Stacked LED Pixel Architecture for Wafer-Level Display Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Micro-LED displays face challenges in mounting a large number of small micro-LEDs on a display panel due to their tiny size, which complicates the manufacturing process and increases complexity.
Innovation Solution
A light emitting diode pixel with a stacked structure is manufactured at the wafer level through wafer bonding, allowing multiple subpixels to share LED sub-units and reduce the number of individual LEDs needed, simplifying the mounting process and improving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If micro-LEDs are arranged on a two-dimensional plane with each subpixel having separate micro-LEDs, then color display capability is achieved, but the number of micro-LEDs required increases significantly and mounting complexity increases
Solution Approach 1:
Multiple subpixels share common LED sub-units (specifically, the blue LED sub-unit is shared among multiple subpixels). This merging approach reduces the total number of individual LEDs required while maintaining the ability to display multiple colors through selective activation and optical filtering.
Solution Approach 2:
The shared blue LED sub-unit serves multiple functions by providing the blue component for multiple different subpixels. This universal element is combined with different optical filters (color filters or quantum dot layers) to generate different colors for different subpixels, reducing redundancy.
2Reliability
If each subpixel has its own dedicated micro-LEDs, then color purity and independence are improved, but manufacturing complexity and mounting difficulty increase
Solution Approach 1:
The pixel structure is segmented into distinct functional layers: LED sub-units, optical filters/quantum dot layers, and electrode structures. This segmentation allows for modular manufacturing where each layer can be processed independently and then assembled, simplifying the overall manufacturing process while maintaining color purity through precise layer positioning.
Solution Approach 2:
The patent transitions from a planar two-dimensional arrangement of separate micro-LEDs to a three-dimensional stacked structure where LED sub-units are vertically arranged with optical filters and electrodes in between. This dimensional change enables sharing of LED sub-units across multiple subpixels while maintaining color purity through vertical optical path isolation.
3Adaptability or versatility
If a large number of micro-LEDs are mounted on the display panel, then full color display is achieved, but the mounting process becomes more complex and time-consuming
Solution Approach 1:
Multiple subpixels are merged to share common LED sub-units, specifically the blue LED sub-unit that is positioned to serve multiple subpixels. This merging reduces the total count of individual LEDs that need to be mounted on the display panel, directly improving mounting efficiency while maintaining full color display capability through the shared structure.
4Area of moving object
If micro-LEDs are made very small to fit more on the panel, then pixel density is improved, but mounting difficulty and precision requirements increase
Solution Approach 1:
The patent employs a three-dimensional stacked architecture where LED sub-units are arranged vertically rather than only horizontally. This vertical stacking allows for higher pixel density without proportionally increasing the difficulty of mounting, as the vertical layering can be achieved through wafer bonding and layer-by-layer assembly processes that are more tolerant to positioning variations than direct placement of extremely small components.
Solution Approach 2:
The pixel structure is divided into separable layers (LED sub-units, optical filters, quantum dot layers, electrodes) that can be manufactured and positioned independently. This segmentation allows each layer to be optimized for its specific function and assembled with appropriate precision requirements, rather than requiring all components to be mounted with extremely high precision simultaneously.
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 enables the simultaneous manufacturing of light emitting diode pixels, reducing the complexity of mounting micro-LEDs on a display panel and enhancing the manufacturing efficiency by sharing LED sub-units across subpixels.
Implementation Method 1
a first LED sub-unit configured to emit light
Implementation Method 2
manufactured at the wafer level through wafer bonding
Data Source
AI summary
A light emitting diode pixel for a display includes a first subpixel including a first LED sub-unit, a second subpixel including a second LED sub-unit, a third subpixel including a third LED sub-unit, and a bonding layer overlapping the first, second, and third subpixels, in which each of the first, second, and third LED sub-units includes a first type of semiconductor layer and a second type of semiconductor layer, each of the first, second, and third LED sub-units is disposed on a different plane, and light generated from the second subpixel is configured to be emitted to an outside of the light emitting diode pixel by passing through a lesser number of LED sub-units than light generated from the first subpixel and emitted to the outside.