Band offsets at the interfaces of InxGa1-xAs / Al2O3 / Al where x = 0.53 and x = 0.75 were determined by internal photoemission and spectroscopic ellipsometry. The photoemission energy threshold at the InxGa1-xAs / Al2O3 interface was found to be insensitive to the Indium composition, but shifted to a lower energy after a post-deposition annealed at high temperatures. Sub-threshold electron photoemission was also observed for the annealed sample attributing to interfacial layer formation during the annealing process.
Citation: Applied Physics Letters
Pub Type: Journals
Al2O3, InGaAs, ALD, internal photoemission, ellipsometry, MOS, band offset, band alignment