Oxide Semiconductor Gate Stack With Al Oxide Oxygen Barrier
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor devices using oxide semiconductors face challenges in maintaining stable operation due to oxygen vacancies, which are not adequately addressed by existing methods that either introduce more defects in the insulating layer or fail to supply sufficient oxygen, leading to variations in characteristics and reliability issues.
Innovation Solution
A semiconductor device configuration with a metal oxide layer containing aluminum, positioned between the gate insulating layer and the oxide semiconductor layer, where the metal oxide layer's thickness is between 1 nm and 4 nm, acts as a gas barrier to regulate oxygen and hydrogen, ensuring oxygen vacancies are repaired while minimizing defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an insulating layer with more oxygen is used to supply oxygen to the oxide semiconductor layer, then oxygen vacancies in the oxide semiconductor layer are reduced, but defects in the insulating layer increase causing electron-trapping and variation in characteristics
Solution Approach 1:
A metal oxide layer is introduced as an intermediary between the insulating layer and the oxide semiconductor layer. This intermediate layer acts as a buffer that supplies oxygen to the oxide semiconductor layer without requiring the insulating layer to have high oxygen content, thereby preventing electron-trapping defects in the insulating layer while still reducing oxygen vacancies in the semiconductor layer.
Solution Approach 2:
The structure is segmented into multiple functional layers: the insulating layer, the metal oxide layer, and the oxide semiconductor layer. This segmentation allows each layer to perform its specific function independently - the insulating layer provides electrical isolation, the metal oxide layer supplies oxygen, and the oxide semiconductor layer provides the active channel, resolving the contradiction between oxygen supply and defect reduction.
2Quantity of substance
If the metal oxide layer thickness is increased to improve oxygen supply, then more oxygen can be supplied to the oxide semiconductor layer, but the electron-trapping effect and characteristic variation increase due to more defects
Solution Approach 1:
The thickness of the metal oxide layer is precisely controlled within the range of 1 nm to 4 nm. This parameter optimization ensures sufficient oxygen supply to the oxide semiconductor layer while maintaining low defect concentration. The specific thickness range balances oxygen diffusion capability with minimal electron-trapping, resolving the contradiction between oxygen quantity and reliability.
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 enhances the mobility and reliability of the semiconductor device by effectively supplying oxygen to the oxide semiconductor layer, improving initial characteristics and reliability test results.
Implementation Method 1
the metal oxide layer's thickness is between 1 nm and 4 nm, acts as a gas barrier to regulate oxygen and hydrogen
Data Source
AI summary
A semiconductor device according to an embodiment includes: a substrate; a metal oxide layer arranged above the substrate and having aluminum as the main component of the metal oxide layer; an oxide semiconductor layer arranged above the metal oxide layer; a gate electrode facing the oxide semiconductor layer; and a gate insulating layer between the oxide semiconductor layer and the gate electrode, wherein a thickness of the metal oxide layer is 1 nm or more and 4 nm or less.