Prednáška Dr. Chao Yuan
ElÚ SAV pozýva na prednášku, ktorú bude mať Dr. Chao Yuan, (The institute of technological sciences, Wuhan University, China) s názvom: Pump-probe thermoreflectance techniques for non-contact and non-invasively characterizing the thermal properties of wide bandgap semiconductors
Dňa 15.11.2022 o 10:00 hod., vo veľkej zasadačke ElÚ SAV (101).
Pump-probe thermoreflectances (pump-probe TR) have emerged as the powerful and versatile tools for the characterization of wide bandgap (WBG) and ultrawide bandgap (UWBG) semiconductor thermal transport properties. This lecture begins with the basic principles and standard implementations of pump-probe TR techniques, illustrating that when analysing WBG and UWBG materials or devices with pump-probe TR or TTI, a metal thin-film layer is often required. Due to the transparency of the semiconductor layers to light sources with sub-bandgap energies, these measurements directly on semiconductors with bandgaps larger than 3 eV remain challenging. This lecture then summarizes the general applications of pump-probe TR and TTI techniques for characterizing WBG and UWBG materials where thin metals are utilized, followed by introducing more advanced approaches to conventional pump-probe TR methods, which achieve the direct characterizations of thermal properties on GaN-based materials without the use of thin-film metals. Discussions of these techniques show that they provide more accurate results and rapid feedback and would ideally be used as a monitoring tool during manufacturing. Finally, this lecture concludes with a summary that discusses the current limitations and proposes some directions for future development.