Decoupled Gate Electrodes in Display Panels for Low-Resistance Scan Lines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transistors with oxide layers in display devices face challenges in achieving high field-effect mobility and reliability while minimizing gate capacitance and reducing the resistance of scan lines, which complicates high-density pixel arrangement and increases manufacturing costs.
Innovation Solution
A display device configuration featuring a first transistor with a metal gate electrode and a second transistor with a metal oxide gate electrode, where the gate electrodes are not connected, reducing gate capacitance and allowing for low-resistance scan lines without increasing manufacturing costs, by using a metal material for the first gate electrode and a metal oxide material for the second gate electrode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an oxide layer is used as a top gate electrode to achieve high reliability through oxygen release, then reliability is improved, but the resistance of the gate electrode and scan line increases
Solution Approach 1:
The gate electrode is divided into two separate gates: a first gate electrode made of metal material and a second gate electrode made of oxide semiconductor material. This segmentation allows each gate to fulfill different functions - the first gate provides low resistance for scan lines, while the second gate provides oxygen release for reliability, thereby resolving the contradiction between low resistance and high reliability
Solution Approach 2:
Different materials are used for different parts of the gate structure. The first gate electrode uses metal material specifically where low resistance is needed (scan line connection), while the second gate electrode uses oxide semiconductor material where oxygen release is needed (channel region). This local differentiation of material properties resolves the contradiction between low resistance and high reliability
2Object-affected harmful factors
If a metal wiring is stacked over the gate electrode to reduce scan line resistance, then resistance is reduced, but the number of steps increases and manufacturing cost increases
Solution Approach 1:
The first gate electrode made of metal material serves dual functions: it acts as the gate electrode for the transistor and simultaneously serves as the scan line wiring. This multi-functionality eliminates the need for separate metal wiring layers, reducing the number of manufacturing steps while maintaining low resistance
Solution Approach 2:
The scan line wiring function is merged with the first gate electrode structure. Instead of stacking metal wiring over the gate electrode, the first gate electrode itself is formed from metal material that can function as both gate and wiring, thereby combining two functions into one structure and reducing manufacturing complexity
3Reliability
If a top gate structure with oxide layer is used to achieve high field-effect mobility, then field-effect mobility is improved, but gate capacitance becomes excessively increased
Solution Approach 1:
The single top gate structure is segmented into two separate gates: a first gate electrode and a second gate electrode. This segmentation allows the electric field to be distributed between two gates rather than concentrated in one thick oxide layer, thereby maintaining high field-effect mobility while reducing excessive gate capacitance
Solution Approach 2:
The gate structure parameters are changed from a single thick oxide layer to two thinner gate electrodes with different materials. This parameter change maintains the necessary electric field strength for high mobility while distributing the capacitance load, thereby resolving the contradiction between high mobility and low capacitance
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 effectively reduces gate capacitance, maintains high reliability, and enables high-density pixel arrangement without increasing manufacturing costs by decoupling the gate electrodes and using appropriate materials for the gate electrodes.
Implementation Method 1
a gate electrode that is formed with, for example, an oxide layer and releases oxygen by being heated
Data Source
AI summary
A novel display device or the like in which a transistor connected to a scan line has small gate capacitance is provided. A novel display device or the like in which a scan line has low resistance is provided. A novel display device or the like in which pixels can be arranged with high density is provided. A novel display device or the like that can be manufactured without an increase in cost is provided. In a transistor including a first gate electrode and a second gate electrode, the first gate electrode is formed using a metal material with low resistance and the second gate electrode is formed using a metal oxide material that can reduce oxygen vacancies in an oxide semiconductor layer. The first gate electrode is connected to the scan line, and the second gate electrode is connected to a wiring to which a constant potential is supplied.