Monolithic Micro LED Pixel Transfer via Wafer Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for fabricating micro LED displays face challenges in power consumption, manufacturing cost, and defectivity, particularly in transferring multiple color micro LEDs, which result in high costs and low manufacturing throughput.
Innovation Solution
The approach involves manufacturing monolithic red, green, and blue pixels on a wafer and transferring them as a whole pixel using wafer-to-wafer bonding equipment, with techniques like thermo-compression bonding and fluidic self-assembly to align and bond micro LEDs to a display backplane, reducing the need for individual color transfers and enhancing manufacturing efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If individual color micro LEDs are transferred separately, then color accuracy is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The patent combines multiple color micro LEDs (red, green, blue) into a single integrated pixel structure on the carrier substrate. This merging approach allows all color elements to be transferred simultaneously in one operation, reducing manufacturing complexity while maintaining color accuracy through the integrated pixel design
2Productivity
If wafer-to-wafer bonding is used, then manufacturing throughput is improved, but alignment precision requirements increase
Solution Approach 1:
The patent prepares alignment features and bonding interfaces in advance on both the carrier substrate and display substrate before the bonding process. This preliminary preparation ensures that when wafer-to-wafer bonding occurs, the pre-established alignment features guide the positioning, achieving high alignment precision while maintaining fast throughput
3Ease of manufacture
If monolithic pixel transfer is used, then manufacturing cost is reduced, but transfer reliability decreases
Solution Approach 1:
The patent segments the monolithic pixel into distinct color elements (red, green, blue micro LEDs) that are individually positioned within the pixel structure. This segmentation allows for defect identification and isolation, improving transfer reliability while maintaining the cost benefits of monolithic fabrication
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 method achieves a two-fold reduction in power consumption compared to OLED displays, leading to extended battery life and improved manufacturing yield, while reducing manufacturing costs and defect density, thus enabling more efficient production of micro LED displays for portable electronics.
Implementation Method 1
a heating element for heating the adhesive layer
Implementation Method 2
a pressure element for applying pressure to bond the carrier plate to the display backplane substrate
Data Source
AI summary
Micro light-emitting diode (LED) displays and assembly apparatuses are described. In an example, a pixel element for a micro-light emitting diode (LED) display panel includes a first color nanowire LED, a second color nanowire LED, the second color different than the first color, and a pair of third color nanowire LEDs, the third color different than the first and second colors. A continuous insulating material layer ius laterally surrounding the first color nanowire LED, the second color nanowire LED, and the pair of third color nanowire LEDs.