Atomic layer deposition technology for the development of high-quality, full-colour micro-LED displays

Micro light-emitting diodes (μLEDs) with unparalleled photoelectric characteristics are essential components for developing metaverse-related technologies. Immersive displays require reducing the LED size to the micro- or sub-microscale while retaining optimal optoelectronic capabilities. μLEDs, fabricated through the quantum dots colour conversion layer (QDs-CCL) process, offer a cost-effective solution for achieving displays with full-colour and ultrahigh quality. However, the sidewall defects significantly affect the optical and electrical properties of μLEDs with reduced chip size. Furthermore, QDs suffer from low excitation radiation and inferior operational stability induced by their intrinsic properties. Atomic layer deposition (ALD) is a promising chemical surface treatment technique with self-limiting properties that can enhance full-colour μLED devices. In this review, we explore recent studies on ALD techniques for full-colour μLED device fabrication. We discuss in detail the significant contribution of ALD in repairing sidewall defects in RGB tricolour μLED chips. Moreover, we explore applications of ALD in the protection of QDs and preparation of high-resolution CCLs. Finally, we discuss future prospects of ALD in developing high-resolution, full-colour displays.