Electrically Driven Sub-Micrometer Light-Emitting Diode Arrays Using Maskless and Etching-Free Pixelation

Abstract

For decades, group-III-nitride-based light-emitting diodes (LEDs) have been regarded as a light emitting source for future displays by virtue of their novel properties such as high efficiency, brightness, and stability. Nevertheless, realization of high pixel density displays is still challenging due to limitations of pixelation methods. Here, a maskless and etching-free micro-LED (mu LED) pixelation method is developed via tailored He focused ion beam (FIB) irradiation technique, and electrically driven sub-micrometer-scale mu LED pixel arrays are demonstrated. It is confirmed that optical quenching and electrical isolation effects are simultaneously induced at a certain ion dose (approximate to 10(14) ions cm(-2)) without surface damage. Furthermore, highly efficient mu LED pixel arrays at sub-micrometer scale (square pixel, 0.5 mu m side length) are fabricated. Their pixelation and brightness are verified by various optical measurements such as cathodo-, photo-, and electroluminescence. It is expected that the FIB-induced optical quenching and electrical isolation method can pioneer a new defect engineering technology not only for mu LED fabrication, but also for sub-micrometer-scale optoelectronic devices.