INTEGRATED REFERENCE VACUUM PRESSURE SENSOR WITH ATOMIC LAYER DEPOSITION COATED INPUT PORT

摘要

An integrated reference vacuum pressure sensor with an atomic layer deposition (ALD) coated input port comprises a housing with an port for a media to enter the housing; a substrate and stress isolation member in the housing; wherein a channel extends through the substrate and the stress isolation member, wherein a trace is embedded within the stress isolation member, wherein stress isolation member and substrate surfaces exposed to the channel are coated with an ALD; a sensor die bonded to the stress isolation member, the sensor die comprising a diaphragm having circuitry, wherein a side of the diaphragm is exposed to the channel and the circuitry is mounted to another side of the diaphragm; a via extending through the sensing die electrically connecting the circuitry to the trace; and a cover bonded to the stress isolation member, the cover having a recess, the sensor die in the recess.

主权项

1. A method for fabricating a pressure sensor, the method comprising:
forming a stress isolation member in contact with a substrate, wherein the stress isolation member and the substrate have a channel formed through the substrate and the stress isolation member; fabricating a sensor die, wherein the sensor die comprises a diaphragm having sensing circuitry formed thereon; mounting the sensor die to the stress isolation member, wherein a first side of the diaphragm is exposed to an opening of the channel; securing the stress isolation member, the substrate, and the sensor die in a housing having an input port, wherein the channel is positioned in the housing such that a pressure media entering the input port also enters the channel; coating surfaces of the stress isolation member and the substrate that are exposed to either the input port or the channel with an atomic layer deposition; electrically connecting the sensing circuitry to an external system; and sealing a second side of the sensor die within an environment having a known pressure, wherein the second side is hermetically isolated from the opening of the channel.