Simulation of the production of functional layers for vibration sensors for tool state monitoring and finite element analysis of mechanical characteristics

A novel MEMS vibration sensor for high acceleration amplitudes was developed in silicon technology for tool state monitoring. According to the application-specific requirements, the piezoresistive detection of vibration with polysilicon piezoresistors deposited on a thin silicon membrane is best suited. The technological parameters for the production of these strain-sensitive components were determined by ICECREM, a simulation program for processing steps in semiconductor production. The vibration characteristics, 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 20 mu V/Vg corresponds well with the simulation results, 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.