L-Shaped MEMS Package Vibration Immunity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vertical mount MEMS packages are susceptible to vibration, package tilt, and have limitations in EMI shielding, stress isolation, solder joint reliability, and cost, making them unsuitable for applications requiring robustness and reliability, especially in automotive systems like vehicle stability control.
Innovation Solution
A vertical mount MEMS package design featuring an L-shaped substrate with a vertical and horizontal portion, including a mounting region, bond pads, interconnects, and leads, which provides a low profile, vibration immunity, and EMI shielding, while allowing for easy inspection of solder joints, using materials like polymeric or ceramic substrates for improved reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing vertical mount MEMS packages are used, then the MEMS device can be mounted vertically, but the package is susceptible to vibration and package tilt
Solution Approach 1:
The substrate is divided into two distinct portions: a vertical portion for mounting the MEMS die and a horizontal portion for providing stability and vibration immunity. This segmentation allows each portion to be optimized for its specific function, with the horizontal portion acting as a stable base that resists vibration and tilt while the vertical portion provides the necessary mounting surface.
Solution Approach 2:
The substrate transitions from a traditional planar structure to a three-dimensional L-shaped structure with both vertical and horizontal portions. This dimensional change allows the package to achieve vibration immunity and stability while maintaining vertical mounting capability, as the horizontal portion provides a stable base that counteracts vibrational forces.
2Reliability
If existing MEMS packages are used, then electrical connection can be established, but EMI shielding is limited
Solution Approach 1:
The substrate is constructed from materials with complementary properties that provide both mechanical support and electromagnetic interference shielding. The combination of materials in the L-shaped substrate creates a composite structure that simultaneously achieves electrical connectivity, mechanical stability, and EMI shielding capabilities.
3Reliability
If existing MEMS packages are used, then the device can be packaged, but solder joint reliability is compromised
Solution Approach 1:
The substrate design segments the mounting functions, with the horizontal portion providing a stable, vibration-resistant base for solder joints and the vertical portion providing the MEMS die mounting surface. This segmentation isolates the solder joints from vibrational stresses, improving their reliability.
4Reliability
If existing MEMS packages are used, then standard packaging can be implemented, but cost increases
Solution Approach 1:
The L-shaped substrate performs multiple functions simultaneously: it provides mechanical support, vibration immunity, EMI shielding, and electrical connectivity. By integrating these functions into a single substrate structure, the design reduces the need for additional components and assembly steps, thereby lowering manufacturing costs while improving reliability.
Data Source
AI summary
A MEMS package includes a substrate having an L-shaped cross-section. The substrate includes a vertical portion having a front surface and a back surface, and a horizontal portion protruding from a lower part of the front surface of the vertical portion, wherein the front surface of the vertical portion includes a mounting region. A MEMS die is mounted on the mounting region such that the MEMS die is oriented substantially parallel to the front surface; a lid attached to the front surface of the substrate while covering the MEMS die; and a plurality of leads formed on a bottom surface of the substrate. The leads can extend substantially parallel to one another, and substantially perpendicular to the front surface. The MEMS die can be oriented substantially perpendicular to a PCB substrate on which the package is mounted.