Display Substrate Contact Pad Insulation for Etching Control

Solution Overview

Problem

The increasing resolution and narrowing bezel of OLED display devices lead to reduced pixel sizes, causing issues such as metal residue and etching loss in the backplane circuit, resulting in short circuits and poor display performance, particularly in the bonding region.

Innovation Solution

A display substrate design with a first insulation layer located between contact pads to protect the edges of metal layers, preventing etching and stripping during manufacturing, and ensuring proper contact with external circuits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If pixel size is reduced to increase resolution, then display resolution is improved, but metal residue and etching loss occur causing short circuits

Engineering Contradiction:

Improvedisplay resolutionVSAvoidcircuit reliability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent applies preliminary action by forming a protective insulation layer on the metal layers before the etching process. This insulation layer is deposited in advance to prevent etching solution from contacting and damaging the metal layers, thereby preventing short circuits caused by metal residue and etching loss while maintaining high resolution displays

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses an insulation layer as an intermediary substance between the etching solution and the metal layers. This intermediate layer acts as a barrier that protects the metal conductors from direct exposure to the etching solution, preventing harmful chemical reactions and ensuring circuit reliability during the manufacturing process

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If pixel size is reduced to increase resolution, then display resolution is improved, but manufacturing precision deteriorates due to etching loss

Engineering Contradiction:

Improvedisplay resolutionVSAvoidmetal layer precision

Core Design Contradiction:

Measurement precisionVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by forming a protective insulation layer on the metal layers before the etching process. This insulation layer is deposited in advance to prevent etching solution from contacting and damaging the metal layers, thereby preventing short circuits caused by metal residue and etching loss while maintaining high resolution displays

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses an insulation layer as an intermediary substance between the etching solution and the metal layers. This intermediate layer acts as a barrier that protects the metal conductors from direct exposure to the etching solution, preventing harmful chemical reactions and ensuring circuit reliability during the manufacturing process

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If contact pads are exposed without insulation, then electrical connection is improved, but etching and stripping of metal layers occur

Engineering Contradiction:

Improveelectrical connectionVSAvoidetching and stripping

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by selectively forming an insulation layer only in specific regions where metal layer protection is needed, while leaving other areas exposed for electrical connection. The insulation layer is locally deposited on the metal layers in the bonding region to protect them from etching and stripping, while maintaining electrical connectivity where required

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses an insulation layer as an intermediary substance between the etching solution and the metal layers. This intermediate layer acts as a barrier that protects the metal conductors from direct exposure to the etching solution, preventing harmful chemical reactions and ensuring circuit reliability during the manufacturing process

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS20250255128A1Display substrate and manufacturing method thereof, and display device

Publication Date: 2025.08.07 CHENGDU BOE OPTOELECTRONICS TECH CO LTD

AI summary

A display substrate and a manufacturing method thereof, and a display device are disclosed. The display substrate includes a base substrate, a plurality of sub-pixels, at least one group of contact pads, and a first insulation layer. The base substrate includes a display region and a bonding region located at one side of the display region. At least one group of contact pads includes a plurality of contact pads, at least one of the plurality of contact pads includes a first contact pad metal layer and a second contact pad metal layer, the second contact pad metal layer covers an edge of the first contact pad metal layer. The first insulation layer is located in gaps between the plurality of contact pads and covers edges of the plurality of contact pads, and is configured to expose surfaces of the plurality of contact pads facing away from the base substrate.