Display Pad Electrode Protection via Etch Rate Differential
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The reliability of flat panel display devices is compromised due to damage of pad electrodes during the etching process, which affects the display's performance and manufacturing costs.
Innovation Solution
A display device design that includes a substrate with a display area and a pad area, featuring a thin film encapsulation layer, a protective film with inorganic materials, and a light transmitting film with etched openings, where the etch rate of the protective film is lower than the light transmitting film, ensuring the pad electrodes are protected during etching and internalizing light blocking patterns to control viewing angles, reduce power consumption, and minimize thickness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the etching process is used to form light blocking patterns, then light transmission control is improved, but pad electrodes are damaged
Solution Approach 1:
A protective film is formed over the pad electrodes before the etching process to prevent damage. This preliminary protective action ensures that when etching is subsequently performed to create light blocking patterns, the pad electrodes remain intact and undamaged.
Solution Approach 2:
The protective film is selectively positioned only in the pad area where damage risk exists, while allowing the etching process to proceed freely in the display area to form light blocking patterns. This localized protection approach addresses the specific vulnerability of pad electrodes without interfering with the light transmission control function.
2Length of stationary object
If light blocking patterns are internalized in the display panel, then thickness is reduced, but manufacturing complexity increases
Solution Approach 1:
The light blocking patterns are integrated directly into the display panel structure by forming them within the encapsulation layers, merging the light control function with the existing panel architecture. This eliminates the need for separate light blocking components and reduces overall thickness.
Solution Approach 2:
The light blocking patterns are formed during the encapsulation process before final assembly, utilizing the encapsulation layers as the medium for pattern formation. This preliminary integration simplifies the overall manufacturing流程 by combining multiple functions into a single structural element.
3Reliability
If a protective film with low etch rate is used, then pad electrodes are protected during etching, but etching time increases
Solution Approach 1:
The protective film with low etch rate is applied only in the pad area where protection is needed, while the rest of the structure undergoes normal etching. This localized approach to using low-etch-rate material minimizes the overall etching time impact while providing necessary protection to pad electrodes.
Solution Approach 2:
The protective film is formed as a preliminary layer before the main etching process, allowing for selective protection during etching. The film's low etch rate property is utilized specifically in regions requiring protection, enabling the etching process to proceed efficiently in other areas without compromising pad electrode integrity.
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 solution enhances the reliability of the display device by preventing pad electrode damage, reducing power consumption, and lowering manufacturing costs while maintaining control over viewing angles.
Implementation Method 1
an etch rate of the protective film may be lower than an etch rate of the light transmitting film in a same etching process
Data Source
AI summary
A display device includes a substrate including a display area and a pad area disposed outside a display area in plan view, a plurality of pixels disposed in a display area on a substrate, at least one display pad electrode disposed in a pad area on a substrate, a thin film encapsulation layer disposed on a display area on a substrate and covering the plurality of pixels, a protective film disposed on a thin film encapsulation layer and including an inorganic material, a light transmitting film disposed on a protective film and including a plurality of openings exposing a portion of a protective film, and a light blocking pattern that fills each of the plurality of openings and are disposed on a protective film.