Further reduction of efficiency droop effect by adding a lower-index dielectric interlayer in a surface plasmon coupled blue light-emitting diode with surface metal nanoparticles
Journal
Applied Physics Letters
Journal Volume
105
Journal Issue
10
Date Issued
2014
Author(s)
Lin, C.-H.
Su, C.-Y.
Kuo, Y.
Chen, C.-H.
Yao, Y.-F.
Shih, P.-Y.
Chen, H.-S.
Hsieh, C.
Kiang, Y.-W.
Abstract
Further reduction of the efficiency droop effect and further enhancements of internal quantum efficiency (IQE) and output intensity of a surface plasmon coupled, blue-emitting light-emitting diode (LED) by inserting a dielectric interlayer (DI) of a lower refractive index between p-GaN and surface Ag nanoparticles are demonstrated. The insertion of a DI leads to a blue shift of the localized surface plasmon (LSP) resonance spectrum and increases the LSP coupling strength at the quantum well emitting wavelength in the blue range. With SiO2as the DI, a thinner DI leads to a stronger LSP coupling effect, when compared with the case of a thicker DI. By using GaZnO, which is a dielectric in the optical range and a good conductor under direct-current operation, as the DI, the LSP coupling results in the highest IQE, highest LED output intensity, and weakest droop effect.
SDGs
Type
journal article