Patent ID: 8791575

Claim:
A microelectronic unit, comprising: a semiconductor element having a front surface and a rear surface remote from the front surface, a plurality of active semiconductor devices therein, and a plurality of conductive pads, each conductive pad having a top surface exposed at the front surface and having a bottom surface remote from the top surface, the semiconductor element having a first opening extending from the rear surface partially through the semiconductor element towards the front surface, and at least one second opening, each second opening extending from the first opening to at least the bottom surface of a respective one of the conductive pads; at least one conductive via extending within a respective one of the at least one second opening and being electrically connected with the respective conductive pad; a dielectric region overlying an inner surface of the semiconductor element in the first opening, the dielectric region having an aperture extending through the dielectric region from the conductive via to an exposed surface of the dielectric region, wherein a contour of the aperture does not conform to a contour of the first opening, wherein the dielectric region is compliant, having a sufficiently low modulus of elasticity and sufficient thickness such that the product of the modulus and the thickness provide compliancy; at least one conductive interconnect electrically connected to a respective conductive via, the at least one conductive interconnect extending within the aperture through the dielectric region from the conductive via to the exposed surface of the dielectric region, the at least one conductive interconnect defining an outer surface having a shape that does not conform to a shape of the inner surface of the semiconductor element in the first opening; and at least one conductive contact exposed for interconnection with an external element, the conductive contact being electrically connected to a respective conductive interconnect, the at least one conductive contact being aligned in a vertical direction with a portion of the semiconductor element within the first opening, the vertical direction being a direction of a thickness of the semiconductor element between the front and rear surfaces, the at least one conductive contact being deposited in direct contact with the exposed surface of the dielectric region and wholly disposed within an area defined by edges of the first opening in a lateral direction along the rear surface, wherein the at least one conductive contact is moveable relative to the front surface of the semiconductor element when an external load is applied to the at least one conductive contact.