Semiconductor Package Layout Using Dummy Dies to Minimize Warpage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of multiple semiconductor devices into compact, high-performance packages poses challenges due to thermal expansion differences during manufacturing, leading to warpage issues that can hinder subsequent processing steps and increase costs.
Innovation Solution
The use of a semiconductor package structure with a central region containing functional dies and a peripheral region filled with dummy dies, where the vacancy ratios of these regions are tuned to control warpage, allowing for reduced deformation and improved manufacturing yield by optimizing the distribution and size of dummy dies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple semiconductor devices are integrated into compact packages, then device density and functionality are improved, but thermal expansion differences cause warpage issues that worsen manufacturing precision
Solution Approach 1:
The patent applies local quality by differentiating the treatment of central and peripheral regions of the wafer. Functional dies are placed in the central region while dummy dies are strategically positioned in the peripheral region. This spatial differentiation allows the peripheral dummy dies to specifically address warpage control needs without interfering with the functional performance of central dies, thus resolving the contradiction between high device integration and manufacturing precision.
Solution Approach 2:
The patent employs parameter changes by adjusting the vacancy ratio (the ratio of empty space to total area) in different regions of the wafer. By optimizing the vacancy ratio in the peripheral region through strategic dummy die placement, the patent modifies the thermal expansion characteristics of the overall structure. This parameter adjustment enables compact package integration while maintaining warpage control within acceptable manufacturing tolerances.
2Manufacturing precision
If dummy dies are added to control warpage, then manufacturing precision is improved, but device complexity and material usage increase
Solution Approach 1:
The patent applies universality by designing dummy dies that serve multiple functions simultaneously. The dummy dies in the peripheral region not only control warpage but also maintain wafer structural integrity, provide thermal management support, and enable more aggressive central region die placement for higher density. This multi-functionality reduces the need for additional separate structures, thereby limiting the increase in overall device complexity.
Solution Approach 2:
The patent uses copying by replicating the dummy die structure in standardized patterns around the peripheral region. Rather than designing complex unique structures for warpage control, simple replicated dummy die units are deployed systematically. This copying approach simplifies the manufacturing process and reduces structural complexity while effectively addressing warpage through cumulative structural support.
3Reliability
If vacancy ratios are optimized to minimize warpage, then manufacturing yield is improved, but the manufacturing process complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-calculating and pre-determining the optimal vacancy ratios and dummy die placements before the actual wafer fabrication process. The vacancy ratio optimization is performed during the design stage, allowing the manufacturing process to proceed with predetermined parameters rather than requiring complex real-time adjustments. This advance planning simplifies the actual manufacturing process while maintaining high yield through optimized structural parameters.
Solution Approach 2:
The patent employs self-service by designing a structure where the dummy dies automatically compensate for thermal expansion effects during the manufacturing process. The peripheral dummy dies inherently provide the necessary structural support and thermal management without requiring active control mechanisms or complex process interventions. This self-compensating design improves yield while minimizing the need for complex process optimization during manufacturing.
Data Source
AI summary
A semiconductor package has central region and peripheral region surrounding central region. The semiconductor package includes dies, encapsulant, and redistribution structure. The dies include functional die and first dummy dies. Functional die is disposed in central region. First dummy dies are disposed in peripheral region. Redistribution structure is disposed on encapsulant over the dies, and is electrically connected to functional die. Vacancy ratio of central region is in the range from 1.01 to 3.00. Vacancy ratio of the peripheral region is in the range from 1.01 to 3.00. Vacancy ratio of central region is a ratio of total area of central region to total area occupied by dies disposed in central region. Vacancy ratio of peripheral region is a ratio of total area of peripheral region to total area occupied by first dummy dies disposed in peripheral region.