Micro-LED Color Conversion Layers With Self-Aligned UV Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for fabricating micro-LED displays face challenges in accurately and cost-effectively integrating color conversion agents for different colors onto micro-LEDs, particularly due to issues with alignment accuracy, scalability, and throughput using shadow masks, inkjet, and aerosol jet techniques.
Innovation Solution
A method involving self-aligned in-situ curing of photocurable compositions containing blue photoluminescent materials and nanomaterials, which are selectively deposited and polymerized using UV light to form color conversion layers, enabling precise and efficient conversion of ultraviolet or blue light to red or green light for micro-LEDs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If shadow masks are used for selective deposition of color conversion agents, then color conversion layers can be formed on micro-LEDs, but alignment accuracy and scalability deteriorate
Solution Approach 1:
The patent removes the shadow mask component entirely from the system. Instead of using a physical mask to define patterns, the invention uses direct inkjet printing to deposit color conversion materials only where needed on the micro-LED array, eliminating alignment errors associated with mask positioning while maintaining scalability.
Solution Approach 2:
The patent replaces the mechanical shadow mask system with a digital printing system. The pattern definition transitions from physical mask geometry to digital print head control, allowing precise material placement without mechanical alignment constraints and enabling easier scaling to larger substrates.
2Manufacturing precision
If inkjet techniques are used for selective deposition of color conversion agents, then deposition precision is improved, but resolution and throughput deteriorate
Solution Approach 1:
The patent employs a multi-functional inkjet printing system that can handle multiple material types (different color conversion materials, encapsulants, and adhesives) with a single device. This universal platform achieves both high deposition precision through digital control and high throughput through parallel printing capabilities and optimized material formulations that cure rapidly.
3Area of stationary object
If aerosol jet techniques are used for selective deposition of color conversion agents, then coverage is improved, but throughput deteriorates
Solution Approach 1:
The patent implements continuous inkjet printing processes where material is deposited in a continuous stream that is digitally modulated to form droplets only at desired locations. The print head moves continuously over the substrate without stopping or repositioning, maintaining continuous productive action while achieving complete coverage through overlapping scan paths and optimized deposition rates.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach results in high photoluminescence quantum yield, long lifetime, and long shelf lifetime for the blue color converters, improving the manufacturing efficiency and accuracy of micro-LED displays.
Implementation Method 1
The blue photoluminescent material is selected to emit blue light in response to absorption of the radiation in the first wavelength band from each of the light-emitting diodes
Implementation Method 2
The nanomaterial is selected to emit red or green light in response to absorption of the radiation in the second wavelength band from each of the light-emitting diodes
Implementation Method 3
A first photo-curable fluid includes a blue photoluminescent material selected to absorb ultraviolet light, one or more first monomers, and a first photoinitiator that initiates polymerization of the one or more first monomers in response to absorption of the ultraviolet light
Data Source
AI summary
A light-emitting device includes a plurality of light-emitting diodes, a first cured composition over a first subset of the light-emitting diodes, and a second cured composition over a second subset of light-emitting diodes. The first cured composition includes a first photopolymer and a blue photoluminescent material that is an organic, organometallic, or polymeric material, embedded in the first photopolymer. The second cured composition includes a second photopolymer and a nanomaterial embedded in the second photopolymer. The nanomaterial is selected to emit red or green light in response.