Patent ID: 8466523

Claim:
A differential pressure sensing element, comprising: an electrically insulating hollow spacer having first and second sides and having a plurality of insulated conductive through-vias extending between the first and second sides; a first silicon die attached to the first side of the electrically insulating hollow spacer, the first silicon die having corresponding first and second sides, the first silicon die comprising a first piezoresistive Wheatstone bridge circuit on a first diaphragm formed into the first silicon die, the first Wheatstone bridge being connected to electrical interconnects on the first side of the first silicon die, the first silicon die additionally comprising a plurality of insulated conductive through-silicon vias (TSVs) extending between the first and second sides of the first silicon die, interconnecting the electrical interconnects with bond pads on the second side of the first silicon die; and a second silicon die attached to the second side of the electrically insulating hollow spacer, the second silicon die having corresponding first and second sides, the second silicon die comprising a second piezoresistive Wheatstone bridge circuit on a second diaphragm formed into the second silicon die, the Wheatstone bridge being connected to electrical interconnects on the first side of the second silicon die, the second silicon die additionally comprising a plurality of insulated conductive vias to interconnect the electrical interconnects of the second silicon die with four of the TSVs of the first silicon die with the bond pads of the first silicon die whereby the electrically insulating hollow spacer, the first silicon die and the second silicon die form a cavity for dual backside absolute pressure sensing.