Dual-Gate Oxide Semiconductor Transistor for Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices with oxide semiconductor transistors face challenges in achieving high reliability and maintaining excellent electrical characteristics, particularly in terms of on-state current, field-effect mobility, and threshold voltage stability under stress conditions.
Innovation Solution
A dual-gate transistor design is implemented, where an oxide semiconductor film is positioned between two gate electrodes, with the gate electrodes' side surfaces positioned outside the oxide semiconductor film, and the oxide semiconductor film includes indium (In), gallium (Ga), aluminum (Al), yttrium (Y), zirconium (Zr), lanthanum (La), cerium (Ce), or neodymium (Nd), and zinc (Zn), using a sputtering target with a higher indium proportion to enhance performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single-gate transistor structure is used, then the device complexity is low, but the on-state current and field-effect mobility are insufficient
Solution Approach 1:
The transistor gate is segmented into two separate gate electrodes (first gate electrode and second gate electrode) positioned on opposite sides of the oxide semiconductor film. This segmentation allows independent control of the channel from both sides, enhancing carrier mobility and on-state current while maintaining manageable structural complexity through modular design
Solution Approach 2:
The dual-gate structure transitions from a conventional single-plane gate configuration to a three-dimensional arrangement where gate electrodes are positioned on opposite sides of the semiconductor film. This dimensional change enables enhanced electric field control and improved electrical characteristics without proportionally increasing device footprint
2Reliability
If oxide semiconductor layers are stacked to improve carrier mobility, then field-effect mobility increases, but the manufacturing precision requirements increase
Solution Approach 1:
Instead of stacking multiple oxide semiconductor layers vertically, the invention segments the gate control into two separate gate electrodes positioned on opposite sides of a single oxide semiconductor film. This approach achieves enhanced carrier mobility through dual-sided electric field control without the alignment precision challenges of multi-layer stacking
Solution Approach 2:
The solution moves from vertical layer stacking to a three-dimensional dual-gate configuration where gate electrodes are positioned on opposite sides of the film. This dimensional transition achieves improved electrical characteristics while avoiding the manufacturing precision issues associated with multi-layer alignment
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 improves the on-state current, field-effect mobility, and reduces the variation in electrical characteristics, leading to higher reliability and stability of the transistor, with a smaller change in threshold voltage over time, even under stress conditions.
Implementation Method 1
a sputtering target in which the proportion of In is higher than or equal to that of M in an atomic ratio
Data Source
AI summary
A semiconductor device includes a dual-gate transistor in which an oxide semiconductor film is provided between a first gate electrode and a second gate electrode. In the channel width direction of the transistor, a side surface of each of the first and second gate electrodes is on the outer side of a side surface of the oxide semiconductor film. The first or second gate electrode faces the side surface of the oxide semiconductor film with the gate insulating film provided between the first or second gate electrode and the oxide semiconductor film.