Tailoring Effect of Enhanced Local Electric Field From Metal Nanoparticles on Electroluminescence of Silicon-Rich Silicon Nitride

The electroluminescence (EL) wavelength tailoring of silicon-rich silicon nitride (SiN_x)-based light-emitting devices (LEDs) is achieved by the modulation of the dimensions of Ag nanoparticles. Two EL peaks are observed in our SiN_x-based LEDs, both of which are red shifted with the increasing sizes of Ag nanoparticles. A reasonable explanation on this shift is proposed from the calculation of the local electric field surrounding Ag nanoparticles based on a simple model. This red shift of the two EL peaks as well as the evolution of their relative intensities is mainly originated from its weakening electric field enhancement with the increase of the size of Ag nanoparticles. Our work provides an alternative approach toward the fabrication of SiN_x-based LEDs with tunable EL wavelengths.