Composite Dielectric Layer for Etch Selectivity and Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The semiconductor industry faces challenges in scaling down semiconductor devices while maintaining high performance and low costs, leading to increased complexity in processing and manufacturing due to the need for high storage capacity and fast processing systems.
Innovation Solution
The development of a composite dielectric layer formed through alternately stacking silicon-containing dielectric layers with varying compositions of Si, C, O, and N, achieved by tuning precursor materials, deposition cycles, and plasma treatments, which enhances mechanical and chemical properties such as Young's modulus and etching selectivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If semiconductor devices are scaled down to increase packing density and storage capacity, then device integration and storage capacity are improved, but processing and manufacturing complexity increases
Solution Approach 1:
The dielectric layer is segmented into multiple sub-layers with different compositions (first dielectric layer with higher nitrogen content, second dielectric layer with higher carbon content). This segmentation allows each sub-layer to provide specific functions independently, managing the complexity of scaled-down devices through modular structure design.
Solution Approach 2:
The patent employs composite dielectric materials with varying Si, C, O, and N compositions in different layers. This composite approach enables optimization of mechanical and chemical properties for specific processing requirements, addressing the manufacturing complexity challenge by providing tailored material properties for scaled-down device fabrication.
2Length of moving object
If dielectric layers are made thinner to accommodate scaled-down devices, then device dimension is reduced, but mechanical strength and processing control become more difficult to maintain
Solution Approach 1:
Different regions of the dielectric layer structure are assigned different compositions and properties. The first dielectric layer has higher nitrogen content for specific mechanical properties, while the second dielectric layer has higher carbon content for different mechanical characteristics. This local quality differentiation maintains overall mechanical strength even as the total thickness is reduced for scaled-down devices.
Solution Approach 2:
The composite dielectric structure combines materials with different compositions to achieve the required mechanical strength at reduced thickness. The synergistic combination of nitrogen-rich and carbon-rich layers provides enhanced mechanical properties that would not be achievable with a single uniform material at the same reduced thickness.
3Device complexity
If single-layer dielectric structures are used to simplify manufacturing, then device complexity is reduced, but etching selectivity and processing control are insufficient
Solution Approach 1:
The dielectric layer is divided into multiple segments (first and second dielectric layers) with distinct compositions. This segmentation provides different etching rates and selectivities for each layer, enabling precise processing control during fabrication. The segmented structure allows selective etching operations to target specific layers, improving manufacturing precision despite increased structural complexity.
Solution Approach 2:
The patent varies compositional parameters (Si, C, O, N content) between different dielectric layers to achieve desired etching selectivity. By changing the chemical composition parameters of each layer, the etching behavior can be precisely controlled, allowing different layers to be etched at different rates or with different selectivities to underlying structures.
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 composite dielectric layer improves mechanical strength and chemical selectivity, enabling better processing control and integration in semiconductor structures, thereby addressing the complexity and performance demands of scaled-down semiconductor devices.
Implementation Method 1
a dielectric layer formed over the substrate and the gate structure
Implementation Method 2
formed by a physical vapor deposition (PVD) process
Implementation Method 3
formed by a chemical vapor deposition (CVD) process
Data Source
AI summary
A device includes a first dielectric layer, a first conductor, an etch stop layer, a second dielectric layer, and a second conductor. The first conductor is in the first dielectric layer. The etch stop layer is over the first dielectric layer. The etch stop layer has a first surface facing the first dielectric layer and a second surface facing away from the first dielectric layer, and a concentration of carbon in the etch stop layer periodically varies from the first surface to the second surface. The second dielectric layer is over the etch stop layer. The second conductor is in the second dielectric layer and the etch stop layer and electrically connected to the first conductor.