Oxygen-Doped Silicon Carbide Seal for Semiconductor Air Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The semiconductor industry faces challenges in forming reliable air gaps in semiconductor devices due to low conformity and etch resistance of existing seal materials, leading to defects such as collapse, chemical solution trapping, physical breakdowns, and electrical shorts, which result in low device yield and failure.
Innovation Solution
A highly rigid silicon carbide layer doped with oxygen (HRSCO) is used as a seal material, which can be deposited and treated to enhance etch resistance and conformity, forming a bilayer seal structure to enclose air gaps and serve as a contact etch stop layer and self-aligned contact, improving mechanical support and chemical resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing seal materials are used to form air gaps, then the air gap structure can be created, but the seal materials exhibit low conformity and low etch resistance leading to collapse, chemical solution trapping, physical breakdowns, and electrical shorts
Solution Approach 1:
The patent employs a bilayer seal structure comprising a first seal material layer (e.g., silicon nitride) and a second seal material layer (e.g., silicon oxide or low-k dielectric material). This composite structure combines the high etch resistance of silicon nitride with the low dielectric constant of the second material, achieving both manufacturing precision and reliability. The first layer provides structural integrity and etch resistance, while the second layer maintains air gap conformity and electrical performance.
2Reliability
If existing seal materials are used to form air gaps, then the air gap structure can be created, but the seal materials exhibit low etch resistance leading to physical breakdowns and electrical shorts
Solution Approach 1:
The bilayer seal structure uses silicon nitride as the first seal material layer, which provides exceptional etch resistance to prevent physical breakdowns during fabrication processes. The second layer uses materials with low dielectric constants to maintain electrical performance. This composite approach ensures both air gap integrity and sufficient etch resistance against chemical solutions.
3Productivity
If seal material is deposited to enclose air gaps, then air gaps are formed, but low conformity leads to defects and low device yield
Solution Approach 1:
The seal structure is segmented into multiple layers with different materials optimized for specific functions. The first layer (silicon nitride) provides structural support and etch resistance, while the second layer (low-k dielectric or silicon oxide) ensures conformal coverage and low parasitic capacitance. This segmentation allows each layer to be optimized independently, improving overall conformity and device yield.
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 HRSCO seal material significantly reduces damage to air gaps, enhances device performance by lowering parasitic capacitance, and increases yield by preventing defects like electrical shorts and chemical contamination, while providing improved etch resistance and conformity.
Implementation Method 1
A highly rigid silicon carbide layer doped with oxygen (HRSCO) is used as a seal material, which can be deposited and treated to enhance etch resistance and conformity
Data Source
AI summary
The present disclosure relates to a semiconductor device including first and second terminals formed on a fin region and a seal layer formed between the first and second terminals. The seal layer includes a silicon carbide material doped with oxygen. The semiconductor device also includes an air gap surrounded by the seal layer, the fin region, and the first and second terminals.