Metallic Slurry Planarization of Light Conversion Layers in Displays

The patent changes the key parameter of the polishing slurry from conventional non-metallic abrasives to metallic slurry containing alumina or zirconia particles. This parameter change enables effective planarization with reduced damage because the metallic particles provide controlled abrasion that removes material uniformly without causing excessive mechanical stress or peeling of the bank structures.

The patent uses a composite polishing slurry system combining metallic particles (alumina or zirconia) with a liquid carrier. This composite material approach allows the polishing process to achieve both surface flatness and minimal damage by combining the abrasive properties of metal particles with the lubricating and cooling properties of the liquid medium, preventing thermal damage and reducing friction-induced peeling.

The patent applies preliminary planarization of the light conversion layer surface through chemical mechanical polishing before depositing the filler layer. This preliminary action creates a flat surface that reduces or eliminates the need for thick filler layers, thereby maintaining light emission efficiency while achieving the required surface flatness for subsequent processing steps.

The patent replaces the mechanical approach of using thick filler layers to compensate for surface irregularities with a chemical mechanical polishing process. This substitution allows for precise surface planarization that maintains the original surface topology without adding excessive material, thus preserving light emission efficiency while achieving the required flatness.

The patent changes the particle size parameter of the metallic slurry to an optimized range that balances polishing speed and bank adhesion. The specific particle size distribution enables effective removal of height differences between banks and light conversion patterns while controlling the mechanical stress to prevent peeling, achieving both productivity and strength requirements.

The patent uses the liquid carrier in the metallic slurry as an intermediary that mediates between the abrasive particles and the substrate. This intermediary provides lubrication and cooling during the polishing process, reducing friction and thermal stress that would otherwise cause bank peeling, while still allowing the abrasive particles to effectively remove material at a productive rate.