MEMS Packaging With Differential Internal Pressures

Solution Overview

Problem

Current MEMS device packaging technologies face challenges in efficiently managing and controlling internal pressures for diverse MEMS functional structures within a single packaged device, limiting the integration of multiple sensors with varying pressure requirements and increasing chip size and process complexity.

Innovation Solution

The method involves wafer level packaging with a novel process flow that includes forming MEMS functional structures with different internal pressures by using a combination of substrate bonding, etching, and sealing techniques, allowing for the integration of multiple MEMS devices with distinct pressure levels in a single package, utilizing a sealing material to maintain pressure and an encapsulation material for protection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple MEMS devices with different internal pressures are packaged separately, then each device can have its required pressure, but the chip size, number of process steps, and manufacturing costs increase

Engineering Contradiction:

Improvepressure controlVSAvoidpackaging complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines multiple MEMS devices with different internal pressure requirements into a single integrated package. The package includes a substrate with multiple MEMS devices, where each device has its own sealed cavity but they share common packaging infrastructure. This merging approach maintains the required pressure differential for each device while reducing overall packaging complexity, chip size, and manufacturing costs compared to separate packaging of each device.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If multiple MEMS devices with different internal pressures are packaged separately, then each device can have its required pressure, but the manufacturing costs increase

Engineering Contradiction:

Improvepressure controlVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent combines multiple MEMS devices with different internal pressure requirements into a single integrated package. The package includes a substrate with multiple MEMS devices, where each device has its own sealed cavity but they share common packaging infrastructure. This merging approach maintains the required pressure differential for each device while reducing overall packaging complexity, chip size, and manufacturing costs compared to separate packaging of each device.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If traditional packaging methods are used without wafer level packaging, then device functionality is maintained, but the wiring pitch and connection complexity increase

Engineering Contradiction:

Improvedevice functionalityVSAvoidwiring complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs wafer level packaging with a redistribution layer that fans out wiring in a different spatial dimension. Instead of direct vertical connections requiring small pitch, the redistribution layer routes signals laterally across the substrate, increasing the effective wiring pitch and reducing connection complexity while maintaining device functionality.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS9359194B2MEMS devices, packaged MEMS devices, and methods of manufacture thereof

Publication Date: 2016.06.07 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

MEMS devices, packaged MEMS devices, and methods of manufacture thereof are disclosed. In one embodiment, a microelectromechanical system (MEMS) device includes a first MEMS functional structure and a second MEMS functional structure. An interior region of the second MEMS functional structure has a pressure that is different than a pressure of an interior region of the first MEMS functional structure.