Silicon Nitride Film Stabilizes Drain Current in HEMT Transistors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High silicon composition in silicon-rich silicon nitride films used on nitride semiconductor layers leads to drift of drain current in semiconductor devices, particularly in high-frequency applications like HEMT transistors, causing instability and performance degradation.
Innovation Solution
A method involving the formation of a silicon nitride film with a refractive index of 2.2 or higher on a nitride semiconductor layer, incorporating elements like oxygen, nitrogen, fluorine, phosphorus, sulfur, or selenium through plasma exposure, ion implantation, or thermal diffusion, which replaces silicon dangling bonds with stable Si-O bonds, reducing potential energy variations and suppressing drain current collapse.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a high silicon composition ratio is used in the silicon-rich silicon nitride film to suppress drain current collapse, then the drain current collapse is suppressed, but the drain current drift occurs
Solution Approach 1:
The patent changes the chemical composition parameters of the silicon nitride film by introducing oxygen, nitrogen, fluorine, phosphorus, sulfur, or selenium elements. This modifies the film's properties to achieve both drain current collapse suppression and drift reduction simultaneously, resolving the contradiction between reliability and stability
2Reliability
If a silicon-rich silicon nitride film is formed on the nitride semiconductor layer to suppress drain current collapse, then the collapse phenomenon is suppressed, but the drain current drift increases
Solution Approach 1:
The patent creates a composite material structure by incorporating multiple elements (oxygen, nitrogen, fluorine, phosphorus, sulfur, or selenium) into the silicon nitride film. This composite approach allows the film to exhibit both collapse suppression and reduced drift characteristics, resolving the contradiction between reliability and manufacturing precision
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 approach effectively stabilizes the drain current and maintains saturated power levels over continuous energization, enhancing the reliability and performance of semiconductor devices by minimizing the impact of silicon-rich film composition on nitride semiconductor layers.
Implementation Method 1
a process of exposing the silicon nitride film to plasma including the at least one of elements
Implementation Method 2
a process of ion-implanting the at least one of elements into the silicon nitride film
Implementation Method 3
a process of thermally diffusing the at least one of elements into the silicon nitride film
Data Source
AI summary
A method for fabricating a semiconductor device includes: forming a silicon nitride film having a refractive index equal to or larger than 2.2 on a nitride semiconductor layer; and introducing at least one of elements that are oxygen, nitrogen, fluorine, phosphorus, sulfur and selenium into the silicon nitride film, the silicon nitride film including the at least one of elements remaining on the nitride semiconductor layer. The at least one of elements is introduced by a process of exposing the silicon nitride film to plasma including the at least one of elements, a process of ion-implanting the at least one of elements into the silicon nitride film, or a process of thermally diffusing the at least one of elements into the silicon nitride film. The silicon nitride film is formed in contact with a surface of the nitride semiconductor layer.