Crack Blocking Layer in Foldable Display Transistors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Foldable or rollable display devices are prone to cracking due to stress and external impacts, which can propagate through the interface between the insulating layer and semiconductor layer, leading to operational failures.
Innovation Solution
A display device with a crack blocking layer made of organic insulating material positioned between the substrate and the second semiconductor layer of the second transistor, preventing crack propagation and maintaining device reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If rigid substrates are used for display devices, then manufacturing precision and structural strength are improved, but flexibility and adaptability deteriorate
Solution Approach 1:
The patent employs flexible thin film layers including the crack blocking layer (500-1000 nm thick), gate insulating layers, and semiconductor layers that can bend and deform without cracking. These thin film structures replace rigid substrates while maintaining structural integrity through their inherent flexibility and plastic deformation capability.
Solution Approach 2:
The patent uses composite material structures combining organic insulating materials with inorganic gate insulating layers. The organic crack blocking layer serves as a flexible matrix that can deform plastically, while the inorganic layers provide functional properties, creating a composite structure that achieves both flexibility and manufacturing precision.
2Adaptability or versatility
If the display device is made foldable or rollable to improve adaptability, then flexibility is improved, but reliability deteriorates due to crack propagation
Solution Approach 1:
The crack blocking layer is positioned between the substrate and the gate insulating layers to preemptively block crack propagation paths. This layer acts as a cushion that absorbs and redistributes stress before cracks can reach critical components like the semiconductor layer and transistor interfaces, preventing reliability failure in advance.
Solution Approach 2:
The organic crack blocking layer serves as an intermediary between the rigid substrate and the fragile semiconductor structures. It mediates the stress transmission, allowing the substrate to be flexible while protecting the semiconductor layers from direct mechanical stress and crack propagation.
3Adaptability or versatility
If multiple transistors with multiple semiconductor layers are used to improve device functionality, then adaptability is improved, but reliability worsens due to increased crack propagation paths
Solution Approach 1:
The patent segments the transistor structure into multiple semiconductor layers (first and second semiconductor layers) with separate gate structures. Each layer is independently protected by the crack blocking layer positioned beneath it, creating segmented protection zones that prevent cracks from propagating across the entire device structure.
Solution Approach 2:
The crack blocking layer introduces a new dimensional element in the vertical stacking sequence, positioned between the substrate and the multi-layer transistor structures. This additional layer creates a new protective dimension that intercepts cracks before they can propagate through the vertical stack of multiple semiconductor layers.
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 crack blocking layer effectively blocks crack propagation to the second transistor, ensuring unique device characteristics and enhancing the reliability of the display device by using ductile materials that deform plastically rather than cracking, thus maintaining performance under stress and impact.
Implementation Method 1
using ductile materials that deform plastically rather than cracking, thus maintaining performance under stress and impact
Data Source
AI summary
A display device includes a substrate including a pixel region and a peripheral region. The display device also includes a plurality of pixels provided in the pixel region for displaying an image. The display device also includes a light emitting element provided in each pixel for emitting light. The display device includes a first transistor provided in each pixel for driving the light emitting element, and a second transistor connected to the first transistor. The display device includes an insulating layer disposed between a second semiconductor layer of the second transistor and the substrate; and a crack blocking layer disposed between the insulating layer and the second semiconductor layer of the second transistor. A first semiconductor layer of the first transistor and the second semiconductor layer of the second transistor are provided in layers different from each other.