Oxide Semiconductor TFT With Intermediate Transition Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The stability of oxide semiconductor TFT properties is not consistently achieved in existing technologies due to interface states generated between oxide semiconductor films with different compositions, leading to unreliable performance.
Innovation Solution
A semiconductor device with an oxide semiconductor TFT featuring a layered structure including an In-Ga-Zn oxide semiconductor layer with a continuously changing composition intermediate transition layer, formed using the plasma MOCVD method to reduce residual methyl groups and enhance film quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a stacked semiconductor layer with two oxide semiconductor films of different compositions is formed, then TFT mobility is improved, but interface states are generated between layers leading to unstable TFT properties
Solution Approach 1:
An intermediate transition layer is introduced between the first and second oxide semiconductor layers. This intermediate layer has a composition that continuously changes from the composition of the first layer to the composition of the second layer, acting as a mediator that reduces interface states and enables stable TFT operation while maintaining high mobility
2Reliability
If an intermediate transition layer with continuously changing composition is introduced, then interface state impacts are mitigated and TFT stability is improved, but device structure complexity increases
Solution Approach 1:
The composition of the intermediate transition layer continuously changes from the first layer to the second layer, creating a gradient structure that mitigates interface states. This parameter change approach achieves stable TFT properties while managing structural complexity through controlled compositional variation
3Manufacturing precision
If plasma MOCVD method is used to form the oxide semiconductor layer, then residual methyl groups are reduced and film quality is enhanced, but manufacturing process complexity increases
Solution Approach 1:
The plasma MOCVD method replaces conventional deposition methods to form the oxide semiconductor layer. This substitution reduces residual methyl groups in the film and enhances film quality, achieving high manufacturing precision through plasma-based chemical vapor deposition
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 solution provides a highly reliable oxide semiconductor TFT with improved stability and performance by mitigating interface state impacts and reducing residual methyl group concentrations, resulting in enhanced film quality and increased mobility.
Implementation Method 1
formed using the plasma MOCVD method
Data Source
AI summary
A semiconductor device includes a substrate and an oxide semiconductor TFT supported by the substrate. The oxide semiconductor TFT includes an oxide semiconductor layer containing In, Ga, and Zn, a gate electrode, a gate insulating layer formed between the gate electrode and the oxide semiconductor layer, and a source electrode and a drain electrode that are in contact with the oxide semiconductor layer. The oxide semiconductor layer has a layered structure that includes a first layer, a second layer, and an intermediate transition layer disposed between the first layer and the second layer, and the first layer is disposed closer to the gate insulating layer side than the second layer. The first layer and the second layer have different compositions, and the intermediate transition layer has a continuously changing composition from the first layer side toward the second layer side.