OLED Pixel Defining Layer Formation Using Active Array Masking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The conventional manufacturing process for organic light-emitting diode (OLED) display panels is complex and costly, requiring a specific mask plate and precise positioning, which affects yield due to the complexity of the producing flow.

Innovation Solution

A method that eliminates the need for a specific mask plate by using the scan lines, data lines, driving power lines, switch transistors, and connecting lines as a mask during the photolithography process to form the pixel defining layer, simplifying the process and reducing production costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a specific mask plate and positioning process are used to form the pixel defining layer, then the pixel defining layer can be formed with accurate positioning, but the manufacturing process becomes complex and production costs increase

Engineering Contradiction:
Improvepositioning accuracy of pixel defining layerVSAvoidcomplexity of manufacturing process
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The existing opaque structures (data lines, scan lines, transistors) on the substrate serve as their own mask patterns during photolithography. By coating photoresist on the substrate and exposing it from the opposite side, these existing structures automatically define the pixel defining layer pattern without requiring external mask plates, thus eliminating positioning processes and simplifying the manufacturing flow

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The opaque structures in the active array serve dual functions: they act as both the functional circuit elements (data lines, scan lines, transistors) and as the mask patterns for defining pixels. This multi-functionality eliminates the need for separate mask plates and positioning processes, reducing manufacturing complexity while maintaining precision

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Manufacturing precision

If a specific mask plate and positioning process are used to form the pixel defining layer, then the pixel defining layer can be formed with accurate positioning, but production costs increase

Engineering Contradiction:
Improvepositioning accuracy of pixel defining layerVSAvoidproduction cost
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The existing opaque structures (data lines, scan lines, transistors) on the substrate serve as their own mask patterns during photolithography. By coating photoresist on the substrate and exposing it from the opposite side, these existing structures automatically define the pixel defining layer pattern without requiring external mask plates, thus eliminating positioning processes and simplifying the manufacturing flow

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The method replaces expensive, reusable mask plates with a simple photoresist coating process that uses the substrate's existing structures as masks. This eliminates the need for costly mask plate fabrication, storage, and positioning infrastructure, significantly reducing production costs

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Manufacturing precision

If a specific mask plate and positioning process are used to form the pixel defining layer, then the pixel defining layer can be formed with accurate positioning, but the production yield is affected by positioning precision

Engineering Contradiction:
Improvepositioning accuracy of pixel defining layerVSAvoidproduction yield
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The existing opaque structures (data lines, scan lines, transistors) on the substrate serve as their own mask patterns during photolithography. By coating photoresist on the substrate and exposing it from the opposite side, these existing structures automatically define the pixel defining layer pattern without requiring external mask plates, thus eliminating positioning processes and simplifying the manufacturing flow

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The photoresist layer acts as an intermediary that transfers the pattern from the opaque structures to the pixel defining layer. During exposure from the opposite side, the photoresist automatically aligns with the underlying opaque structures, eliminating the need for precise mask positioning and reducing yield losses from misalignment

Inventive Principle:
Principle #24Intermediary (Mediator)

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 simplifies the manufacturing flow, decreases production costs, and increases yield by eliminating the need for a specialized mask plate and precise positioning, resulting in a more efficient production process for OLED display panels.

Implementation Method 1

performing exposure on the photoresist layer from one side of the transparent substrate opposed to the photoresist layer, wherein a pattern constituted by the scan lines, the data lines, the driving power lines, the connecting lines, the switch transistors and the driving transistors is used as a mask plate to prevent exposure of the corresponding photoresist

Methodology Applied
Scientific EffectPhotopolymerization: Photopolymerisation

Data Source

PatentEP2680073B1Method of manufacturing an organic light-emitting diode display panel
Publication Date: 2020.08.05 BOE TECHNOLOGY GROUP CO LTD
  • EP2680073B1 patent drawingFigure 1~2
  • EP2680073B1 patent drawingFigure 3~4
  • EP2680073B1 patent drawingFigure 5

AI summary

Embodiments of the present invention provide an organic light emitting diode display panel and a method for manufacturing the same. The manufacturing method comprises: coating a photoresist layer on a transparent substrate with an active array formed; performing exposure on the photoresist layer from one side of the transparent substrate opposed to the photoresist layer, where the scan lines and the at least one kind of lines are used as a mask to prevent exposure of the corresponding photoresist, so that a photoresist remaining region is formed by the photoresist layer; conducting a development treatment on the photoresist layer, so that the photoresist outside the photoresist remaining region is removed and the photoresist in the photoresist remaining region is retained to form the pixel defining layer. The embodiments of the invention may simplify the fabricating flow of the display panel, reduce production costs of the display panel, and increase yield of the display panel.