Improving the output power of GaN-based light-emitting diode using Ag particles embedded within a SiO2 current blocking layer. (July 2015)

• Record Type: Journal Article
• Authors: Park, Jae-Seong; Han, Jaecheon; Seong, Tae-Yeon
• Is Part Of: Superlattices and microstructures. Volume 83(2015)
• Page Start: 361
• Page End: 366
• Publication Date: 2015-07
• Subjects: Ag particle -- LED -- Extraction -- Current spreading; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2015.03.027
• Languages: English
• ISSNs: 0749-6036

Abstract

Highlights: 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. Abstract: 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 × 10 8 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 μm 2 ) 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.