Wafer Edge Sidewall Barrier Using High-Density Protection Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wafer bonding processes face challenges in preventing detrimental chemicals and moisture from penetrating through the sidewalls, leading to degradation of low-k dielectric layers and metal features in device wafers.
Innovation Solution
A high-density sidewall protection layer is formed using materials like silicon nitride or metal compounds, which are denser than silicon oxide, to block the penetration of chemicals and moisture, thereby protecting the device wafer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a standard silicon oxide sidewall protection layer is used, then the manufacturing process is simple and cost-effective, but the layer cannot effectively block detrimental chemicals and moisture from penetrating through, leading to degradation of low-k dielectric layers and metal features
Solution Approach 1:
The patent applies composite materials by combining silicon oxide with high-density materials (such as silicon nitride, tungsten oxide, or hafnium oxide) to form a multi-layer sidewall protection structure. This composite approach leverages the benefits of both materials: silicon oxide provides good adhesion and basic protection, while the high-density material layer provides superior blocking capability against moisture and chemicals. The resulting composite structure achieves enhanced reliability without excessive complexity, as the additional layer can be integrated into existing manufacturing processes.
Solution Approach 2:
The patent applies parameter changes by modifying the density parameter of the sidewall protection layer material. Instead of using standard silicon oxide with lower density, the invention introduces high-density materials (with density significantly higher than silicon oxide) to form the protection layer. This parameter change directly addresses the penetration issue by creating a more impervious barrier while maintaining compatibility with standard fabrication processes through controlled deposition techniques.
2Object-affected harmful factors
If a high-density material sidewall protection layer is formed, then the blocking ability against chemicals and moisture is significantly improved, but the manufacturing process complexity and deposition requirements increase
Solution Approach 1:
The patent applies segmentation by dividing the sidewall protection function into multiple distinct layers: a silicon oxide layer and a separate high-density material layer. This segmentation allows each layer to be optimized for its specific function (adhesion/protection vs. blocking) and enables the use of different deposition parameters and materials for each layer. The segmented structure makes the manufacturing process more manageable by breaking down the complex requirement of creating a single perfect barrier into two simpler, specialized layers that can be deposited using standard equipment and processes.
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 high-density sidewall protection layer effectively prevents degradation of low-k dielectric layers and metal features by blocking moisture and chemicals, enhancing the integrity of the device wafer.
Implementation Method 1
A high-density sidewall protection layer is formed using materials like silicon nitride or metal compounds, which are denser than silicon oxide, to block the penetration of chemicals and moisture
Data Source
AI summary
A method includes bonding a first wafer to a second wafer, performing a trimming process on the first wafer, and depositing a sidewall protection layer contacting a sidewall of the first wafer. The depositing the sidewall protection layer includes depositing a high-density material in contact with the sidewall of the first wafer. The sidewall protection layer has a density higher than a density of silicon oxide. The method further includes removing a horizontal portion of the sidewall protection layer that overlaps the first wafer, and forming an interconnect structure over the first wafer. The interconnect structure is electrically connected to integrated circuit devices in the first wafer.