Sputtered EMI Shield for Electro-Optic Die Packages
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Communication network devices face challenges in managing high data demands due to Electro-Magnetic Interference (EMI), which affects their performance and requires packaging that complies with EMI requirements while conserving space and reducing thermal junction temperatures.
Innovation Solution
A die package featuring a sputtered metal shield that is in direct physical and thermal contact with the die, providing electrical grounding and comprising copper with a stainless steel coating, to reduce EMI and enhance thermal communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a traditional EMI shield is used, then EMI protection is provided, but package footprint and space are increased
Solution Approach 1:
The patent applies a thin film sputtered metal shield (copper or aluminum) deposited directly onto the molding compound surface. This thin film approach provides effective EMI shielding while maintaining a compact package footprint, avoiding the need for bulky traditional EMI shields that would increase package area.
Solution Approach 2:
The EMI shield function is merged with the existing molding compound structure by depositing the metal shield directly onto it. This integration combines the structural molding compound with the EMI shielding function in a single unified component, eliminating the need for separate EMI shield elements and reducing overall package footprint.
2Object-affected harmful factors
If EMI shielding is added, then EMI protection is improved, but device complexity increases
Solution Approach 1:
The EMI shield is merged into the molding compound assembly through direct deposition, creating a single integrated structure rather than adding separate components. This reduces device complexity by eliminating the need for additional EMI shield parts, fasteners, and assembly steps.
Solution Approach 2:
The molding compound serves multiple functions: structural support, mechanical protection, and EMI shielding (when coated with metal). This multi-functionality reduces overall device complexity by having one component perform multiple roles rather than requiring separate dedicated elements for each function.
3Object-affected harmful factors
If a thick EMI shield is used, then EMI protection is enhanced, but thermal communication with the die is reduced
Solution Approach 1:
A thin film metal shield is deposited onto the molding compound, providing sufficient EMI protection while maintaining thermal transparency. The thinness of the film allows heat to conduct through it effectively, preventing excessive junction temperature buildup while still achieving the required EMI shielding performance.
Solution Approach 2:
The shield thickness parameter is optimized to be thin rather than thick, changing the dimensional parameter to simultaneously achieve both EMI protection and thermal communication. This parameter optimization allows the shield to be transparent to heat conduction while maintaining electromagnetic shielding effectiveness.
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 achieves a significant reduction in EMI by up to 15 dB, conserves space, and improves thermal performance, making it suitable for high-bandwidth applications like social networks processing large multimedia data.
Implementation Method 1
a sputtered metal shield to reduce Electro-Magnetic Interference (EMI)
Implementation Method 2
the die and the MUF are subjected to metal sputtering
Implementation Method 3
Direct physical contact between the shield and the die surface exposed by the MUF, enhances thermal communication
Data Source
AI summary
Embodiments relate to a die package featuring a sputtered metal shield to reduce Electro-Magnetic Interference (EMI). According to a particular embodiment, a die featuring a top surface exposed by surrounding Molded Underfill (MUF) material, is subjected to metal sputtering. The resulting sputtered metal shield is in direct physical and thermal contact with the die, and is in electrical contact with a substrate supporting the die (e.g., to provide shield grounding). Specific embodiments may be particularly suited to reducing the EMI of a package containing an electro-optic die, to between 3-15 dB. The conformal nature and small thickness of the sputtered metal shield desirably conserves space and reduces package footprint. Direct physical contact between the shield and the die surface exposed by the MUF, enhances thermal communication (e.g., reducing junction temperature). According to certain embodiments, the sputtered metal shield comprises a stainless steel liner, copper, and a stainless steel coating.