Display Electrode Insulation Layout for Precise Inkjet Emission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During the manufacturing process of display devices, electrodes are prone to damage due to exposure to developers, leading to issues such as lifting or breaking.
Innovation Solution
A display device design that includes a substrate with a via layer, electrodes, insulating layers, and a bank layer with barrier and bank portions, where the first insulating layer completely covers the electrodes to prevent developer contact, and the second insulating layer overlaps only the barrier portions, ensuring the bank portion remains uncovered to prevent ink overflow during inkjet printing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the first insulating layer completely covers the electrodes, then electrode damage from developer exposure is prevented, but the bank portion becomes covered which may cause ink overflow during inkjet printing
Solution Approach 1:
The bank layer is divided into barrier portions and bank portions with different thicknesses. The barrier portions (thinner) are covered by the first insulating layer to protect electrodes, while the bank portions (thicker) remain exposed for accurate inkjet printing. This segmentation allows simultaneous achievement of electrode protection and printing precision.
Solution Approach 2:
Different regions of the bank layer are given different thicknesses to serve different functions. The barrier portions have sufficient thickness to prevent developer damage when covered, while the bank portions have greater thickness to remain uncovered and guide ink placement. This local differentiation resolves the contradiction between protection and precision.
2Reliability
If the second insulating layer overlaps the barrier portions, then electrode protection is maintained, but overlapping the bank portion would cause ink overflow
Solution Approach 1:
The second insulating layer is positioned to overlap only the barrier portions of the bank layer, not the bank portions. This selective overlapping protects the electrode regions while leaving the ink-guiding bank portions exposed, preventing both developer damage and ink overflow.
Solution Approach 2:
The barrier portions serve as an intermediary structure that can be covered by insulating layers without affecting inkjet printing. They provide a protective interface between the electrodes and the inkjet printing process, allowing the second insulating layer to overlap them safely.
3Ease of manufacture
If the bank layer has uniform thickness, then manufacturing is simplified, but both barrier and bank portions would need different coverage to achieve the desired protection and printing precision
Solution Approach 1:
The bank layer employs non-uniform thickness with distinct barrier portions and bank portions. This local quality variation enables the first insulating layer to provide comprehensive electrode protection while the second insulating layer selectively covers only barrier portions, achieving both protection and printing precision without excessive complexity.
Data Source
AI summary
A display device includes: a substrate; a via layer on the substrate; a first electrode and a second electrode on the via layer and spaced apart from each other; a first insulating layer on the first electrode and the second electrode; a bank layer on the first insulating layer and having barrier portions and a bank portion having a greater thickness than the barrier portions; a second insulating layer on the bank layer and the first insulating layer, the second insulating layer overlapping the barrier portions and not overlapping the bank portion; light emitting elements on the second insulating layer and on the first electrode and the second electrode; and a first connection electrode contacting an end of each light emitting element and a second connection electrode contacting another end of the light emitting elements.