Investigation and Optimization of Startup Time for MEMS Thermal Wind Sensors

For the first time, the startup time for microelectromechanical systems (MEMSs) thermal wind sensors is investigated in this article. In theoretical analysis, a complete mathematical formulation of the unsteady-state, nonperiodic transient heat transfer process was built and solved by MATLAB, indicating that the startup time was close to 13.2 s. Then, the finite element method (FEM) software COMSOL was applied to simulate the thermal field establishment based on time-dependent studies, and the result was about 13.4 s. Above all, the experiments have been performed with the startup time of 12 s, reaching an agreement with the calculation and simulation. On this basis, an optimized package scheme with a sensor chip inserted to the ceramic was proposed to reduce the startup time. The theoretical model was modified according to the structure after optimization, which was also verified by the FEM simulation. The experimental results indicated that the startup time was reduced to about 5 s with an improvement of 53.3%.