All-GaN monolithic integration of 2T1C pixel circuits with μLEDs

We demonstrate the first, to the best of our knowledge, all-GaN monolithic integration of two-transistor-one-capacitor pixel circuits with micro-light-emitting diodes (2T1C-μLEDs). A self-aligned selective area regrowth technique was developed to epitaxially integrate μLEDs on GaN-based high-electron-mobility transistors (HEMTs), yielding excellent structural homogeneity and optical performance of the monolithically integrated μLED pixels. The light intensity of the monolithically integrated 2T1C-μLEDs can be effectively modulated by the data signal (V_data), scan signal (V_scan), and supply voltage (V_DD) applied to the integrated 2T1C pixel circuits. The all-GaN monolithic integration strategy eliminates complex transfer and bonding processes in conventional hybrid integration, unlocking the potential of high-performance and cost-effective μLED displays.