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Improvement of Brightness for AlGaInP High-brightness LEDs with Nano-scale Roughness on Top-GaP Surface

Top-GaP 상부에 나노 크기의 Roughness 처리에 의한 AlGaInP 고휘도 LED의 휘도 향상

  • Published : 2008.01.01

Abstract

AlGaInP high-brightness LEDs(HB-LEDs) have gained importance a variety of application operating in the red, orange, yellow and yellow-green wavelength. The light generated from inside LED chips should be emitted to the air through the surfaces of the chips. However, because of the differences between the semiconductor and air or epoxy's refractive index, some of the light was blocked so that caused lowering external quantum efficiency. In this study, nano-scale roughness on the top-GaP layer of AlGaInP epitaxial wafer was fabricated to improve' the brightness of AlGaInP LEDs. Nano-scale roughness was made by ICP dry etcher. Our AlGaInP LEDs with nano-scale roughness has higher brightness (about 28.5 %) than standard AlGaInP LEDs.

Keywords

AlGalnP;LED(Light-emitting diode);Surface roughness;ICP(Inductively coupled plasma);Dry etching

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