Wafer-Scale Monolithic Integration of LEDs with p-GaN-Depletion MOSFETs on a GaN LED Epitaxial Layer

We developed a monolithically integrated device consisting of a single GaN LED and two p-GaN-depletion MOSFETs on a GaN LED epitaxial layer. The p-GaN-depletion MOSFETs exhibited a subthreshold slope of 1 V/decade and a threshold voltage of –2 V, whereas the LED exhibited a forward voltage of 3.5 V at 1 mA and an electroluminescence peak of 445 nm. The device could be controlled by the scan voltage, with $V_{DD}$ ranging from 1 to 2 V, and cut off the total current with an applied scan voltage greater than 3 V. This work represents an important step towards the monolithic integration of LED and transistors for use in active-matrix micro-LED displays.