Slit-Anchored MEMS Speaker Membrane for Lower Stress Concentration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing micro sound producing devices, such as MEMS microspeakers, face challenges in achieving high yield rates and performance, particularly in the manufacturing process due to issues with stress concentration and structural integrity of the membrane components.
Innovation Solution
A package structure design incorporating a membrane with specific slit and recess configurations, anchored by an anchor structure, and a forming method that includes patterning a wafer to create trench lines and slits, enhancing the structural integrity and yield rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a continuous membrane structure is used in micro sound producing devices, then the membrane provides good acoustic sealing, but stress concentration occurs leading to reduced yield rate and reliability
Solution Approach 1:
The membrane is divided into multiple membrane subparts (first membrane subpart, second membrane subpart, etc.) separated by slits. This segmentation distributes the stress that would otherwise concentrate in a continuous membrane, preventing stress-related failures and improving yield rate while maintaining acoustic sealing functionality.
Solution Approach 2:
Different regions of the membrane structure are given different properties: membrane subparts have flexible regions for acoustic operation, while anchored edges provide rigid support. The slits create localized stress relief zones without compromising the overall structural integrity or acoustic performance of the device.
2Strength
If the membrane is fully anchored around its perimeter, then structural support is maximized, but acoustic performance and stress distribution are compromised
Solution Approach 1:
The membrane is segmented into multiple subparts with selective anchoring. Each membrane subpart has at least one anchored edge for support and at least one non-anchored edge for acoustic freedom. This allows the membrane to maintain structural support where needed while preserving acoustic performance in other regions.
Solution Approach 2:
Different edges of the membrane subparts have different anchoring conditions: some edges are anchored to provide local structural support, while other edges remain non-anchored to allow acoustic vibration. This localized differentiation of support conditions optimizes both strength and performance.
3Productivity
If traditional manufacturing processes are used without slit patterns, then manufacturing is simpler, but stress concentration reduces yield rate
Solution Approach 1:
The manufacturing process incorporates slit formation steps that divide the membrane into multiple subparts. While this adds manufacturing steps, it eliminates stress concentration issues that would cause higher failure rates, ultimately improving yield rate by preventing stress-related defects during and after manufacturing.
Data Source
AI summary
A forming method of a package structure includes: performing a manufacturing method to manufacture a cell; and disposing the cell within a cover. The manufacturing method of the cell includes: providing a wafer including a first layer and a second layer; and patterning the first layer to form a trench line. A membrane of the first layer includes a first membrane subpart and a second membrane subpart opposite to each other, and a slit penetrates through the membrane because of the trench line. The first membrane subpart includes a first anchored edge which is fully or partially anchored by an anchor structure, the second membrane subpart includes a second anchored edge which is fully or partially anchored by the anchor structure, and edges of the first membrane subpart other than the first anchored edge and edges of the second membrane subpart other than the second anchored edge are non-anchored.