Significant Quantum Efficiency Enhancement of InGaN Red Micro-Light-Emitting Diodes with a Peak External Quantum Efficiency of up to 6%

We demonstrate a significant quantum efficiency enhancementofInGaN red micro-light-emitting diodes (mu LEDs). The peak externalquantum efficiency (EQE) of the packaged 80 x 80 mu m(2) InGaN red mu LEDs was largely increased to 6.0% at 12A/cm(2), representing the significant process in exploringthe efficiency of InGaN red mu LEDs. The improvement of the EQEis attributed to the significant enhancement of the quantum efficiency,which is confirmed by the electron-hole wavefunction overlapin the InGaN quantum well from the band gap simulation and the photoluminescenceintensity ratio at room temperature/low temperature. Ultrasmall 5x 5 mu m(2) InGaN red mu LEDs were also obtained,which show a high peak EQE of 4.5%. This work demonstrates a simpleapproach to achieving highly efficient InGaN red mu LEDs, whichare very promising candidates for ultrasmall red mu LEDs requiredby AR/VR displays.