Copper Concentration Gradient Thin Film Transistor Gray Scale Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thin film transistors used in display devices have limitations in achieving a large s-factor, which is crucial for representing gray scales effectively, due to their material properties and fabrication processes.
Innovation Solution
A thin film transistor with a surface defect state is created by disposing Cu ions on the active layer and heat-treating the surface, resulting in a concentration gradient of copper ions that enhances the s-factor, allowing for improved gray scale representation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional thin film transistor fabrication processes are used, then the manufacturing process is simple, but the s-factor is insufficient for effective gray scale representation
Solution Approach 1:
Cu ions are disposed on the active layer surface before final device completion, and heat treatment is performed in advance to create the desired concentration gradient. This preliminary action establishes the defect state that will enhance the s-factor in the final device without requiring complex post-processing steps.
Solution Approach 2:
The invention changes the concentration parameter of Cu ions within the active layer by controlling the heat treatment temperature (200-400°C) and duration. This parameter change creates a concentration gradient that generates the desired defect state, improving the s-factor from conventional levels to 0.2 or more.
2Manufacturing precision
If Cu ions are disposed on the active layer surface and heat treatment is performed, then the s-factor increases to 0.2 or more, but the fabrication process becomes more complex
Solution Approach 1:
The heat treatment temperature is optimized within the range of 200-400°C to achieve the desired Cu ion concentration gradient. This parameter optimization ensures that the s-factor reaches 0.2 or more while keeping the process within standard fabrication capabilities, balancing manufacturing ease with performance improvement.
3Ease of operation
If a concentration gradient of copper ions is created in the active layer, then the s-factor is enhanced for better gray scale control, but the manufacturing precision requirements increase
Solution Approach 1:
The heat treatment temperature and duration are controlled within specific ranges (200-400°C for controlled time periods) to achieve the desired Cu ion concentration gradient. This controlled parameter change creates a reproducible defect state that enhances gray scale control while maintaining achievable manufacturing precision.
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 approach results in a thin film transistor with an s-factor of 0.2 or more, enabling better control over the drain-source current and thus enhancing the display device's ability to represent gray scales with improved display quality.
Implementation Method 1
disposing Cu ions on the surface and heat-treating the surface of the active layer
Data Source
AI summary
A thin film transistor for a display device includes an active layer, and a gate electrode spaced apart from the active layer and at least partially overlapping with the active layer, wherein the active layer includes copper, and has a concentration gradient of copper along a thickness direction of the active layer.