OLED Encapsulation Layer Local Quality Design for Crack Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting display devices face significant challenges due to moisture and oxygen permeation, which can lead to cracks in the encapsulation layer during the scribing process, compromising the device's integrity and performance.
Innovation Solution
A multi-layer encapsulation structure is implemented, where inorganic films are strategically deposited only in the inner portion of the inactive area adjacent to the active area, avoiding the outer portion to minimize damage from impacts during cutting, and an organic film is used to cover the inorganic films, creating a barrier that prevents moisture and oxygen ingress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If inorganic films are deposited in the outer portion of the inactive area, then moisture and oxygen permeation is suppressed, but cracks occur during the scribing process due to impacts
Solution Approach 1:
The patent applies different material properties to different regions of the encapsulation structure. Inorganic films are deposited only in the inner portion of the inactive area where moisture barrier is critical, while the outer portion near the scribing line uses only organic films that are more flexible and impact-resistant. This local differentiation resolves the contradiction by providing strong barrier properties where needed without compromising overall structural integrity during scribing.
Solution Approach 2:
The encapsulation structure is segmented into distinct regions: an inner portion with inorganic films for moisture barrier and an outer portion with only organic films for impact absorption. This segmentation allows each region to perform its specialized function, preventing cracks from propagating into the inorganic film layers during the scribing process while maintaining effective moisture and oxygen barrier properties in the active area.
2Reliability
If inorganic films are deposited to cover the entire inactive area, then permeation protection is enhanced, but manufacturing complexity and damage risk increase
Solution Approach 1:
The patent implements selective inorganic film deposition only in the inner portion of the inactive area adjacent to the active area, rather than covering the entire inactive area. This localized approach reduces manufacturing complexity and the number of deposition steps required, while still providing sufficient permeation protection for the critical regions containing the organic light emitting element.
3Reliability
If inorganic films are used in the outer portion, then barrier performance is improved, but impact damage from scribing increases
Solution Approach 1:
The patent strategically places inorganic films only in the inner portion of the inactive area where barrier performance is most critical for protecting the organic light emitting element, while deliberately excluding the outer portion near the scribing line. The outer portion uses only organic films that can absorb scribing impacts without cracking, thus resolving the contradiction between barrier performance and impact resistance.
Solution Approach 2:
The organic film layer in the outer portion acts as a cushioning layer before impacts occur during scribing. This softer, more flexible material absorbs and dissipates impact energy, preventing cracks from forming and propagating into the more fragile inorganic film layers in the inner portion, thereby protecting the overall encapsulation structure from damage.
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 suppresses moisture and oxygen permeation, reducing the likelihood of cracks and enhancing the durability and reliability of the organic light emitting display devices by minimizing damage from scribing impacts.
Implementation Method 1
inorganic films are strategically deposited only in the inner portion of the inactive area adjacent to the active area, avoiding the outer portion to minimize damage from impacts during cutting, and an organic film is used to cover the inorganic films, creating a barrier that prevents moisture and oxygen ingress
Implementation Method 2
A multi-layer encapsulation structure is implemented, where inorganic films are strategically deposited only in the inner portion of the inactive area adjacent to the active area, avoiding the outer portion to minimize damage from impacts during cutting
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
Provided is an organic light emitting display device. The organic light emitting device includes: an organic light emitting element layer (112, 114, 116) in an active area (A/A); and an encapsulation layer (120) covering the organic light emitting element layer. The encapsulation layer includes one or more inorganic films (121-1, 121-2) and one or more organic films (122). The one or more inorganic films and the one or more organic films cover the entire active area (A/A) and a part of an inactive area (I/A) surrounding the active area. The one or more inorganic films (121-1, 121-2) are disposed only to a portion having a predetermined inward distance from an outermost periphery of the inactive area.