Investigation of Ohmic Contacts for Gallium Nitride-Based Power Electronic Devices Using Molecular Beam Epitaxy

The main objective of this research is to investigate and develop stable and reproducible low ohmic contacts through careful monitoring of the GaN surface and distribution of dopants while employing SAG by plasma assisted molecular beam epitaxy (PAMBE). The work specifically involved thin film growth, film characterization, device fabrication and device characterization. To develop the SAG technique and study the effect of etchants on single crystal GaN layers during ohmic contact fabrication, surface bonding and surface morphology were examined. Another important phase of this work consisted of achieving the ohmic contact and device performance enhancement with SAG process and interface analysis by cross sectional TEM. The SAG technique was expanded to nonalloyed ohmic contacts proving that the SAG is crucial in fabrication of nonalloyed ohmic contacts. Finally, high electron mobility transistors (HEMTs) were demonstrated for a realistic DC-DC (direct current) converter.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Materials Science and Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Seo, Huichan

Contributors dc:contributor

• Kim, Kyekyoon

• Engineering, Materials Science

Language dc:language

eng

Identifier

(MiAaPQ)AAI3347506

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/82835