Evidence of electron induced interfacial defects in electron-gun-deposited insulator InP structures

Abstract
Using the photoluminescence and capacitance-voltage measurements, it has been shown that low-energy electron beam evaporation of Al2O3 on n-type InP induces defects in the interfacial region of the InP-Al2O3 structure. These defects seem to be located as fixed charge traps in the insulator as well as confined within a few hundreds of angstroms of the InP in the interfacial region. By introducing a metallic grid in the path of the evaporating dielectic flux, the substrate was effectively protected from the electron bombardment which resulted in a major improvement of the final metal-insulator-semiconductor device characteristics.