Patent ID: 8637968

Claim:
A microelectronic assembly, comprising: a first microelectronic element and a second microelectronic element, each of the microelectronic elements embodying active semiconductor devices adjacent a front surface thereof, each microelectronic element having a rear surface remote from the respective front surface, and each having an electrically conductive pad exposed at the respective front surface; an interposer of a material having a coefficient of thermal expansion (“CTE”) less than 10 parts per million/° C., the interposer having oppositely facing first and second surfaces and a second conductive element extending within an opening in the interposer and being exposed at the first and second surfaces, the first surface facing the front surface of the first microelectronic element, and the second surface facing the front surface of the second microelectronic element; each of the first and second microelectronic elements further including a first conductive element extending within an opening extending from the rear surface of the respective microelectronic element towards the front surface of the respective microelectronic element, wherein the first conductive element of the first microelectronic element extends through the electrically conductive pad of the first microelectronic element, and the first conductive elements are electrically coupled with the second conductive element, wherein the first conductive element of the first microelectronic element and the second conductive element form a continuous monolithic metal region extending between the rear surface of the first microelectronic element and the second surface of the interposer, and wherein a portion of the first conductive element of the first microelectronic element has a first width in a direction parallel to the first surface, the first width being greater than a second width of an opening in the pad of the first microelectronic element.