3D STACKED PIEZORESISTIVE PRESSURE SENSOR

摘要

In a microelectromechanical system (MEMS) pressure sensor, thin and fragile bond wires that are used in the prior art to connect a MEMS pressure sensing element to an application specific integrated circuit (ASIC) for the input and output signals between these two chips are replaced by stacking the ASIC on the MEMS pressure sensing element and connecting each other using conductive vias formed in the ASIC. Gel used to protect the bond wires, ASIC and MEMS pressure sensing element can be eliminated if bond wires are no longer used. Stacking the ASIC on the MEMS pressure sensing element and connecting them using conductive vias enables a reduction in the size and cost of a housing in which the devices are placed and protected.

主权项

1. A pressure sensor device comprising:
a MEMS pressure sensing element having first and second sides with a flexible diaphragm and a Wheatstone bridge circuit on the first side; a first integrated circuit comprising a substrate with first and second sides, electronic circuitry formed into a predetermined portion of the first side and a recess formed into the second side, the second side of the first integrated circuit being attached to the first side of the MEMS pressure sensing element, the recess of the first integrated circuit and the first side of the MEMS pressure sensing element defining a substantially evacuated cavity; a first plurality of conductive vias formed into the first integrated circuit substrate such that the first plurality of vias extend through the substrate and electrically connect the Wheatstone bridge circuit of the MEMS pressure sensing element to the circuitry formed into the first side of the first integrated circuit.