Investigation of InGaN-based flexible RGB micro-light-emitting diodes and their monolithic integration

This study demonstrated InGaN-based flexible RGB micro-light-emitting diodes (μLEDs) with size ranging from 20 to 100 μm through laser liftoff and UV-tape-assisted transfer process. The fabrication process of flexible RGB μLEDs released the stress of GaN films, which reduced the bending of energy band and screened the quantum-confined Stark effect in InGaN quantum wells based on theoretical simulation. Thus, a clear blue shift of peak wavelength was observed especially for red μLEDs. The electrical and electroluminescent performance, such as forward voltage, peak wavelength, and full width half maximum of flexible RGB μLEDs, could remain approximately identical under different bending radii from 3 to 7 mm. We realized the monolithic integration of flexible RGB μLEDs and obtained a wide color gamut that covered around 78% of the Rec. 2020 at bending conditions.