Journal of the Optical Society of Korea

Optical Society of Korea (한국광학회)
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Enhanced Cathodoluminescence of KOH-treated InGaN/GaN LEDs with Deep Nano-Hole Arrays

  • Doan, Manh-Ha (Department of Electrical and Computer Engineering, Ajou University) ;
  • Lee, Jaejin (Department of Electrical and Computer Engineering, Ajou University)
  • Received : 2014.01.09
  • Accepted : 2014.05.07
  • Published : 2014.06.25
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Abstract

Square lattice nano-hole arrays with diameters and periodicities of 200 and 500 nm, respectively, are fabricated on InGaN/GaN blue light emitting diodes (LEDs) using electron-beam lithography and inductively coupled plasma reactive ion etching processes. Cathodoluminescence (CL) investigations show that light emission intensity from the LEDs with the nano-hole arrays is enhanced compared to that from the planar sample. The CL intensity enhancement factor decreases when the nano-holes penetrate into the multiple quantum wells (MQWs) due to the plasma-induced damage and the residues. Wet chemical treatment using KOH solution is found to be an effective method for light extraction from the nano-patterned LEDs, especially, when the nano-holes penetrate into the MQWs. About 4-fold CL intensity enhancement factor is achieved by the KOH treatments after the dry etching for the sample with a 250-nm deep nano-hole array.

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References

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