Dual-Gate Oxide Semiconductor Transistor for Threshold Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor devices, particularly transistors with oxide semiconductor layers, face challenges in controlling threshold voltage and achieving excellent electrical characteristics such as on-state current and field-effect mobility, while also requiring improved reliability and drive frequency.
Innovation Solution
A transistor design featuring an oxide semiconductor layer with a surrounded channel structure, incorporating a first and second gate electrode and insulating layers, allows for controlled threshold voltage and enhanced electrical characteristics by ensuring effective electric field application and mechanical strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single-gate transistor structure is used, then the device complexity is reduced, but the threshold voltage control and electrical characteristics are insufficient
Solution Approach 1:
The transistor gate is divided into two separate gates (first gate electrode and second gate electrode) that can be independently controlled. This segmentation allows independent adjustment of voltages applied to each gate, enabling precise threshold voltage control and improved electrical characteristics without significantly increasing overall device complexity.
Solution Approach 2:
The patent introduces a dual-gate configuration where the second gate electrode is positioned on the opposite side of the oxide semiconductor layer from the first gate electrode. This spatial arrangement in another dimension enables effective electric field application across the entire channel region, improving threshold voltage control and electrical characteristics.
2Length of moving object
If the oxide semiconductor layer is made thinner to reduce device size, then miniaturization is achieved, but the mechanical strength and electrical characteristics deteriorate
Solution Approach 1:
The patent combines the functions of two gate electrodes positioned on opposite sides of the oxide semiconductor layer. This merging of gate functions allows for effective electric field application that compensates for the reduced mechanical strength of thinner oxide semiconductor layers, maintaining electrical characteristics while achieving miniaturization.
Solution Approach 2:
By changing the voltage parameters applied to the first and second gates independently, the patent optimizes the electric field distribution across the thin oxide semiconductor layer. This parameter adjustment enables maintenance of electrical characteristics and mechanical strength despite reduced layer thickness.
3Speed
If the oxide semiconductor layer is made thinner to improve frequency characteristics, then the drive frequency is improved, but the on-state current and reliability worsen
Solution Approach 1:
The dual-gate configuration segments the electric field control, allowing independent optimization of voltage parameters for each gate. This enables enhancement of frequency characteristics through rapid switching while maintaining on-state current through proper voltage application to both gates, resolving the trade-off between speed and reliability.
Solution Approach 2:
The patent employs a composite structure with oxide semiconductor layer sandwiched between two gate insulating layers, each with the second gate electrode. This composite configuration enables simultaneous improvement of frequency characteristics and on-state current by effectively controlling carrier transport and accumulation in the thin oxide semiconductor layer.
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 design achieves improved on-state current characteristics, frequency performance, and reliability by effectively applying electric fields to the oxide semiconductor layer, enabling miniaturization and high mechanical strength.
Implementation Method 1
The first gate electrode faces the oxide semiconductor layer with the first insulating layer interposed therebetween. The second gate electrode faces the oxide semiconductor layer with the second insulating layer interposed therebetween
Data Source
AI summary
A transistor with excellent electrical characteristics (e.g., on-state current, field-effect mobility, or frequency characteristics) is provided. The transistor includes an oxide semiconductor layer including a channel formation region, a first gate electrode, a second gate electrode, a source electrode, and a drain electrode. The oxide semiconductor layer is between the first gate electrode and the second gate electrode. The oxide semiconductor layer has a pair of side surfaces in contact with the source electrode and the drain electrode and includes a region surrounded by the first gate electrode and the second gate electrode without the source electrode and the drain electrode interposed therebetween.