Silicon strain gauges offer significant economic advantages due to batch production using established semiconductor processes and technological flexibility. In particular, the versatile options for installing sensors at measurement points that are difficult or hard to access, as well as their excellent performance across a wide temperature range, open up a broad range of applications for these sensors. If the accuracy, linearity, and stability of the piezoresistive sensor elements are further improved, new application areas and operating temperature ranges can be tapped.
In the completed project, temperature sensing elements integrated directly onto the sensor chip were developed. These enable extensive and, above all, simple temperature compensation. In particular, the integrated lateral pnp transistors open up innovative solutions for temperature-compensated full bridges, each composed of two Si-DMS sensor chips.
In doing so, the additionally integrated components should have as little or a sufficiently small influence as possible on the stress-sensitive components. To achieve this, measures for the electrical isolation of the sensors on the chip were necessary. In addition, the temperature sensing elements were designed to be largely insensitive to the mechanical stress being measured (pressure, force, torsion, bending).
In connection with the project work, a solution for flush-mounted pressure sensors with temperature measurement or temperature compensation was developed, and a patent application was filed.
The research and development work described was funded by the Federal Ministry for Economic Affairs and Energy (BMWE) as part of the research project “Stress-Independent-on-Chip Temperature Sensing” (SOT).
Funding code: 49MF220093
