Silicon Carbide Interface Layer Structure for Low State Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor devices using silicon carbide face challenges in achieving optimal characteristics due to interface state density and nitrogen termination issues, leading to unreliable insulating films and unwanted oxidation.
Innovation Solution
A semiconductor device structure comprising a silicon carbide member, a first member with silicon and oxygen, a first layer with a silicon-nitrogen bond, and a second layer with silicon-oxygen and silicon-nitrogen bonds, where the first layer acts as a terminal layer and the second layer as a transition layer, reducing interface state density and suppressing oxidation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a silicon oxide film is formed on a silicon carbide layer, then oxidation is suppressed, but interface state density increases and nitrogen termination is poor
Solution Approach 1:
A nitrogen-containing silicon oxide film is introduced as an intermediary layer between the silicon carbide layer and the silicon oxide film. This intermediate film with nitrogen content serves as a mediator that provides both oxidation suppression and improved nitrogen termination at the interface, resolving the contradiction between oxidation protection and interface quality
Solution Approach 2:
The invention uses a composite structure where a nitrogen-containing silicon oxide film is combined with a conventional silicon oxide film. The nitrogen-containing silicon oxide film contains both silicon and nitrogen elements in specific proportions, creating a composite material that simultaneously achieves oxidation suppression and low interface state density
2Reliability
If nitrogen is introduced to improve termination, then nitrogen termination improves, but unwanted nitrogen introduction occurs in the silicon carbide layer
Solution Approach 1:
The nitrogen-containing silicon oxide film is designed with specific local composition characteristics where nitrogen is concentrated at the interface region with the silicon carbide layer. This localized nitrogen distribution provides effective nitrogen termination at the interface while preventing nitrogen diffusion into the bulk silicon carbide layer, thus avoiding unwanted nitrogen introduction
3Ease of manufacture
If heat treatment is performed to form the silicon oxide film, then the insulating film is formed, but interface state density increases
Solution Approach 1:
The nitrogen-containing silicon oxide film is formed preliminarily before the conventional silicon oxide film. This preliminary formation of the nitrogen-containing layer prepares the interface with proper nitrogen termination and low interface state density before subsequent oxidation processes, preventing interface degradation during heat treatment
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 proposed structure enhances the reliability of the insulating film, improves nitrogen termination, and prevents unwanted nitrogen introduction, thereby achieving desired semiconductor device characteristics.
Implementation Method 1
the first layer and the second layer reduce an interface state density at an interface between the silicon carbide member and the first member
Implementation Method 2
the first layer and the second layer suppress oxidation of the silicon carbide member
Data Source
AI summary
According to one embodiment, a semiconductor device includes a silicon carbide member, a first member, a first layer, and a second layer. The silicon carbide member includes a first region. The first member includes silicon and oxygen. The first layer is provided between the first region and the first member. The first layer includes a bond between silicon and nitrogen. The second layer is provided between the first layer and the first member. The second layer includes a bond between silicon and oxygen and a bond between silicon and nitrogen.