M.S. Thesis Presentation by Don Creyts
Wednesday, December 12, 2001

(Dr. Peter Hesketh, advisor)

"Design and Fabrication of a Magnetic Bistable Valve"


The goal of this research is to design a MEMS magnetic bistable valve and to fabricate its actuator.  The valve is to be used in a hand-held gas chromatograph system, and must be designed to specifications that include flow-rate, power consumption, switching time and latching overpressure all while attempting to minimize the size.  Magnetic actuation is utilized because relatively large forces and large strokes may be realized and that forces can be maintain without the use of external power.  The design of the valve spans the magnetic, mechanical, and fluidic force domains.

Once plausible designs are conceived, the fabrication of the valve’s actuator is undertaken.  The processing steps used are commonplace in MEMS technologies but must be tailored for this specific application.   Processing issues concerning etching, planarization of the sacrificial material, and electrodeposition of nickel-iron will be discussed and analyzed.  The process flow for fabricating the entire valve will also be described so it is seen how the actuator fabrication can be utilized in the overall application.