Growth of lattice-mismatched iii-phosphide optoelectronic devices by molecular beam epitaxy

Epitaxial growth of high-quality III-V semiconductors that are lattice-mismatched to conventional substrates is vital to device applications such as high-efficiency multi-junction solar cells, LEDs, and laser diodes. Challenges arise due to the formation of defects driven by lattice mismatch that can damage the performance of III-V devices. In this thesis, I describe the growth of high-quality III-P materials by molecular beam epitaxy in lattice-mismatched systems for optoelectronic device applications. My work includes the development of compositionally graded buffers and growth optimization studies to mitigate challenges for lattice-mismatched materials. First, I demonstrate metamorphic 1.7 eV In0.63Ga0.37P front-junction and rear-heterojunction solar cells grown on GaAs substrates that show promise for high efficiency 1.7 eV/1.1 eV double junction solar cells and photovoltaic devices with efficient operation at elevated temperatures. Next, I demonstrate growth of GaP on silicon on insulator (SOI). Nanophotonic devices based on GaP have recently attracted significant interest due to their unique properties such as large refractive index, relatively wide bandgap, and non-centrosymmetric crystal structure, while SOI wafers are commonly used in silicon photonics. Taken together, this dissertation shows the challenges and opportunities of phosphide-based materials and devices grown on lattice-mismatched substrates.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Electrical & Computer Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2023

Author dc:creator

• Kim, Mijung

Contributors dc:contributor

• Lee, Minjoo L
• Bayram, Can
• Dallesasse, John
• Shim, Moonsub

• Lattice-mismatched
• Iii-v
• Epitaxy
• Mbe
• Optoelectronic Devices

Statement dc:rights

• Copyright 2023 Mijung Kim

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/122257

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F122257