Hybrid CMOS Micro-LED Layout for Uniform Four-Side Current Injection

The power plane is segmented into multiple functional zones including cathode contact areas, Vled contact areas, and redistribution rings distributed across the substrate. This segmentation allows current to be distributed through multiple pathways rather than concentrated in single layers, achieving uniform current distribution while maintaining a minimal number of metal layers.

The patent transitions from vertical stacking of multiple metal layers to a planar two-dimensional distribution network. By arranging cathode contacts, Vled contacts, and redistribution rings in alternating patterns across the substrate plane, the design achieves three-dimensional current distribution effects using primarily two-dimensional routing, reducing the need for additional metal layers.

Different regions of the power plane are designed with locally optimized properties. Cathode contact areas feature higher density interconnects for current collection, while Vled contact areas and redistribution rings are spaced to provide current distribution. This local quality variation allows high current density where needed for brightness while distributing heat and current stress to protect against electromigration in critical interconnect regions.

Redistribution rings serve as intermediary structures between cathode contacts and Vled contacts. These rings collect current from cathode contacts and redistribute it to multiple Vled contacts, acting as current mediators that prevent excessive current concentration at single points. This intermediary function reduces peak current density and associated heat generation while maintaining the ability to drive pixels at required brightness levels.