student, Jaekwon Lee, accepted the attached license on 2025-03-14 at 13:40. The student, Jaekwon Lee, submitted this Dissertation for approval on 2025-03-14 at 14:08. This Dissertation was approved for publication on 2025-03-18 at 14:57. DSpace SAF Submission Ingestion Package generated from Vireo submission #21678 on 2025-10-19 at 19:52:30 Cubic III-Nitrides for photonics: Physics, materials, and devices Lee, Jaekwon 2025-03-18 Bayram, Can Bayram, Can Dallesasse, John Michael Goddard, Lynford L Kim, Kyekyoon Leburton, Jean-Pierre Ploessl, Andreas Eberhard Solgaard, Olav Cubic Nitride Light-emitting diodes green gap eng Light-emitting diodes (LEDs), especially InGaN-based LED devices, have achieved remarkable success in solid-state lighting, contributing to 25 % of energy savings already. However, expected population growth and increasing demand for lighting necessitate a more efficient approach, which can only be realized by solving the issue of the green gap (i.e., the inefficiency of the state-of-the-art green LEDs). Cubic nitride LEDs are proposed as a promising solution to the green gap, due to well-documented advantages in the literature. However, there are theoretical and experimental issues in the current approach that need to be innovated in order to translate these material advantages into functional devices and address the green gap with the cubic nitride approach. In this thesis, the realization of cubic nitride LEDs will be tackled in both theoretical and experimental aspects. First, three crucial design rules specific to cubic nitride LEDs are suggested, enabling highly efficient theoretical stack design. Second, high-quality, phase-pure cubic GaN is demonstrated and characterized as a template for further material growth. Next, purely cubic active layers are synthesized and characterized, showing high enough internal quantum efficiency with green emission to make a functional device. Finally, the LED and micro-LED fabrication based on cubic GaN template are shown, and the characterization of these novel devices is discussed. 2025-05 Thesis https://hdl.handle.net/2142/129670 Copyright 2025 Jaekwon Lee Electrical & Computer Eng Electrical & Computer Engr University of Illinois Urbana-Champaign Ph.D. Dissertation