Micro-LED Chip Structure for Crack-Free Lift-Off and Alignment

The patent applies local quality by creating a protrusion only at specific locations (corners or edges) of the nitride semiconductor structure rather than uniformly across the entire structure. This localized protrusion reduces contact area at critical stress points where cracks initiate during laser lift-off, improving external quantum efficiency without requiring a uniform reduction that would waste space. The protrusion is strategically positioned to provide maximum crack prevention with minimum space consumption.

The patent extracts the protective function from a separate added structure and integrates it directly into the nitride semiconductor structure itself through the protrusion formation. Instead of adding a distinct protective layer or coating that would increase device complexity, the protective feature is created by modifying the existing semiconductor structure through selective etching or growth processes, making the protection inherent to the device architecture.

The patent applies multi-functionality by making the protrusion serve dual purposes: it acts as both a mechanical stop to prevent over-etching during laser lift-off (protecting the semiconductor structure) and as an alignment feature during chip bonding (ensuring precise positioning). This single structural element performs multiple critical functions, eliminating the need for separate alignment marks or positioning structures that would increase device complexity.