Monolithic Integration Process of Driving Switch for GaN Micro LED

This study demonstrates the integration of an AlGaN/GaN heterojunction field-effect transistor (HFET) with a built-in micro-light emitting diode (LED), referred to as a driving switch-integrated micro-LED. AlGaN/GaN HFETs are known for their excellent electron mobility and high current density, making them suitable for high-speed and high-power switching applications. By incorporating a p-GaN/AlGaN/GaN heterojunction-based LED structure in the drain region of a p-GaN/AlGaN/GaN HFET, we achieved monolithic integration that allows the HFET switching transistor to control the integrated micro-LED operation. The threshold voltage of the enhancement-mode switching p-GaN/AlGaN/GaN HFET was 1.7V, and the turn-on voltage of the monolithically integrated micro-LED was 4V. This approach represents a significant advancement in monolithic switching for GaN-based devices and confirms the potential for developing optoelectronic integrated devices using a simple and cost-effective process.