Enhanced Performance of GaN-Based Single Contact Micro-LED Driven by AC Power Utilizing the Tunnel Junction

The alternating current (ac)-driven GaN-based single contact light-emitting diode (SC-LED) has garnered significant attention due to its unique driving technique and potential applications, especially in areas where direct current-driven (dc-driven) LEDs face limitations. Our previous research emphasizes the importance of reducing the operating voltage of SC-LED. In this study, we have developed and manufactured a novel SC-LED featuring a tunnel junction (TJ) structure, which exhibits a lower breakdown voltage ( ${V} _{\text {breakdown}}$ ) compared to conventional LEDs with an ITO contact layer. The simulation and experimental data illustrate a significant performance gap between TJ SC-LED and ITO SC-LED. The working voltage of TJ SC-LED is 34 V, which is 29% lower than that of ITO SC-LED. Specifically, under ac power at 80 V, TJ SC-LED exhibits a current of 0.94 mA and a WPE of 3.22%, both higher than the 0.77 mA and 3.02% values recorded for the ITO SC-LED. This comparison underscores the superior performance of TJ SC-LED over ITO SC-LED. These findings enhance our understanding of SC-LEDs and pave the way for the advancement of new driving techniques in nano-sized displays.