Simulation and fabrication of micromachined cantilever valves

Abstract This paper reports the fabrication and simulation of micromachined cantilever valves. The simulation is achieved by coupling the finite-element method (FEM) package ANSYS and the computational fluid dynamics (CFD) package FLOW3D. It is based on iterative runs for the deflection of the cantilever (ANSYS) and the fluid flow in the duct/cantilever area (FLOW3D). A macro programme controls the data flow between the simulators and the convergence of the simulation. With the coupled simulation, flow rates for cantilever valves at given pressures are calculated. These results are compared with micromachined cantilever valves fabricated by fusion bonding of a flap-containing wafer with a duct-containing water. For the release of the cantilever, toluene is used to avoid stiction while drying the chips. Agreement between measured and simulated flow rates is good and gives confidence in the use of this simulator for valve development.