Micro-LED Contact Electrode Layout to Prevent Optical Layer Delamination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices experience delamination issues between the optical layer and contact electrodes, leading to cracking in the cathode electrode and misalignment during manufacturing.
Innovation Solution
The transparent conductive layer is removed or omitted from the uppermost surface of the contact electrode in the contact hole area, forming an interface with the optical layer to enhance adhesion and reduce cracking, while using banks with varying sizes and flexible conductive patterns to support proper contact formation and incorporating redundant micro light emitting elements for defect compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a transparent conductive layer is present on the uppermost surface of the contact electrode in the contact hole area, then electrical conductivity is improved, but delamination occurs between the optical layer and contact electrode
Solution Approach 1:
The transparent conductive layer is selectively removed from the uppermost surface of the contact electrode in the contact hole area, extracting the problematic layer that causes delamination while preserving it in other areas where it provides electrical conductivity
Solution Approach 2:
The contact electrode structure is made non-uniform: the transparent conductive layer is present in areas where electrical conductivity is needed but removed in the contact hole area where direct contact between the optical layer and contact electrode is required for proper adhesion
2Reliability
If the transparent conductive layer is removed from the contact hole area, then adhesion is enhanced and cracking is reduced, but manufacturing complexity increases
Solution Approach 1:
The transparent conductive layer is removed in advance during the manufacturing process before subsequent layers are deposited, preventing adhesion issues and cracking in later stages
3Manufacturing precision
If standard contact electrode structure is used, then manufacturing process is simple, but alignment accuracy deteriorates during manufacturing
Solution Approach 1:
The contact electrode structure is locally modified in the contact hole area to improve alignment accuracy during manufacturing, with the removed transparent conductive layer creating a distinct interface for precise positioning
Data Source
AI summary
The disclosure discloses a display device including a substrate, a circuit layer disposed on the substrate, and a plurality of banks disposed on the circuit layer. A plurality of light-emitting elements is disposed on the banks, each having a first electrode and a second electrode. A contact electrode is disposed on the bank and is electrically connected to the first electrode. The contact electrode includes a contact opening. An optical layer covers side surfaces of the plurality of light-emitting elements and the contact electrode, and includes a contact hole aligned with the contact opening of the contact electrode. The contact electrode is electrically connected with the second electrode through the contact hole of the optical layer. A transparent conductive layer is not present in the region of electrical connection between the contact electrode and the second electrode. This structure improves adhesion and maintains the structural integrity of the optical layer.