Comparison on the electroluminescence of Si-rich SiNx and SiOx based light-emitting diodes

Abstract

Electroluminescence (EL) of the metal-insulator-semiconductor light-emitting diodes (MISLEDs) made by Si-rich SiNx and SiOx films with buried Si nanocrystals are compared. The SiNx facilitates carrier transport and EL from MISLED with turn-on current and voltage of 4 μA and 12 V by reducing barrier heights at indium tin oxide /SiNx and SiNx/Si-nc interfaces. The SiNx MISLED exhibits larger charge loss rate of 12% within 200 s and shorter delay time of 3.86×10−4 sec than SiOx one, which limit its external EL quantum efficiency by strong carrier escaping effect due to the insufficient carrier confinement in Si nanocrystals with low interfacial barriers.