Date of Award
8-2022
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Electrical Engineering
Committee Chair/Advisor
Goutam Koley
Committee Member
William R. Harrell
Committee Member
Pingshan Wang
Abstract
We have investigated photon-assisted trapping and detrapping of electrons injected from the gate under negative bias in a heterostructure field-effect transistor (HFET). The electron injection rate from the gate was found to be dramatically affected by sub-bandgap laser illumination. The trapped electrons reduced the two-dimensional electron gas (2DEG) density at the AlGaN/GaN heterointerface but could also be emitted from their trap states by sub-bandgap photons, leading to a recovery of 2DEG density. The trapping and detrapping dynamics were found to be strongly dependent on the wavelength and focal position of the laser, as well as the gate bias stress time prior to illumination of the HFET. Applying this phenomenon of trapping and detrapping assisted by sub-bandgap photons, red, green, and purple lasers were used to demonstrate photo-assisted dynamic switching operations by manipulation of trapped carriers at the surface of an AlGaN/GaN HFET. A physical model based on band diagrams, explaining the trapping and detrapping behavior of electrons, has been presented.
Recommended Citation
Gunn, Andrew, "Sub-Bandgap Photon-Assisted Electron Trapping and Detrapping in AlGaN/GaN Heterostructure Field-Effect Transistors" (2022). All Theses. 3870.
https://open.clemson.edu/all_theses/3870
Included in
Electrical and Electronics Commons, Electronic Devices and Semiconductor Manufacturing Commons, Semiconductor and Optical Materials Commons