Tunable, Full-Color Nanowire Light Emitting Diode Arrays Monolithically Integrated on Si and Sapphire

The monolithic integration of red, green and blue (RGB) GaN-based light-emitting diodes (LEDs) directly on a single chip is critically important for smart lighting and full color display applications. In this work, RGB InGaN/GaN dot-in-a-wire LED arrays were laterally arranged on a Si wafer using a three-step SiOx-mask selective area growth (SAG) technique, and on a sapphire wafer using a Ti-mask SAG technique. Tunable emission across the entire visible spectral range (similar to 450 nm to 700 nm) can be readily achieved on a single Si wafer by varying the sizes and/or compositions of the dots. By separately biasing lateral-arranged multi-color LED subpixels, the correlated color temperature (CCT) values of such a similar to 0.016 mm(2) pixel can be varied from similar to 1900 K to 6800 K. The RGB pixel size can be further reduced by using the Ti-mask SAG technique on sapphire wafer. Full-color InGaN/GaN nanowire arrays with sizes of 2.8 x 2.8 mu m(2) have been monolithically fabricated into the same pixel.