Micro LED Manufacturing via Monocrystalline Seed Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing image display devices using micro LEDs are time-consuming and prone to connection defects, leading to reduced yield and high costs, especially for high-definition displays like 4K and 8K, due to the complexity of individually transferring and connecting numerous micro LEDs to a substrate with a drive circuit.
Innovation Solution
A method involving the formation of a substrate with a conductive layer, a semiconductor layer, and a light-emitting element, where a via extends through insulating films to electrically connect the light-emitting element to a circuit, reducing the transfer process time and increasing yield by forming the light-emitting elements directly on the substrate before transfer, utilizing monocrystallized conductive layers and low-temperature sputtering for crystal growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If individually-formed micro LEDs are sequentially transferred to a drive circuit substrate, then connection between light-emitting elements and circuits is achieved, but the transfer process becomes extremely time-consuming and connection defects increase for high-definition displays
Solution Approach 1:
The invention segments the manufacturing process into two distinct stages: (1) batch formation of multiple light-emitting elements on a first substrate, and (2) dicing the first substrate to separate and transfer individual elements to the drive circuit substrate. This segmentation allows parallel processing of multiple elements simultaneously, dramatically improving productivity while maintaining connection quality through controlled transfer processes.
Solution Approach 2:
The invention performs preliminary actions by forming all light-emitting elements on the first substrate before any transfer operation. The elements are completely formed with their semiconductor layers, electrodes, and insulating films in place, allowing subsequent dicing and transfer to proceed efficiently without requiring individual element manipulation during formation, thus resolving the contradiction between speed and quality.
2Productivity
If individually-formed micro LEDs are sequentially transferred to a drive circuit substrate, then connection is achieved, but the number of connection defects increases and yield decreases
Solution Approach 1:
The invention applies beforehand cushioning by forming a protective insulating film covering the light-emitting elements before dicing the first substrate. This insulating film prevents damage to the elements during the dicing and transfer processes, reducing connection defects and improving yield while maintaining high manufacturing efficiency through batch processing.
Solution Approach 2:
The first substrate serves as an intermediary carrier that holds multiple light-emitting elements during formation and protects them during transfer. This intermediary structure allows batch processing and reduces handling of individual elements, thereby improving both productivity and yield by minimizing mechanical damage and connection defects.
3Manufacturing precision
If many micro LEDs are individually formed and transferred for high-definition displays, then image quality improves, but an enormous amount of time is necessary for the transfer process
Solution Approach 1:
The invention merges the formation process of multiple light-emitting elements into a single batch operation on the first substrate. Instead of forming and transferring elements individually, multiple elements are formed simultaneously using the same semiconductor layers and processing steps, then diced and transferred together, reducing total process time while maintaining high-definition image quality.
Solution Approach 2:
The invention performs preliminary formation of all light-emitting elements on the first substrate before any transfer operation. This preliminary batch formation includes creating semiconductor layers, light-emitting layers, electrodes, and insulating films for all elements simultaneously, dramatically reducing the total time required compared to sequential individual formation and transfer, while achieving high-definition display quality.
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 significantly reduces the manufacturing time for high-definition displays, increases yield by minimizing connection defects, and allows for the production of high-definition image display devices with improved luminous efficiency and reduced costs.
Implementation Method 1
a conductive layer that is located on the first insulating film and includes a single-crystal metal, a semiconductor layer that is located on the conductive layer
Implementation Method 2
utilizing monocrystallized conductive layers and low-temperature sputtering for crystal growth
Data Source
AI summary
A method for manufacturing an image display device includes: preparing a substrate comprising a circuit and a first insulating film covering the circuit; forming a conductive layer on the first insulating film, the conductive layer comprising a single-crystal metal; forming a semiconductor layer on the conductive layer, the semiconductor layer comprising a light-emitting layer; forming a light-emitting element including a bottom surface on the conductive layer, and a light-emitting surface at a side opposite to the bottom surface; forming a second insulating film covering the conductive layer, light-emitting element, and first insulating film; forming a first via extending through the first and second insulating films; and forming a wiring layer on the second insulating film. The first via is located between the wiring layer and the circuit and electrically connects the wiring layer and the circuit. The light-emitting element is electrically connected to the circuit via the wiring layer.