Integrated reference vacuum pressure sensor with atomic layer deposition coated input port

摘要

The device comprises a housing with an input port 102 for media to enter; a substrate 122 and a stress isolation pedestal 124. A channel 108 extends through the substrate and the stress isolation pedestal and a conductive trace 112 is embedded within the stress isolation pedestal. The stress isolation pedestal and substrate surfaces exposed to the channel are coated with an ALD layer, which protects the sensor from the possible corrosive effects of the environment. A sensor die 106 comprising a pressure sensing diaphragm 105 has one side of the diaphragm exposed to the channel and the other side comprises an integrated circuit. A via extends through the sensor die to electrically connect the integrated circuitry to the trace 112. A vacuum reference cover 120 having a recess is hermetically bonded to the stress isolation member and the sensor die is arranged in the recess.