The aim of the research project, which began in October, is to develop a technology platform for high-precision sensors based on silicon-based piezoresistive measuring resistors. These sensors record physical variables such as pressure and derived variables such as force, weight, level or flow. In various application areas, for example medicine or safety engineering for plants and processes, piezoresistive sensors with an optimally balanced bridge are particularly required.
In the bridge to be developed, the measurement signal is zero in the absence of a measurand. This makes signal processing easier, especially for very small deflections, as is common in the targeted applications.
The basis is a robust layout against technological variations, for example doping parameters, layer voltages or resistor bridge configuration. The new technology platform is said to consist of a piezoresistive sensing bridge with integrated microstructures and to use low-cost CMOS/MEMS-compatible materials. It aims to minimize on-chip cross-sensitivities, eliminating the need for costly compensations after sensor assembly.
The approaches are:
- Fine adjustment of piezo resistors using a trimmable resistor network
- Fine adjustment of piezo resistors using microheater structures
- Adjustment of resistors by local laser annealing process
The research and development work in the project “Technology Platform with Minimal Offset” (miniOffset) was funded by the German Federal Ministry of Economic Affairss and Climate Action
Funding code: 49MF220087
