Semiconducting Oxide and Silicon TFT Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electronic device displays with thin-film transistors often face issues such as excessive leakage current, insufficient drive strength, poor area efficiency, hysteresis, and non-uniformity, which affect the performance of organic light-emitting diode displays.
Innovation Solution
The use of semiconducting oxide transistors and silicon transistors in pixel circuits, combined with storage capacitors and a stepped dielectric layer profile, allows for improved control of current flow and light emission in organic light-emitting diode displays, while flexible substrates enable bending without damage, minimizing inactive border regions and enhancing display performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional thin-film transistors are used in display pixel circuits, then the display can be manufactured with standard processes, but the transistors exhibit excessive leakage current and insufficient drive strength
Solution Approach 1:
The transistor gate is segmented into two independent gates (first gate and second gate), allowing separate control of threshold voltage and drive current. This segmentation enables the transistor to achieve both low leakage current (through threshold voltage control) and high drive strength (through independent drive control) while maintaining compatibility with standard thin-film transistor manufacturing processes
Solution Approach 2:
The invention changes the electrical parameters of the transistor by applying different voltages to the two gates. The first gate controls threshold voltage to minimize leakage, while the second gate controls drive current to enhance switching capability. This parameter control approach resolves the contradiction between reliability and ease of manufacture by achieving superior electrical performance through voltage modulation rather than process complexity
2Adaptability or versatility
If rigid substrates are used for displays, then manufacturing and assembly are simplified, but the display cannot be bent or folded
Solution Approach 1:
The invention replaces rigid substrates with flexible substrates that enable the display to be bent or folded. The thin-film transistor structures and pixel circuits are deposited directly onto these flexible substrates using standard deposition techniques, maintaining manufacturing simplicity while achieving the desired flexibility and adaptability for foldable or wearable display applications
3Area of moving object
If large inactive border regions are present in flexible displays, then the bending radius can be reduced, but the effective display area is minimized
Solution Approach 1:
The invention moves the bending functionality to the substrate level rather than requiring large inactive border regions at the display panel level. By using flexible substrates with appropriate thickness and mechanical properties, the display can achieve small bending radii without sacrificing active display area, as the flexibility is inherent to the substrate material rather than being provided by large inactive regions
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
This configuration enhances the performance of organic light-emitting diode displays by reducing leakage current, improving drive strength, and ensuring uniformity, while allowing for flexible and damage-resistant designs that minimize inactive border regions.
Implementation Method 1
Each pixel circuit may include an organic light-emitting diode and a drive transistor coupled to that organic light-emitting diode
Data Source
AI summary
An electronic device display may have an array of pixel circuits. Each pixel circuit may include an organic light-emitting diode and a drive transistor. Each drive transistor may be adjusted to control how much current flows through the organic light-emitting diode. Each pixel circuit may include one or more additional transistors such as switching transistors and a storage capacitor. Semiconducting oxide transistors and silicon transistors may be used in forming the transistors of the pixel circuits. The storage capacitors and the transistors may be formed using metal layers, semiconductor structures, and dielectric layers. Some of the layers may be removed along the edge of the display to facilitate bending. The dielectric layers may have a stepped profile that allows data lines in the array to be stepped down towards the surface of the substrate as the data lines extend into an inactive edge region.