MEMS Cap Segmentation for Electrical Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing MEMS components lack integrated electrical functionality within the cap, which limits their ability to provide independent electrical functions and protect the micromechanical structure effectively while maintaining hermetic sealing.
Innovation Solution
The cap is designed with electrically insulated sections extending over its entire thickness, allowing for independent electrical contacting and integration of multiple functions, including complex circuit functions, achieved through standard semiconductor processing methods such as trench structuring and rear-side thinning with insulating materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the cap is designed as a hermetically sealed protective structure, then the micromechanical structure is protected from environmental influences, but the cap cannot provide independent electrical functions
Solution Approach 1:
The cap is divided into multiple electrically insulated sections that extend over the entire thickness of the cap. These sections are electrically decoupled from each other through insulation structures, allowing each section to serve independent electrical functions while the cap collectively maintains hermetic sealing protection
Solution Approach 2:
The cap is designed to simultaneously perform multiple functions: hermetic sealing protection of the micromechanical structure and provision of independent electrical functions through its electrically insulated sections. Each insulated section can be independently contacted and configured for different electrical purposes
2Ease of manufacture
If the cap is made as a single integrated structure, then manufacturing is simplified, but independent electrical contacting of different cap regions is not possible
Solution Approach 1:
The cap incorporates electrically insulated sections that segment the cap into electrically independent regions. These sections are created using standard semiconductor processing methods, including trench structures filled with insulating material, which are integrated into the cap manufacturing process
Solution Approach 2:
Electrically insulating material is introduced as an intermediary substance within trench structures in the cap. This insulating material electrically decouples adjacent sections of the cap while being integrated into the overall cap structure, enabling independent electrical contacting without compromising the hermetic seal
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 design enables the integration of independent electrical functions within the cap, enhancing the component's sensitivity and stability by allowing for differential capacitor systems with three electrode layers, reducing interference from bending and vibration, and providing mechanical overload protection.
Implementation Method 1
the cap includes at least one section extending over the entire thickness of the cap, which is electrically insulated from the adjoining semiconductor materials in such a way that it may be electrically contacted independently from the remaining sections of the cap
Implementation Method 2
the component described in US Patent Application Publication No. 2011/0049652 A1 is equipped with a capacitor system, which—depending on the MEMS function—may be used for detecting externally caused deflections of the structural element
Implementation Method 3
the capacitor system includes at least one deflectable electrode on the deflectable structural element of the MEMS element and stationary electrodes, which are implemented here in a structured metal layer on the surface of the ASIC substrate
Data Source
AI summary
A component has at least one MEMS element and at least one cap made of a semiconductor material. The cap, in addition to its mechanical function as a terminus of a cavity and protection of the micromechanical structure, is provided with an electrical functionality. The micromechanical structure of the MEMS element of the component is situated in a cavity between a carrier and the cap, and includes at least one structural element which is deflectable out of the component plane within the cavity. The cap includes at least one section extending over the entire thickness of the cap, which is electrically insulated from the adjoining semiconductor material in such a way that it may be electrically contacted independently from the remaining sections of the cap.