Hello everybody,

We are looking for the information about capacitive differential pressure
sensor with high sensitivity (10e-3 torr). Does anybody have any idea
where we can get the information in detail? The suggestion on following
topics will be appreciated.
(1) The length and width of the diaphragm is in the order of millimeter
and the thickness is in the order of micrometer. Which is the best
material for the structure, Si? PolySi? SiN?
(2) If we do not want to use bonding, how to fabricate diaphragm and
capacitor?
(2) Is it necessary to design temprature compensition structure for such
sensitivity and how to realize it? Any other noises should be considered
for the sensitivity?
(3) The capacitance change will be in the order of 10fF. Does anybody have
any idea to measure it?

Thanks.