Microelectromechanical system pressure sensor and method for making and using
View Patent ↗According to some embodiments, an apparatus includes a substrate that defines a plane. The apparatus also includes a first conducting plate that is substantially normal to the substrate and a second conducting plate that is (i) substantially normal to the substrate and (ii) deformable in response to a pressure.
1. An apparatus, comprising:
a substrate defining a first plane;
a first finger, including a first pair of conducting plates, wherein at least one of the conducting plates is substantially normal to the substrate and deformable in response to pressure, and wherein a vacuum is provided between the first pair of conducting plates; and
a second finger, including a second pair of conducting plates, wherein at least one of the conducting plates is substantially normal to the substrate and deformable in response to pressure, and wherein a vacuum is provided between the second pair of conducting plates.
2. The apparatus of claim 1 , wherein the first pair of conducting plates is electrically isolated from the second pair of conducting plates.
3. The apparatus of claim 2 , wherein pressure is to be measured based at least in part on capacitance between the fingers.
4. The apparatus of claim 3 , wherein (i) the first finger is part of a first comb having a plurality of fingers that are electrically coupled to each other, and (ii) the second finger is part of a second comb having a plurality of fingers that are electrically coupled to each other and electrically isolated from the fingers of the first comb.
5. The apparatus of claim 4 , wherein fingers of the first are second combs are interleaved.
6. The apparatus of claim 5 , wherein the combs form an array of capacitors connected in parallel.
7. The apparatus of claim 3 , wherein the measured pressure is an absolute pressure.
8. The apparatus of claim 3 , wherein at least one of the conducting plates is deformable in response to a first pressure and at least one of the conducting plates is deformable in response to a second pressure, and wherein the measured pressure is associated with the difference between the first and second pressures.
9. The apparatus of claim 3 , wherein an increase in pressure is associated with a decrease in capacitance.
10. The apparatus of claim 3 , wherein an increase in pressure increases a distance between one of the conducting plates of the first finger and one of the conducting plates of the second finger.
11. The apparatus of claim 3 , wherein air acts as a dielectric associated with the capacitance.