Display Apparatus Inorganic Layer Roughness Barrier

Solution Overview

Problem

Existing display apparatuses are vulnerable to damage from external oxygen and moisture due to infiltration through the protective layers, despite the presence of a protective layer, as the current designs fail to effectively prevent impurities from reaching the display area.

Innovation Solution

A display apparatus with a substrate having a display area and a peripheral area, featuring a dam and inorganic layers with varying surface roughness to prevent the spread of impurities, where the first inorganic layer has a nonplanar surface with increased roughness outside the dam, and a second inorganic layer covers the dam and organic layer, reducing the likelihood of moisture and oxygen infiltration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a protective layer covers the display devices, then the display devices are protected from oxygen and moisture, but impurities can still infiltrate into the display area causing damage

Engineering Contradiction:

Improveprotection from oxygen and moistureVSAvoidinfiltration of impurities

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The protective structure is divided into multiple functional segments: a dam structure that segments the peripheral area from the display area, a first inorganic layer providing baseline protection, a first organic layer filling gaps and providing additional barrier, and a second inorganic layer sealing the structure. This segmentation allows each layer to address specific infiltration pathways, collectively preventing both oxygen/moisture and impurity infiltration.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The protective structure employs a composite multi-layer system combining inorganic materials (first and second inorganic layers) with organic material (first organic layer). The inorganic layers provide impermeable barriers against oxygen and moisture, while the organic layer fills irregularities and provides additional protection. This composite approach creates a synergistic protective system that blocks multiple types of harmful infiltrations simultaneously.

Inventive Principle:

Principle #40Composite materials

2Device complexity

If a simple protective layer is used, then the device structure is simple, but it fails to prevent impurity infiltration effectively

Engineering Contradiction:

Improvestructure simplicityVSAvoidprotection effectiveness

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The protective structure is divided into multiple functional segments: a dam structure that segments the peripheral area from the display area, a first inorganic layer providing baseline protection, a first organic layer filling gaps and providing additional barrier, and a second inorganic layer sealing the structure. This segmentation allows each layer to address specific infiltration pathways, collectively preventing both oxygen/moisture and impurity infiltration.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The protective structure employs a composite multi-layer system combining inorganic materials (first and second inorganic layers) with organic material (first organic layer). The inorganic layers provide impermeable barriers against oxygen and moisture, while the organic layer fills irregularities and provides additional protection. This composite approach creates a synergistic protective system that blocks multiple types of harmful infiltrations simultaneously.

Inventive Principle:

Principle #40Composite materials

3Area of stationary object

If the organic layer extends to the peripheral area, then complete coverage is achieved, but impurities can spread along the organic layer interface

Engineering Contradiction:

Improvecoverage areaVSAvoidimpurity spread

Core Design Contradiction:

Area of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The inorganic layers exhibit varying local qualities: they have greater thickness and extend further in the peripheral area compared to the display area. The first inorganic layer covers the dam structure and extends into the peripheral area, while the second inorganic layer similarly provides extended coverage at the periphery. This localized enhancement creates a protective barrier that prevents impurity spread along interfaces while maintaining appropriate coverage in the display area.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The solution addresses the two-dimensional spread problem by adding vertical dimensionality through multi-layer stacking. Instead of relying solely on horizontal coverage, the inorganic layers are stacked vertically with the organic layer in between, creating a three-dimensional protective structure. This vertical arrangement blocks impurity spread paths that would otherwise travel along horizontal interfaces.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS10403852B2Display apparatus

Publication Date: 2019.09.03 SAMSUNG DISPLAY CO LTD

AI summary

A display apparatus includes a substrate having a display area and a peripheral area outside the display area, a dam in the peripheral area, a first inorganic layer located in both the display area and the peripheral area and covering the dam, an upper surface of the first inorganic layer being nonplanar, and a roughness of the upper surface at a first part of the first inorganic layer outside the dam being greater than a roughness of the upper surface near a center of the display area, an organic layer covering the first inorganic layer in the display area and a portion of the peripheral area, and a second inorganic layer located in both the display area and the peripheral area and covering the dam and the organic layer.