Authors: J. Thomas, R. Kühnhold, R. Schnupp, G. Temmel, H. Ryssel
Affilation: Fraunhofer-Institut fur Integrierte Schaltungen, Germany
Pages: 593 - 596
Keywords: vibration sensor, polysilicon, sensitivity, resonance frequency, design optimization
A novel MEMS vibration sensor for high acceleration am-plitudes was developed in silicon technology for tool state monitoring. According to the application-specific require-ments, the piezoresistive detection of vibration with polysilicon piezoresistors deposited on a thin silicon mem-brane is best suited. The technological parameters for the production of these strain-sensitive components were deter-mined by ICECREM, a simulation program for processing steps in semiconductor production. The vibration character-istics, i.e. sensitivity, range, and resonance frequency, were predicted by analyzes with the Finite Element Method. Thus, design optimization for an optimum mechanical performance was executed. The sensor was manufactured by a CMOS compatible process. The measured sensitivity of over 20µV/Vg corresponds well with the simulation re-sults, given the deviations of the sensor shape from the simulated values caused during the production process, and represents the highest known for this working range.