MicroLED transfer technologies for emerging optoelectronic applications

초록

Micro-light-emitting diodes (microLEDs) are emerging as a key enabling technology for next-generation optoelectronic systems, particularly in augmented reality (AR), virtual reality (VR), and ultra-high-resolution displays. Despite their advantages in brightness, efficiency, and lifetime, large-scale integration of microLEDs remains constrained by the lack of scalable and reliable transfer processes capable of assembling millions of microscopic devices with high yield and precise alignment. As device dimensions shrink below 50 μm and pixel densities increase, conventional serial pick-and-place techniques face fundamental limitations in throughput, yield, and alignment accuracy. This paper provides a concise overview of representative microLED transfer technologies, including fluidic self-assembly (FSA), elastomeric stamp-based transfer printing, laser-assisted lift-off, and electrostatic transfer approaches, and discusses their performance trade-offs based on experimentally reported metrics such as throughput, placement precision, scalability, and substrate compatibility. Particular attention is given to FSA-based transfer, which enables parallel, low-cost assembly of large numbers of microLED chips through hydrodynamic and surface-energy-driven assembly mechanisms. Recent studies demonstrate that FSA can achieve high-yield, fine-pitch microLED integration compatible with rigid, flexible, and curved substrates, including architectures relevant to AR/VR and wearable display platforms. Finally, remaining challenges and future directions for microLED transfer technologies are discussed, with emphasis on defect tolerance, process control, and hybrid assembly strategies for practical optoelectronic applications. © 2026 SPIE. All rights reserved.

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