Micro-Vacuum Module for Selective Micro-LED Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for transferring micro-light-emitting diodes (micro-LEDs) are inefficient and costly, particularly for large-area displays, due to limitations in transfer yield, device failure risks, and the inability to repeatedly use transfer members, which hinders the application of micro-LEDs in the display industry.
Innovation Solution
A method utilizing a micro-vacuum module with adsorption holes and vacuum flow channels to selectively detach and transfer micro-LED arrays of red, green, and blue colors from a mother or temporary substrate to a target substrate, allowing for precise alignment and physical/electrical connection using a deformable transfer member and external forces like pressure or heat.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If polymer stamping or transfer using electrostatic or electromagnetic force is used, then micro-LEDs can be transferred from mother substrate to target substrate, but transfer yield is low and device failure risk increases
Solution Approach 1:
The patent replaces complex electrostatic or electromagnetic transfer systems with a simple vacuum-based mechanical adsorption system. The vacuum holder creates negative pressure to adsorb the micro-LED array directly onto the holder surface, eliminating the need for complex electrostatic generators or electromagnetic coils while achieving reliable transfer with high yield.
Solution Approach 2:
The patent extracts the micro-LED array from the mother substrate by creating vacuum adsorption on the holder, separating the transfer function from complex bonding processes. The micro-LEDs are held on the vacuum holder through simple vacuum pressure, allowing clean extraction and transfer without damaging the devices.
2Productivity
If electromagnetic transfer module is used, then micro-LEDs can be transferred, but transfer must be performed at least two times and transfer yield is low
Solution Approach 1:
The patent combines multiple transfer operations into a single vacuum adsorption step. The vacuum holder simultaneously adsorbs the entire micro-LED array in one operation, eliminating the need for sequential transfers required by electromagnetic methods. This single-step process improves both productivity and reliability.
3Ease of manufacture
If conventional micro-LED transfer methods are used, then micro-LEDs can be mounted on substrate, but the process is time-consuming and costly
Solution Approach 1:
The patent performs preliminary vacuum adsorption of the micro-LED array onto the holder before alignment and transfer to the target substrate. This preliminary positioning simplifies subsequent steps and enables parallel processing of multiple arrays, reducing overall manufacturing time and cost.
Solution Approach 2:
The vacuum holder serves multiple functions: it adsorbs micro-LED arrays, holds them during transport, enables alignment, and facilitates transfer to target substrates. This multi-functional tool eliminates the need for separate equipment for each operation, reducing manufacturing complexity and cost.
4Reliability
If transfer member with irreversible property is used, then micro-LEDs can be bonded to target substrate, but the transfer process cannot be repeated several times with the same transfer member
Solution Approach 1:
The patent uses dynamic vacuum control to enable the transfer member (vacuum holder) to be reusable. By applying vacuum to adsorb micro-LEDs and then releasing vacuum to release them, the holder can repeatedly perform transfer operations. The dynamic switching between adsorption and release states allows the same holder to serve multiple transfer cycles.
Solution Approach 2:
The patent recovers the vacuum holder after each transfer by releasing the vacuum, allowing the holder to be reused for subsequent transfers. Instead of discarding the transfer member after single use, the system recovers and reuses the vacuum holder, significantly improving productivity and reducing costs.
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
Enables efficient and cost-effective transfer and assembly of micro-LEDs onto target substrates, facilitating the creation of large-sized RGB displays with improved transfer yield and reduced pressure requirements, thus overcoming the limitations of existing technologies.
Implementation Method 1
vacuum suction force-based easy transfer and assembly of RGB micro-light-emitting diodes
Implementation Method 2
detaching the micro-light-emitting diodes from the mother substrate using selective micro-vacuum adsorption
Implementation Method 3
deforming the transfer member by pressing with a roll or applying external force
Data Source
AI summary
The present disclosure provides a method for transfer and assembly of RGB micro-light-emitting diodes using vacuum suction force whereby the vacuum state of micrometer-sized adsorption holes to which micro-light-emitting diodes formed on a mother substrate or a temporary substrate are bonded is controlled selectively, so that only the micro-light-emitting diode devices desired to be detached from the mother substrate or the temporary substrate are detached from the mother substrate or the temporary substrate using vacuum suction force and then transferred to a target substrate.