Staggered OLED Sub-pixel Mask Design for Fabrication Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

High-resolution OLED display devices face challenges in maintaining mechanical stability of fine masks during fabrication, leading to cross-contamination of organic light emitting materials and reduced product yield due to susceptibility to deformation.

Innovation Solution

A new pixel arrangement mode with staggered sub-pixels and a modified mask design featuring a metal bridge and larger openings to enhance mask stability and prevent color mixing, allowing for improved resolution and production efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a fine mask with small openings is used to achieve high resolution, then the resolution improves, but the mechanical stability of the mask deteriorates due to susceptibility to deformation

Engineering Contradiction:
ImproveresolutionVSAvoidmask mechanical stability
Core Design Contradiction:
Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The mask structure is segmented into multiple independent components: a rigid support substrate and separate opening regions formed by removing material. This segmentation allows the openings to be small for high resolution while the support substrate maintains mechanical stability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The mask employs a composite structure combining a rigid support substrate (providing mechanical stability) with opening regions (enabling high resolution). This composite design resolves the contradiction by integrating materials with complementary properties - the rigid substrate prevents deformation while the removed material creates precise small openings for high-resolution patterning.

Inventive Principle:
Principle #40Composite materials

2Stability of the object's composition

If the mask structure is made more rigid to improve mechanical stability, then the mask stability improves, but the aperture ratio deteriorates due to larger supporting structures

Engineering Contradiction:
Improvemask mechanical stabilityVSAvoidaperture ratio
Core Design Contradiction:
Stability of the object's compositionVSArea of moving object

Solution Approach 1:

The mask is segmented into a minimal support framework and discrete opening regions. This segmentation allows the support structure to be sufficiently rigid for mechanical stability while occupying minimal area, thereby maintaining a high aperture ratio for efficient light transmission and material deposition.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The composite mask design uses a rigid support substrate that provides mechanical stability with minimal material volume. The opening regions are precisely defined by material removal rather than added structures, ensuring that the rigid support does not excessively reduce the aperture ratio.

Inventive Principle:
Principle #40Composite materials

3Ease of manufacture

If traditional pixel arrangement is used, then the fabrication process is simple, but cross-contamination occurs due to mask deformation

Engineering Contradiction:
Improvefabrication simplicityVSAvoidcolor mixing prevention
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The mask design segments the opening regions spatially with sufficient separation, preventing material deposited for one sub-pixel from contaminating adjacent sub-pixels. This segmentation maintains fabrication simplicity while eliminating cross-contamination issues that arise from mask deformation in traditional designs.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3226298B1Organic electroluminescence display device and related apparatus
Publication Date: 2023.05.10 BOE TECHNOLOGY GROUP CO LTD
  • EP3226298B1 patent drawingFigure 1
  • EP3226298B1 patent drawingFigure 2
  • EP3226298B1 patent drawingFigure 3

AI summary

An organic light emitting diode display device and a display apparatus, and a mask for fabricating a sub-pixel of the organic light emitting diode display device are provided. Each pixel unit group (11) includes a first sub-pixel unit group (111) and a second sub-pixel unit group (112) which are disposed adjacently along a first direction and include three sub-pixels of different colors, respectively; and the three sub-pixels in the first sub-pixel unit group (111) and the three sub-pixels in the second sub-pixel unit group (112) are staggered along a second direction, and a color of any sub-pixel on a base substrate 10 is different from a color of any other sub-pixel adjacent to the sub-pixel. The organic light emitting diode display device ensures that the sub-pixels of a same color are staggered regularly on the base substrate, which increases strength of the mask, and is conducive to fabrication of the sub-pixel of a small size, so that the resolution of the organic light emitting diode display device can be improved.