A 2kPa per stage and 1.3sccm flow rate modular two-stage electrostatic gas micropump with stiffened drive electrodes

摘要

The pressure and flow rate produced by a 3-chip (2-stage) stacked electrostatic gas micropump has been improved by incorporating structural modifications. Deep vertical trenches are used to create vertical stiffeners to reduce electrode deflection, and consequently increase pump and valve membrane displacement to generate higher compression and pressure. Electrode stiffening has improved pressure and flow rate by 4X and 15X respectively. A 3-chip stacked micropump (2-stage pump) has produced a pressure difference of 4 kPa and flow rate of 1.3 sccm at membrane actuation frequency of 24 kHz and drive amplitude of 190 Vpk·pk. Each micropump chip is 5.5 × 4 × 0.5 mm3 and pumping/microvalve membrane is 2 × 2 mm2. This is the highest pressure per stage (2 kPa) reported by a peristaltic multi-stage MEMS gas micropump with this size.