Display Pad Electrode Layout to Prevent Encapsulation Residue

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing display devices face issues with the exposure of pads during manufacturing, which can lead to damage and hinder proper connection with lighting inspection electrodes, and the residual encapsulation layer often remains on the pad electrodes, affecting the integrity and functionality of the display device.

Innovation Solution

The display device incorporates a middle layer to cover the side of the pad electrode, uses a separate connection electrode to connect the pad electrode with the lighting inspection electrode, and employs a manufacturing method that includes laser treatment and selective etching to prevent exposure and residual encapsulation layer formation on the pad electrode.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the pad electrode is positioned in the non-display area near the substrate edge for signal input and lighting inspection, then the connectivity and inspection functionality are improved, but the pad electrode side becomes exposed and vulnerable to damage

Engineering Contradiction:

Improveconnectivity and inspection functionalityVSAvoidpad exposure and damage risk

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The middle layer extends in the vertical dimension to cover the side surface of the pad electrode, transitioning from a two-dimensional planar structure to a three-dimensional protective structure. This dimensional extension effectively shields the exposed pad side without affecting its electrical connectivity function.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The middle layer acts as an intermediary protective element between the pad electrode and the external environment. It mediates the conflict between exposing the pad for connectivity/inspection and protecting it from damage, by providing physical coverage while maintaining electrical functionality.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the encapsulation layer is formed to cover the light emitting element, then the protection and encapsulation functionality are improved, but residual encapsulation layer remains on the pad electrode affecting integrity

Engineering Contradiction:

Improveencapsulation and protection functionalityVSAvoidresidual encapsulation layer on pad electrode

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The middle layer is selectively positioned only in the non-display area where the pad electrode is located, while the encapsulation layer covers the display area with the light emitting element. This local differentiation allows the encapsulation layer to provide protection where needed without leaving harmful residues on the pad electrode.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The device structure is segmented into display area and non-display area, with different layer configurations in each region. The middle layer is specifically added in the non-display area to prevent encapsulation layer residue on the pad electrode, while maintaining proper encapsulation in the display area.

Inventive Principle:

Principle #1Segmentation

3Reliability

If the connection electrode is used to connect pad electrode with lighting inspection electrode, then the electrical connectivity is improved, but the device complexity increases

Engineering Contradiction:

Improveelectrical connectivityVSAvoidnumber of electrodes and connections

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The middle layer serves multiple functions simultaneously: it covers and protects the pad electrode side, prevents encapsulation layer residue, and allows electrical connection between the pad electrode and lighting inspection electrode through its opening. This merging of protective and connective functions reduces the need for separate connection electrodes.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The middle layer is designed as a multi-functional element that combines protection, encapsulation prevention, and electrical connectivity functions. By making the middle layer universal in its functionality, the patent reduces overall device complexity while maintaining reliable electrical connections.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 approach effectively prevents pad exposure and damage, ensuring smooth connection with lighting inspection electrodes and avoids residual encapsulation layer presence, enhancing the reliability and functionality of the display device.

Implementation Method 1

after removing the connection electrode, processing the substrate with a laser may be further included

Methodology Applied

Scientific EffectLaser: Laser

Data Source

PatentUS20250374677A1Display device and manufacturing method of the same

Publication Date: 2025.12.04 SAMSUNG DISPLAY CO LTD

AI summary

A display device includes a substrate including a display area and a non-display area, a light emitting element positioned in the display area and an encapsulation layer overlapping the light emitting element and a plurality of pad electrodes positioned in the non-display area of the substrate, wherein the side of the pad electrode facing the edge of the substrate is covered with an interlayer, the residual layer of the encapsulation layer is not positioned on the upper surface of the pad electrode, and the residual layer of the encapsulation layer is positioned in the area between the pad electrodes in the non-display area.