DocumentCode :
1129929
Title :
A Micromachined Kelvin Probe With Integrated Actuator for Microfluidic and Solid-State Applications
Author :
Chu, Larry L. ; Takahata, Kenichi ; Selvaganapathy, Ponnambalam Ravi ; Gianchandani, Yogesh B. ; Shohet, J. Leon
Author_Institution :
Univ. of Wisconsin, Madison, WI, USA
Volume :
14
Issue :
4
fYear :
2005
Firstpage :
691
Lastpage :
698
Abstract :
This paper reports on a micromachined Kelvin probe structure with an integrated scanning tip and an integrated electrothermal actuator that provides axial dithering motion. The device is fabricated from metal foil by a modified microelectrodischarge machining process that allows electrical isolation within the device. In particular, it permits the incorporation of a wide epoxy plug that creates an insulating gap with low parasitic capacitance between the probe and the actuator. The epoxy structures are found to withstand the thermal and mechanical conditions encountered during device operation. The device is used to measure changes in the external surface potential of a parylene microfluidic channel as a function of varying pH of liquid inside the channel. A contact potential difference of \\approx 6~ V is measured for a change in pH from 4 to 8 within the channel. The device is also used to map embedded charge in a thin  SiO_2 layer on a Si substrate, showing it to be suitable for monitoring microelectronics manufacturing processes. \\hfill \\hbox {[1072]}
Keywords :
microactuators; microfluidics; micromachining; probes; process monitoring; surface potential; voltage measurement; Kelvin probe; axial dithering motion; electrical isolation; electrothermal actuator; integrated actuator; microelectrodischarge machining; microelectronics manufacturing processes contact potential; microfluidic application; oxide charge; solid-state application; surface potential measurement; Actuators; Electrothermal effects; Insulation; Kelvin; Machining; Microfluidics; Parasitic capacitance; Plugs; Probes; Solid state circuits; Contact potential; oxide charge; pH; surface potential;
fLanguage :
English
Journal_Title :
Microelectromechanical Systems, Journal of
Publisher :
ieee
ISSN :
1057-7157
Type :
jour
DOI :
10.1109/JMEMS.2005.845453
Filename :
1492420
Link To Document :
بازگشت