Multi-Junction LED Structure with Common P-Type Electrode

The patent combines multiple light emitting structures into a single integrated LED device with a common substrate. Multiple n-type semiconductor layers, light emitting layers, and p-type semiconductor layers are formed on the same substrate, allowing parallel connection of multiple light emitting junctions. This merging approach achieves high brightness through combined light output while eliminating the need for individual examination and series connection of separate LED chips, thus reducing fabrication complexity

The common substrate serves multiple functions simultaneously: it supports multiple light emitting structures, provides mechanical strength, and acts as a common electrode connection point. The single substrate structure enables multiple light emitting junctions to function together as one integrated device, achieving both high brightness and simplified fabrication without requiring separate processing for each LED chip

Different light emitting layers are formed with specific local properties to generate different colors. Each light emitting layer contains quantum wells with tailored composition and thickness to emit at specific wavelengths. The n-type and p-type semiconductor layers are also locally optimized with different doping concentrations and compositions. This local quality differentiation enables multi-color emission while maintaining manufacturability through standardized fabrication processes

The patent employs composite semiconductor structures combining different materials (e.g., GaN, AlGaN, InGaN) with varying band gaps to create multiple light emitting layers. Each material composition is selected to produce specific colors, and the layered composite structure allows simultaneous emission of multiple colors. The composite material approach enables color versatility while using established semiconductor fabrication techniques