OLED Deposition Mask With Variable Thickness Dummy Patterns
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mask assemblies used in organic light emitting display manufacturing are prone to deformation due to tensile forces, which complicates the patterning of organic emission layers and makes it difficult to maintain isolation from moisture and oxygen.
Innovation Solution
A mask assembly with a mask main body of varying thickness, including active patterns and dummy patterns, is designed to absorb and spread tensile forces, maintaining rigidity and controlling deformation. The mask assembly features a frame with openings and multiple masks arranged in a band shape, where the active patterns have a smaller thickness than the main body, and dummy patterns with intermediate thicknesses are placed between active patterns and the mask edges, distributing the tensile force effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a mask assembly is used for depositing organic layers in OLED manufacturing, then precise patterning can be achieved, but the mask deforms due to tensile forces applied during the process
Solution Approach 1:
The mask is divided into multiple independent active patterns separated from each other, allowing each pattern to be supported independently by the frame. This segmentation prevents cumulative deformation across the entire mask and enables localized stability control for each patterning region.
Solution Approach 2:
Different regions of the mask have different thicknesses - the active patterns have a first thickness optimized for patterning precision, while the areas between patterns have a second thickness that provides structural support and resistance to tensile forces. This local quality variation allows the mask to simultaneously achieve precision and stability.
2Stability of the object's composition
If the mask main body thickness is reduced to minimize deformation, then flexibility increases, but the rigidity required to maintain pattern integrity is compromised
Solution Approach 1:
The mask employs a local quality principle by varying the thickness across different regions. The active pattern areas maintain a thinner first thickness to minimize deformation, while the inter-pattern regions have a thicker second thickness to provide the necessary rigidity and strength against tensile forces, thus achieving both deformation control and structural integrity.
Solution Approach 2:
The mask can be constructed using composite material structures with varying thickness profiles, combining regions of different mechanical properties. This allows the thinner active pattern regions to remain flexible and resistant to deformation, while the thicker support regions provide the required rigidity and strength.
3Reliability
If dummy patterns are added to absorb tensile forces, then active pattern stability improves, but the mask structure becomes more complex
Solution Approach 1:
The dummy patterns are strategically placed only in the regions between active patterns where tensile forces are most problematic. This localized approach provides the necessary force absorption and support without adding complexity to the entire mask structure, maintaining simplicity in the active patterning regions while enhancing stability in the support regions.
Data Source
AI summary
A mask for deposition includes a mask main body extended in a first direction and having a first thickness, and including ends opposite to each other in the first direction and supported by a frame while a tensile force is applied to the mask in the first direction; and a plurality of active patterns separated from each other in the first direction in a center area of the mask main body, and having a second thickness less than the first thickness.