Display Bank Layer Blocking for Quantum Dot Thickness Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Display devices face challenges in maintaining a constant thickness of functional layers, such as quantum dot layers, due to losses in the bank layer, leading to irregular color conversion and potential defects like dark or bright spots in the display area.

Innovation Solution

A display device design that includes a blocking layer to separate central and adjacent openings in the bank layer, ensuring the functional layer is filled with a consistent thickness, and a method to repair lost portions of the bank layer by forming a blocking layer on the connection portion and removing excess using laser radiation or inkjet printing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the bank layer is continuous without repair, then the manufacturing process is simple, but the functional layer cannot be filled with constant thickness leading to display defects

Engineering Contradiction:

Improvefunctional layer thickness uniformityVSAvoidbank layer structure

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The bank layer is segmented into separate regions by introducing a blocking layer that divides the continuous bank layer into first and second banks. This segmentation prevents the functional layer from flowing between adjacent openings, ensuring constant thickness in each opening while maintaining overall structural organization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A blocking layer is introduced as an intermediary element between the central opening and adjacent openings. This blocking layer acts as a barrier that prevents the functional layer material from migrating between openings, thereby ensuring uniform thickness without requiring complete isolation of each opening.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Manufacturing precision

If a blocking layer is added to separate openings, then the functional layer thickness is constant, but the device complexity increases

Engineering Contradiction:

Improvefunctional layer thickness uniformityVSAvoidnumber of layers

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The blocking layer is strategically placed only at specific connection portions where openings are adjacent to each other, rather than isolating every opening completely. This local application of the blocking structure achieves the necessary thickness control while minimizing the overall increase in device complexity.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

Instead of completely isolating each opening with individual barriers, the solution uses partial blocking at connection portions. This partial action is sufficient to prevent functional layer migration while avoiding the excessive complexity of complete isolation structures.

Inventive Principle:

Principle #16Partial or excessive action

3Manufacturing precision

If laser radiation is used to remove excess blocking layer, then the repair precision is high, but the manufacturing complexity increases

Engineering Contradiction:

Improveblocking layer removal precisionVSAvoidrepair process steps

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The mechanical or chemical removal processes are replaced with laser radiation for removing excess blocking layer. This substitution enables precise, contactless removal with high spatial resolution, achieving superior precision while the automated nature of laser processing reduces manual intervention complexity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 solution maintains the functional layer's thickness and color conversion function, preventing defects and improving the reliability and uniformity of the display device's color output.

Implementation Method 1

a blocking layer overlapping the connection portion, and a functional layer including at least one selected from a quantum dot and a scatterer, where the functional layer fills the central opening in which a connection to the adjacent opening is blocked by the blocking layer

Methodology Applied

Scientific EffectPhysical barrier blocking:

Implementation Method 2

removing excess using laser radiation

Methodology Applied

Scientific EffectLaser ablation: Laser Ablation

Data Source

PatentUS12058912B2Display device and method of repairing the display device

Publication Date: 2024.08.06 SAMSUNG DISPLAY CO LTD

AI summary

A display device includes: a lower substrate; a display element on the lower substrate and including an emission layer; an upper substrate on the lower substrate with the display element therebetween, where the upper substrate includes a central area overlapping the display element and an adjacent area adjacent to the central area; a bank layer on a lower surface of the upper substrate facing the lower substrate, where a central opening overlapping the central area, an adjacent opening overlapping the adjacent area, and a connection portion connecting the central opening and the adjacent opening to each other are defined in the bank layer; a blocking layer overlapping the connection portion; and a functional layer including at least one selected from a quantum dot and a scatterer, where the functional layer fills the central opening in which a connection to the adjacent opening is blocked by the blocking layer.