Ring Gate Thin Film Transistor Electrostatic Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The electrostatic control capacity of existing thin film transistors over the channel is weak, leading to a large subthreshold swing and slow charging or discharging speed, which affects the performance of display devices.
Innovation Solution
A thin film transistor design featuring a ring-shaped first gate electrode with an active layer having a third portion disposed obliquely, where at least part of the channel is located on the inner side of the gate electrode, enhancing electrostatic control and reducing subthreshold swing. The design includes a channel assistant layer and multiple gate electrodes to improve voltage control and prevent short circuits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a conventional thin film transistor structure is used, then the device is simple to manufacture, but the electrostatic control capacity of the gate electrode over the channel is weak, resulting in a large subthreshold swing and slow charging or discharging speed
Solution Approach 1:
The gate electrode is segmented into multiple parts: a first gate electrode (ring-shaped), a second gate electrode (on inner side of active layer), and a gate bottom. This segmentation allows each gate component to independently contribute to electrostatic control of different regions of the channel, thereby improving overall control capacity and charging/discharging speed without requiring a complete structural overhaul
Solution Approach 2:
The second gate electrode is nested within the inner side of the third portion of the active layer, and the gate bottom is positioned beneath the channel assistant layer. This nested configuration enables multi-layer electrostatic control where inner and outer gate electrodes work synergistically to enhance the electric field distribution over the channel, improving subthreshold swing characteristics
2Reliability
If the gate electrode is positioned to improve electrostatic control, then the subthreshold swing decreases, but the risk of short circuit between gate electrode and drain electrode increases
Solution Approach 1:
The gate bottom is extended into a third dimension beneath the channel assistant layer, creating a vertical separation between the gate electrode structure and the drain electrode. This dimensional change allows the gate to maintain strong electrostatic control over the channel while physically preventing direct contact or short circuits with the drain electrode
Solution Approach 2:
The channel assistant layer serves as an intermediary structure positioned between the gate bottom and the drain electrode. This intermediate layer provides both electrical isolation to prevent short circuits and mechanical support to maintain the precise positioning of the gate structure relative to the channel, ensuring reliable electrostatic control without harmful direct contact
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 enhanced electrostatic control capacity results in a lower subthreshold swing, increasing the charging or discharging speed and improving the display performance of thin film transistors and display devices.
Implementation Method 1
The subthreshold swing is associated with the electrostatic control capacity of the gate electrode of a thin film transistor over the channel, and when the electrostatic control capacity of the gate electrode over the channel is strong, the change value of the gate voltage corresponding to the current change per ten times is small
Data Source
AI summary
A thin film transistor, an array substrate and manufacturing method thereof, and a display device are provided. The thin film transistor includes an active layer, a source electrode, a drain electrode, and a first gate electrode, the first gate electrode is shaped in a ring. The active layer includes a first portion, a second portion and a third portion for connecting the first portion and the second portion. The first portion and the second portion are disposed horizontally, and connected to the source electrode and the drain electrode, respectively. The third portion is disposed obliquely, and has a channel provided thereon. At least one part of the channel is located on an inner side of the first gate electrode. The thin film transistor can be used in a display device.