Patent attributes
Apparatus, methods, and systems for bonding a cover wafer to a MEMS threshold sensors located on a silicon disc. The cover wafer is trenched to form a region when bonded to the silicon wafer that produces a gap over the contact bond pads of the MEMS threshold sensor. The method includes a series of cuts that remove part of the cover wafer over the trenches to permit additional cuts that may avoid the contact bond pads of the MEMS threshold sensor. In addition the glass frit provides for isolation of the sensor with a hermetic seal. The cavity between the MEMS threshold sensor and the cover wafer may be injected with a gas such as nitrogen to influence the properties of the MEMS threshold sensor. The MEMS threshold sensor may be utilized to sense a threshold for pressure, temperature or acceleration.
