Process modeling and device-package simulation for optimization of MEMS gyroscopes

Typical MEMS simulation mainly focuses on device performance without considering fabrication capabilities and packaging integratibility. This practice often leads to an inefficient product development cycle and increases the cost. This paper presents an integrated simulation workflow that incorporates the modeling of fabrication process, design analysis and packaging through a case study of a MEMS tuning-fork gyroscope using Coventorware. The device design is automatically generated based on mask layout and fabrication process restrictions. Design verification is performed both at the device-level for detailed analysis and at the system-level for behavior characterization. The effect of package deformation due to the thermal stress on the MEMS device is evaluated and discussed. The multi-level simulation presented here is proved to be an efficient way to accelerate the design process and improve the device performance, and can be used effectively to optimize the gyroscope system.