OLED Evaporation Mask Self-Alignment via Electroforming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current mask manufacturing technologies for OLED display devices face challenges in achieving high resolution due to alignment issues during photoresist exposure and the high cost of metal master plates, with existing methods limiting the precision and morphology of evaporation openings.
Innovation Solution
A method of manufacturing a mask with a self-alignment effect using a metal layer and photoresist patterns, where a second photoresist pattern is formed in recessed regions of the metal layer, allowing for accurate alignment of evaporation sub-openings without a metal master plate, and utilizing electroforming to reduce costs and improve precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional photoresist exposure and metal master plate methods are used, then mask manufacturing can be performed, but alignment precision is insufficient and manufacturing cost is high
Solution Approach 1:
The patent uses a metal layer as a copy or replica of the photoresist pattern, where the metal layer is formed by electroforming based on the photoresist structure. This metal copy serves as a precise template for creating the final mask, eliminating the need for expensive metal master plates while maintaining high alignment precision through the self-alignment effect between the photoresist pattern and metal layer
Solution Approach 2:
The patent implements a self-alignment effect where the metal layer automatically aligns with the photoresist pattern during the electroforming process. The metal layer forms raised regions corresponding to the photoresist structures, creating automatic positioning without requiring additional alignment steps or expensive master plates, thus improving precision while reducing manufacturing complexity
2Manufacturing precision
If metal master plates are used, then high precision can be achieved, but manufacturing cost increases significantly
Solution Approach 1:
The patent replaces expensive metal master plates with a disposable photoresist pattern that serves as a template. The photoresist pattern is formed, used to create the metal layer through electroforming, and then discarded, eliminating the need for costly metal master plates while maintaining sufficient precision for evaporation opening formation
Solution Approach 2:
The patent creates a metal copy of the photoresist pattern through electroforming, where the metal layer replicates the photoresist structure's geometry. This metal copy is then used to form the evaporation openings, providing high precision without requiring the original expensive metal master plate, thus reducing manufacturing cost while maintaining precision
3Shape
If conventional mask manufacturing methods are used, then production can proceed, but the morphology of evaporation openings is limited
Solution Approach 1:
The patent changes the geometric parameters of the evaporation openings by controlling the thickness and shape of the metal layer and photoresist structures. The metal layer is formed with specific thickness variations that correspond to different opening sizes, allowing precise control over evaporation opening morphology and size while maintaining manufacturing feasibility
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
The method enhances the precision and reduces the manufacturing cost of the mask, enabling the formation of flare-shaped evaporation openings that meet the requirements of OLED display devices, improving the accuracy and reducing the cost of the mask production.
Implementation Method 1
forming a metal layer covering the first photoresist pattern on the substrate formed with the first photoresist pattern by an electroforming process
Implementation Method 2
forming a first photoresist pattern on the substrate, the first photoresist pattern comprising a plurality of photoresist structures arranged in an array
Data Source
AI summary
A mask and a method of manufacturing the same, an evaporation apparatus and a display device are provided. The method includes forming a first photoresist pattern on a substrate, the first photoresist pattern including a plurality of photoresist structures, each photoresist structure including a first surface away from the substrate and a second surface near the substrate, and the size of the first surface being smaller than that of the second surface; forming a metal layer on the substrate with the first photoresist pattern, the metal layer including a plurality of recessed regions and a plurality of raised regions; forming a second photoresist pattern in the recessed regions, an orthographic projection of the second photoresist pattern on the metal layer overlapping with the recessed regions; removing regions of the metal layer not covered by the second photoresist pattern, the second photoresist pattern, the substrate and the first photoresist pattern mask.