A novel electrostatic micromachined pump for drug delivery systems

A novel structure of the micromachined pump, as the main part of the drug delivery systems, is proposed. This micropump consists of an input and an output port, three diaphragms with three active valves, microchannels and three actuation systems. Peristaltic motion is chosen for pumping mechanism; hence no special electrical specifications are required for fluids. Electrostatic actuation is used for excitation of diaphragms. This actuation type has some advantages such as low power consumption, fully MEMS integration capability and fast mechanical response. Employing active valves instead of passive counterpart solve some of the problems such as valve clogging, and valve breaking, hence increasing the performance and lifetime and decreasing the actuation voltage. Application of standard IC processes, and possibility of batch processing, the number of wafers to be bonded which are only two wafers, low actuation voltage and its small size related to the other micropumps especially piezoelectric counterpart, reduction in stiffness of diaphragm hence reduction in actuation voltage compared to the other membrane pumps are the main advantages of this design. The designed structure is simulated by finite element method using ANSYS 5.7 software.