Protective Layer for Common Electrode Line in Display Devices

Solution Overview

Problem

The manufacturing process of display devices, particularly for flat panel displays like LCDs and OLEDs, often damages the common electrode line due to repeated patterning, leading to IR-drop issues and reduced performance.

Innovation Solution

A protective layer is applied to at least part of the end portion of the common electrode line, which is made of metal and extends beyond the display area, with specific dimensions and materials matching the planarization layer, to prevent damage and ensure uniform layer formation during manufacturing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If repeated patterning is performed in the manufacturing process, then the display device can be manufactured with required precision, but the common electrode line is damaged

Engineering Contradiction:

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

A protective layer is introduced as an intermediary element between the patterning process and the common electrode line. This protective layer absorbs the mechanical and chemical stresses of repeated patterning operations, preventing direct damage to the common electrode line while allowing the patterning process to proceed with required precision.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The protective layer is applied beforehand to the common electrode line before the repeated patterning process begins. This pre-protection measures cushioning effect, where the protective layer is designed to withstand and dissipate the stresses that will be encountered during subsequent patterning operations, thereby preventing damage to the underlying common electrode line.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Productivity

If the common electrode line is damaged, then manufacturing can proceed, but IR-drop issues occur and performance is reduced

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The protective layer serves as a preventive measure that cushions the common electrode line against damage during manufacturing. By maintaining the integrity of the common electrode line, the protective layer ensures that electrical performance and low IR-drop characteristics are preserved, eliminating the need for rework or replacement of damaged lines.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Device complexity

If no protective layer is used, then the manufacturing process is simpler, but the common electrode line is vulnerable to damage

Engineering Contradiction:

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The protective layer acts as an intermediary protective element that is integrated into the manufacturing process. While it adds one additional process step, the protective layer is applied using standard coating techniques and can be patterned along with other layers, thereby minimizing the increase in overall process complexity while significantly improving common electrode line durability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS10777586B2Display device and method for manufacturing the same

Publication Date: 2020.09.15

AI summary

A display device including a substrate including a display area and a non-display area, a common electrode line in the non-display area, and a protective layer coating at least a part of an end portion of the common electrode line.