Micro LED Pad and Protection Bump Layout for Laser Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The transfer technology for micro light emitting diodes (LEDs) is prone to machine operating errors and alignment inaccuracies, leading to yield losses and operational issues due to incorrect placement of micro LEDs on circuit boards.
Innovation Solution
The implementation of a light-emitting diode design that includes a first and second semiconductor layer, pads, and a protection bump, where the pads are electrically connected and the protection bump is strategically positioned to improve the accuracy of the laser transfer process, preventing rotation issues and ensuring proper alignment during the transfer from one substrate to another.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If mechanical transfer technology is used to transfer micro LEDs, then the transfer process can be automated, but machine operating errors and alignment inaccuracies occur leading to yield loss
Solution Approach 1:
The patent introduces an alignment mark structure as an intermediary element between the micro LED and the transfer system. This alignment mark serves as a mediator that enables precise positioning during the automated transfer process, allowing the machine to accurately locate and transfer micro LEDs without direct mechanical contact, thereby resolving the contradiction between automation and precision
Solution Approach 2:
The patent replaces traditional mechanical alignment and transfer methods with a laser-based transfer approach. The laser transfer system uses optical fields instead of mechanical contact to transfer micro LEDs, eliminating mechanical operating errors and improving alignment accuracy while maintaining automation
2Productivity
If mechanical transfer technology is used to transfer micro LEDs, then the transfer process can be performed, but placement accuracy deteriorates due to machine operating errors and alignment errors
Solution Approach 1:
The alignment mark structure acts as an intermediary reference that enables the laser transfer system to accurately determine the position and orientation of micro LEDs. This intermediary element allows high-speed automated transfer while maintaining precise placement accuracy by providing optical reference points for positioning
Solution Approach 2:
The patent replaces mechanical transfer methods with laser-based transfer, substituting mechanical positioning with optical field-based positioning. This substitution enables both high productivity through automated laser transfer and high placement accuracy through optical alignment, resolving the contradiction between productivity and precision
3Device complexity
If micro LEDs are placed without alignment marks, then the device structure is simpler, but placement accuracy deteriorates due to lack of reference points
Solution Approach 1:
The alignment mark structure serves multiple functions simultaneously: it provides alignment reference points for the laser transfer system, acts as a positioning guide during transfer, and enables accuracy compensation. This multi-functionality justifies the added structural complexity by delivering significant improvements in placement accuracy and transfer reliability
Data Source
AI summary
A light emitting diode includes a first semiconductor layer, a second semiconductor layer, a first pad, a second pad, and a protection bump. The first semiconductor layer and the second semiconductor layer are overlapping with each other. An area of a first surface of the first semiconductor layer is larger than an area of a second surface of the second semiconductor layer. The first surface faces the second surface. The first pad is electrically connected to the first semiconductor layer. The second pad is electrically connected to the second semiconductor layer. The protection bump is located between the first pad and the second pad.