Level Difference Moderating Layer for Flexible Display Wire Reliability

Solution Overview

Problem

Flexible display devices, such as organic electroluminescence (EL) and liquid crystal displays, face issues with wire disconnection near the bending regions due to mechanical stress, which existing technologies have not adequately addressed.

Innovation Solution

A display device design that includes a base material with an insulating layer and a level difference moderating layer, composed of semiconductor and/or metal materials, extending from the display region to the bending region to mitigate wire disconnection, along with a manufacturing method that forms these layers to enhance structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a flexible display device is designed with a bending region to enable flexibility, then the adaptability and versatility of the display device is improved, but wire disconnection occurs near the bending region due to mechanical stress

Engineering Contradiction:

ImproveflexibilityVSAvoidwire connection reliability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

A level difference moderating layer is introduced as an intermediary component between the insulating layer and the base material in the bending region. This layer mediates the mechanical stress concentration that would otherwise cause wire disconnection, allowing the display device to maintain both flexibility and wire connection reliability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The level difference moderating layer is applied selectively only in the bending region rather than uniformly across the entire display device. This localized approach addresses the specific problem of wire disconnection in the bending area while maintaining the overall flexibility of the device, without unnecessarily modifying other regions.

Inventive Principle:

Principle #3Local quality

2Reliability

If a level difference moderating layer is added to suppress wire disconnection, then the reliability of wire connection is improved, but the device complexity increases

Engineering Contradiction:

Improvewire connection reliabilityVSAvoidlayer structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The level difference moderating layer is applied selectively only in the bending region rather than uniformly across the entire display device. This localized approach addresses the specific problem of wire disconnection in the bending area while maintaining the overall flexibility of the device, without unnecessarily modifying other regions.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The level difference moderating layer is formed using the same material and process as the insulating layer (through etching and deposition), effectively creating a simplified copy of the existing layer structure. This reduces the complexity of introducing a new layer type while still achieving the stress-moderating function.

Inventive Principle:

Principle #26Copying

3Manufacturing precision

If the insulating layer extends to the edge of the base material, then the manufacturing precision is improved, but the level difference at the edge causes wire disconnection in the bending region

Engineering Contradiction:

Improveinsulating layer alignmentVSAvoidwire connection reliability

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

A level difference moderating layer is introduced as an intermediary component between the insulating layer and the base material in the bending region. This layer mediates the mechanical stress concentration that would otherwise cause wire disconnection, allowing the display device to maintain both flexibility and wire connection reliability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The level difference moderating layer is formed beforehand in the bending region to cushion against the mechanical stress that will occur during bending operations. This preventive measure addresses potential wire disconnection issues before the device is actually bent and used.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentUS10134828B2Display device and method of manufacturing a display device

Publication Date: 2018.11.20 MAGNOLIA WHITE CORP

AI summary

A display device according to an embodiment of the present invention includes: a base material including a display region, and a peripheral region which is located outside the display region, at least a part of the peripheral region being a bending region; an insulating layer that is disposed on the base material, extends from the display region to a part of the peripheral region, and is located apart from an edge of the base material; at least one level difference moderating layer that is disposed under the insulating layer and extends from an edge of the insulating layer toward a side of the bending region; and at least one wiring disposed on the insulating layer and the at least one level difference moderating layer.