Gradient Cross-Linked Casting Compound for Electronic Components
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current casting compounds for electronic components face challenges in balancing mechanical protection and stress reduction, with rigid compounds providing good protection but causing mechanical stresses due to thermal expansion differences, while soft compounds offer inadequate protection and are prone to chemical penetration.
Innovation Solution
A curable compound with a cross-linking component that can form two different cross-linked systems, one with higher and one with lower cross-link density, allowing for localized curing to create a soft contact region and a rigid protective layer, eliminating the need for an external housing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If rigid casting compounds are used, then mechanical protection and chemical resistance are improved, but mechanical stresses on electronic components increase due to thermal expansion differences and shrinkage
Solution Approach 1:
The patent applies local quality by creating a casting compound with spatially varying cross-link density. The region adjacent to electronic components has lower cross-link density to reduce mechanical stress and accommodate thermal expansion, while distant regions have higher cross-link density to provide mechanical protection and chemical resistance. This gradient structure allows different parts of the same casting compound to have different mechanical properties tailored to their specific functions.
2Stress or pressure
If soft casting compounds are used, then mechanical stresses are reduced, but mechanical protection and chemical resistance deteriorate
Solution Approach 1:
The patent resolves this contradiction by implementing local quality with a cross-link density gradient. The soft, low cross-link density region near components provides stress reduction, while the hard, high cross-link density region at the exterior provides mechanical protection and chemical resistance. This eliminates the need to choose between soft and hard casting compounds.
3Object-affected harmful factors
If a separate housing is added to protect against chemical loads, then chemical resistance is improved, but device complexity and production costs increase
Solution Approach 1:
The patent merges the protective housing function with the casting compound itself. By creating a gradient cross-linked structure where the exterior region has high cross-link density, the casting compound simultaneously provides both the encapsulation function and the chemical/mechanical protection function that would otherwise require a separate housing. This eliminates additional components and simplifies the overall device structure.
4Strength
If multiple casting compounds are used in layers, then both protection and stress reduction are achieved, but manufacturing precision and quality assurance become more difficult
Solution Approach 1:
The patent creates a composite material system within a single casting compound by incorporating multiple functional components: a base polymer matrix, cross-linking agents that create the gradient structure, and potentially fillers. This single composite material provides both the soft inner region for stress reduction and the hard outer region for protection, eliminating the need for multiple separate casting layers and the quality assurance challenges associated with bonding interfaces.
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 approach reduces mechanical stresses on electronic components, enhances protection, and allows for compact design without external housings, achieving reliable and durable electronic components with improved integration density.
Implementation Method 1
the at least one cross-linking component A is photo-cross-linked in at least one first region (i) spaced from the electronic component or the electronic component group
Implementation Method 2
cured to the second cross-linked system at least in a second region (ii) enclosing and immediately surrounding the electronic component or the electronic component group
Data Source
AI summary
The present invention relates to a method for casting electronic components. The invention also relates to a curable compound that can be used as casting compound in the method. The casting compound contains at least one cross-linking component which is homogeneously distributed in the casting compound and can cross-link to at least two different cross-linked systems. A first of these networks has a higher cross-link density than a second cross-linked system, wherein the cross-linking to the first cross-linked system is triggered via an event other than the cross-linking to the second cross-linked system. During casting, the at least one cross-linking component of the casting compound is cured at least in part to the first cross-linked system in at least one first region spaced from the components and at least to the second cross-linked system in a second region enclosing and immediately surrounding the components.