Improving the output power of GaN-based light-emitting diode using Ag particles embedded within a SiO2 current blocking layer

• Ag-particles are embedded within a SiO2 current blocking layer to enhance light output.
• Ag particles (100–250 nm in size) reduce the transmittance by causing photon scattering.
• LEDs fabricated with Ag particles show a 7.0% higher output power than that with SiO2 CBL.
• Improved output power is explained by the improved extraction and current spreading.

GaN-based light-emitting diodes (LEDs) fabricated with Ag particles embedded within a SiO2 current blocking layer (CBL) are demonstrated. The Ag particles varied from 100 to 250 nm in size, and had a density of ∼3.8 × 108 cm−2. The transmittances obtained from GaN/sapphire and Ag particles/GaN/sapphire were 75 and 66% at 450 nm, respectively. The LEDs (chip size: 1000 × 1000 μm2) fabricated with ITO-only, ITO/SiO2 CBL, and ITO/Ag particles/SiO2 CBL showed forward-bias voltages of 3.05, 3.25 and 3.1 V at 20 mA, respectively. The LEDs with the ITO/Ag particles/SiO2 CBL yielded 11.9 and 7.0% higher light output powers (at 20 mA) than the LEDs with the ITO-only and ITO/SiO2 CBL, respectively. The improved output power is explained by the combined effects of the improved extraction and current spreading.