The monolithic integration of InGaN-based multi-color light-emitting diodes (LEDs) exerts a great impact on the full-color application field. The two dimensional arrangement of three primary colors micro-LED is expected to be used as a semiconductor video panel . The emission color of InGaN/GaN triangular latticed nanocolumn arrays with the same lattice constant (L) is controlled by the nanocolumn diameter (D) . For a blue light emission, the narrow nanocolumns should be utilized, resulting in a low filling factor of nanocolumns. However, the use of high filling factor of nanocolumn system is suitable for a stable device fabrication. In this study, therefore, we fabricated the densely-packed regularly arranged InGaN nanocolumns (D/L > 0.9). For the nanocolumn arrays with high filling factors, it was found that the emission color shifted from blue to red with increasing L from 80 to 350 nm. The emission color change is attributed to the different mechanism from Ref. , which is investigated to be clarified. Using the emission color change for the high filling factor nanocolumn system, four-color (red, green, blue, and yellow; RGBY) micro light emitting diodes (LEDs) were integrated in a 20×20 μm2 area (hereinafter called “unit”) and the units were two-dimensionally arrayed in a 16×16 square lattice in 400×400 mm2 area. These nanocolumn micro-LEDs were independently driven using matrix wiring electrodes, exhibiting RGBY light emissions.
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