Multi-Die Package Layout With Non-Active Dies for Stress Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multi-die packages experience stress and strain due to coefficient of thermal expansion (CTE) mismatch between IC dies and encapsulant/underfill materials, leading to warpage, bending, and cracking, which can result in physical damage and failure.
Innovation Solution
Incorporating non-active dies among the IC dies to reduce the amount of encapsulant/underfill material, thereby minimizing CTE mismatch, and positioning multiple non-active dies between active IC dies to increase gap areas for stress absorption, ensuring more even distribution of stresses and strains.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If more encapsulant/underfill material is used to fill gaps between IC dies, then the gaps are fully filled and structural integrity is improved, but the CTE mismatch increases leading to more stress and strain
Solution Approach 1:
The patent extracts or removes the harmful encapsulant/underfill material from certain gap regions by introducing non-active dies to occupy those spaces, thereby eliminating the source of CTE mismatch stress while maintaining structural integrity through the presence of the dies themselves
Solution Approach 2:
The patent changes the material composition parameter in the gaps from encapsulant/underfill material to non-active dies, fundamentally altering the CTE characteristics of the gap-filling elements to match the active IC dies and reduce thermal expansion mismatch stress
2Stress or pressure
If non-active dies are positioned between active IC dies, then gap areas for stress absorption increase and stress distribution improves, but the device complexity increases
Solution Approach 1:
The non-active dies serve multiple functions: they act as stress absorption gaps, provide structural support, enable thermal management pathways, and facilitate electrical redistribution, thereby managing stress distribution without proportionally increasing device complexity
Solution Approach 2:
The non-active dies function as intermediary elements between active IC dies, mediating the stress and thermal effects between adjacent active components while providing a controlled interface for stress management and signal redistribution
3Stress or pressure
If non-active dies are incorporated to reduce encapsulant material, then CTE mismatch is minimized and stress is reduced, but the manufacturing process becomes more complex
Solution Approach 1:
The patent merges the non-active dies with the active IC dies in a single package substrate, combining their attachment processes and utilizing shared interposer infrastructure, thereby reducing the overall manufacturing complexity despite the additional component type
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 the likelihood of warpage, bending, and cracking in the multi-die package, enhancing its yield by distributing thermal stresses more evenly and minimizing the risk of physical damage to the package and its dies.
Implementation Method 1
Multi-die packages experience stress and strain due to coefficient of thermal expansion (CTE) mismatch between IC dies and encapsulant/underfill materials
Data Source
AI summary
A multi-die package includes a plurality of non-active dies among the IC dies included in the multi-die package. The non-active dies may be included to reduce the amount of encapsulant material and/or an underfill material that is used in the multi-die package, which reduces the amount of CTE mismatch in the multi-die package. Moreover, a plurality of non-active dies may be positioned in an adjacent manner between two or more active IC dies. The use of a plurality of non-active dies in a particular area of the multi-die package increases the quantity of gaps in the multi-die package. The increased quantity of gaps in the multi-die package provides an increased amount of area in the multi-die package for stress and strain absorption, and enables more even distribution of stresses and strains in the multi-die package.