Improving the output power of GaN-based light-emitting diode using Ag particles embedded within a SiO_2 current blocking layer

摘要

GaN-based light-emitting diodes (LEDs) fabricated with Ag particles embedded within a SiO_2 current blocking layer (CBL) are demonstrated. The Ag particles varied from 100 to 250 nm in size, and had a density of ～3.8 × 10~8cm~(-2). The transmittances obtained from CaN/sapphire and Ag particles/GaN/sapphire were 75 and 66% at 450 nm, respectively. The LEDs (chip size: 1000 × 1000 μm~2) fabricated with ITO-only, ITO/SiO_2 CBL, and ITO/Ag particles/SiO_2 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/SiO_2 CBL yielded 11.9 and 7.0% higher light output powers (at 20 mA) than the LEDs with the ITO-only and ITO/SiO_2 CBL, respectively. The improved output power is explained by the combined effects of the improved extraction and current spreading.