IEEE Electron Device Letters · 2012 · 21 citations · 7 references
EngineeringElectrical EngineeringMaterials ScienceElectronic MaterialsOptoelectronicsSemiconductor DevicesLight SourcesLight-emitting DiodesLuminescent MaterialsOptical SourcesOptoelectronic DevicesPhotonic Integrated CircuitsEtch Mask DesignEtch Mask FabricationEtch Mask MaterialsGallium Nitride Light-emitting DiodesOptical Path LengthPhoton Path LengthPower OutputVertical Light-emitting Diodes
We demonstrated the fabrication and study of vertical-stand-type homoepitaxial light-emitting diodes (VLEDs) on a GaN substrate with conical array structures. The conical arrays were formed on the N-face surface of the GaN substrate using a size-controllable polystyrene nanosphere as etch mask. The 20-mA output power of the VLEDs with flat backside, truncated cone, and cone arrays improved by magnitudes of 16.5%, 66.8%, and 118.5%, respectively, compared with that of conventional planar configuration LEDs. These improvements could be attributed to the increased direct illumination surface and reduction in photon extraction path length. Moreover, small wavelength redshift proved that the VLED on the GaN substrate did not suffer from serious thermal effect.
7
Air-voids embedded high efficiency InGaN-light emitting diode
Eun-Hyun Park, Jin Jang, Shalini Gupta et al. · Applied Physics Letters · 2008 · 76 citations