Dear Colleagues,
As a relative newcomer to MEMS, I'm exploring simple switch designs using
the Cronos MUMPs process. Two adjacent Poly1 switch beams (2 microns thick
x 2 wide x 200 length) don't seem to be making electrical contact when
laterally touched together at their ends. My ohmmeter read infinite
resistance instead of the expected 2 Kohms, even though the beam ends were
clearly touching each other as indicated by several microns of deflection.
One colleague thinks that there might be a very thin oxide layer on the
beams' edges, and/or that the contact area between the two beams of about 2
x 2 microns is not enough. Another colleague suggested trying a large
number of "break/make" contact cycles to mechanically wear through the
suspected oxide layer.
I would greatly appreciate any other suggestions for achieving electrical
contact between MUMPS PolySi beams. Also, I'd like to know if anyone has
designed a robust MUMPs linear stepping mechanism (e.g. rack & pinion),
particularly if it can move a load mass of 1 milligram. (If anyone has
tried and given up on MUMPs steppers, I'd appreciate knowing that also.)
Regards,
Walt Maurer
Naval Air Warfare Center
China Lake, CA
760-939-7767
maurerwh@navair.navy.mil