Semiconductor Stress Sensing Cell Matrix for Local Stress Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies struggle to accurately determine the distribution of mechanical stresses in semiconductor materials, which can impact the performance of electronic systems and components, particularly in MEMS gyroscopes, due to the limitations of single stress-sensing structures.
Innovation Solution
A stress sensing device comprising a plurality of stress sensing structures with varied sensing characteristics, including different combinations of sensing types, doping types, and orientations, distributed in a sensing cell matrix on the semiconductor material, which generates electrical signals representing mechanical stress components, and a voltage conversion circuitry to combine these signals for precise stress measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single stress-sensing structure is used, then the device complexity is reduced, but the measurement precision of mechanical stress distribution deteriorates
Solution Approach 1:
The stress sensing structure is divided into multiple discrete stress sensing structures arranged in a matrix pattern on the semiconductor wafer. Each individual stress sensing structure measures stress at a specific location, and collectively they provide comprehensive stress distribution mapping across the wafer surface, resolving the contradiction between measurement precision and device complexity through spatial segmentation.
Solution Approach 2:
Different stress sensing structures are positioned at different locations on the semiconductor wafer to capture local stress variations. Each sensing structure is optimized for its specific position, enabling precise local stress measurement while maintaining overall system manageability through localized functionality.
2Measurement precision
If multiple stress sensing structures with varied characteristics are used, then the measurement precision improves, but the device complexity increases
Solution Approach 1:
The stress sensing structures utilize universal semiconductor fabrication processes and common circuit design patterns (such as Wheatstone bridge configurations) that can be replicated across multiple instances. This multi-functionality approach allows the same basic structure to measure different stress components at different orientations, reducing overall system complexity while maintaining high measurement precision.
Solution Approach 2:
The stress sensing structures vary key parameters such as orientation angles (e.g., 0°, 45°, 90°) and doping types (n-type or p-type) to detect different stress components. By changing these parameters rather than fundamentally altering the structure, the system achieves comprehensive stress measurement capability while maintaining design simplicity and manufacturability.
3Measurement precision
If stress sensing structures with different orientations are implemented, then the measurement precision of stress components improves, but the manufacturing precision requirements increase
Solution Approach 1:
Reference marks and alignment features are pre-defined in the semiconductor wafer design before fabrication. These preliminary alignment structures guide the placement and orientation of stress sensing structures during manufacturing, ensuring precise angular relationships (such as 0°, 45°, 90° orientations) without requiring complex real-time adjustment processes, thus maintaining both measurement precision and manufacturing feasibility.
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
The solution enables accurate determination of mechanical stress distribution, improving the performance and reliability of sensing elements by compensating for environmental variations and enhancing the accuracy of stress measurements.
Implementation Method 1
a plurality of stress sensing structures each comprising a different combination of sensing characteristics. The stress sensing structures are configured to detect a component of a mechanical stress on the semiconductor material, and generate an electrical signal representing the component of the mechanical stress
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Example apparatuses, and methods for determining a mechanical stress distribution in a semiconductor material are provided. An example apparatus includes a sensing cell group and voltage conversion circuitry. The sensing cell group is disposed on a surface of a semiconductor material and includes a plurality of stress sensing structures each having a different combination of sensing characteristics. Each of the stress sensing structures detect a component of a mechanical stress on the semiconductor material and generate an electrical signal representing the component of the mechanical stress. The voltage conversion circuitry receives the electrical signal representing the component of the mechanical stress from each stress sensing structure and generates a stress voltage representing the component of the mechanical stress. The stress voltages from each stress sensing structure are combined to determine a mechanical stress value representing the mechanical stress on the semiconductor material at the sensing cell group.