Pixel Definition Layer Gap Design for Display Deposition Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices face challenges in deposition accuracy and reliability due to variations in shadow areas and pixel position accuracy during the manufacturing process, leading to defects and reduced performance.
Innovation Solution
A display device design with a pixel definition layer featuring specific gaps between light emitting openings, calculated based on the difference in shadow area size and pixel position accuracy, to compensate for deposition process errors and improve reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the pixel definition layer uses uniform gaps between light emitting openings, then the manufacturing process is simple, but deposition accuracy deteriorates due to shadow area variations and pixel position deviations
Solution Approach 1:
The pixel definition layer employs non-uniform gap widths tailored to specific locations. The first gap width differs from the second gap width based on their respective positions and the shadow areas they accommodate. This local differentiation ensures that each gap is optimized for its specific deposition requirements, thereby improving overall deposition accuracy without applying a complex uniform design across the entire structure.
Solution Approach 2:
The gap widths in the pixel definition layer are pre-calculated and designed to compensate for anticipated shadow area variations and pixel position deviations before the deposition process begins. By establishing these differentiated gaps in advance, the design proactively addresses potential deposition inaccuracies, ensuring that even with variations in shadow areas and pixel positions, the final light emitting patterns achieve the desired accuracy.
2Reliability
If the mask opening size is increased to cover shadow areas, then deposition coverage improves, but pixel position accuracy deteriorates due to larger deviation ranges
Solution Approach 1:
The pixel definition layer uses differently sized gaps at different locations to locally accommodate shadow areas without uniformly enlarging all mask openings. The first gap and second gap have different widths tailored to their specific shadow area requirements, allowing the design to cover shadow regions while maintaining precise pixel positioning where needed.
Solution Approach 2:
The design changes the gap width parameter of the pixel definition layer based on location-specific requirements. By adjusting the gap widths (first gap width vs. second gap width) according to the shadow areas and pixel positions they serve, the system optimizes both deposition coverage and position accuracy without requiring uniform parameter changes across all openings.
3Manufacturing precision
If multiple deposition processes are performed to ensure coverage, then manufacturing precision improves, but productivity deteriorates due to increased process time
Solution Approach 1:
The pixel definition layer is designed with pre-calculated non-uniform gap widths that anticipate and accommodate shadow area variations and pixel position deviations before deposition occurs. This preliminary optimization allows the light emitting patterns to be deposited accurately in a single process, eliminating the need for multiple deposition steps and thereby maintaining high productivity.
Solution Approach 2:
By changing the gap width parameters of the pixel definition layer to different values (first gap width vs. second gap width) based on location-specific shadow areas and pixel positions, the design enables accurate light emitting pattern formation in one deposition process, avoiding the time-consuming multiple deposition approach.
Data Source
AI summary
A display device includes a circuit layer disposed on a base layer, a pixel definition layer disposed on the circuit layer and provided with first, second, and third light emitting openings, and first, second, and third light emitting elements disposed on the circuit layer and including light emitting patterns disposed in the first, second, and third light emitting openings. The pixel definition layer has a first gap corresponding to a distance between the first and third light emitting openings and a second gap corresponding to a distance between the first and second light emitting openings. A difference between the first gap and the second gap is determined according to a difference in size of a shadow area of at least one of the light emitting patterns and a difference in deviation of a pixel position accuracy (PPA) of the at least one of light emitting patterns.