Patent ID: 7594440

Claim:
A pressure sensor, comprising: first and second movable blocks formed in a handle layer; a first hinge coupled to the first and second movable blocks and configured to resist loads other than flexing of the first hinge, the first hinge being formed in the handle layer; a first gauge separated from the first hinge and aligned to provide that a moment tending to rotate one of the first or second blocks relative to the other about the first hinge applies a tensile or compressive force along a length of the first gauge, the first gauge being formed from a device layer with an oxide between the device and handle layers; wherein the sensing structure is made from an SOI wafer, and the first gauge is protected during an etching away of handle material beneath the first gauge by the oxide between the device and handle layers and an etch-resistant oxide or nitride on exterior surfaces of the first gauge; a third movable block; a second gauge; a second hinge; wherein one of the first or second movable blocks is a rim block of the pressure sensor and the other movable block is an inward-extending block that extends in an inward direction away from the rim, the first hinge being a portion of a diaphragm occupying an area between the rim block and the inward-extending block; wherein the first movable block is a rim block around the pressure sensor, the second and third movable blocks extend inward from the rim block in a direction toward each other to define a third hinge between the second and third movable blocks, the second and third hinges being portions of a diaphragm that is continuous within the rim block to provide that the first gauge disposed between the rim block and the second block sees compression at substantially a same time that the second gauge between the second block and the third block sees tension.