OLED Pad Area Insulation Cutouts to Block Crack Propagation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting diode (OLED) display devices face issues with crack propagation and potential short circuits due to the presence of an organic layer between input and output pads, which can lead to corrosion and reliability concerns.
Innovation Solution
Incorporating inorganic insulating layers with cutout portions in the intermediate area between input and output pad areas, specifically a first and second cutout portion near each pad area, to prevent crack propagation and reduce the risk of short circuits and corrosion, while maintaining the structural integrity and display quality of the OLED device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If inorganic insulating layers are continuously formed between input and output pads, then electrical insulation is improved, but crack propagation and corrosion risk increase due to the organic layer presence
Solution Approach 1:
The patent removes portions of the inorganic insulating layers to form cutout portions in the intermediate area between input and output pads. This extraction of the insulating layer material eliminates the continuous path that would allow crack propagation through the organic layer, while still maintaining electrical insulation through the remaining insulating layer portions and the substrate structure.
Solution Approach 2:
The inorganic insulating layers are segmented by creating cutout portions that divide the continuous insulating structure into separate regions. This segmentation prevents cracks from propagating continuously across the pad area, as the cutout portions act as barriers to crack propagation paths.
2Reliability
If inorganic insulating layers are removed to prevent crack propagation, then reliability is improved, but electrical insulation and structural integrity may be compromised
Solution Approach 1:
The inorganic insulating layers are selectively removed only in the intermediate area between input and output pads, while being maintained in other critical areas. This local modification provides crack propagation resistance where needed without compromising the overall structural integrity and electrical insulation of the device.
Solution Approach 2:
The cutout portions in the inorganic insulating layers act as intermediary structures that manage the stress distribution and crack propagation paths. By creating these controlled void spaces, the structure can accommodate thermal expansion and mechanical stress without developing catastrophic cracks, thereby maintaining structural integrity while improving reliability.
3Reliability
If cutout portions are created in inorganic insulating layers, then crack propagation is blocked, but manufacturing complexity increases
Solution Approach 1:
The inorganic insulating layers are designed with predetermined patterns that facilitate the creation of cutout portions during the manufacturing process. The layer structure and material selection are optimized in advance to enable selective removal through standard fabrication techniques, reducing the complexity of the manufacturing process while achieving the desired crack propagation resistance.
Data Source
AI summary
A display device includes: a substrate including: a display area; and a pad area including: an input pad area; an output pad area spaced apart from the input pad area in a first direction, and an intermediate area between the input pad area and the output pad area; and inorganic insulating layers defining a cutout portion in the intermediate area.