Patterned Adhesive Layer for IC Package Warpage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing adhesive layer in integrated circuit packaging causes warpage and distortion in IC packages due to uneven stress distribution and makes precise alignment of closely spaced dies difficult, leading to issues like die movement and attraction during curing.
Innovation Solution
Applying a patterned adhesive layer directly to the active surface of the semiconductor die and corresponding die locations on the dielectric substrate, with a gap between die locations free of adhesive, to minimize stress and improve alignment precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a continuous adhesive layer is applied across the entire dielectric substrate surface, then the dies are securely bonded to the substrate, but the IC package experiences warpage and distortion due to uneven stress distribution
Solution Approach 1:
The continuous adhesive layer is segmented into discrete adhesive islands or regions. Each adhesive region is positioned only where needed to bond specific dies to the substrate, rather than covering the entire substrate surface. This segmentation reduces the total adhesive volume and creates more uniform stress distribution, thereby minimizing warpage and distortion while maintaining secure bonding.
Solution Approach 2:
The adhesive is applied with local quality by positioning it only in specific regions where bonding is required, rather than uniformly across the entire substrate. This localized adhesive application matches the stress distribution to the actual bonding needs, reducing unnecessary stress in adhesive-free regions and preventing package distortion.
2Stability of the object's composition
If the adhesive layer is applied to cover the entire dielectric substrate, then die positioning is stable, but closely spaced dies cannot be precisely aligned due to die swimming and attraction during curing
Solution Approach 1:
The adhesive layer is segmented into separate adhesive regions for each die location, with gaps between them. This prevents the formation of a continuous adhesive film that would allow dies to swim or attract each other. Each die is bonded independently to its own adhesive region, enabling precise alignment and positioning without interference from adjacent dies.
Solution Approach 2:
The harmful continuous adhesive film is extracted and replaced with discrete adhesive regions. By removing the adhesive from the spaces between dies, the patent eliminates the mechanism that causes die swimming and attraction, while retaining the bonding function where needed.
3Ease of manufacture
If a standard adhesive application process is used, then the manufacturing process is simple, but processing time increases and material costs rise due to excessive adhesive usage
Solution Approach 1:
Instead of applying adhesive to the entire substrate surface (excessive action), the patent applies adhesive only to the necessary regions (partial action). This reduces the total amount of adhesive material required, decreases processing time for adhesive application and curing, and lowers material costs while maintaining effective bonding.
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 warpage and distortion, allows for closer die spacing, and simplifies the assembly process while reducing material costs and processing time.
Implementation Method 1
a first adhesive layer having a first surface coupled to the active surface of the first die and a second surface opposite the first surface
Data Source
AI summary
A chip package includes a first die with an active surface having at least one die pad positioned thereon; a first adhesive layer having a first surface coupled to the active surface of the first die and a second surface opposite the first surface; and a first dielectric layer having a top surface. A first portion of the top surface of the first dielectric layer is coupled to the second surface of the first adhesive layer. A second portion of the top surface of the first dielectric layer, distinct from the first portion, is substantially free of adhesive.