Improved device performance of AlGaInP-based vertical light-emitting diodes with low-n ATO antireflective coating layer

• Published in: Microelectronic engineering 2013-04, Vol.104, p.29-32
• Main Authors: Lee, Hee Kwan, Kim, Myung Sub, Yu, Jae Su
• Format: Article
• Language: English
• Subjects: AlGaInP/GaInP MQWs; Applied sciences; ATO antireflective coating layer; Coating; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Devices; Electric power generation; Electronics; Exact sciences and technology; Extraction; Fractures; Light extraction; Light-emitting diodes; Materials science; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Methods of deposition of films and coatings; film growth and epitaxy; Nanostructure; Oblique-angle deposition; Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Optoelectronic devices; Physics; Red vertical light-emitting diodes; Reduction; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Wavelengths
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2012.11.001

[Display omitted] ► We fabricated the AlGaInP-based VLEDs with low-n ATO antireflective coating layer. ► The low-n ATO films were deposited on the p-GaP window layer of LEDs by an oblique-angle sputtering method. ► The internal reflection was efficiently suppressed by coating the low-n ATO layer. ► The results showed the improved device performances of LEDs. We reported the effect of low-n Sb-doped tin oxide (ATO) antireflective (AR) coating layer on the device performance of AlGaInP-based red vertical light-emitting diodes (VLEDs). The ATO films with a quarter wavelength thickness of ∼90nm were deposited on the p-GaP window layer by an oblique-angle sputtering method. The ATO films with inclined nanocolumnar structures indicated a low refractive index of ∼1.8 at emitting wavelengths of AlGaInP-based VLEDs. For VLED with low-n ATO AR coating layer, the light output power was increased by 26% at 350mA with no deterioration of the electrical property compared to the conventional LED. Also, the enhanced light extraction led to the reduction in the electroluminescence peak wavelength shift at higher injection currents.