Next generation light emitting device for microLED Display: ZOGAN LED

We have developed a new light emitting device named ZOGAN LED. It is composed with the p-layer comprising p-ZnO and p-GaN. ZOGAN LED and GaN LED are dramatically different in device performance. For example, it is well known for GaN LED that the EQE of GaN LED becomes worse, as either the device size is getting smaller, or the injection current is larger. However, unlike GaN LED, ZOGAN LED shows no EQE droop with current increase or size decrease, while keeping its EQE level exceptionally high. No EQE droop and no size-dependent EQE decrease are unique features of ZOGAN LED, which is never ever reported before. The non-radiative leakage current is almost negligible and not increased as the chip size decreases even below 10um for ZOGAN microLED. For these unique properties, ZOGAN microLED is critical to accomplish the high-efficient microLED displays with >5,000PPI resolution. In this presentation, we will report the features of ZOGAN microLED, based on experimental results of electrical/optical measurements. After brief discussion and review on physical properties of ZOGAN LEDs, ZOGAN microLEDs in different chip sizes (20, 10, and 5 microns in diameter) will be demonstrated.