Electroluminescence comparison of photonic crystal light-emitting diodes with random and periodic hole structure

Abstract

We compare the characteristics of photonic crystal (PC) light-emitting diodes (LEDs) with the same hole pattern density of 12 ea mu m(-2). The PC LED with periodic hole structure demonstrated an increased output power, improved external efficiency at high current operation and uniform radiation owing to the periodic nanoscale features generating a photonic band gap (PBG), when compared with those of the random hole (RH) LED. The electroluminescence images obtained by confocal scanning electroluminescence microscopy (CSEM) show the difference of light emission propagation from the random and periodic structures.