In this manuscript, blue light emitting diodes (LEDs) with comb-shaped mesa and interdigital electrodes structure based on gallium nitride (GaN) are presented. This kind of LEDs have showed higher light output power and more efficient current spreading, comparing with a reference large-area LED. For the optimized LED structure, the light output power and external quantum efficiency, considering the actual emission area, reach to 600 mW and 73% at a forward current of 350 mA. The experimental results are consistent with the predictions of current expansion equations. The comb-shaped mesa structure decreases the total internal reflection (TIR) and the interdigital electrodes improve the current crowding effect, as validated from the electrical and optical tests. Therefore, the efficiency and reliability of the LED devices have been significantly enhanced by reducing the transverse current path. This work should be of guiding significance for structural design of large-area/high-power optoelectronic devices.

Compared with conventional light-emitting diode (LED), micro-LED has excellent photo-electric properties such as high current density, light output power density, light response frequency. It has widespread application prospects in the field of light display, optical tweezers, and visible light communication. However, dry etching inevitably leads the sidewall to be damaged, which results in the degradation of device properties. In this letter, a micro-LED array device based on F ions implantation isolation technology is presented to avoid damaging the sidewall. We systemically investigate the influence of fluorine ion implantation energy and light-emitting apertures on the photoelectric properties of the micro-LED array device by testing the current-voltage characteristic and light output power. The investigation results show that comparing with F ion 50 keV single implantation device, the reverse leakage of 50/100 keV double implantation device decreases by 8.4 times and the optical output density increases by 1.3 times. When the light-emitting apertures are different (6, 8, 10 μm respectively), the reverse leakage current remains constant, and the forward operating voltage decreasesfrom 3.3 V to 3.1 V and to 2.9 V with the increase of the aperture. Besides, the available area ratio, i.e. the ratio of actual light-emitting area to device area of single micro-LED with different light-emitting apertures are 85%, 87%, and 92%, respectively. The electrical isolation of the micro-LED array is realized by ion implantation isolation technology, and the micro-LED has some advantages over the conventional mesa etching micro-LED device, such as low reverse leakage current density, high optical output power density, and high effective light-emitting area ratio.