Flexible Oxide-Substrate Display Structure With Lower Moisture Permeation

Solution Overview

Problem

Existing display devices face issues with moisture permeation and parasitic capacitance, particularly in flexible substrates like plastic, which affect reliability and manufacturing costs.

Innovation Solution

Utilizing a transparent conductive oxide layer or an oxide semiconductor layer as a substrate to minimize moisture permeation and parasitic capacitance, while enhancing flexibility and reducing manufacturing complexity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a plastic substrate is used to achieve flexibility, then the display device can be folded or rolled, but moisture permeation increases and parasitic capacitance increases

Engineering Contradiction:

ImproveflexibilityVSAvoidmoisture permeation characteristic

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent changes the substrate material from plastic to transparent conductive oxide (TCO) or oxide semiconductor, fundamentally altering the material parameters to achieve both flexibility and reduced moisture permeation. The thin film structure (50-200 nm) of the TCO/oxide semiconductor substrate enables flexibility while the inorganic material properties provide barrier characteristics against moisture

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite material structures where TCO or oxide semiconductor layers are combined with other functional layers (active layer, gate electrode, source/drain electrodes) to create a multi-layer flexible display device. The oxide semiconductor layer serves dual purposes as both substrate and semiconductor material, reducing overall device complexity

Inventive Principle:

Principle #40Composite materials

2Adaptability or versatility

If a plastic substrate is used to achieve flexibility, then the display device can be folded or rolled, but parasitic capacitance increases affecting transistor reliability

Engineering Contradiction:

ImproveflexibilityVSAvoidparasitic capacitance

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the substrate material from plastic to transparent conductive oxide (TCO) or oxide semiconductor, fundamentally altering the material parameters to achieve both flexibility and reduced moisture permeation. The thin film structure (50-200 nm) of the TCO/oxide semiconductor substrate enables flexibility while the inorganic material properties provide barrier characteristics against moisture

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite material structures where TCO or oxide semiconductor layers are combined with other functional layers (active layer, gate electrode, source/drain electrodes) to create a multi-layer flexible display device. The oxide semiconductor layer serves dual purposes as both substrate and semiconductor material, reducing overall device complexity

Inventive Principle:

Principle #40Composite materials

3Adaptability or versatility

If a plastic substrate is used, then the display device can be manufactured with flexible materials, but the manufacturing process becomes more complex and costly

Engineering Contradiction:

ImproveflexibilityVSAvoidmanufacturing process complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The oxide semiconductor layer serves multiple functions simultaneously: as the substrate providing mechanical support, as the semiconductor material forming the active layer, and as part of the transistor structure. This multi-functionality reduces the number of separate manufacturing steps and material deposition processes required

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the substrate material from plastic to transparent conductive oxide (TCO) or oxide semiconductor, fundamentally altering the material parameters to achieve both flexibility and reduced moisture permeation. The thin film structure (50-200 nm) of the TCO/oxide semiconductor substrate enables flexibility while the inorganic material properties provide barrier characteristics against moisture

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12568757B2Display device

Publication Date: 2026.03.03 LG DISPLAY CO LTD

AI summary

A display device includes a substrate which includes an active area including a plurality of sub pixels and a non-active area, and is formed of one of transparent conductive oxide or an oxide semiconductor layer, an insulating layer on the substrate, a plurality of thin film transistors which is on the insulating layer and includes an active layer having a channel region, a gate electrode, a source electrode, and a drain electrode and a plurality of light emitting diodes disposed in the plurality of sub pixels on the insulating layer, wherein the substrate includes a plurality of holes which overlap with at least a part of the active layer.