Microphone Package Acoustic Channel Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing microphone packages require an airtight seal between the microphone and the substrate, which often leads to soldering issues that can damage the fragile MEMS microstructure and reduce device reliability and yield.
Innovation Solution
The solution eliminates the need for a sealing ring by forming a direct acoustic channel from the device housing to the microphone package, using a filter that extends through the printed circuit board to create an unsealed path, thereby avoiding soldering near the microphone aperture and reducing vibration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an airtight seal is used between the microphone package and substrate, then environmental protection of the MEMS die is improved, but soldering issues occur that damage the MEMS microstructure and reduce device reliability
Solution Approach 1:
The patent removes the sealing ring component entirely from the microphone package design. Instead of using a separate sealing ring that requires soldering, the package uses the substrate itself as the sealing surface, eliminating the need for additional sealing components and their associated soldering operations.
Solution Approach 2:
The patent combines the sealing function with the substrate by creating direct contact between the package base and substrate surfaces. The sealing interface is integrated into the substrate structure itself, merging the mechanical support and sealing functions into a single integrated solution rather than using separate components.
2Reliability
If a sealing ring is used to create an airtight seal, then environmental protection is improved, but device complexity increases due to extra components and soldering requirements
Solution Approach 1:
The sealing ring component is completely extracted from the design. The patent achieves sealing through direct surface contact between the package base and substrate, eliminating the need for separate sealing components and simplifying the overall package structure.
Solution Approach 2:
The substrate serves multiple functions simultaneously: it provides mechanical support, electrical connections, and the sealing surface. This multi-functionality eliminates the need for dedicated sealing components, reducing device complexity while maintaining seal integrity.
3Reliability
If soldering is performed near the microphone aperture, then sealing is achieved, but vibration is increased and the fragile MEMS microstructure is damaged
Solution Approach 1:
The patent removes the soldering operation from the sealing process near the microphone aperture. By using direct surface contact sealing between the package base and substrate, the design eliminates the need for soldering in the vicinity of the sensitive MEMS structure, thereby avoiding vibration-induced damage.
Solution Approach 2:
The substrate acts as an intermediary that provides both mechanical support and sealing without requiring soldering near the aperture. The sealing is achieved through controlled contact between the package base and substrate surfaces, using the substrate as a mediator that eliminates the harmful soldering process from the critical area.
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 simplifies fabrication, improves device reliability, and reduces costs by eliminating the need for extra components and soldering, while maintaining effective sound transmission.
Implementation Method 1
The filter forms an acoustic channel between the housing aperture and the package aperture
Data Source
AI summary
An apparatus has a packaged microphone with a base and a lid that at least in part form an interior chamber containing a microphone die. The base has a bottom surface with an electrical interface and a base aperture. The apparatus also has a device housing having an internal surface, and a filter extending between the internal surface of the device housing, through an underlying substrate, and the bottom surface of the base.