Differential pressure sensor
AssigneeRosemount Aerospace Inc.
InventorsDavid P. Potasek, Jun Zheng
Life of this patent
Estimating the term…
Abstract
A differential MEMS pressure sensor includes a topping wafer with a top side and a bottom side, a diaphragm wafer having a top side connected to the bottom side of the topping wafer and a bottom side, and a backing wafer having a top side connected to the bottom side of the diaphragm wafer and a bottom side. The topping wafer includes a first cavity formed in the bottom side of the topping wafer. The diaphragm wafer includes a diaphragm, a second cavity formed in the bottom side of the diaphragm wafer underneath the diaphragm, an outer portion surrounding the diaphragm, and a trench formed in the top side of the diaphragm wafer and positioned in the outer portion surrounding the diaphragm.
Claims17
A differential MEMS pressure sensor comprising:
- a topping wafer with a top side, a bottom side, and a first cavity formed in the bottom side of the topping wafer;
- a diaphragm wafer having a top side connected to the bottom side of the topping wafer and a bottom side, wherein the diaphragm wafer comprises:
- a diaphragm;
- a second cavity formed in the bottom side of the diaphragm wafer underneath the diaphragm, wherein the second cavity has chamfered walls;
- an outer portion surrounding the diaphragm, wherein the outer portion has a chamfered portion partially defined by the chamfered walls of the second cavity and a rim portion surrounding the chamfered portion;
- and
- a trench formed in the top side of the diaphragm wafer and positioned in the outer portion surrounding the diaphragm, wherein the trench is positioned in the chamfered portion of the outer portion of the diaphragm wafer;
- and
- a backing wafer having a top side connected to the bottom side of the diaphragm wafer and a bottom side.
A system comprising:
- a differential MEMS pressure sensor comprising:
- a topping wafer with a top side, a bottom side, and a first cavity formed in the bottom side of the topping wafer;
- a diaphragm wafer having a top side connected to the bottom side of the topping wafer and a bottom side, wherein the diaphragm wafer comprises:
- a diaphragm;
- a second cavity formed in the bottom side of the diaphragm wafer underneath the diaphragm;
- and
- an outer portion surrounding the diaphragm;
- a backing wafer having a top side connected to the bottom side of the diaphragm wafer and a bottom side;
- and
- a base wafer having a top side connected to the bottom side of the backing wafer and a bottom side, wherein the base wafer comprises:
- a third cavity formed in the top side of the base wafer;
- a groove formed in the bottom side of the base wafer;
- and
- a thin wall formed between the third cavity and the groove;
- and
- a pedestal on which the differential MEMS pressure sensor is mounted;
- wherein the groove in the base wafer is configured to receive a portion of the pedestal.
Dependencies are inferred from the claim text.