Multicolor LED Pixel Structure Without Pick-and-Place Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optoelectronic devices face challenges in manufacturing pixels that directly emit multiple colors without resorting to costly and inefficient 'pick and place' techniques, and they suffer from high light losses due to the use of color converters.
Innovation Solution
The optoelectronic device comprises a plurality of pixels, each including primary, secondary, and tertiary sub-pixels with light-emitting diodes (LEDs) emitting different wavelengths. These LEDs have a semiconductor structure with a primary lattice parameter accommodation layer, allowing for epitaxial growth of active semiconductor portions that emit specific colors without the need for color converters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If 'pick and place' technique is used to manufacture multi-color pixels, then color accuracy is improved, but manufacturing cost increases and production time is extended
Solution Approach 1:
The patent merges multiple separate manufacturing processes into a single integrated epitaxial growth process. Different color LEDs are grown simultaneously on the same substrate in different regions, eliminating the need for separate fabrication and assembly steps for each color component.
Solution Approach 2:
The epitaxial reactor is designed to perform multiple functions: it can grow different semiconductor materials with different bandgaps (producing different colors) using the same equipment and process platform, making the manufacturing system universally capable of producing all color components.
2Device complexity
If color converters are used to achieve multiple colors from LEDs, then device complexity is reduced, but light extraction efficiency decreases due to high light losses
Solution Approach 1:
The invention extracts the color conversion function from the optical path by eliminating color converters entirely. Instead of converting light wavelengths through phosphor layers, the system directly emits different wavelengths from separately grown LED regions, removing the source of light losses.
Solution Approach 2:
The patent introduces an intermediary approach where spatial separation replaces wavelength conversion. Different color regions act as intermediaries that directly provide the desired wavelengths without requiring conversion, maintaining energy efficiency while achieving color diversity.
3Area of stationary object
If small-diameter LEDs are used to increase pixel density, then area utilization is improved, but manufacturing precision requirements increase and yield decreases
Solution Approach 1:
The patent performs preliminary action by growing all LED structures to their final dimensions directly in the epitaxial reactor before any device-level processing. This allows precise control of dimensions during the growth phase when materials are still in a controllable state, avoiding the need for subsequent miniaturization steps that would require ultra-precise lithography.
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 solution enables the direct emission of multiple colors from each pixel using a single manufacturing technique, reducing production costs and increasing light extraction efficiency, while avoiding the use of small-diameter LEDs and color converters.
Implementation Method 1
a second primary active semiconductor portion formed by epitaxial growth from the primary lattice parameter accommodation layer
Implementation Method 2
at least one primary light-emitting diode adapted to emit a first light radiation substantially having a first wavelength
Implementation Method 3
each light-emitting diode comprises an active material which may or may not exploit quantum wells
Data Source
AI summary
An optoelectronic device includes pixels that each have at least one primary sub-pixel having a primary light-emitting diode formed on a support face a substrate provided with a first primary semiconductive portion that has an overall elongated wire-like shape having a top end, a primary lattice parameter accommodation layer arranged on the top end of the first primary semiconductive portion, a second primary active semiconductive portion arranged at least on the primary lattice parameter accommodation layer, and a third primary semiconductive portion arranged on the second primary active semiconductive portion. The primary lattice parameter accommodation layer has, with the second primary active semiconductive portion, a first difference in primary lattice parameters between 2.12% and 0.93% relative to the second primary active semiconductive portion.