Hi Ramji,

One way to sense temperature is to fabricate a silicon thin film resistor.
 All silicon resistors exhibit a temperature coefficient of resistance. By
using constant current excitation, one can simply read the voltage back
which varies over temperature.  Of course, the response is not necessarily
linear with temperature, so some type of lookup table can be implemented
to correct for non linearities in the temperature response.   Particularly
 if the surface the resistors are implanted on has been micromachined,  it
is important to not vary the stress across the resistor as the machined
surface moves.  Stress can produce false temperature values due to
piezoresistive effects.   Sometimes four resistors arranged in a
Wheatstone bridge pattern  or a properly designed and located single
serpentine pattern can minimize applied stress.

Another way to sense temperature is to fabricate a silicon diode.  The
excitation current induced forward voltage drop varies with temperature.
Again, some type of linearizing with temperature is needed.


Regards,

Rich Rosenblum
Principal Electrical Engineer
Ametek PMT
rich.rosenblum@ametek.com




>>>>>>>>>>>>>>>

Hi MEMS workers,

I have a question about tempeature sensing in MEMS. I
had heard something about sensing the temperature
using a serpentine structure on the substrate.
.............
Thanks a lot and regards!
ramji Dhakal

=====
Ramji Dhakal

M S Mechanical Engineering,
SUNY Binghamton, NY