Remote epitaxial crystalline perovskites for ultrahigh-resolution micro-LED displays

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Miniaturization of light-emitting diodes (LEDs) is crucial for ultrahigh-resolution displays.
• Metal-halide perovskites offer potential for efficient light emission and scalable manufacturing of micro-LEDs.
• Existing thin-film perovskites face challenges with emission inhomogeneity, surface instability, and device integration.

Purpose of the Study:

• To develop continuous single-crystalline perovskite films for advanced micro-LED applications.
• To overcome challenges in perovskite film growth and integration into micro-LED devices.
• To achieve high-performance micro-LEDs with enhanced efficiency and brightness.

Main Methods:

• Remote-epitaxy growth of crystalline perovskite films using a subnanometre graphene interlayer.
• Facilitation of strain relaxation and transfer of perovskite films.
• Integration of free-standing perovskite films into micro-LEDs with pixel sizes down to 4μm.

Main Results:

• Achieved micro-LEDs with a pixel size down to 4μm.
• Demonstrated high electroluminescence efficiency (16.7%) and brightness (4.0 × 10⁵ cd/m⁻²).
• Attributed performance to suppressed defects and efficient carrier transport in highly crystalline, strain-relaxed epitaxial perovskites.

Conclusions:

• Remote epitaxy enables seamless integration of high-quality perovskite films into micro-LEDs.
• The developed micro-LEDs show significant potential for static and dynamic display applications.
• This work paves the way for on-chip perovskite photonic sources, including ultracompact lasers and ultrafast LEDs.