Substrate Anchor Structure for Thermal Stress Relief
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Connections between structures are typically unreliable due to lack of additional support, leading to potential failure.
Innovation Solution
A substrate anchor structure is created using a first substrate with a dielectric layer and a solder structure, where an underfill layer comprising a silica-epoxy composite adhesive material is formed over the dielectric layer, providing additional support by encapsulating the solder structure and reducing stress caused by thermal cycling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If connections between structures are made without additional support means, then the device complexity is reduced, but the reliability of the connection deteriorates
Solution Approach 1:
The connection structure is divided into multiple functional segments: a solder joint providing electrical connection, an underfill layer providing mechanical support and stress distribution, and optional anchor features providing additional mechanical attachment. This segmentation allows each component to specialize in a specific function, improving overall connection reliability without creating a monolithic complex structure.
Solution Approach 2:
The connection is extended from a simple planar interface to a three-dimensional structure by adding vertical elements such as underfill material filling the space between substrates and anchor features extending into recesses. This dimensional expansion provides additional support pathways and stress distribution mechanisms that enhance reliability.
2Reliability
If additional support means are added to connections, then the reliability improves, but the device complexity increases
Solution Approach 1:
Multiple functions are merged into integrated structures: the underfill layer simultaneously provides mechanical support, stress distribution, and gap filling; anchor features combine mechanical attachment with electrical connection pathways; dielectric layers integrate structural support with electrical insulation. This merging reduces the number of separate components needed while achieving multiple objectives.
Solution Approach 2:
Key components are designed to perform multiple functions: the underfill layer provides both mechanical support and stress relief; the solder joint provides both electrical connection and mechanical bonding; anchor features provide both structural attachment and alignment references. This multi-functionality reduces the need for additional specialized components.
3Stability of the object's composition
If an underfill layer is formed over the solder structure, then the stress distribution improves, but the manufacturing process complexity increases
Solution Approach 1:
The underfill layer is applied in advance of final assembly, allowing it to pre-position support structures and define alignment features before substrates are permanently bonded. This preliminary action simplifies subsequent assembly steps and ensures proper stress distribution from the outset.
Solution Approach 2:
The underfill material is formulated to self-level and self-align during application, automatically filling gaps and conforming to underlying structures without requiring complex positioning equipment or multiple adjustment steps. This self-service capability reduces manufacturing complexity while ensuring proper stress distribution.
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 solution provides a reliable means of support for connections between structures, enhancing their stability and reducing the risk of failure by distributing thermal stresses effectively.
Implementation Method 1
an underfill layer comprising a silica-epoxy composite adhesive material, wherein said underfill layer is formed over said top surface of said first dielectric layer and over said first solder structure
Data Source
AI summary
An electrical structure and method of forming. The electrical structure includes a first substrate, a first dielectric layer, an underfill layer, a first solder structure, and a second substrate. The first dielectric layer is formed over a top surface of the first substrate. The first dielectric layer includes a first opening extending through a top surface and a bottom surface of said first dielectric layer. The first solder structure is formed within the first opening and over a portion of the top surface of said first dielectric layer. The second substrate is formed over and in contact with the underfill layer.