MicroLED displays are among the most promising technologies for very small and large displays soon. The market adoption strongly depends on costs of the display. Shrinking MicroLED sizes with additional throughput and yield improvements are the key to a wider spread usage of the technology. Laser Lift-Off, a release of III-V based MicroLED´s from the growth wafer, and laser-based mass transfer are two mandatory process steps within the MicroLED display process chain. A UV laser masked based high precision imaging system will be presented which is capable to process GaN based MicroLED´s down to a few microns. The flexible maskbased system can process single die´s, large fields, and selective patterns of LED dies. Process results are depending on the precision and alignment of the dedicated laser beam. The influence of beam-to-die alignment, energy densities, material combination, and contact versus non-contact transfer will be shown and discussed. Both LLO and transfer can be scaled to large field sizes to enable a high throughput processing that pushes the technology into reasonable production time scales. Beam shapes, process speed assumptions, and capable substrate sizes will be discussed. Finally, a flexible system concept will be presented that can cover both LLO and selective mass transfer with corresponding different energy densities. This system concept has a capability to process MicroLED displays for AR/VR but also larger formats e.g. tiles which can be combined to large MicroLED TV´s or commercial signage applications.
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