Semiconductor Device Air-Gap Formation for Uniform Electrical Isolation
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Solution Overview
Problem
The challenge in semiconductor manufacturing is the difficulty in completely removing narrow sacrificial layers to form air spacer layers with uniform surface uniformity, leading to reduced electrical isolation and performance due to non-uniform etching.
Innovation Solution
Expose part of the sacrificial layer to allow direct reaction and removal, replacing traditional etching methods, ensuring complete removal and improved surface uniformity of air gaps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional etching methods are used to remove the sacrificial layer, then the air spacer layer is formed, but the etching is not uniform and the sacrificial layer cannot be completely removed, leading to poor surface uniformity
Solution Approach 1:
The patent replaces the mechanical/chemical etching process with a thermal oxidation process. Instead of using etching agents to remove the sacrificial layer, the method uses oxidation to convert the sacrificial layer into a dielectric layer in-situ, eliminating the uniformity problems associated with etching while maintaining the air spacer structure.
Solution Approach 2:
The patent changes the physical and chemical parameters of the sacrificial layer by subjecting it to oxidation conditions. The sacrificial layer is transformed from a removable material into a stable dielectric layer through controlled oxidation, changing its chemical composition and properties to achieve both complete removal of the original sacrificial material and formation of a uniform insulating layer.
2Productivity
If the spacing between conductive structures is reduced to increase distribution density, then integration level improves, but dielectric breakdown and parasitic capacitance increase
Solution Approach 1:
The patent introduces an air spacer layer as an intermediary between adjacent conductive structures. This air gap acts as a mediator that provides electrical isolation and reduces parasitic capacitance, enabling closer spacing of conductive structures while maintaining reliability. The air spacer serves as a physical and electrical buffer between structures.
Solution Approach 2:
The patent extracts the sacrificial layer material and replaces it with an air spacer layer. By removing the sacrificial layer completely and forming an air gap in its place, the method creates effective electrical isolation between conductive structures, allowing higher distribution density without compromising electrical performance.
3Manufacturing precision
If the width of the air spacer layer is made very small (no more than 5 nm) to achieve precise isolation, then electrical isolation improves, but it becomes hard to completely remove the sacrificial layer by etching
Solution Approach 1:
The patent replaces the etching process with thermal oxidation. Instead of attempting to etch away the sacrificial layer completely (which fails at widths ≤5 nm), the method uses oxidation to transform the sacrificial layer into a dielectric layer in-situ. This substitution eliminates the removal completeness problem while maintaining precise width control.
Solution Approach 2:
The patent converts the presence of the sacrificial layer, which is normally a harmful impurity that must be removed, into a beneficial dielectric layer through oxidation. The sacrificial layer material is transformed from something to be eliminated into a useful insulating component, turning the manufacturing difficulty into an advantage.
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 method enhances electrical isolation and performance by forming uniform air gaps between conductive structures, improving the insulation effect and overall semiconductor device functionality.
Implementation Method 1
expose part of the sacrificial layer to allow direct reaction and removal
Data Source
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AI summary
The present disclosure provides a method for manufacturing a semiconductor device and a semiconductor device. The method for manufacturing a semiconductor device includes: providing a substrate; forming a plurality of first structures extending in a first direction on the substrate; forming a sacrificial layer on sidewalls of the first structures; forming an outer spacer layer on a sidewall of the sacrificial layer; removing part of the outer spacer layer to obtain a patterned outer spacer layer that exposes part of the sacrificial layer; and removing the sacrificial layer to form air gaps between the patterned outer spacer layer and the first structures.