This paper presents a thermopneumatic micropump fabricated by micromachining. The micropump consists of a p + silicon diaphragm, a micro heater and a pair of nozzle/diffuser. The thermopneumatic actuator of this paper is characterized by a corrugated diaphragm, which is more flexible than a flat one. The diaphragm is driven by the air cavity pressure variation caused by the ohmic heating and the natural cooling. If the diaphragm of the micropump vibrates, the fluid flows in one direction through a nozzle/diffuser. The experimental result illustrates that the deflection of the corrugated diaphragm is about three times that of the flat one. The maximum flow rate of the micropump with the corrugated diaphragm is about 14 μl/min at 4 Hz when the input voltage and duty ratio are 8 V and 40%, respectively.
展开▼
