Title :
A pyroelectric-piezoelectric valve for integrated microfluidics
Author :
Duggirala, R. ; Il-Seok Son ; Lal, A.
Author_Institution :
Sch. of Electr. & Comput. Eng., Cornell Univ., Ithaca, NY, USA
Abstract :
A low-voltage, low-power microvalve that can be actuated either electrically using the inverse piezoelectric effect or thermally using the pyroelectric effect is presented here. The value consists of external laser-machined bulk piezoelectric unimorph actuators mechanically linked to surface micromachined nickel cap structures anchored on silicon nitride membrane tethers. A self-aligned mechanical linking process for the assembly of external bulk piezoelectric actuators to micromachined silicon structures enables motion from the piezoelectric unimorph to be coupled to tethers. Valve cap strokes as large as 4.8 /spl mu/m were realized for an actuation voltage of 10 V consuming switching energy of 600 nJ. Linear control of fluid flow in the 0-50 /spl mu/l/min was accomplished with pulse width modulated 10 Vpp drive at frequencies as high as 1 kHz.
Keywords :
Young´s modulus; confined flow; flow control; laser beam machining; lead compounds; microactuators; microfluidics; micromachining; microvalves; nickel; piezoelectric actuators; piezoelectric materials; piezoelectricity; pulse width modulation; pyroelectric devices; pyroelectricity; silicon compounds; 1 kHz; 10 V; 4.8 micron; 600 nJ; PZT; PbZrO3TiO3; Si; SiN-Ni; external laser-machined bulk piezoelectric unimorph actuators; fluid flow; integrated microfluidics; inverse piezoelectric effect; low-power microvalve; low-voltage microvalve; micromachined silicon structures; pulse width modulation; pyroelectric effect; pyroelectric-piezoelectric valve; self-aligned mechanical linking process; silicon nitride membrane tethers; surface micromachined nickel cap structures; switching energy; valve cap strokes; Chirp modulation; Microfluidics; Microvalves; Piezoelectric actuators; Piezoelectric effect; Pulse width modulation; Pyroelectricity; Silicon; Surface emitting lasers; Valves;
Conference_Titel :
TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7731-1
DOI :
10.1109/SENSOR.2003.1217075
